JSCalendar 2.0: A JSON Representation of Calendar Data
draft-ietf-calext-jscalendarbis-17
| Document | Type | Active Internet-Draft (calext WG) | |
|---|---|---|---|
| Authors | Neil Jenkins , Robert Stepanek | ||
| Last updated | 2026-07-06 | ||
| Replaces | draft-stepanek-jscalendarbis | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Associated WG milestone |
|
||
| Document shepherd | Daniel Migault | ||
| Shepherd write-up | Show Last changed 2026-01-14 | ||
| IESG | IESG state | AD Evaluation::AD Followup | |
| Action Holder |
Andy Newton
106
|
||
| Consensus boilerplate | Yes | ||
| Telechat date | (None) | ||
| Responsible AD | Andy Newton | ||
| Send notices to | mglt.ietf@gmail.com |
draft-ietf-calext-jscalendarbis-17
Calendaring extensions N. Jenkins
Internet-Draft R. Stepanek
Obsoletes: 8984 (if approved) Fastmail
Intended status: Standards Track 6 July 2026
Expires: 7 January 2027
JSCalendar 2.0: A JSON Representation of Calendar Data
draft-ietf-calext-jscalendarbis-17
Abstract
This specification defines version "2.0" of JSCalendar, a data model
and JSON representation of calendar data that can be used for storage
and data exchange in a calendaring and scheduling environment. This
document obsoletes RFC 8984, also referred to as version "1.0" in
this document. The newly defined version "2.0" aims to improve
interoperability with existing iCalendar-based systems. It also
aligns its definitions with JSContact, such as the IANA registry
policy, validation requirements, and versioning scheme.
Note
This note is to be removed before publishing as an RFC.
Differences from RFC 8984 are documented in Appendix A.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 7 January 2027.
Copyright Notice
Copyright (c) 2026 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 6
1.1. Relation to iCalendar and jCal . . . . . . . . . . . . . 6
1.2. Relation to obsolete RFC 8984 . . . . . . . . . . . . . . 7
1.3. Notational Conventions . . . . . . . . . . . . . . . . . 8
1.4. Data Type Notations . . . . . . . . . . . . . . . . . . . 8
1.4.1. Objects and Properties . . . . . . . . . . . . . . . 8
1.4.2. Type Signatures . . . . . . . . . . . . . . . . . . . 10
1.4.3. Property Attributes . . . . . . . . . . . . . . . . . 10
1.4.4. The @type Property . . . . . . . . . . . . . . . . . 10
1.5. Common Data Types . . . . . . . . . . . . . . . . . . . . 11
1.5.1. Id . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.5.2. Int . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.5.3. UnsignedInt . . . . . . . . . . . . . . . . . . . . . 12
1.5.4. UTCDateTime . . . . . . . . . . . . . . . . . . . . . 12
1.5.5. LocalDateTime . . . . . . . . . . . . . . . . . . . . 12
1.5.6. Duration . . . . . . . . . . . . . . . . . . . . . . 13
1.5.7. SignedDuration . . . . . . . . . . . . . . . . . . . 14
1.5.8. TimeZoneId . . . . . . . . . . . . . . . . . . . . . 14
1.5.9. PatchObject . . . . . . . . . . . . . . . . . . . . . 15
1.5.10. Relation . . . . . . . . . . . . . . . . . . . . . . 16
1.5.11. Link . . . . . . . . . . . . . . . . . . . . . . . . 17
1.6. Internationalization . . . . . . . . . . . . . . . . . . 18
1.6.1. Free-Form Text . . . . . . . . . . . . . . . . . . . 18
1.6.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . 18
1.7. Validating JSCalendar . . . . . . . . . . . . . . . . . . 18
1.7.1. Case-Sensitivity . . . . . . . . . . . . . . . . . . 19
1.7.2. IANA-Registered Properties . . . . . . . . . . . . . 19
1.7.3. Reserved Properties . . . . . . . . . . . . . . . . . 19
1.7.4. Unknown Properties . . . . . . . . . . . . . . . . . 20
1.7.5. Enumerated Values . . . . . . . . . . . . . . . . . . 20
1.8. Vendor-Specific Extensions . . . . . . . . . . . . . . . 20
1.8.1. Vendor-Specific Properties . . . . . . . . . . . . . 21
1.8.2. Vendor-Specific Values . . . . . . . . . . . . . . . 22
1.9. Versioning . . . . . . . . . . . . . . . . . . . . . . . 22
1.9.1. Version Format and Requirements . . . . . . . . . . . 23
1.9.2. Current Version . . . . . . . . . . . . . . . . . . . 23
2. JSCalendar Objects . . . . . . . . . . . . . . . . . . . . . 23
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2.1. Event . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.2. Task . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.3. Group . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3. Common Properties . . . . . . . . . . . . . . . . . . . . . . 24
3.1. Metadata Properties . . . . . . . . . . . . . . . . . . . 24
3.1.1. uid . . . . . . . . . . . . . . . . . . . . . . . . . 24
3.1.2. version . . . . . . . . . . . . . . . . . . . . . . . 24
3.1.3. relatedTo . . . . . . . . . . . . . . . . . . . . . . 25
3.1.4. prodId . . . . . . . . . . . . . . . . . . . . . . . 25
3.1.5. created . . . . . . . . . . . . . . . . . . . . . . . 25
3.1.6. updated . . . . . . . . . . . . . . . . . . . . . . . 26
3.1.7. sequence . . . . . . . . . . . . . . . . . . . . . . 26
3.1.8. method . . . . . . . . . . . . . . . . . . . . . . . 26
3.2. What and Where Properties . . . . . . . . . . . . . . . . 26
3.2.1. title . . . . . . . . . . . . . . . . . . . . . . . . 26
3.2.2. description . . . . . . . . . . . . . . . . . . . . . 26
3.2.3. descriptionContentType . . . . . . . . . . . . . . . 26
3.2.4. showWithoutTime . . . . . . . . . . . . . . . . . . . 26
3.2.5. locations . . . . . . . . . . . . . . . . . . . . . . 27
3.2.6. mainLocationId . . . . . . . . . . . . . . . . . . . 27
3.2.7. virtualLocations . . . . . . . . . . . . . . . . . . 28
3.2.8. links . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2.9. locale . . . . . . . . . . . . . . . . . . . . . . . 29
3.2.10. keywords . . . . . . . . . . . . . . . . . . . . . . 29
3.2.11. categories . . . . . . . . . . . . . . . . . . . . . 29
3.2.12. color . . . . . . . . . . . . . . . . . . . . . . . . 30
3.3. Recurrence Properties . . . . . . . . . . . . . . . . . . 30
3.3.1. recurrenceId . . . . . . . . . . . . . . . . . . . . 30
3.3.2. recurrenceIdTimeZone . . . . . . . . . . . . . . . . 30
3.3.3. recurrenceRule . . . . . . . . . . . . . . . . . . . 31
3.3.4. recurrenceOverrides . . . . . . . . . . . . . . . . . 39
3.4. Sharing and Scheduling Properties . . . . . . . . . . . . 40
3.4.1. priority . . . . . . . . . . . . . . . . . . . . . . 40
3.4.2. freeBusyStatus . . . . . . . . . . . . . . . . . . . 40
3.4.3. privacy . . . . . . . . . . . . . . . . . . . . . . . 41
3.4.4. organizerCalendarAddress . . . . . . . . . . . . . . 42
3.4.5. sentBy . . . . . . . . . . . . . . . . . . . . . . . 42
3.4.6. participants . . . . . . . . . . . . . . . . . . . . 43
3.5. Alerts Properties . . . . . . . . . . . . . . . . . . . . 46
3.5.1. alerts . . . . . . . . . . . . . . . . . . . . . . . 47
3.6. Time Zone Properties . . . . . . . . . . . . . . . . . . 49
3.6.1. timeZone . . . . . . . . . . . . . . . . . . . . . . 49
4. Type-Specific JSCalendar Properties . . . . . . . . . . . . . 49
4.1. Event Properties . . . . . . . . . . . . . . . . . . . . 49
4.1.1. start . . . . . . . . . . . . . . . . . . . . . . . . 49
4.1.2. duration . . . . . . . . . . . . . . . . . . . . . . 49
4.1.3. endTimeZone . . . . . . . . . . . . . . . . . . . . . 49
4.1.4. status . . . . . . . . . . . . . . . . . . . . . . . 49
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4.2. Task Properties . . . . . . . . . . . . . . . . . . . . . 50
4.2.1. due . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.2.2. start . . . . . . . . . . . . . . . . . . . . . . . . 50
4.2.3. estimatedDuration . . . . . . . . . . . . . . . . . . 50
4.2.4. percentComplete . . . . . . . . . . . . . . . . . . . 50
4.2.5. progress . . . . . . . . . . . . . . . . . . . . . . 50
4.3. Group Properties . . . . . . . . . . . . . . . . . . . . 51
4.3.1. entries . . . . . . . . . . . . . . . . . . . . . . . 52
4.3.2. source . . . . . . . . . . . . . . . . . . . . . . . 52
5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 52
5.1. Simple Event . . . . . . . . . . . . . . . . . . . . . . 52
5.2. Simple Task . . . . . . . . . . . . . . . . . . . . . . . 53
5.3. Simple Group . . . . . . . . . . . . . . . . . . . . . . 53
5.4. All-Day Event . . . . . . . . . . . . . . . . . . . . . . 53
5.5. Task with a Due Date . . . . . . . . . . . . . . . . . . 54
5.6. Event with End Time Zone . . . . . . . . . . . . . . . . 54
5.7. Floating-Time Event (with Recurrence) . . . . . . . . . . 55
5.8. Event with Physical and Virtual Location . . . . . . . . 55
5.9. Recurring Event with Overrides . . . . . . . . . . . . . 56
5.10. Making a "This and Future" Change . . . . . . . . . . . . 57
5.11. Recurring Event with Participants . . . . . . . . . . . . 60
6. Security Considerations . . . . . . . . . . . . . . . . . . . 62
6.1. Expanding Recurrences . . . . . . . . . . . . . . . . . . 62
6.2. JSON Parsing . . . . . . . . . . . . . . . . . . . . . . 63
6.3. URI Values . . . . . . . . . . . . . . . . . . . . . . . 63
6.4. Spam . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.5. Duplication . . . . . . . . . . . . . . . . . . . . . . . 64
6.6. Time Zones . . . . . . . . . . . . . . . . . . . . . . . 64
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 64
7.1. Media Type Registration . . . . . . . . . . . . . . . . . 65
7.2. Registry Policy and Change Procedures . . . . . . . . . . 66
7.2.1. Preliminary Community Review . . . . . . . . . . . . 67
7.2.2. Submit Request to IANA . . . . . . . . . . . . . . . 68
7.2.3. Designated Expert Review . . . . . . . . . . . . . . 68
7.2.4. Change Procedures . . . . . . . . . . . . . . . . . . 68
7.3. "JSCalendar Version" Registry . . . . . . . . . . . . . . 69
7.3.1. "JSCalendar Version" Registry Template . . . . . . . 69
7.3.2. Initial Contents of the JSCalendar Version
Registry . . . . . . . . . . . . . . . . . . . . . . 69
7.4. "JSCalendar Properties" Registry . . . . . . . . . . . . 69
7.4.1. "JSCalendar Properties" Registry Template . . . . . . 69
7.4.2. Changes to the "JSCalendar Properties" Registry . . . 70
7.5. "JSCalendar Types" Registry . . . . . . . . . . . . . . . 84
7.5.1. "JSCalendar Types" Registry Template . . . . . . . . 84
7.5.2. Changes to the "JSCalendar Types" Registry . . . . . 84
7.6. "JSCalendar Enum Values" Registry . . . . . . . . . . . . 87
7.6.1. "JSCalendar Enum Values" Registry Property
Template . . . . . . . . . . . . . . . . . . . . . . 88
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7.6.2. "JSCalendar Enum Values" Registry Value Template . . 88
7.6.3. Changes to the "JSCalendar Enum Values" Registry . . 89
7.6.4. Additions to the "JSCalendar Enum Values" Registry . 89
7.6.5. Changes to the "JSCalendar Enum Values for action
(Context: Alert)" Registry . . . . . . . . . . . . . 90
7.6.6. Changes to the "JSCalendar Enum Values for display
(Context: Link)" Registry . . . . . . . . . . . . . . 90
7.6.7. Changes to the "JSCalendar Enum Values for features
(Context: VirtualLocation)" Registry . . . . . . . . 90
7.6.8. Changes to the "JSCalendar Enum Values for
freeBusyStatus (Context: Event, Task)" Registry . . . 90
7.6.9. Changes to the "JSCalendar Enum Values for kind
(Context: Participant)" Registry . . . . . . . . . . 91
7.6.10. Changes to the "JSCalendar Enum Values for
participationStatus (Context: Participant)" Registry 91
7.6.11. Changes to the "JSCalendar Enum Values for privacy
(Context: Event, Task)" Registry . . . . . . . . . . 91
7.6.12. Changes to the "JSCalendar Enum Values for progress
(Context: Task, Participant)" Registry . . . . . . . 91
7.6.13. Changes to the "JSCalendar Enum Values for relation
(Context: Relation)" Registry . . . . . . . . . . . . 92
7.6.14. Changes to the "JSCalendar Enum Values for relativeTo
(Context: OffsetTrigger, Location)" Registry . . . . 92
7.6.15. Changes to the "JSCalendar Enum Values for roles
(Context: Participant)" Registry . . . . . . . . . . 92
7.6.16. Changes to the "JSCalendar Enum Values for
scheduleAgent (Context: Participant)" Registry . . . 93
7.6.17. Changes to the "JSCalendar Enum Values for status
(Context: Event)" Registry . . . . . . . . . . . . . 93
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 93
8.1. Normative References . . . . . . . . . . . . . . . . . . 93
8.2. Informative References . . . . . . . . . . . . . . . . . 96
Appendix A. Differences from RFC 8984 . . . . . . . . . . . . . 98
A.1. Applied Errata . . . . . . . . . . . . . . . . . . . . . 98
A.2. Changed Property Definitions . . . . . . . . . . . . . . 98
A.2.1. Obsoleted Properties . . . . . . . . . . . . . . . . 98
A.2.2. Reserved Properties . . . . . . . . . . . . . . . . . 101
A.2.3. Updated Properties . . . . . . . . . . . . . . . . . 104
A.2.4. New Properties . . . . . . . . . . . . . . . . . . . 107
A.3. Changed Type Definitions . . . . . . . . . . . . . . . . 109
A.3.1. Obsoleted Types . . . . . . . . . . . . . . . . . . . 109
A.3.2. Updated Types . . . . . . . . . . . . . . . . . . . . 109
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 109
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 109
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1. Introduction
This document defines a data model for calendar event and task
objects, or groups of such objects, in electronic calendar
applications and systems. The format aims to be unambiguous,
extendable, and simple to process.
The key design considerations for this data model are as follows:
* The attributes of the calendar entry represented must be described
as simple key-value pairs. Simple events are simple to represent;
complex events can be modeled accurately.
* Wherever possible, there should be only one way to express the
desired semantics, reducing complexity.
* The data model should avoid ambiguities, which often lead to
interoperability issues between implementations.
* The data model should be generally compatible with the iCalendar
data format [RFC5545] [RFC7986] and extensions, but the
specification should add new attributes where the iCalendar format
currently lacks expressivity, and drop seldom-used, obsolete, or
redundant properties. This means translation with no loss of
semantics should be easy with most common iCalendar files.
* Extensions, such as new properties and components, should not
require updates to this document.
The representation of this data model is defined in the Internet JSON
(I-JSON) format [RFC7493], which is a strict subset of the JSON data
interchange format [RFC8259]. Using JSON is mostly a pragmatic
choice: its widespread use makes JSCalendar easier to adopt and the
ready availability of production-ready JSON implementations
eliminates a whole category of parser-related interoperability
issues, which iCalendar has often suffered from.
1.1. Relation to iCalendar and jCal
The iCalendar data format [RFC5545], a widely deployed interchange
format for calendaring and scheduling data, has served calendaring
vendors for a long time but contains some ambiguities and pitfalls
that cannot be overcome without backward-incompatible changes.
Sources of implementation errors include the following:
* iCalendar defines various formats for local times, UTC, and dates.
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* iCalendar requires custom time zone definitions within a single
calendar component.
* iCalendar's definition of recurrence rules is ambiguous and has
resulted in differing interpretations, even between experienced
calendar developers.
* The iCalendar format itself causes interoperability issues due to
misuse of CRLF-terminated strings, line continuations, and subtle
differences among iCalendar parsers.
In recent years, many new products and services have appeared that
wish to use a JSON representation of calendar data within their APIs.
The JSON format for iCalendar data, jCal [RFC7265], is a direct
mapping between iCalendar and JSON. In its effort to represent full
iCalendar semantics, it inherits all the same pitfalls and uses a
complicated JSON structure.
As a consequence, since the standardization of jCal, the majority of
implementations and service providers either kept using iCalendar or
came up with their own proprietary JSON representations, which are
incompatible with each other and often suffer from common pitfalls,
such as storing event start times in UTC (which become incorrect if
the time zone's rules change in the future). JSCalendar meets the
demand for JSON-formatted calendar data that is free of such known
problems and provides a standard representation as an alternative to
the proprietary formats.
Two additional documents define the relation of JSCalendar and
iCalendar: [I-D.ietf-calext-icalendar-jscalendar-extensions] defines
new iCalendar properties and parameters.
[I-D.ietf-calext-jscalendar-icalendar] defines how to convert
JSCalendar data from and to iCalendar.
1.2. Relation to obsolete RFC 8984
This document obsoletes the data model originally defined in
[RFC8984]. The goal of this new document is to improve
interoperability with systems that also make use of iCalendar
[RFC5545]. It obsoletes elements which semantically conflict with
related iCalendar elements. It reserves elements which require
further work by IETF. Further differences from [RFC8984] are
documented in Appendix A.
This document also aligns general definitions of JSCalendar with
JSContact [RFC9553]: It defines the same notation for specifying data
types (Section 1.4), redefines the PatchObject type to allow patching
existing array entries (Section 1.5.9) and provides the same guidance
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on how to process URIs and internationalized text (Section 1.5.9).
Also, it defines the same validation scheme (Section 1.5.9), the same
versioning scheme (Section 1.9), and the same IANA registry policy
and change procedures (Section 7.2).
1.3. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The underlying format used for this specification is JSON.
Consequently, the terms "object" and "array" as well as the four
primitive types (strings, numbers, booleans, and null) are to be
interpreted as described in Section 1 of [RFC8259].
Some examples in this document contain "partial" JSON documents used
for illustrative purposes. In these examples, an ellipsis "..." is
used to indicate a portion of the document that has been removed for
compactness.
1.4. Data Type Notations
This section introduces the notations and terminology used to define
data types in JSCalendar.
The underlying format for JSCalendar is JSON, so its data types also
build on JSON values. The terms "object" and "array" as well as the
four primitive types ("strings", "numbers", "booleans", and "null")
are to be interpreted as described in Section 1 of [RFC8259]. All
JSCalendar data MUST be valid according to the constraints given in
I-JSON [RFC7493]. Unless otherwise noted, all member names in JSON
objects and all string values are case-sensitive. Within the context
of JSON objects, the term "key" is synonymous with "member name" as
defined in Section 1 of [RFC8259].
1.4.1. Objects and Properties
JSCalendar defines data types for calendar information such as
calendar events and todo list items. This information typically
consists of multiple related elements; for example, a datetime and a
duration value together define the timespan of a calendar event.
These related elements are organized in JSCalendar objects. A
JSCalendar object is a JSON object that has the following:
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1. A unique type name registered in the IANA "JSCalendar Types"
registry (Section 7.5).
2. One or more object members for which the name and allowed value
types are specified. Such members are called "properties".
3. One property named "@type" with a string value that matches the
type name of the JSCalendar object. In general, this property
does not need to be set explicitly as outlined in Section 1.4.4.
The following sections specify how to define JSCalendar object types.
Sections 1.7 and 1.8 then define the exact requirements for property
names.
The next paragraph illustrates how a JSCalendar object is defined.
The names "Foo" and "baz" are only for demonstration and have no
meaning outside the example.
A Foo object has the following properties:
@type: String. The JSCalendar type of the object. The value MUST
be "Foo", if set.
baz: Number (mandatory). The baz level of the contact. The value
MUST be an integer greater than 0 and less than 10.
The above paragraph illustrates the following:
* It defines a JSCalendar object type named "Foo" having two
properties, named "@type" and "baz".
* The "@type" property adheres to the rules outlined in
Section 1.4.4. Because of this, it is neither defined to be
mandatory nor optional, as this depends on how the Foo object type
is used.
* The baz property value MUST be valid according to the definition
of the Number type.
* The property has one attribute, "mandatory", which specifies that
the property MUST be present for a value of the Foo object type to
be valid.
* The free-text description of the baz property describes the
semantics and further restrictions for its values.
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1.4.2. Type Signatures
Type signatures are given for all JSON values and JSCalendar
definitions in this document. The following conventions are used:
String: The JSON string type.
Number: The JSON number type.
Boolean: The JSON boolean type.
A[B]: A JSON object where all keys are of type A and all values are
of type B.
A[]: A JSON array of values of type A.
A|B: The value is either of type A or of type B.
*: The type is undefined (the value could be any type, although
permitted values may be constrained by the context of this value).
Section 1.5 defines common data types, including signed or unsigned
integers and dates.
1.4.3. Property Attributes
Object properties may also have a set of attributes defined along
with the type signature. These have the following meanings:
mandatory: The property MUST be set for an instance of this object
to be valid.
optional: The property can, but need not, be set for an instance of
this object to be valid.
default: This is followed by a JSON value. That value will be used
for this property if it is omitted.
defaultType: This is followed by the name of a JSCalendar object
type. A property value of JSCalendar object type is expected to
be of this named type, in case it omits the "@type" property.
1.4.4. The @type Property
@type: String. The JSCalendar type of a JSON object. It MUST match
the type name of the JSCalendar object of which the JSON object is
an instance of.
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The purpose of the "@type" property is to help implementations
identify which JSCalendar object type a given JSON object represents.
Implementations MUST validate that JSON objects with this property
conform to the specification of the JSCalendar object type of that
name.
In many cases, the "@type" property value is implied by where its
object occurs in JSCalendar data. Assuming that both A and B are
JSCalendar object types:
* An object that is set as the value for a property with type
signature "A" MAY have the "@type" property set. If the "@type"
property is not set, then its value is implied to be A by the
property definition.
* An object that is set as the value for a property with type
signature "A|B (defaultType: A)" MAY have the "@type" property set
if it is an instance of A. It MUST have the "@type" property set
if it is an instance of B. If, instead, the defaultType attribute
is not defined, then the "@type" property MUST also be set for A.
* An object that is not the value of a property, such as the topmost
object in JSON data (directly or as a member of an array), MUST
have the "@type" property set.
1.5. Common Data Types
In addition to the standard JSON data types, the following data types
are used in this specification:
1.5.1. Id
Where "Id" is given as a data type, it means a String of at least 1
and a maximum of 255 octets in size, and it MUST only contain
characters from the "URL and Filename Safe" base64url alphabet, as
defined in Section 5 of [RFC4648], excluding the pad character ("=").
This means the allowed characters are the ASCII alphanumeric
characters ("A-Za-z0-9"), hyphen ("-"), and underscore ("_").
In many places in JSCalendar, a JSON map is used where the map keys
are of type Id and the map values are all the same type of object.
This construction represents an unordered set of objects, with the
added advantage that each entry has a name (the corresponding map
key). This allows for more concise patching of objects, and, when
applicable, for the objects in question to be referenced from other
objects within the JSCalendar object.
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Unless otherwise specified for a particular property, there are no
uniqueness constraints on an Id value (other than, of course, the
requirement that you cannot have two values with the same key within
a single JSON map). For example, two Event objects might use the
same Ids in their respective "links" properties or, within the same
Event object, the same Id could appear in the "participants" and
"alerts" properties. These situations do not imply any semantic
connections among the objects.
1.5.2. Int
Where "Int" is given as a data type, it means an integer in the range
-2^53+1 <= value <= 2^53-1, the safe range for integers stored in a
floating-point double, represented as a JSON Number.
1.5.3. UnsignedInt
Where "UnsignedInt" is given as a data type, it means an integer in
the range 0 <= value <= 2^53-1, represented as a JSON Number.
1.5.4. UTCDateTime
This is a String in the "date-time" format [RFC3339], with the
further restrictions that any letters MUST be in uppercase, and the
time offset MUST be the character "Z". Fractional second values MUST
NOT be included.
For example, "2010-10-10T10:10:10Z" is conformant, but
"2010-10-10T10:10:10.0Z" or "2010-10-10T10:10:10.123Z" are invalid.
1.5.5. LocalDateTime
This is a date-time String with no time zone/offset information. It
is otherwise in the same format as UTCDateTime. For example,
"2006-01-02T15:04:05" is valid. The time zone to associate with the
LocalDateTime comes from the "timeZone" property of the JSCalendar
object (see Section 3.6.1). If no time zone is specified, the
LocalDateTime is _floating_. Floating date-times are not tied to any
specific time zone. Instead, they occur in each time zone at the
given wall-clock time (as opposed to the same instant point in time).
A time zone may have a period of discontinuity, for example, a change
from standard time to daylight savings time. When converting local
date-times that fall in the discontinuity to UTC, the offset before
the transition MUST be used.
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For example, in the "America/Los_Angeles" time zone, the date-time
"2020-11-01T01:30:00" occurs twice: before the daylight savings time
(DST) transition with a UTC offset of -07:00 and again after the
transition with an offset of -08:00. When converting to UTC, we
therefore use the offset before the transition (-07:00), so it
becomes "2020-11-01T08:30:00Z".
Similarly, in the "Australia/Melbourne" time zone, the date-time
"2020-10-04T02:30:00" does not exist; the clocks are moved forward
one hour for DST on that day at 02:00. However, such a value may
appear during calculations (see duration semantics in Section 1.5.6)
or due to a change in time zone rules (so it was valid when the event
was first created). Again, it is interpreted as though the offset
before the transition is in effect (+10:00); therefore, when
converted to UTC, we get "2020-10-03T16:30:00Z".
1.5.6. Duration
Where Duration is given as a type, it means a length of time
represented by a subset of the ISO 8601 duration format, as specified
by the following ABNF [RFC5234]:
dur-second = 1*DIGIT "S"
dur-minute = 1*DIGIT "M" [dur-second]
dur-hour = 1*DIGIT "H" [dur-minute]
dur-time = "T" (dur-hour / dur-minute / dur-second)
dur-day = 1*DIGIT "D"
dur-week = 1*DIGIT "W"
dur-cal = (dur-week [dur-day] / dur-day)
duration = "P" (dur-cal [dur-time] / dur-time)
A duration specifies an abstract number of weeks, days, hours,
minutes, and/or seconds. A duration specified using weeks or days
does not always correspond to an exact multiple of 24 hours. The
number of hours/minutes/seconds may vary if it overlaps a period of
discontinuity in the event's time zone, for example, a change from
standard time to daylight savings time. Leap seconds MUST NOT be
considered when adding or subtracting a duration to/from a
LocalDateTime.
To add a duration to a LocalDateTime:
1. Add any week or day components of the duration to the date. A
week is always the same as seven days.
2. If a time zone applies to the LocalDateTime, convert it to a
UTCDateTime following the semantics in Section 1.5.5.
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3. Add any hour, minute, or second components of the duration (in
absolute time).
4. Convert the resulting UTCDateTime back to a LocalDateTime in the
time zone that applies.
To subtract a duration from a LocalDateTime, the steps apply in
reverse:
1. If a time zone applies to the LocalDateTime, convert it to UTC
following the semantics in Section 1.5.5.
2. Subtract any hour, minute, or second components of the duration
(in absolute time).
3. Convert the resulting UTCDateTime back to LocalDateTime in the
time zone that applies.
4. Subtract any week or day components of the duration from the
date.
5. If the resulting time does not exist on the date due to a
discontinuity in the time zone, use the semantics in
Section 1.5.5 to convert to UTC and back to get a valid
LocalDateTime.
These semantics match the iCalendar DURATION value type ([RFC5545],
Section 3.3.6).
1.5.7. SignedDuration
A SignedDuration represents a length of time that may be positive or
negative and is typically used to express the offset of a point in
time relative to an associated time. It is represented as a
Duration, optionally preceded by a sign character. It is specified
by the following ABNF:
signed-duration = ["+" / "-"] duration
A negative sign indicates a point in time at or before the associated
time; a positive or no sign indicates a time at or after the
associated time.
1.5.8. TimeZoneId
Where "TimeZoneId" is given as a data type, it means a String that is
a time zone name in the IANA Time Zone Database [TZDB]. The zone
rules of the respective IANA time zone records apply.
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1.5.9. PatchObject
A PatchObject is of type "String[*]" and represents an unordered set
of patches on a JSON object. Each key is a path represented in a
subset of the JSON Pointer format [RFC6901]. The paths have an
implicit leading "/", so each key is prefixed with "/" before
applying the JSON Pointer evaluation algorithm.
A patch within a PatchObject is only valid if all the following
conditions apply:
1. The pointer MAY reference inside an array, but if the last
reference token in the pointer is an array index, then the patch
value MUST NOT be null. The pointer MUST NOT use "-" as an array
index in any of its reference tokens (i.e., you MUST NOT insert/
delete from an array, but you MAY replace the contents of its
existing members. To add or remove members, one needs to replace
the complete array value).
2. All reference tokens prior to the last (i.e., the value after the
final slash) MUST already exist as values in the object being
patched. If the last reference token is an array index, then a
member at this index MUST already exist in the referenced array.
3. There MUST NOT be two patches in the PatchObject where the
pointer of one is the prefix of the pointer of the other, e.g.,
"alerts/1/offset" and "alerts".
4. The value for the patch MUST be valid for the property being set
(of the correct type and obeying any other applicable
restrictions), or if null, the property MUST be optional.
The value associated with each pointer determines how to apply that
patch:
* If null, remove the property from the patched object. If the key
is not present, this is a no-op.
* If non-null, set the value given as the value for this property
(this may be a replacement or addition to the object being
patched).
A PatchObject does not define its own "@type" (Section 1.4.4)
property. Instead, the "@type" property in a patch MUST be handled
as any other patched property value.
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Implementations MUST reject a PatchObject in its entirety if any of
its patches are invalid. Implementations MUST NOT apply partial
patches.
The PatchObject format is used to significantly reduce file size and
duplicated content when specifying variations to a common object,
such as with recurring events or when translating the data into
multiple languages. It can also better preserve semantic intent if
only the properties that should differ between the two objects are
patched. For example, if one person is not going to a particular
instance of a regularly scheduled event, in iCalendar, you would have
to duplicate the entire event in the override. In JSCalendar, this
is a small patch to show the difference. As only this property is
patched, if the location of the event is changed, the occurrence will
automatically still inherit this.
1.5.10. Relation
A Relation object defines the relation to other objects, using a
possibly empty set of relation types. The object that defines this
relation is the linking object, while the other object is the linked
object. A Relation object has the following properties:
@type: String.
This specifies the type of this object. This MUST be "Relation",
if set.
relation: String[Boolean] (optional; default: empty Object).
This describes how the linked object is related to the linking
object. The relation is defined as a set of relation types. Keys
in the set MUST be one of the following values, specified in the
property definition where the Relation object is used, a value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
first: The linked object is the first in a series the linking
object is part of.
next: The linked object is next in a series the linking object is
part of.
child: The linked object is a subpart of the linking object.
parent: The linking object is a subpart of the linked object.
The value for each key in the map MUST be true. The empty Object
value represents a "parent" relation, unless defined differently
for a specific property.
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1.5.11. Link
A Link object represents an external resource associated with the
linking object. It has the following properties:
@type: String.
This specifies the type of this object. This MUST be "Link", if
set.
href: String (mandatory).
This is a URI[RFC3986] from which the resource may be fetched.
This MAY be a "data:" URL [RFC2397], but it is recommended that
the file be hosted on a server to avoid embedding arbitrarily
large data in JSCalendar object instances.
contentType: String (optional).
This is the media type [RFC6838] of the resource, if known.
size: UnsignedInt (optional).
This is the size, in octets, of the resource when fully decoded
(i.e., the number of octets in the file the user would download),
if known. Note that this is an informational estimate, and
implementations must be prepared to handle the actual size being
quite different when the resource is fetched.
rel: String (optional).
This identifies the relation of the linked resource to the object.
If set, the value MUST be a link relation type as defined in
Section 2.1 of [RFC8288] .
display: String[Boolean] (optional).
This is a set of intended purposes of a link to an image. The
keys MUST be one of the following values, another value registered
in the IANA "JSCalendar Enum Values" registry, or a vendor-
specific value (see Section 1.8):
badge: an image meant to be displayed alongside the title of the
object
graphic: a full image replacement for the object itself
fullsize: an image that is used to enhance the object
thumbnail: a smaller variant of "fullsize" to be used when space
for the image is constrained
The value for each key in the map MUST be true.
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title: String (optional).
This is a human-readable, plain-text description of the resource.
1.6. Internationalization
JSCalendar aims to be used for international calendaring data.
Notably, text values such as event titles or locations are likely to
cover a wide range of languages and cultures. This section describes
internationalization for free-form text values as well as Uniform
Resource Identifiers (URIs).
1.6.1. Free-Form Text
Properties having free-form text values MAY contain any valid
sequence of Unicode characters encoded as a JSON string. Such values
can contain unidirectional left-to-right and right-to-left text, as
well as bidirectional text using Unicode Directional Formatting
Characters as described in Section 2 of [UBiDi]. Implementations
setting bidirectional text MUST make sure that each property value
complies with the requirements of the Unicode Bidirectional
Algorithm. Implementations MUST NOT assume that text values of
adjacent properties are processed or displayed as a combined string;
for example, the values of an event title and description may or may
not be rendered together.
1.6.2. URIs
Several properties require their string value to be a URI as defined
in [RFC3986]. Implementations MUST make sure to use proper percent-
encoding for URIs that cannot be represented using unreserved URI
characters. Section 3.1 of [RFC3987] defines how to convert
Internationalized Resource Identifiers to URIs. JSCalendar makes no
recommendation on how to display URIs, but the WHATWG URL Living
Standard (see "Internationalization and special characters"
(Section 4.8.3) of [WHATWG-URL]) provides guidance for URLs found in
the context of a web browser.
1.7. Validating JSCalendar
This specification distinguishes between three kinds of properties
regarding validation: IANA-registered properties and unknown
properties, which are defined in this section, and vendor-specific
properties, which are defined in Section 1.8.1. A JSCalendar object
is invalid if any of its properties are invalid.
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This document defines whether each property is mandatory or optional.
A mandatory property MUST be present for a JSCalendar object to be
valid. An optional property does not need to be present. The values
of both required and optional properties MUST adhere to the data type
and definition of that property.
1.7.1. Case-Sensitivity
All property names, object type names, and enumerated values are
case-sensitive, unless explicitly stated otherwise in their
definitions. Implementations MUST handle a JSCalendar object as
invalid if a type name, property name, or enumerated value only
differs in case from one defined for any JSCalendar version known to
that implementation. This applies regardless of what JSCalendar
version the object defines in its "version" (Section 3.1.2) property.
Section 1.7.4 defines how to handle unknown properties.
1.7.2. IANA-Registered Properties
An IANA-registered property is any property that has been registered
according to the IANA property registry rules as outlined in
Section 7. All properties defined in this specification, including
their object value types and enumerated values, are registered at
IANA.
Implementations MUST validate IANA-registered properties in
JSCalendar data, unless they are unknown to the implementation
(Section 1.7.4). They MUST reject invalid IANA-registered
properties. A property is invalid if its name matches the name of an
IANA-registered property but the value violates its definition
according to the JSCalendar specification version defined in the
"version" (Section 3.1.2) property.
IANA-registered property names MUST NOT contain ASCII control
characters (U+0000 to U+001F, U+007F), the COLON (U+003A), or the
QUOTATION MARK (U+0022). They MUST only contain ASCII alphanumeric
characters that match the ALPHA and DIGIT rules defined in
Appendix B.1 of [RFC5234] or the COMMERCIAL AT (U+0040) character.
IANA-registered property names MUST be notated in lower camel case.
1.7.3. Reserved Properties
IANA-registered properties can be reserved (Section 7.2).
Implementations MUST NOT set properties having a reserved name in
JSCalendar objects for which this property is reserved, or all
objects if the property context in the registry is "not applicable".
Reserved properties have no type and their type signature is "not
applicable". Any JSCalendar object including a property which is
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reserved in context of this object MUST be considered invalid.
This document reserves one property:
1.7.3.1. extra
extra: not applicable. The reserved property "extra" provides
implementors with a property name that is certain to never occur
as a property in any JSCalendar object. Implementations might
want to map unknown or vendor-specific properties to a variable
with this name, but this is implementation-specific.
1.7.4. Unknown Properties
Implementations may encounter JSCalendar data where a property name
is unknown to that implementation but the name adheres to the
syntactic restrictions of IANA-registered property names.
Implementations MUST make sure that such a name does not violate the
case-sensitivity rules defined in Section 1.7.1. If the property
name is valid, then implementations MUST NOT treat such properties as
invalid. Instead, they MUST preserve them in the JSCalendar object.
Implementations that create or update JSCalendar data MUST only set
IANA-registered properties or vendor-specific properties. Preserving
properties that are unknown to the implementation is to allow
applications and services to interoperate without data loss, even if
not all of them implement the same set of JSCalendar extensions.
1.7.5. Enumerated Values
Several properties in this document restrict their allowed values to
a list of String values. These values are case-sensitive. If not
noted otherwise for a specific property, the initial list of values
for such properties is registered at IANA in the "JSCalendar Enum
Values" registry (Section 7.6). Implementations MUST only set IANA-
registered or vendor-specific (Section 1.8.2) values for such
properties.
1.8. Vendor-Specific Extensions
Vendors may extend properties and values for experimentation or to
store contacts data that is only useful for a single service or
application. Such extensions are not meant for interoperation. If,
instead, interoperation is desired, vendors are strongly encouraged
to define and register new properties, types, and values at IANA as
defined in Section 7. Section 1.7.2 defines the naming conventions
for IANA-registered elements.
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1.8.1. Vendor-Specific Properties
Vendor-specific property names MUST start with a vendor-specific
prefix followed by a name, as produced by the "v-extension" ABNF
below. The prefix and name together form the property name. The
vendor-specific prefix MUST be a domain name under control of the
service or application that sets the property, but it need not
resolve in the Domain Name System [RFC1034] [RFC1035]. The prefix
"ietf.org" and its subdomain names are reserved for IETF
specifications. The name MUST NOT contain the TILDE (U+007E) and
SOLIDUS (U+002F) characters, as these require special escaping when
encoding a JSON Pointer [RFC6901] for that property.
Vendor-specific properties MAY be set in any JSCalendar object.
Implementations MUST preserve vendor-specific properties in
JSCalendar data, irrespective if they know their use. They MUST NOT
reject the property value as invalid, unless they are in control of
the vendor-specific property as outlined in the above paragraph.
The ABNF rule "v-extension" formally defines valid vendor-specific
property names. Note that the vendor prefix allows for more values
than Internationalized Domain Names (IDNs)[RFC8499]; therefore,
JSCalendar implementations can simply validate property names without
implementing the full set of rules that apply to domain names.
v-extension = v-prefix ":" v-name
v-prefix = v-label *("." v-label)
v-label = alnum-int / alnum-int *(alnum-int / "-") alnum-int
alnum-int = ALPHA / DIGIT / NON-ASCII
; see RFC 6350, Section 3.3
v-name = 1*(WSP / "!" / %x23-2e / %x30-7d / NON-ASCII)
; any characters except CTLs, DQUOTE, SOLIDUS, and TILDE
Figure 1: ABNF Rules for Vendor-Specific Property Names
The value of vendor-specific properties can be any valid JSON value,
and naming restrictions do not apply to such values. Specifically,
if the property value is a JSON object, then the keys of such objects
need not be named as vendor-specific properties, as illustrated in
Figure 2:
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"example.com:foo": "bar",
"example.com:foo2": {
"bar": "baz"
}
Figure 2: Examples of Vendor-Specific Properties
1.8.2. Vendor-Specific Values
Some JSCalendar IANA-registered properties allow their values to be
vendor-specific. One such example is a Participant object's "kind"
(Section 3.4.6) property, which enumerates its standard values but
also allows for arbitrary vendor-specific values. Such vendor-
specific values MUST be valid "v-extension" values as defined in
Section 1.8.1. The example in Figure 3 illustrates this:
"kind": "example.com:baz"
Figure 3: Example of a Vendor-Specific Value
Vendors are strongly encouraged to specify a new standard value once
a vendor-specific one turns out to also be useful for other systems.
1.9. Versioning
A JSCalendar Group (Section 2.3), Event (Section 2.1) and Task
(Section 2.2) indicate which JSCalendar version its IANA-registered
properties and values are based on. The version is indicated both in
the version (Section 3.1.2) property of a JSCalendar object and in
the version (Section 7.1) parameter of the JSCalendar media type.
All IANA-registered elements indicate the version at which they were
introduced or obsoleted.
A JSCalendar version consists of a major and minor version.
Differing major version values indicate substantial differences in
JSCalendar semantics and format. Implementations MUST be prepared
for property definitions and other JSCalendar elements that differ in
a backwards-incompatible manner.
Differing minor version values indicate additions that enrich
JSCalendar data but do not introduce backwards-incompatible changes.
Typically, these are new property enum values or properties with a
narrow semantic scope. A new minor version MUST NOT require
implementations to change their processing of JSCalendar data.
Changing the major version number resets the minor version number to
zero.
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1.9.1. Version Format and Requirements
A version value starts with the numeric major version, followed by
the FULL STOP character (U+002E), followed by the numeric minor
version. Later versions are numerically higher than former versions,
with the major version being more significant than the minor version.
A version value is produced by the following ABNF:
jsversion = 1*DIGIT "." 1*DIGIT
Figure 4: The ABNF for JSCalendar Version Values
1.9.2. Current Version
This specification registers JSCalendar version values "1.0" and
"2.0" in the JSCalendar Version registry. Version "2.0" applies for
JSCalendar data that conforms with the specifications in this
document. Version "1.0" applies for JSCalendar data that conforms
with the now obsolete specifications of [RFC8984].
2. JSCalendar Objects
This section describes the calendar object types specified by
JSCalendar.
2.1. Event
Media type: "application/jscalendar+json;type=event"
An Event represents a scheduled amount of time on a calendar,
typically a meeting, appointment, reminder, or anniversary. It is
required to start at a certain point in time and typically has a non-
zero duration. Multiple participants may partake in the event.
The "@type" (Section 1.4.4) property is mandatory, it MUST be set to
value "Event".
2.2. Task
Media type: "application/jscalendar+json;type=task"
A Task represents an action item, assignment, to-do item, or work
item. It may start and be due at certain points in time, take some
estimated time to complete, and recur, none of which is required.
The "@type" (Section 1.4.4) property is mandatory, it MUST be set to
value "Task".
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2.3. Group
Media type: "application/jscalendar+json;type=group"
A Group is a collection of Event (Section 2.1) and/or Task
(Section 2.2) objects. Typically, objects are grouped by topic
(e.g., by keywords) or calendar membership.
The "@type" (Section 1.4.4) property is mandatory, it MUST be set to
value "Group".
3. Common Properties
This section describes the properties that are common to the various
JSCalendar object types. Specific JSCalendar object types may only
support a subset of these properties. The object type definitions in
Section 4 describe the set of supported properties per type.
3.1. Metadata Properties
3.1.1. uid
uid: String (mandatory). This is a globally unique identifier used
to associate objects representing the same event, task, group, or
other object across different systems, calendars, and views. For
recurring events and tasks, the UID is associated with the base
object and therefore is the same for all occurrences; the
combination of the UID with a "recurrenceId" identifies a
particular instance.
The generator of the identifier MUST guarantee that the identifier
is unique. [RFC9562] describes a range of established algorithms
to generate universally unique identifiers (UUIDs). UUID version
4, described in Section 4.4 of [RFC9562], is RECOMMENDED.
For compatibility with UIDs [RFC5545], implementations MUST be
able to receive and persist values of at least 255 octets for this
property, but they MUST NOT truncate values in the middle of a
UTF-8 multi-octet sequence.
3.1.2. version
version: String. The JSCalendar version of this object. The value
MUST be one of the IANA-registered JSCalendar Version values for
the "version" property.
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For version "2.0" or higher, a Group object MUST set the "version"
property, but the Event or Task objects that are values in its
"entries" property MUST NOT set the "version" property. In
contrast, an Event or Task object that is represented without an
enclosing Group object MUST set the "version" property, unless
specified otherwise. This is to prevent conflicting version
values to occur in JSCalendar data.
For version "1.0", the "version" property is optional.
3.1.3. relatedTo
relatedTo: String[Relation] (optional). This relates the object to
other JSCalendar objects. Each key in the map is the "uid"
property value of a related object. The value defines the type of
the relation.
If an object is split to make a "this and future" change to a
recurrence, the original object MUST be truncated to end at the
previous occurrence before this split, and a new object is created
to represent all the occurrences after the split. A "next"
relation MUST be set on the original object's "relatedTo"
property, keyed by the "uid" of the new object. A "first"
relation MUST be set on the new object, keyed by the "uid" of the
first object in the series. Clients can then follow these "uid"
keys to get the complete set of objects if the user wishes to
modify them all at once.
3.1.4. prodId
prodId: String (optional). This is the identifier for the product
that last updated the JSCalendar object. This should be set
whenever the data in the object is modified (i.e., whenever the
"updated" property is set).
The vendor of the implementation MUST ensure that this is a
globally unique identifier, using some technique such as a Formal
Public Identifier (FPI) value, as defined in [ISO.9070.1991].
This property SHOULD NOT be used to alter the interpretation of a
JSCalendar object beyond the semantics specified in this document.
For example, it is not to be used to further the understanding of
nonstandard properties, a practice that is known to cause long-
term interoperability problems.
3.1.5. created
created: UTCDateTime (optional). This is the date and time this
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object was initially created.
3.1.6. updated
updated: UTCDateTime (mandatory). This is the date and time the data
in this object was last modified (or its creation date/time if not
modified since).
3.1.7. sequence
sequence: UnsignedInt (optional; default: 0). This property
indicates the revision of the calendar object. For scheduled
calendar objects, its value must be incremented according to the
rules of the scheduling protocol, e.g. [I-D.ietf-jmap-calendars]
or [RFC5546].
3.1.8. method
method: String (optional). This is the iTIP [RFC5546] method, in
lowercase. This MUST only be present if the JSCalendar object
represents an iTIP scheduling message.
3.2. What and Where Properties
3.2.1. title
title: String (optional; default: empty String). This is a short
summary of the object.
3.2.2. description
description: String (optional; default: empty String). This is a
longer-form text description of the object. The content is
formatted according to the "descriptionContentType" property.
3.2.3. descriptionContentType
descriptionContentType: String (optional; default: "text/plain"). This
describes the media type [RFC6838] of the contents of the
"description" property. Media types MUST be subtypes of type
"text" and SHOULD be "text/plain" or "text/html" [MEDIATYPES].
They MAY include parameters, and the "charset" parameter value
MUST be "utf-8", if specified.
3.2.4. showWithoutTime
showWithoutTime: Boolean (optional; default: "false"). This
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indicates that the time is not important to display to the user
when rendering this calendar object. An example of this is an
event that conceptually occurs all day or across multiple days,
such as "New Year's Day" or "Italy Vacation". While the time
component is important for free-busy calculations and checking for
scheduling clashes, calendars may choose to omit displaying it
and/or display the object separately to other objects to enhance
the user's view of their schedule.
Such events are also commonly known as "all-day" events.
3.2.5. locations
locations: Id[Location] (optional). This is a map of location ids to
Location objects, representing locations associated with the
object.
A Location object has the following properties. It MUST have at
least one property other than the "@type" property.
@type: String.
This specifies the type of this object. This MUST be "Location",
if set.
name: String (optional).
This is the human-readable name or short description of the
location, such as an address.
locationTypes: String[Boolean] (optional).
This is a set of one or more location types that describe this
location. All types MUST be from the "Location Types Registry"
[LOCATIONTYPES], as defined in [RFC4589] . The set is represented
as a map, with the keys being the location types. The value for
each key in the map MUST be true.
coordinates: String (optional).
This is a "geo:" URI [RFC5870] for the location.
links: Id[Link] (optional).
This is a map of link ids to Link objects, representing external
resources associated with this location, for example, an image.
If there are no links, this MUST be omitted (rather than specified
as an empty set).
3.2.6. mainLocationId
mainLocationId: String (optional). This indicates which of the
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multiple entries in the "locations" property can be considered the
main location for the event or task. A client implementation MAY
choose to display this location more prominently. The main
location is undefined if this property is not set. If this
property is set, then its value MUST match a key in the
"locations" property and the "name" property of that main Location
object MUST be set.
3.2.7. virtualLocations
virtualLocations: Id[VirtualLocation] (optional). This is a map of
virtual location ids to VirtualLocation objects, representing
virtual locations, such as video conferences or chat rooms,
associated with the object.
A VirtualLocation object has the following properties.
@type: String.
This specifies the type of this object. This MUST be
"VirtualLocation", if set.
name: String (optional; default: empty String).
This is the human-readable name or short description of the
virtual location, such as an access code.
uri: String (mandatory).
This is a URI[RFC3986] that represents how to connect to this
virtual location.
This may be a telephone number (represented using the "tel:"
scheme, e.g., "tel:+1-555-555-5555") for a teleconference, a web
address for online chat, or any custom URI.
features: String[Boolean] (optional).
A set of features supported by this virtual location. The set is
represented as a map, with the keys being the feature. The value
for each key in the map MUST be true.
The feature MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8). Any value the client or
server doesn't understand should be treated the same as if this
feature is omitted.
audio: Audio conferencing
chat: Chat or instant messaging
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feed: Blog or atom feed
moderator: Provides moderator-specific features
phone: Phone conferencing
screen: Screen sharing
video: Video conferencing
3.2.8. links
links: Id[Link] (optional). This is a map of link ids to Link
objects, representing external resources associated with the
object.
Links with a rel of "enclosure" MUST be considered by the client
to be attachments for download.
Links with a rel of "describedby" MUST be considered by the client
to be alternative representations of the description.
Links with a rel of "icon" MUST be considered by the client to be
images that it may use when presenting the calendar data to a
user. The "display" property may be set to indicate the purpose
of this image.
3.2.9. locale
locale: String (optional). This is the language tag, as defined in
[RFC5646], that best describes the locale used for the text in the
calendar object, if known.
3.2.10. keywords
keywords: String[Boolean] (optional). This is a set of keywords or
tags that relate to the object. The set is represented as a map,
with the keys being the keywords. The value for each key in the
map MUST be true.
3.2.11. categories
categories: String[Boolean] (optional). This is a set of categories
that relate to the calendar object. The set is represented as a
map, with the keys being the categories specified as URIs. The
value for each key in the map MUST be true.
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In contrast to keywords, categories are typically structured. For
example, a vendor owning the domain "example.com" might define the
categories "http://example.com/categories/sports/american-
football" and "http://example.com/categories/music/r-b".
3.2.12. color
color: String (optional). This is a color clients MAY use when
displaying this calendar object. The value is a color name taken
from the set of names defined in Section 4.3 of [CSS3] or an RGB
value in six-digit hexadecimal notation, as defined in
Section 4.2.1 of [CSS3]. Values are case-insensitive.
3.3. Recurrence Properties
Some events and tasks occur at regular or irregular intervals.
Rather than having to copy the data for every occurrence, there can
be a base event with a rule to generate recurrences and/or overrides
that add extra dates or exceptions to the rule.
The recurrence set is the complete set of instances for an object.
It is generated by considering the following properties in order, all
of which are optional:
1. The "recurrenceRule" property (Section 3.3.3) generates a set of
extra date-times on which the object occurs.
2. The "recurrenceOverrides" property (Section 3.3.4) defines date-
times that are added or excluded to form the final set. (This
property may also contain changes to the object to apply to
particular instances.)
3.3.1. recurrenceId
recurrenceId: LocalDateTime (optional). If present, this JSCalendar
object represents one occurrence of a recurring JSCalendar object.
If present, the "recurrenceRule" and "recurrenceOverrides"
properties MUST NOT be present.
The value is a date-time either produced by the "recurrenceRule"
of the base event or added as a key to the "recurrenceOverrides"
property of the base event.
3.3.2. recurrenceIdTimeZone
recurrenceIdTimeZone: TimeZoneId (optional). Identifies the time
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zone of the main JSCalendar object, of which this JSCalendar
object is a recurrence instance. It MUST NOT be set if the
"recurrenceId" property is not set.
3.3.3. recurrenceRule
recurrenceRule: RecurrenceRule (optional). This a recurrence rule (a
repeating pattern) for recurring calendar objects.
An Event recurs by applying the recurrence rule to the "start"
date-time.
A Task recurs by applying the recurrence rule to the "start" date-
time, if defined; otherwise, it recurs by the "due" date-time, if
defined. If the task defines neither a "start" nor "due" date-
time, it MUST NOT define a "recurrenceRule" property.
A RecurrenceRule object is a JSON object mapping of a RECUR value
type in iCalendar [RFC5545] [RFC7529] and has the same semantics. It
has the following properties:
@type: String.
This specifies the type of this object. This MUST be
"RecurrenceRule", if set.
frequency: String (mandatory).
This is the time span covered by each iteration of this recurrence
rule (see Section 3.3.3.1 for full semantics). This MUST be one
of the following values:
* yearly
* monthly
* weekly
* daily
* hourly
* minutely
* secondly
This is the FREQ part from iCalendar, converted to lowercase.
interval: UnsignedInt (optional; default: 1).
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This is the interval of iteration periods at which the recurrence
repeats. If included, it MUST be an integer >= 1.
This is the INTERVAL part from iCalendar.
rscale: String (optional; default: "gregorian").
This is the calendar system in which this recurrence rule
operates, in lowercase. This MUST be either a CLDR-registered
calendar system name [CLDR] or a vendor-specific value (see
Section 1.8).
This is the RSCALE part from iCalendar RSCALE [RFC7529], converted
to lowercase.
skip: String (optional; default: "omit").
This is the behavior to use when the expansion of the recurrence
produces invalid dates. This property only has an effect if the
"frequency" is "yearly" or "monthly". It MUST be one of the
following values:
* omit
* backward
* forward
This is the SKIP part from iCalendar RSCALE [RFC7529], converted
to lowercase.
firstDayOfWeek: String (optional; default: "mo").
This is the day on which the week is considered to start,
represented as a lowercase, abbreviated, and two-letter English
day of the week. If included, it MUST be one of the following
values:
* mo
* tu
* we
* th
* fr
* sa
* su
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This is the WKST part from iCalendar.
byDay: NDay[] (optional).
These are days of the week on which to repeat. An "NDay" object
has the following properties:
@type: String.
This specifies the type of this object. This MUST be "NDay",
if set.
day: String (mandatory).
This is a day of the week on which to repeat; the allowed
values are the same as for the "firstDayOfWeek" property of the
RecurrenceRule.
This is the day of the week of the BYDAY part in iCalendar,
converted to lowercase.
nthOfPeriod: Int (optional).
If present, rather than representing every occurrence of the
weekday defined in the "day" property, it represents only a
specific instance within the recurrence period. The value can
be positive or negative but MUST NOT be zero. A negative
integer means the nth-last occurrence within that period (i.e.,
-1 is the last occurrence, -2 the one before that, etc.).
This is the ordinal part of the BYDAY value in iCalendar (e.g.,
1 or -3).
byMonthDay: Int[] (optional).
These are the days of the month on which to repeat. Valid values
are between 1 and the maximum number of days any month may have in
the calendar given by the "rscale" property and the negative
values of these numbers. For example, in the Gregorian calendar,
valid values are 1 to 31 and -31 to -1. Negative values offset
from the end of the month. The array MUST have at least one entry
if included.
This is the BYMONTHDAY part in iCalendar.
byMonth: String[] (optional).
These are the months in which to repeat. Each entry is a string
representation of a number, starting from "1" for the first month
in the calendar (e.g., "1" means January with the Gregorian
calendar), with an optional "L" suffix (see [RFC7529]) for leap
months (this MUST be uppercase, e.g., "3L"). The array MUST have
at least one entry if included.
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This is the BYMONTH part from iCalendar.
byYearDay: Int[] (optional).
These are the days of the year on which to repeat. Valid values
are between 1 and the maximum number of days any year may have in
the calendar given by the "rscale" property and the negative
values of these numbers. For example, in the Gregorian calendar,
valid values are 1 to 366 and -366 to -1. Negative values offset
from the end of the year. The array MUST have at least one entry
if included.
This is the BYYEARDAY part from iCalendar.
byWeekNo: Int[] (optional).
These are the weeks of the year in which to repeat. Valid values
are between 1 and the maximum number of weeks any year may have in
the calendar given by the "rscale" property and the negative
values of these numbers. For example, in the Gregorian calendar,
valid values are 1 to 53 and -53 to -1. The array MUST have at
least one entry if included.
This is the BYWEEKNO part from iCalendar.
byHour: UnsignedInt[] (optional).
These are the hours of the day in which to repeat. Valid values
are 0 to 23. The array MUST have at least one entry if included.
This is the BYHOUR part from iCalendar.
byMinute: UnsignedInt[] (optional).
These are the minutes of the hour in which to repeat. Valid
values are 0 to 59. The array MUST have at least one entry if
included.
This is the BYMINUTE part from iCalendar.
bySecond: UnsignedInt[] (optional).
These are the seconds of the minute in which to repeat. Valid
values are 0 to 60. The array MUST have at least one entry if
included.
This is the BYSECOND part from iCalendar.
bySetPosition: Int[] (optional).
These are the occurrences within the recurrence interval to
include in the final results. Negative values offset from the end
of the list of occurrences. The array MUST have at least one
entry if included. This is the BYSETPOS part from iCalendar.
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count: UnsignedInt (optional).
This is the number of occurrences at which to range-bound the
recurrence. This MUST NOT be included if an "until" property is
specified.
This is the COUNT part from iCalendar.
until: LocalDateTime (optional).
This is the date-time at which to finish recurring. The last
occurrence is on or before this date-time. This MUST NOT be
included if a "count" property is specified. Note that if not
specified otherwise for a specific JSCalendar object, this date is
to be interpreted in the time zone specified in the JSCalendar
object's "timeZone" property.
This is the UNTIL part from iCalendar.
3.3.3.1. Interpreting Recurrence Rules
A recurrence rule specifies a set of date-times for recurring
calendar objects. A recurrence rule has the following semantics.
Note that wherever "year", "month", or "day of month" is used, this
is within the calendar system given by the "rscale" property, which
defaults to "gregorian" if omitted.
1. A set of candidates is generated. This is every second within a
period defined by the "frequency" property value:
yearly: every second from midnight on the first day of a year
(inclusive) to midnight the first day of the following year
(exclusive).
If "skip" is not "omit", the calendar system has leap months,
and there is a "byMonth" property, generate candidates for the
leap months, even if they don't occur in this year.
If "skip" is not "omit" and there is a "byMonthDay" property,
presume each month has the maximum number of days any month
may have in this calendar system when generating candidates,
even if it's more than this month actually has.
monthly: every second from midnight on the first day of a month
(inclusive) to midnight on the first of the following month
(exclusive).
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If "skip" is not "omit" and there is a "byMonthDay" property,
presume the month has the maximum number of days any month may
have in this calendar system when generating candidates, even
if it's more than this month actually has.
weekly: every second from midnight (inclusive) on the first day
of the week (as defined by the "firstDayOfWeek" property or
Monday if omitted) to midnight seven days later (exclusive).
daily: every second from midnight at the start of the day
(inclusive) to midnight at the end of the day (exclusive).
hourly: every second from the beginning of the hour (inclusive)
to the beginning of the next hour (exclusive).
minutely: every second from the beginning of the minute
(inclusive) to the beginning of the next minute (exclusive).
secondly: only the second itself.
2. Each date-time candidate is compared against all of the byX
properties of the rule except "bySetPosition". If any property
in the rule does not match the date-time, the date-time is
eliminated. Each byX property is an array; the date-time matches
the property if it matches any of the values in the array. The
properties have the following semantics:
byMonth: The date-time is in the given month.
byWeekNo: The date-time is in the nth week of the year.
Negative numbers mean the nth last week of the year. This
corresponds to weeks according to week numbering, as defined
in ISO.8601.2004, with a week defined as a seven-day period,
starting on the "firstDayOfWeek" property value or Monday if
omitted. Week number one of the calendar year is the first
week that contains at least four days in that calendar year.
If the date-time is not valid (this may happen when generating
candidates with a "skip" property in effect), it is always
eliminated by this property.
byYearDay: The date-time is on the nth day of year. Negative
numbers mean the nth last day of the year.
If the date-time is not valid (this may happen when generating
candidates with a "skip" property in effect), it is always
eliminated by this property.
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byMonthDay: The date-time is on the given day of the month.
Negative numbers mean the nth last day of the month.
byDay: The date-time is on the given day of the week. If an
"nthOfPeriod" property is present, the date-time must be the
nth occurrence of that day of the week within the year (if
"frequency" is yearly AND no "byMonth" property exists on the
rule) or month (otherwise). Negative numbers mean the nth
last occurrence within that period.
byHour: The date-time has the given hour value.
byMinute: The date-time has the given minute value.
bySecond: The date-time has the given second value.
If a "skip" property is defined and is not "omit", there may be
candidates that do not correspond to valid dates (e.g., February
31st in the Gregorian calendar). In this case, the properties
MUST be considered in the order above, and:
1. After applying the "byMonth" filter, if the candidate's month
is invalid for the given year, increment it (if "skip" is
"forward") or decrement it (if "skip" is "backward") until a
valid month is found, incrementing/decrementing the year as
well if passing through the beginning/end of the year. This
only applies to calendar systems with leap months.
2. After applying the "byMonthDay" filter, if the day of the
month is invalid for the given month and year, change the
date to the first day of the next month (if "skip" is
"forward") or the last day of the current month (if "skip" is
"backward").
3. If any valid date produced after applying the skip is already
a candidate, eliminate the duplicate. (For example, after
adjusting, February 30th and February 31st would both become
the same "real" date, so one is eliminated as a duplicate.)
3. If a "bySetPosition" property is included, this is now applied to
the ordered list of remaining dates. This property specifies the
indexes of date-times to keep; all others should be eliminated.
Negative numbers are indexed from the end of the list, with -1
being the last item, -2 the second from last, etc.
4. Any date-times before the start date of the event are eliminated
(see below for why this might be needed).
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5. If a "skip" property is included and is not "omit", eliminate any
date-times that have already been produced by previous iterations
of the algorithm. (This is not possible if "skip" is "omit".)
6. If further dates are required (we have not reached the until date
or count limit), skip the next (interval - 1) sets of candidates,
then continue from step 1.
When determining the set of occurrence dates for an event or task,
the following extra rules must be applied:
1. The initial date-time to which the rule is applied (the "start"
date-time for events or the "start" or "due" date-time for tasks)
is always the first occurrence in the expansion (and is counted
if the recurrence is limited by a "count" property), even if it
would normally not match the rule.
2. The first set of candidates to consider is that which would
contain the initial date-time. This means the first set may
include candidates before the initial date-time; such candidates
are eliminated from the results in step 4 of the list above.
3. The following properties MUST be implicitly added to the rule
under the given conditions:
* If "frequency" is not "secondly" and there is no "bySecond"
property, add a "bySecond" property with the sole value being
the seconds value of the initial date-time.
* If "frequency" is not "secondly" or "minutely" and there is no
"byMinute" property, add a "byMinute" property with the sole
value being the minutes value of the initial date-time.
* If "frequency" is not "secondly", "minutely", or "hourly" and
there is no "byHour" property, add a "byHour" property with
the sole value being the hours value of the initial date-time.
* If "frequency" is "weekly" and there is no "byDay" property,
add a "byDay" property with the sole value being the day of
the week of the initial date-time.
* If "frequency" is "monthly" and there is no "byDay" property
and no "byMonthDay" property, add a "byMonthDay" property with
the sole value being the day of the month of the initial date-
time.
* If "frequency" is "yearly" and there is no "byYearDay"
property:
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- If there are no "byMonth" or "byWeekNo" properties, and
either there is a "byMonthDay" property or there is no
"byDay" property, add a "byMonth" property with the sole
value being the month of the initial date-time.
- If there are no "byMonthDay", "byWeekNo", or "byDay"
properties, add a "byMonthDay" property with the sole value
being the day of the month of the initial date-time.
- If there is a "byWeekNo" property and no "byMonthDay" or
"byDay" properties, add a "byDay" property with the sole
value being the day of the week of the initial date-time.
3.3.4. recurrenceOverrides
recurrenceOverrides: LocalDateTime[PatchObject] (optional). This
maps recurrence ids (the date-time produced by the recurrence
rule) to the overridden properties of the recurrence instance.
If the recurrence id does not match a date-time from the
recurrence rule (or no rule is specified), it is to be treated as
an additional occurrence (like an RDATE from iCalendar). The
patch object may often be empty in this case.
If the occurrence generated by the recurrence id shall be omitted
from the final set of recurrences (like an EXDATE from iCalendar),
then the patch object MUST be a JSON object with a single member.
The member name MUST be "excluded", the member value MUST be true.
The JSON object MUST NOT contain any other members.
By default, an occurrence inherits all properties from the main
object except the start (or due) date-time, which is shifted to
match the recurrence id LocalDateTime. However, individual
properties of the occurrence can be modified by a patch or
multiple patches. It is valid to patch the "start" property
value, and this patch takes precedence over the value generated
from the recurrence id. Both the recurrence id as well as the
patched "start" date-time may occur before the original JSCalendar
object's "start" or "due" date.
A pointer in the PatchObject MUST be ignored if it either exactly
matches one of:
* @type
* method
* organizerCalendarAddress
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* participants/*/"calendarAddress"
* privacy
* prodId
* recurrenceId
* recurrenceIdTimeZone
* sentBy
* uid
or if the first reference token of the pointer matches one of:
* recurrenceOverrides
* recurrenceRule
* relatedTo
where the "*" character stands for a JSON pointer reference token
having any value.
3.4. Sharing and Scheduling Properties
3.4.1. priority
priority: Int (optional; default: 0). This specifies a priority for
the calendar object. This may be used as part of scheduling
systems to help resolve conflicts for a time period.
The priority is specified as an integer in the range 0 to 9. A
value of 0 specifies an undefined priority, for which the
treatment will vary by situation. A value of 1 is the highest
priority. A value of 2 is the second highest priority.
Subsequent numbers specify a decreasing ordinal priority. A value
of 9 is the lowest priority. Other integer values are reserved
for future use.
3.4.2. freeBusyStatus
freeBusyStatus: String (optional; default: "busy"). This specifies
how this calendar object should be treated when calculating free-
busy state. This MUST be one of the following values, another
value registered in the IANA "JSCalendar Enum Values" registry, or
a vendor-specific value (see Section 1.8):
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free: The object should be ignored when calculating whether the
user is busy.
busy: The object should be included when calculating whether the
user is busy.
3.4.3. privacy
privacy: String (optional; default: "public"). Calendar objects are
normally collected together and may be shared with other users.
The "privacy" property allows the object owner to indicate that it
should not be shared or should only have the time information
shared but the details withheld. Enforcement of the restrictions
indicated by this property is up to the API via which this object
is accessed.
This property MUST NOT affect the information sent to scheduled
participants; it is only interpreted by protocols that share the
calendar objects belonging to one user with other users.
The value of the "privacy" property MUST be one of the following
values, another value registered in the IANA "JSCalendar Enum
Values" registry, or a vendor-specific value (see Section 1.8).
Any value the client or server doesn't understand should be
preserved but treated as equivalent to "private".
public: The full details of the object are visible to those whom
the object's calendar is shared with.
private: The details of the object are hidden; only the basic
time and metadata are shared. The following properties MAY be
shared; any other properties MUST NOT be shared:
* @type
* created
* due
* duration
* estimatedDuration
* freeBusyStatus
* privacy
* recurrenceId
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* recurrenceIdTimeZone
* "recurrenceOverrides" (Only patches that apply to another
permissible property are allowed to be shared.)
* recurrenceRule
* sequence
* showWithoutTime
* start
* timeZone
* uid
* updated
* version
secret: The object is hidden completely (as though it did not
exist) when the calendar this object is in is shared.
3.4.4. organizerCalendarAddress
organizerCalendarAddress: String (optional). This is a URI as
defined by [RFC3986] or any other IANA-registered form for a URI.
It is the same as the CAL-ADDRESS value of an iCalendar ORGANIZER
property [RFC5545] (Section 3.8.4.3) — it globally identifies a
particular organizer, even across different calendaring objects.
If this property is set then at least one Participant object in
the "participants" property MUST have the "calendarAddress"
property set.
3.4.5. sentBy
Type: "String" (optional)
This is the email address in the "From" header of the email in which
this calendar object was received. This is only relevant if the
calendar object is received via iMIP or as an attachment to a
message. The value MUST be a valid "addr-spec" value as defined in
Section 3.4.1 of [RFC5322]. If this property is set, then the
"organizerCalendarAddress" property MUST be set.
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3.4.6. participants
participants: Id[Participant] (optional). This is a map of
participant ids to participants, describing their participation in
the calendar object. If this property is set and any participant
has the "calendarAddress" property set, then the
"organizerCalendarAddress" property of the calendar object MUST be
set.
A Participant object has the following properties:
@type: String.
This specifies the type of this object. This MUST be
"Participant", if set.
name: String (optional).
This is the display name of the participant (e.g., "Joe Bloggs").
email: String (optional).
This is the email address to use to contact the participant or,
for example, match with an address book entry. If set, the value
MUST be a valid "addr-spec" value as defined in Section 3.4.1 of
[RFC5322]. If this property is set, then the "calendarAddress"
property MUST be set.
description: String (optional).
This is a description of this participant. For example, this may
include more information about their role in the event or how best
to contact them.
descriptionContentType: String (optional).
This describes the media type of the contents of the "description"
property. Its requirements are specified in Section 3.2.3. If
this property is set, then the "description" property MUST be set.
calendarAddress: String (optional).
This is a URI as defined by [RFC3986] or any other IANA-registered
form for a URI. It is the same as the CAL-ADDRESS value of an
iCalendar ATTENDEE property [RFC5545] (Section 3.8.4.1) or
ORGANIZER property [RFC5545] (Section 3.8.4.3) — it globally
identifies a particular participant, even across different
calendaring objects.
kind: String (optional).
This is what kind of entity this participant is, if known. If
this property is set, then the "calendarAddress" property MUST be
set. The value MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
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vendor-specific value (see Section 1.8). Any value the client or
server doesn't understand should be treated the same as if this
property is omitted.
individual: a single person
group: a collection of people invited as a whole
location: a physical location that needs to be scheduled, e.g., a
conference room
resource: a non-human resource other than a location, such as a
projector
roles: String[Boolean] (optional).
This is a set of roles that this participant fulfills. If this
property is set, then the "calendarAddress" property MUST be set
and at least one role MUST be specified for the participant. The
keys in the set MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
owner: The participant is an owner of the calendar object. This
signifies they can make changes that affect all participants
(for example, rescheduling the calendar object, adding and
removing participants and roles). The presence of this role
only is indicative, its semantics are subject to the
calendaring exchange protocol being used. See
[I-D.ietf-jmap-calendars] for an example for making use of this
role.
optional: The participant's involvement with the event is
optional.
informational: The participant is copied for informational
reasons and is not expected to attend.
chair: The participant is in charge of the event/task when it
occurs.
required: The participant is required to be present at the event.
The value for each key in the map MUST be true. It is expected
that no more than one of the roles "required", "optional",
"informational" and "chair" be present; if more than one are
given, they take precedence as follows: "chair" over "required",
either of them over "optional", all of them over "informational".
Roles that are unknown to the implementation MUST be preserved.
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participationStatus: String (optional; default: "needs-action").
This is the participation status, if any, of this participant. If
this property is set, then the "calendarAddress" property MUST be
set.
The value MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
needs-action: No status has yet been set by the participant.
accepted: The invited participant will participate.
declined: The invited participant will not participate.
tentative: The invited participant may participate.
delegated: The invited participant has delegated their attendance
to another participant, as specified in the "delegatedTo"
property.
expectReply: Boolean (optional; default: "false").
If true, the organizer is expecting the participant to notify them
of their participation status. If this property is set, then the
"calendarAddress" property MUST be set.
sentBy: String (optional).
This is the email address in the "From" header of the email that
last updated this participant via iMIP. If this property is set,
then the "calendarAddress" property MUST be set. This SHOULD only
be set if the email address is different to that in the mailto URI
of this participant's "calendarAddress" property (i.e., the
response was received from a different address to that which the
invitation was sent to). If set, the value MUST be a valid "addr-
spec" value as defined in Section 3.4.1 of [RFC5322] .
delegatedTo: String[Boolean] (optional).
This is the set of participants that this participant has
delegated their participation to. If this property is set, then
the "calendarAddress" property MUST be set. Each key in the set
MUST be a URI according to the definition of the "calendarAddress"
property. The value for each key in the map MUST be true. If
there are no delegates, this MUST be omitted (rather than
specified as an empty set).
delegatedFrom: String[Boolean] (optional).
This is a set of participants that this participant is acting as a
delegate for. If this property is set, then the "calendarAddress"
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property MUST be set. Each key in the set MUST be a URI according
to the definition of the "calendarAddress" property. The value
for each key in the map MUST be true. If there are no delegators,
this MUST be omitted (rather than specified as an empty set).
memberOf: Id[Boolean] (optional).
This is a set of group participants that were invited to this
calendar object, which caused this participant to be invited due
to their membership in the group(s). If this property is set,
then the "calendarAddress" property MUST be set. Each key in the
set MUST be a URI according to the definition of the
"calendarAddress" property. The value for each key in the map
MUST be true. If there are no groups, this MUST be omitted
(rather than specified as an empty set).
links: Id[Link] (optional).
This is a map of link ids to Link objects, representing external
resources associated with this participant, for example, an image.
If there are no links, this MUST be omitted (rather than specified
as an empty set).
progress: String (optional)
This property only is defined for Participant objects within a
Task object, it otherwise MUST NOT be set. It represents the
progress of the participant for this task. If this property is
set, then the "calendarAddress" property MUST be set and the
"participationStatus" of this participant MUST be "accepted". The
property value MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
in-process: The participant is in process of contributing to the
task.
completed: The participant successfully completed contributing to
the task.
failed: The participant could not complete their contribution to
the task.
percentComplete: UnsignedInt (optional; only allowed for
participants of a Task).
This represents the percent completion of the participant for this
task. The property value MUST be a positive integer between 0 and
100.
3.5. Alerts Properties
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3.5.1. alerts
alerts: Id[Alert] (optional). This is a map of alert ids to Alert
objects, representing alerts/reminders to display or send to the
user for this calendar object.
An Alert object has the following properties:
@type: String.
This specifies the type of this object. This MUST be "Alert", if
set.
trigger: OffsetTrigger|AbsoluteTrigger|UnknownTrigger (mandatory;
defaultType: OffsetTrigger).
This defines when to trigger the alert. New types may be defined
in future documents.
An "OffsetTrigger" object has the following properties:
@type: String.
This specifies the type of this object. This MUST be
"OffsetTrigger", if set.
offset: SignedDuration (mandatory).
This defines the offset at which to trigger the alert relative
to the time property defined in the "relativeTo" property of
the alert. Negative durations signify alerts before the time
property; positive durations signify alerts after the time
property.
relativeTo: String (optional; default: "start" ).
This specifies the time property that the alert offset is
relative to. The value MUST be one of the following:
start: triggers the alert relative to the start of the
calendar object
end: triggers the alert relative to the end/due time of the
calendar object
An "AbsoluteTrigger" object has the following properties:
@type: String.
This specifies the type of this object. This MUST be
"AbsoluteTrigger".
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when: UTCDateTime (mandatory).
This defines a specific UTC date-time when the alert is
triggered.
An "UnknownTrigger" object is an object that contains an "@type"
property whose value is not recognized (i.e., not "OffsetTrigger"
or "AbsoluteTrigger" ) plus zero or more other properties. This
is for compatibility with client extensions and future
specifications. Implementations SHOULD NOT trigger for trigger
types they do not understand but MUST preserve them.
acknowledged: UTCDateTime (optional).
This records when an alert was last acknowledged. This is set
when the user has dismissed the alert; other clients that sync
this property SHOULD automatically dismiss or suppress duplicate
alerts (alerts with the same alert id that triggered on or before
this date-time).
For a recurring calendar object, setting the "acknowledged"
property MUST NOT add a new override to the "recurrenceOverrides"
property. If the alert is not already overridden, the
"acknowledged" property MUST be set on the alert in the base
event/task.
Certain kinds of alert action may not provide feedback as to when
the user sees them, for example, email-based alerts. For those
kinds of alerts, this property MUST be set immediately when the
alert is triggered and the action is successfully carried out.
relatedTo: String[Relation] (optional).
This relates this alert to other alerts in the same JSCalendar
object. Each key in the map is the key of an Alert object in the
"alerts" property. The value defines the type of the relation.
In addition to the relation values defined in Section 1.5.10, the
following key is allowed:
snooze: The linked alert is snoozed by this alert.
If the user wishes to snooze an alert, the application MUST create
an alert to trigger after snoozing. This new snooze alert MUST
set a "snooze" relation to the identifier of the original alert.
action: String (optional; default: "display" ).
This describes how to alert the user.
The value MUST be at most one of the following values, a value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
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display: The alert should be displayed as appropriate for the
current device and user context.
email: The alert should trigger an email sent out to the user,
notifying them of the alert. This action is typically only
appropriate for server implementations.
3.6. Time Zone Properties
3.6.1. timeZone
timeZone: TimeZoneId (optional). This identifies the time zone the
object is scheduled in. If omitted, the object is not scheduled
in a particular time zone but in "floating time".
4. Type-Specific JSCalendar Properties
4.1. Event Properties
In addition to the common JSCalendar object properties (Section 3),
an Event has the following properties:
4.1.1. start
start: LocalDateTime (mandatory). This is the date/time the event
starts in the event's time zone (as specified in the "timeZone"
property, see Section 3.6.1).
4.1.2. duration
duration: Duration (optional; default: "PT0S"). This is the zero or
positive duration of the event in the event's start time zone.
The end time of an event can be found by adding the duration to
the event's start time.
4.1.3. endTimeZone
endTimeZone: TimeZoneId (optional). This identifies the time zone in
which this event ends, for cases where the start and time zones of
the event differ (e.g., a transcontinental flight). If this
property is not set, then the event starts and ends in the same
time zone. This property MUST NOT be set if the "timeZone"
property is not set.
4.1.4. status
status: String (optional; default: "confirmed"). This is the
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scheduling status ( Section 3.4) of an Event. If set, it MUST be
one of the following values, another value registered in the IANA
"JSCalendar Enum Values" registry, or a vendor-specific value (see
Section 1.8):
confirmed: indicates the event is definitely happening
cancelled: indicates the event has been cancelled
tentative: indicates the event may happen
4.2. Task Properties
In addition to the common JSCalendar object properties (Section 3), a
Task has the following properties.
If the "timeZone" property value is not set or the "showWithoutTime"
property value is "true", then at least one of the "due" and "start"
properties MUST be set.
4.2.1. due
due: LocalDateTime (optional). This is the date/time the task is due
in the task's time zone.
4.2.2. start
start: LocalDateTime (optional). This the date/time the task should
start in the task's time zone. This MUST be set if the
"recurrenceRule" or "recurrenceId" properties are set.
4.2.3. estimatedDuration
estimatedDuration: Duration (optional). This specifies the estimated
positive duration of time the task takes to complete.
4.2.4. percentComplete
percentComplete: UnsignedInt (optional). This represents the percent
completion of the task overall. The property value MUST be a
positive integer between 0 and 100.
4.2.5. progress
progress: String (optional). This defines the progress of this task.
If omitted, the default progress ( Section 3.4) of a Task is
defined as follows (in order of evaluation):
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completed: if the "progress" property value of all participants
is "completed"
failed: if at least one "progress" property value of a
participant is "failed"
in-process: if at least one "progress" property value of a
participant is "in-process"
needs-action: if none of the other criteria match
If set, it MUST be one of the following values, another value
registered in the IANA "JSCalendar Enum Values" registry, or a
vendor-specific value (see Section 1.8):
needs-action: indicates the task needs action
in-process: indicates the task is in process
completed: indicates the task is completed
failed: indicates the task failed
cancelled: indicates the task was cancelled
4.3. Group Properties
Group supports the following common JSCalendar properties (Section 3)
:
* @type
* categories
* color
* created
* description
* descriptionContentType
* keywords
* links
* locale
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* prodId
* title
* uid
* updated
* version
In addition, the following Group-specific properties are supported:
4.3.1. entries
entries: (Task|Event)[] (mandatory). This is a collection of group
members. Implementations MUST ignore entries of unknown type.
4.3.2. source
source: String (optional). This is the source from which updated
versions of this group may be retrieved. The value MUST be a URI.
5. Examples
The following examples illustrate several aspects of the JSCalendar
data model and format. The examples may omit mandatory or additional
properties, which is indicated by a placeholder property with key
"...". While most of the examples use calendar event objects, they
are also illustrative for tasks.
5.1. Simple Event
This example illustrates a simple one-time event. It specifies a
one-time event that begins on January 15, 2020 at 1 pm New York local
time and ends after 1 hour.
{
"@type": "Event",
"version": "2.0",
"uid": "a8df6573-0474-496d-8496-033ad45d7fea",
"updated": "2020-01-02T18:23:04Z",
"title": "Some event",
"start": "2020-01-15T13:00:00",
"timeZone": "America/New_York",
"duration": "PT1H"
}
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5.2. Simple Task
This example illustrates a simple task for a plain to-do item.
{
"@type": "Task",
"version": "2.0",
"uid": "2a358cee-6489-4f14-a57f-c104db4dc2f2",
"updated": "2020-01-09T14:32:01Z",
"title": "Do something"
}
5.3. Simple Group
This example illustrates a simple calendar object group that contains
an event and a task.
{
"@type": "Group",
"version": "2.0",
"uid": "bf0ac22b-4989-4caf-9ebd-54301b4ee51a",
"updated": "2020-01-15T18:00:00Z",
"title": "A simple group",
"entries": [{
"@type": "Event",
"uid": "a8df6573-0474-496d-8496-033ad45d7fea",
"updated": "2020-01-02T18:23:04Z",
"title": "Some event",
"start": "2020-01-15T13:00:00",
"timeZone": "America/New_York",
"duration": "PT1H"
},
{
"@type": "Task",
"uid": "2a358cee-6489-4f14-a57f-c104db4dc2f2",
"updated": "2020-01-09T14:32:01Z",
"title": "Do something"
}]
}
5.4. All-Day Event
This example illustrates an event for an international holiday. It
specifies an all-day event on April 1 that occurs every year since
the year 1900.
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{
"...": "",
"title": "April Fool's Day",
"showWithoutTime": true,
"start": "1900-04-01T00:00:00",
"duration": "P1D",
"recurrenceRule": {
"frequency": "yearly"
}
}
5.5. Task with a Due Date
This example illustrates a task with a due date. It is a reminder to
buy groceries before 6 pm Vienna local time on January 19, 2020. The
calendar user expects to need 1 hour for shopping.
{
"...": "",
"title": "Buy groceries",
"due": "2020-01-19T18:00:00",
"timeZone": "Europe/Vienna",
"estimatedDuration": "PT1H"
}
5.6. Event with End Time Zone
This example illustrates the use of end time zones by use of an
international flight. The flight starts on April 1, 2020 at 9 am in
Berlin local time. The duration of the flight is scheduled at 10
hours 30 minutes. The time at the flight's destination is in the
same time zone as Tokyo. Calendar clients could use the end time
zone to display the arrival time in Tokyo local time and highlight
the time zone difference of the flight. The location names can serve
as input for navigation systems. The "mainLocationId" property
indicates the start location.
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{
"...": "",
"title": "Flight XY51 to Tokyo",
"start": "2020-04-01T09:00:00",
"timeZone": "Europe/Berlin",
"endTimeZone": "Asia/Tokyo",
"duration": "PT10H30M",
"mainLocationId": "1",
"locations": {
"1": {
"name": "Frankfurt Airport (FRA)"
},
"2": {
"name": "Narita International Airport (NRT)"
}
}
}
5.7. Floating-Time Event (with Recurrence)
This example illustrates the use of floating time. Since January 1,
2020, a calendar user blocks 30 minutes every day to practice yoga at
7 am local time in whatever time zone the user is located on that
date.
{
"...": "",
"title": "Yoga",
"start": "2020-01-01T07:00:00",
"duration": "PT30M",
"recurrenceRule": {
"frequency": "daily"
}
}
5.8. Event with Physical and Virtual Location
This example illustrates an event that happens at both a physical and
a virtual location. Fans can see a live concert on premises or
online. In addition to the main event location, the event contains
an additional location for a nearby parking garage.
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{
"...": "",
"title": "Live from Music Bowl: The Band",
"description": "Go see the biggest music event ever!",
"locale": "en",
"start": "2020-07-04T17:00:00",
"timeZone": "America/New_York",
"duration": "PT3H",
"mainLocationId": "c0503d30-8c50-4372-87b5-7657e8e0fedd",
"locations": {
"c0503d30-8c50-4372-87b5-7657e8e0fedd": {
"name": "The Music Bowl",
"description": "Music Bowl, Central Park, New York",
"coordinates": "geo:40.7829,-73.9654"
},
"ee42e41e-1046-4489-9760-c0b85f0dc176": {
"name": "BAZ Parking, 9 West 57th Street, New York",
"coordinates": "geo:40.7637,-73.9748",
"locationTypes": {
"parking": true
}
}
},
"virtualLocations": {
"vloc1": {
"name": "Free live Stream from Music Bowl",
"uri": "https://stream.example.com/the_band_2020"
}
}
}
5.9. Recurring Event with Overrides
This example illustrates the use of recurrence overrides. A math
course at a university is held for the first time on January 8, 2020
at 9 am London time and occurs every week until June 24, 2020. Each
lecture lasts for one hour and 30 minutes and is located at the
Mathematics department. This event has exceptional occurrences: at
the last occurrence of the course is an exam, which lasts for 2 hours
and starts at 10 am. Also, the location of the exam differs from the
usual location. On April 1, no course is held. On January 7 at 2
pm, there is an optional introduction course, which occurs before the
first regular lecture.
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{
"...": "",
"title": "Calculus I",
"start": "2020-01-08T09:00:00",
"timeZone": "Europe/London",
"duration": "PT1H30M",
"locations": {
"mlab": {
"name": "Math lab room 1",
"description": "Math Lab I, Department of Mathematics"
}
},
"recurrenceRule": {
"frequency": "weekly",
"until": "2020-06-24T09:00:00"
},
"recurrenceOverrides": {
"2020-01-07T14:00:00": {
"title": "Introduction to Calculus I (optional)"
},
"2020-04-01T09:00:00": {
"excluded": true
},
"2020-06-25T09:00:00": {
"title": "Calculus I Exam",
"start": "2020-06-25T10:00:00",
"duration": "PT2H",
"locations": {
"auditorium": {
"name": "Big Auditorium",
"description": "Big Auditorium, Other Road"
}
}
}
}
}
5.10. Making a "This and Future" Change
Sometimes, you may want to make a change to a recurring event that
applies from a specific instance onwards. This cannot be represented
as a single JSCalendar object. Instead, you must duplicate the
event, modifying the recurrence rule of the original so it finishes
before the split point, and the duplicate so it starts at the split
point. A "next" and "first" relation must be set on the new objects
respectively, as per Section 3.1.3.
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This example shows two JSCalendar objects, representing an event that
used to happen at 2pm on a Tuesday in Room 101, but moved in March to
3pm on a Wednesday in Room 202.
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{
"...": "",
"uid": "715ed4c5-3cf5-427f-927c-db40cdd63894",
"relatedTo": {
"32859916-af7a-4599-82ed-32a4315b4fe7": {
"relation": {
"next": true
}
}
},
"title": "Departmental meeting",
"start": "2025-01-07T14:00:00",
"timeZone": "Australia/Melbourne",
"duration": "PT1H",
"locations": {
"room": {
"name": "Room 101"
}
},
"recurrenceRule": {
"frequency": "weekly",
"until": "2025-02-25T14:00:00"
}
}
{
"...": "",
"uid": "32859916-af7a-4599-82ed-32a4315b4fe7",
"relatedTo": {
"715ed4c5-3cf5-427f-927c-db40cdd63894": : {
"relation": {
"first": true
}
}
},
"title": "Departmental meeting",
"start": "2025-03-05T15:00:00",
"timeZone": "Australia/Melbourne",
"duration": "PT1H",
"locations": {
"room": {
"name": "Room 202"
}
},
"recurrenceRule": {
"frequency": "weekly"
}
}
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5.11. Recurring Event with Participants
This example illustrates scheduled events. A team meeting occurs
every week since January 8, 2020 at 9 am Johannesburg time. The
event owner also chairs the event. Participants meet in a virtual
meeting room. A participant has accepted the invitation, but, on
March 4, 2020, they are unavailable and declined participation for
this occurrence.
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{
"...": "",
"title": "FooBar team meeting",
"start": "2020-01-08T09:00:00",
"timeZone": "Africa/Johannesburg",
"duration": "PT1H",
"virtualLocations": {
"0": {
"name": "ChatMe meeting room",
"uri": "https://chatme.example.com?id=1234567&pw=a8a24627b63d"
}
},
"recurrenceRule": {
"frequency": "weekly"
},
"organizerCalendarAddress":
"mailto:f245f875-7f63-4a5e-a2c8@schedule.example.com",
"participants": {
"dG9tQGZvb2Jhci5xlLmNvbQ": {
"name": "Tom Tool",
"email": "tom@foobar.example.com",
"calendarAddress": "mailto:tom@calendar.example.com",
"participationStatus": "accepted",
},
"em9lQGZvb2GFtcGxlLmNvbQ": {
"name": "Zoe Zelda",
"calendarAddress": "mailto:zoe@foobar.example.com",
"participationStatus": "accepted",
"roles": {
"owner": true,
"chair": true
}
}
},
"recurrenceOverrides": {
"2020-03-04T09:00:00": {
"participants/dG9tQGZvb2Jhci5xlLmNvbQ/participationStatus":
"declined"
}
}
}
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6. Security Considerations
Calendaring and scheduling information is very privacy sensitive. It
can reveal the social network of a user, location information of this
user and those in their social network, identity and credentials
information, and patterns of behavior of the user in both the
physical and cyber realm. Additionally, calendar events and tasks
can influence the physical location of a user or their cyber behavior
within a known time window. Its transmission and storage must be
done carefully to protect it from possible threats, such as
eavesdropping, replay, message insertion, deletion, modification, and
on-path attacks.
The data being stored and transmitted may be used in systems with
real-world consequences. For example, a home automation system may
turn an alarm on and off or a coworking space may charge money to the
organizer of an event that books one of their meeting rooms. Such
systems must be careful to authenticate all data they receive to
prevent them from being subverted and ensure the change comes from an
authorized entity.
This document only defines the data format; such considerations are
primarily the concern of the API or method of storage and
transmission of such files.
6.1. Expanding Recurrences
A recurrence rule may produce infinite occurrences of an event.
Implementations MUST handle expansions carefully to prevent
accidental or deliberate resource exhaustion.
Conversely, a recurrence rule may be specified that does not expand
to anything. It is not always possible to tell this through static
analysis of the rule, so implementations MUST be careful to avoid
getting stuck in infinite loops or otherwise exhausting resources
while searching for the next occurrence.
Events recur in the event's time zone. If the user is in a different
time zone, daylight saving transitions may cause an event that
normally occurs at, for example, 9 am to suddenly shift an hour
earlier. This may be used in an attempt to cause a participant to
miss an important meeting. User agents must be careful to translate
date-times correctly between time zones and may wish to call out
unexpected changes in the time of a recurring event.
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6.2. JSON Parsing
The security considerations of [RFC8259] apply to the use of JSON as
the data interchange format.
As for any serialization format, parsers need to thoroughly check the
syntax of the supplied data. JSON uses opening and closing tags for
several types and structures, and it is possible that the end of the
supplied data will be reached when scanning for a matching closing
tag; this is an error condition, and implementations need to stop
scanning at the end of the supplied data.
JSON also uses a string encoding with some escape sequences to encode
special characters within a string. Care is needed when processing
these escape sequences to ensure that they are fully formed before
the special processing is triggered, with special care taken when the
escape sequences appear adjacent to other (non-escaped) special
characters or adjacent to the end of data (as in the previous
paragraph).
If parsing JSON into a non-textual structured data format,
implementations may need to allocate storage to hold JSON string
elements. Since JSON does not use explicit string lengths, the risk
of denial of service due to resource exhaustion is small, but
implementations may still wish to place limits on the size of
allocations they are willing to make in any given context, to avoid
untrusted data causing excessive memory allocation.
6.3. URI Values
Several JSCalendar properties contain URIs as values, and processing
these properties requires extra care. Section 7 of [RFC3986]
discusses security risks related to URIs.
Fetching remote resources carries inherent risks. Connections must
only be allowed on well-known ports, using allowed protocols
(generally, just HTTP/HTTPS on their default ports). The URL must be
resolved externally and not allowed to access internal resources.
Connecting to an external source reveals IP (and therefore often
location) information.
A maliciously constructed JSCalendar object may contain a very large
number of URIs. In the case of published calendars with a large
number of subscribers, such objects could be widely distributed.
Implementations should be careful to limit the automatic fetching of
linked resources to reduce the risk of this being an amplification
vector for a denial-of-service attack.
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6.4. Spam
Calendar systems may receive JSCalendar files from untrusted sources,
in particular, as attachments to emails. This can be a vector for an
attacker to inject spam into a user's calendar. This may confuse,
annoy, and mislead users or overwhelm their calendar with bogus
events, preventing them from seeing legitimate ones.
Heuristic, statistical, or machine-learning-based filters can be
effective in filtering out spam. Authentication mechanisms, such as
DomainKeys Identified Mail (DKIM) [RFC6376], can help establish the
source of messages and associate the data with existing relationships
(such as an address book contact). However, misclassifications are
always possible and providing a mechanism for users to quickly
correct this is advised.
Confusable unicode characters may be used to trick a user into
trusting a JSCalendar file that appears to come from a known contact
but is actually from a similar-looking source controlled by an
attacker.
6.5. Duplication
It is important for calendar systems to maintain the UID of an event
when updating it to avoid an unexpected duplication of events.
Consumers of the data may not remove the previous version of the
event if it has a different UID. This can lead to a confusing
situation for the user, with many variations of the event and no
indication of which one is correct. Care must be taken by consumers
of the data to remove old events where possible to avoid an
accidental denial-of-service attack due to the volume of data.
6.6. Time Zones
Events recur in a particular time zone. When this differs from the
user's current time zone, it may unexpectedly cause an occurrence to
shift in time for that user due to a daylight savings change in the
event's time zone. A maliciously crafted event could attempt to
confuse users with such an event to ensure a meeting is missed.
7. IANA Considerations
IANA has created the "JSCalendar Properties", "JSCalendar Types" and
"JSCalendar Enum Values" registries, originally defined in [RFC8984].
This document updates some of the registry definitions and registry
contents. The following sections redefine all IANA considerations,
even if they are unchanged.
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7.1. Media Type Registration
[RFC8984] defined a media type for use with JSCalendar data formatted
in JSON. This section restates the original definition unchanged.
Type name: application
Subtype name: jscalendar+json
Required parameters: type
The "type" parameter conveys the type of the JSCalendar data in
the body part. The allowed parameter values correspond to the
"@type" property of the JSON-formatted JSCalendar object in the
body:
event: The "@type" property value MUST be "Event".
task: The "@type" property value MUST be "Task".
group: The "@type" property value MUST be "Group".
No other parameter values are allowed. The parameter MUST NOT
occur more than once.
Optional parameters: version
This parameter conveys the version of the JSCalendar data in the
body part. It MUST NOT occur more than once. If this parameter
is set, then the values of all JSCalendar "version"
(Section 7.4.2.4, Paragraph 11) properties in the body part MUST
match the parameter value.
Encoding considerations: This is the same as the encoding
considerations of application/json, as specified in Section 11 of
[RFC8259].
Security considerations: See Section 6 of this document.
Interoperability considerations: While JSCalendar is designed to
avoid ambiguities as much as possible, when converting objects
from other calendar formats to/from JSCalendar, it is possible
that differing representations for the same logical data or
ambiguities in interpretation might arise. The semantic
equivalence of two JSCalendar objects may be determined
differently by different applications, for example, where URL
values differ in case between the two objects.
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Published specification: draft-ietf-calext-jscalendarbis
Applications that use this media type: Applications that currently
make use of the text/calendar and application/calendar+json media
types can use this as an alternative. Similarly, applications
that use the application/json media type to transfer calendaring
data can use this to further specify the content.
Fragment identifier considerations: A JSON Pointer fragment
identifier may be used, as defined in [RFC6901], Section 6.
Additional information: Magic number(s): N/A
File extensions(s): N/A
Macintosh file type code(s): N/A
Person & email address to contact for further information:
calsify@ietf.org
Intended usage: COMMON
Restrictions on usage: N/A
Author: See the "Author's Address" section of this document.
Change controller: IETF
7.2. Registry Policy and Change Procedures
Registry assignments that introduce backwards-incompatible
(Section 1.9) changes require the JSCalendar major version to change;
other changes only require a change to the minor version. The
registry policy for assignments that require the JSCalendar major
version to change is Standards Action ([RFC8126], Section 4.9). The
registry policy for other assignments is Specification Required
([RFC8126], Section 4.6).
The designated expert (DE) decides if a major or minor version change
is required and assigns the new version to the "JSCalendar Version"
registry (Section 7.3). Version numbers increment by one, and a
major version change resets the minor version to zero. An assignment
may apply multiple changes and to more than one registry at once, in
which case a single version change is sufficient. If the registry
policy is Specification Required, then the DE may decide that it is
enough to document the new assignment in the Description item of the
respective registry.
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A registration MUST have an intended usage of "common", "reserved",
or "obsolete".
* A "common" usage denotes an item with shared semantics and syntax
across systems. Up-to-date systems MUST expect such items to
occur in JSCalendar data.
* A "reserved" usage reserves an item in the registry without
assigning semantics to avoid name collisions with future
extensions or protocol use. Implementations MUST NOT expect or
add items with such names outside the protocols or extensions that
use them; otherwise, any such JSCalendar data is invalid.
* An "obsolete" usage denotes an item that is no longer expected to
be added by up-to-date systems. A new assignment has probably
been defined, covering the obsolete item's semantics.
Implementations MUST expect such items to occur in JSCalendar data
up to the "Until Version" registry field, inclusively. They MUST
NOT add such items for any version after which the item got
obsolete; otherwise, any such JSCalendar data is invalid.
The intended usage of registry items may change between versions, but
the DE must carefully consider the impact on existing implementations
and standards before doing so.
The registration procedure is not a formal standards process but
rather an administrative procedure intended to allow community
comments and to check whether it is coherent without excessive time
delay. It is designed to encourage vendors to document and register
new items they add for use cases not covered by the original
specification, leading to increased interoperability.
7.2.1. Preliminary Community Review
Notice of a potential new registration MUST be sent to the Calext WG
mailing list <calsify@ietf.org> for review. This mailing list is
appropriate for soliciting community feedback on a proposed registry
assignment.
The intent of the public posting to this list is to solicit comments
and feedback on the choice of the item name or value, the unambiguity
of its description, and a review of any interoperability or security
considerations. The submitter may submit a revised registration
proposal or abandon the registration completely at any time.
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7.2.2. Submit Request to IANA
Registration requests can be sent to IANA <iana@iana.org>.
7.2.3. Designated Expert Review
The primary concern of the DE is preventing name collisions and
encouraging the submitter to document security and privacy
considerations.
A new type name, property name, or enumerated value MUST NOT differ
only in case from an already-registered name or value.
For a common-use registration, the DE is expected to confirm that
suitable documentation is available to ensure interoperability. The
DE should also verify that the new assignment does not conflict with
work that is active or already published within the IETF.
The DE will either approve or deny the registration request and
publish a notice of the decision to the Calext WG mailing list or its
successor, as well as inform IANA. A denial notice must be justified
by an explanation, and in the cases where it is possible, concrete
suggestions on how the request can be modified to become acceptable
should be provided.
7.2.4. Change Procedures
Once a JSCalendar registry group item has been published by IANA, the
Change Controller may request a change to its definition. The same
procedure that would be appropriate for the original registration
request is used to process a change request.
JSCalendar registrations do not get deleted; instead, items that are
no longer believed appropriate for use are declared obsolete by a
change to their "Intended Usage" field; such items will be clearly
marked in the IANA registry.
Significant changes to a JSCalendar registry item's definition should
be requested only when there are serious omissions or errors in the
published specification, as such changes may cause interoperability
issues. When review is required, a change request may be denied if
it renders entities that were valid under the previous definition
invalid under the new definition.
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7.3. "JSCalendar Version" Registry
IANA will add the "JSCalendar Version" registry to the "JSCalendar"
registry group. The purpose of this new registry is to define the
allowed value range of JSCalendar major and minor version numbers.
The registry entries sort numerically in ascending order by the
"Major Version" column, entries with equal "Major Version" sort
numerically in ascending order by the "Minor Version" column.
The registry process is defined in Section 7.2.
7.3.1. "JSCalendar Version" Registry Template
Major Version: The numeric value of a JSCalendar major version
number. It MUST be a positive integer.
Highest Minor Version: The maximum numeric value of a JSCalendar
minor version for the given major version. It MUST be zero or a
positive integer. All numbers less than or equal to this value
are valid minor version values for the given major version.
7.3.2. Initial Contents of the JSCalendar Version Registry
The following table lists the initial valid major and minor version
number ranges.
+===============+===============+=================================+
| Major Version | Highest Minor | Reference |
| | Version | |
+===============+===============+=================================+
| 1 | 0 | [RFC8984] |
+---------------+---------------+---------------------------------+
| 2 | 0 | draft-ietf-calext-jscalendarbis |
+---------------+---------------+---------------------------------+
Table 1: JSCalendar Version Registry
7.4. "JSCalendar Properties" Registry
IANA has created the "JSCalendar Properties" registry to allow
interoperability of extensions to JSCalendar objects. IANA will set
the Reference of the registry to this document, rather than obsoleted
[RFC8984].
7.4.1. "JSCalendar Properties" Registry Template
Property Name: This is the name of the property. The property name
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MUST NOT already be registered for any of the object types listed
in the "Property Context" field of this registration. Other
object types MAY already have registered a different property with
the same name; however, the same name SHOULD only be used when the
semantics are analogous.
Property Type: This is the type of this property, using type
signatures, as specified in Section 1.4.2. The property type MUST
be registered in the "JSCalendar Types" registry.
Property Context: This is a comma-separated list of JSCalendar
object types this property is allowed on.
Reference or Description: This is a brief description or RFC number
and section reference where the property is specified (omitted for
"reserved" property names).
Intended Usage: This may be "common", "reserved", or "obsolete".
Since Version: The JSCalendar version on which the property
definition is based. The version MUST be one of the allowed
values of the "version" property in the "JSCalendar Version"
registry (see Table 1).
Until Version: The JSCalendar version after which the property was
obsoleted; therefore, it MUST NOT be used in later versions. The
Until Version value either MUST NOT be set or MUST be one of the
allowed values of the "version" property in the "JSCalendar
Version" registry (see Table 1).
Change Controller: This is who may request a change to this entry's
definition ("IETF" for RFCs from the IETF stream).
7.4.2. Changes to the "JSCalendar Properties" Registry
7.4.2.1. Obsoleted Properties
IANA will change the Intended Usage from "common" to "obsolete" for
the following entries in the JSCalendar Properties Registry. For
each entry, the Property Name and its changed fields are listed.
Property Name aliases
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name cid
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Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name comments
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name daylight
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name excludedRecurrenceRules
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name language
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name locationId
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name names
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name offsetFrom
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name offsetTo
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Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name progressUpdated
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name recurrenceRules
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name standard
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name timeZones
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name tzId
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name url
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Property Name validUntil
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
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The following change only applies for the property entry where the
Property Name is "start" and the Property Context is "TimeZoneRule":
Property Name start
Property Context TimeZoneRule
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
7.4.2.2. Reserved Properties
IANA will change the Intended Usage from "common" to "reserved" for
the following entries in the JSCalendar Properties Registry. For
each entry, the Property Name and its changed fields are listed.
Property Name excluded
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name invitedBy
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name localizations
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name participationComment
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name replyTo
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name requestStatus
Reference/Description Appendix A.2.2
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Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name scheduleAgent
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name scheduleForceSend
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name scheduleSequence
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name scheduleStatus
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name scheduleUpdated
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name sendTo
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
Property Name useDefaultAlerts
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
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7.4.2.3. Updated Properties
IANA will update the following entries in the JSCalendar Properties
Registry. For each entry, the Property Name and its changed fields
are listed. Unchanged fields are omitted. Referenced section
numbers refer to this document, unless otherwise noted.
Property Name @type
Property Context Event, Task, Group, AbsoluteTrigger, Alert, Link,
Location, NDay, OffsetTrigger, Participant, RecurrenceRule,
Relation, VirtualLocation
Reference/Description Section 1.4.4
Since Version 1.0
Property Name acknowledged
Reference/Description Section 3.5.1
Since Version 1.0
Property Name action
Reference/Description Section 3.5.1
Since Version 1.0
Property Name alerts
Reference/Description Section 3.5.1
Since Version 1.0
Property Name byDay
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byHour
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byMinute
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byMonth
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byMonthDay
Reference/Description Section 3.3.3
Since Version 1.0
Property Name bySecond
Reference/Description Section 3.3.3
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Since Version 1.0
Property Name bySetPosition
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byWeekNo
Reference/Description Section 3.3.3
Since Version 1.0
Property Name byYearDay
Reference/Description Section 3.3.3
Since Version 1.0
Property Name calendarAddress
Reference/Description Section 3.4.6
Since Version 1.0
Property Name categories
Reference/Description Section 3.2.11
Since Version 1.0
Property Name color
Reference/Description Section 3.2.12
Since Version 1.0
Property Name contentType
Reference/Description Section 1.5.11
Since Version 1.0
Property Name coordinates
Reference/Description Section 3.2.5
Since Version 1.0
Property Name count
Reference/Description Section 3.3.3
Since Version 1.0
Property Name created
Reference/Description Section 3.1.5
Since Version 1.0
Property Name day
Reference/Description Section 3.3.3
Since Version 1.0
Property Name delegatedFrom
Reference/Description Section 3.4.6
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Since Version 1.0
Property Name delegatedTo
Reference/Description Section 3.4.6
Since Version 1.0
Property Name description
Property Context Event, Task, Participant
Reference/Description Section 3.2.2, Section 3.4.6
Since Version 1.0
Property Name descriptionContentType
Property Context Event, Task, Participant
Reference/Description Section 3.2.2, Section 3.4.6
Since Version 1.0
Property Name display
Reference/Description Section 1.5.11
Since Version 1.0
Property Name due
Reference/Description Section 4.2.1
Since Version 1.0
Property Name duration
Reference/Description Section 4.1.2
Since Version 1.0
Property Name email
Reference/Description Section 3.4.6
Since Version 1.0
Property Name entries
Reference/Description Section 4.3.1
Since Version 1.0
Property Name estimatedDuration
Reference/Description Section 4.2.3
Since Version 1.0
Property Name expectReply
Reference/Description Section 3.4.6
Since Version 1.0
Property Name features
Reference/Description Section 3.2.7
Since Version 1.0
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Property Name firstDayOfWeek
Reference/Description Section 3.3.3
Since Version 1.0
Property Name freeBusyStatus
Reference/Description Section 3.4.2
Since Version 1.0
Property Name frequency
Reference/Description Section 3.3.3
Since Version 1.0
Property Name href
Reference/Description Section 1.5.11
Since Version 1.0
Property Name interval
Reference/Description Section 3.3.3
Since Version 1.0
Property Name keywords
Reference/Description Section 3.2.10
Since Version 1.0
Property Name kind
Reference/Description Section 3.4.6
Since Version 1.0
Property Name links
Reference/Description Section 3.2.8, Section 3.2.5, Section 3.4.6
Since Version 1.0
Property Name locale
Reference/Description Section 3.2.9
Since Version 1.0
Property Name locationTypes
Reference/Description Section 3.2.5
Since Version 1.0
Property Name locations
Reference/Description Section 3.2.5
Since Version 1.0
Property Name memberOf
Reference/Description Section 3.4.6
Since Version 1.0
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Property Name method
Reference/Description Section 3.1.8
Since Version 1.0
Property Name name
Reference/Description Section 3.2.5, Section 3.2.7, Section 3.4.6
Since Version 1.0
Property Name nthOfPeriod
Reference/Description Section 3.3.3
Since Version 1.0
Property Name offset
Reference/Description Section 3.5.1
Since Version 1.0
Property Name participants
Reference/Description Section 3.4.6
Since Version 1.0
Property Name participationStatus
Reference/Description Section 3.4.6
Since Version 1.0
Property Name percentComplete
Reference/Description Section 4.2.4, Section 3.4.6
Since Version 1.0
Property Name priority
Reference/Description Section 3.4.1
Since Version 1.0
Property Name privacy
Reference/Description Section 3.4.3
Since Version 1.0
Property Name prodId
Reference/Description Section 3.1.4
Since Version 1.0
Property Name progress
Reference/Description Section 4.2.5, Section 3.4.6
Since Version 1.0
Property Name recurrenceId
Reference/Description Section 3.3.1
Since Version 1.0
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Property Name recurrenceIdTimeZone
Property Type TimeZoneId
Reference/Description Section 3.3.2
Since Version 1.0
Property Name recurrenceOverrides
Property Content Event, Task
Reference/Description Section 3.3.4
Since Version 1.0
Property Name rel
Reference/Description Section 1.5.11
Since Version 1.0
Property Name relatedTo
Reference/Description Section 3.1.3, Section 3.5.1
Since Version 1.0
Property Name relation
Reference/Description Section 1.5.10
Since Version 1.0
Property Name relativeTo
Property Context OffsetTrigger
Reference/Description Section 3.5.1
Since Version 1.0
Property Name roles
Reference/Description Section 3.4.6
Since Version 1.0
Property Name rscale
Reference/Description Section 3.3.3
Since Version 1.0
Property Name sentBy
Property Context Event, Task, Participant
Reference/Description Section 3.4.6, Section 3.4.5
Since Version 1.0
Property Name sequence
Reference/Description Section 3.1.7
Since Version 1.0
Property Name showWithoutTime
Reference/Description Section 3.2.4
Since Version 1.0
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Property Name size
Reference/Description Section 1.5.11
Since Version 1.0
Property Name skip
Reference/Description Section 3.3.3
Since Version 1.0
Property Name source
Reference/Description Section 4.3.2
Since Version 1.0
Property Name start
Property Context Event,Task
Reference/Description Section 4.1.1, Section 4.2.2
Since Version 1.0
Property Name status
Reference/Description Section 4.1.4
Since Version 1.0
Property Name timeZone
Property Type TimeZoneId
Property Context Event, Task
Reference/Description Section 3.6.1
Since Version 1.0
Property Name title
Reference/Description Section 3.2.1
Since Version 1.0
Property Name trigger
Reference/Description Section 3.5.1
Since Version 1.0
Property Name uid
Reference/Description Section 3.1.1
Since Version 1.0
Property Name until
Reference/Description Section 3.3.3
Since Version 1.0
Property Name updated
Reference/Description Section 3.1.6
Since Version 1.0
Property Name uri
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Reference/Description Section 3.2.7
Since Version 1.0
Property Name virtualLocations
Reference/Description Section 3.2.7
Since Version 1.0
Property Name when
Reference/Description Section 3.5.1
Since Version 1.0
7.4.2.4. Added Properties
IANA will add the following entries in the JSCalendar Properties
Registry. Referenced section numbers refer to this document, unless
otherwise noted.
Property Name calendarAddress
Property Type String
Property Context Participant
Reference/Description Section 3.4.6
Intended Usage common
Since Version 2.0
Is Per-User No
Property Name description
Property Type not applicable
Property Context Location, VirtualLocation
Reference/Description Appendix A.2.2
Intended Usage reserved
Since Version 2.0
Is Per-User No
Property Name endTimeZone
Property Type String
Property Context Event
Reference/Description Section 4.1.3
Intended Usage common
Since Version 2.0
Is Per-User No
Property Name extra
Property Type not applicable
Property Context not applicable
Reference/Description Section 1.7.3.1
Intended Usage reserved
Since Version 2.0
Is Per-User No
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Property Name mainLocationId
Property Type String
Property Context Event, Task
Reference/Description Section 3.2.6
Intended Usage common
Since Version 2.0
Is Per-User No
Property Name organizerCalendarAddress
Property Type String
Property Context Event, Task
Reference/Description Section 3.4.4
Intended Usage common
Since Version 2.0
Is Per-User No
Property Name recurrenceRule
Property Type RecurrenceRule
Property Context Event, Task
Reference/Description Section 3.3.3
Intended Usage common
Since Version 2.0
Is Per-User No
Property Name relativeTo
Property Context Location
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 2.0
Is Per-User No
Property Name timeZone
Property Context Location
Reference/Description Appendix A.2.1
Intended Usage obsolete
Since Version 2.0
Is Per-User No
Property Name version
Property Type String
Property Context Group, Event, Task
Reference/Description Section 3.1.2
Intended Usage common
Since Version 2.0
Is Per-User No
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7.5. "JSCalendar Types" Registry
IANA has created the "JSCalendar Types" registry to avoid name
collisions and provide a complete reference for all data types used
for JSCalendar property values. IANA will set the Reference of the
registry to this document, rather than obsoleted [RFC8984].
The registry policy is defined in Section 7.2.
7.5.1. "JSCalendar Types" Registry Template
Type Name: This is the name of the type.
Reference or Description: This is a brief description or RFC number
and section reference where the Type is specified (may be omitted
for "reserved" type names).
Intended Usage: This may be "common", "reserved", or "obsolete".
Since Version: The JSCalendar version on which the type definition
is based. The version MUST be one of the allowed values of the
version type in the "JSCalendar Version" registry (see Table 1).
Until Version: The JSCalendar version after which the type was
obsoleted; therefore, it MUST NOT be used in later versions. The
Until Version value either MUST NOT be set or MUST be one of the
allowed values of the version type in the "JSCalendar Version"
registry (see Table 1).
Change Controller: This is who may request a change to this entry's
definition ("IETF" for RFCs from the IETF stream)
7.5.2. Changes to the "JSCalendar Types" Registry
7.5.2.1. Obsoleted Types
IANA will change the Intended Usage from "common" to "obsolete" for
the following entries in the JSCalendar Types Registry. For each
entry, the Type Name and its changed fields are listed.
Type Name TimeZone
Reference/Description Appendix A.3.1
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
Type Name TimeZoneRule
Reference/Description Appendix A.3.1
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Intended Usage obsolete
Since Version 1.0
Until Version 1.0
7.5.2.2. Updated Types
IANA will update the following entries in the JSCalendar Types
Registry. For each entry, the Type Name and its changed fields are
listed. Unchanged fields are omitted. Referenced section numbers
refer to this document, unless otherwise noted.
Type Name Alert
Reference/Description Section 3.5.1
Since Version 1.0
Type Name Boolean
Reference/Description Section 1.4.2
Since Version 1.0
Type Name Duration
Reference/Description Section 1.5.6
Since Version 1.0
Type Name Id
Reference/Description Section 1.5.1
Since Version 1.0
Type Name Int
Reference/Description Section 1.5.2
Since Version 1.0
Type Name LocalDateTime
Reference/Description Section 1.5.5
Since Version 1.0
Type Name Link
Reference/Description Section 1.5.11
Since Version 1.0
Type Name Location
Reference/Description Section 3.2.5
Since Version 1.0
Type Name NDay
Reference/Description Section 3.3.3
Since Version 1.0
Type Name Number
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Reference/Description Section 1.4.2
Since Version 1.0
Type Name Participant
Reference/Description Section 3.4.6
Since Version 1.0
Type Name PatchObject
Reference/Description Section 1.5.9
Since Version 1.0
Type Name RecurrenceRule
Reference/Description Section 3.3.3
Since Version 1.0
Type Name Relation
Reference/Description Section 1.5.10
Since Version 1.0
Type Name SignedDuration
Reference/Description Section 1.5.7
Since Version 1.0
Type Name String
Reference/Description Section 1.4.2
Since Version 1.0
Type Name TimeZoneId
Reference/Description Section 1.5.8
Since Version 1.0
Type Name UnsignedInt
Reference/Description Section 1.5.3
Since Version 1.0
Type Name UTCDateTime
Reference/Description Section 1.5.4
Since Version 1.0
7.5.2.3. Added Types
IANA will add the following entries in the JSCalendar Types Registry.
Referenced section numbers refer to this document, unless otherwise
noted.
Type Name Event
Reference/Description Section 2.1
Intended Usage common
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Since Version 1.0
Change Controller IETF
Type Name Group
Reference/Description Section 2.3
Intended Usage common
Since Version 1.0
Change Controller IETF
Type Name Task
Reference/Description Section 2.2
Intended Usage common
Since Version 1.0
Change Controller IETF
Type Name OffsetTrigger
Reference/Description Section 3.5.1
Intended Usage common
Since Version 1.0
Change Controller IETF
Type Name AbsoluteTrigger
Reference/Description Section 3.5.1
Intended Usage common
Since Version 1.0
Change Controller IETF
Type Name UnknownTrigger
Reference/Description Section 3.5.1
Intended Usage common
Since Version 1.0
Change Controller IETF
7.6. "JSCalendar Enum Values" Registry
IANA has created the "JSCalendar Enum Values" registry to allow
interoperable extension of semantics for properties with enumerable
values. Each such property has a subregistry of allowed values.
IANA will set the Reference of the registry to this document, rather
than obsoleted [RFC8984].
The registry policy is defined in Section 7.2.
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7.6.1. "JSCalendar Enum Values" Registry Property Template
This template is for adding a subregistry for a new enumerable
property to the "JSCalendar Enum" registry. To add or amend
enumerated values for a new or existing subregistry use the template
in Section 7.6.2.
Property Name: These are the name(s) of the property or properties
where these values may be used. This MUST be registered in the
"JSCalendar Properties" registry.
Context: This is the list of allowed object types where the property
or properties may appear, as registered in the "JSCalendar
Properties" registry. This disambiguates where there may be two
distinct properties with the same name in different contexts.
Change Controller: ("IETF" for properties defined in RFCs from the
IETF stream).
Initial Contents: This is the initial list of defined values for
this enum, using the template defined in Section 7.6.2. A
subregistry will be created with these values for this property
name/context tuple.
7.6.2. "JSCalendar Enum Values" Registry Value Template
This template is for adding a new enum value to a subregistry in the
JSCalendar Enum registry.
Enum Value: This is the verbatim value of the enum.
Reference or Description: This is a brief description or RFC number
and section reference for the semantics of this value.
Intended Usage: This may be "common", "reserved", or "obsolete".
Since Version: The JSCalendar version on which the enum value
definition is based. The version MUST be one of the allowed
values of the version type in the "JSCalendar Version" registry
(see Table 1).
Until Version: The JSCalendar version after which the enum value was
obsoleted; therefore, it MUST NOT be used in later versions. The
Until Version value either MUST NOT be set or MUST be one of the
allowed values of the version type in the "JSCalendar Version"
registry (see Table 1).
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7.6.3. Changes to the "JSCalendar Enum Values" Registry
IANA will update the following entries. For each entry, the Property
Name and its changed fields are listed. Unchanged fields are
omitted.
Property Name progress
Context Task
Reference draft-ietf-calext-jscalendarbis
Property Name relativeTo
Context OffsetTrigger
Reference draft-ietf-calext-jscalendarbis
For every other existing entry, IANA will replace the contents of the
"Reference" column with a reference to this document.
7.6.4. Additions to the "JSCalendar Enum Values" Registry
IANA will add the following entry to the "JSCalendar Enum Values"
registry entry:
Property Name progress
Context Participant
Reference draft-ietf-calext-jscalendarbis
Change Controller IETF
IANA will add the following enumerated values in the newly created
subregistry:
Enum Value in-process
Reference/Description Section 3.4.6
Intended Usage common
Since Version 2.0
Until Version
Change Controller IETF
Enum Value completed
Reference/Description Section 3.4.6
Intended Usage common
Since Version 2.0
Until Version
Change Controller IETF
Enum Value failed
Reference/Description Section 3.4.6
Intended Usage common
Since Version 2.0
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Until Version
Change Controller IETF
7.6.5. Changes to the "JSCalendar Enum Values for action (Context:
Alert)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.5.1
Intended Usage common
Since Version 1.0
Until Version
7.6.6. Changes to the "JSCalendar Enum Values for display (Context:
Link)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 1.5.11
Intended Usage common
Since Version 1.0
Until Version
7.6.7. Changes to the "JSCalendar Enum Values for features (Context:
VirtualLocation)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.2.7
Intended Usage common
Since Version 1.0
Until Version
7.6.8. Changes to the "JSCalendar Enum Values for freeBusyStatus
(Context: Event, Task)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.4.2
Intended Usage common
Since Version 1.0
Until Version
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7.6.9. Changes to the "JSCalendar Enum Values for kind (Context:
Participant)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.4.6
Intended Usage common
Since Version 1.0
Until Version
7.6.10. Changes to the "JSCalendar Enum Values for participationStatus
(Context: Participant)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.4.6
Intended Usage common
Since Version 1.0
Until Version
7.6.11. Changes to the "JSCalendar Enum Values for privacy (Context:
Event, Task)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.4.3
Intended Usage common
Since Version 1.0
Until Version
7.6.12. Changes to the "JSCalendar Enum Values for progress (Context:
Task, Participant)" Registry
IANA will rename the sub-registry to "JSCalendar Enum Values for
progress (Context: Task)".
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 4.2.5
Intended Usage common
Since Version 1.0
Until Version
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7.6.13. Changes to the "JSCalendar Enum Values for relation (Context:
Relation)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 1.5.10
Intended Usage common
Since Version 1.0
Until Version
IANA will add the following entry:
Enum Value snooze
Reference/Description Section 3.5.1
Intended Usage common
Since Version 2.0
Until Version
Change Controller IETF
7.6.14. Changes to the "JSCalendar Enum Values for relativeTo (Context:
OffsetTrigger, Location)" Registry
IANA will rename the sub-registry to "JSCalendar Enum Values for
"relativeTo" (Context: OffsetTrigger)".
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 3.5.1
Intended Usage common
Since Version 1.0
Until Version
7.6.15. Changes to the "JSCalendar Enum Values for roles (Context:
Participant)" Registry
For the entry with enum value "attendee", IANA will set the following
fields:
Reference Appendix A.2.3
Intended Usage obsolete
Since Version 1.0
Until Version 1.0
For every other existing entry, IANA will set the following fields:
Reference Section 3.4.6
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Intended Usage common
Since Version 1.0
Until Version
7.6.16. Changes to the "JSCalendar Enum Values for scheduleAgent
(Context: Participant)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Appendix A.2.2
Intended Usage reserved
Since Version 1.0
Until Version 1.0
7.6.17. Changes to the "JSCalendar Enum Values for status (Context:
Event)" Registry
For every existing entry, IANA will set the following fields.
Unchanged fields are omitted.
Reference Section 4.1.4
Intended Usage common
Since Version 1.0
Until Version
8. References
8.1. Normative References
[CLDR] "Unicode Common Locale Data Repository",
<http://cldr.unicode.org/>.
[CSS3] Çelik, T., Lilley, C., and L. Baron, "CSS Color Module
Level 3", W3C Recommendation, January 2022,
<https://www.w3.org/TR/css-color-3/>.
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
<https://www.rfc-editor.org/info/rfc1034>.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
November 1987, <https://www.rfc-editor.org/info/rfc1035>.
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC2397] Masinter, L., "The "data" URL scheme", RFC 2397,
DOI 10.17487/RFC2397, August 1998,
<https://www.rfc-editor.org/info/rfc2397>.
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
<https://www.rfc-editor.org/info/rfc3339>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>.
[RFC4589] Schulzrinne, H. and H. Tschofenig, "Location Types
Registry", RFC 4589, DOI 10.17487/RFC4589, July 2006,
<https://www.rfc-editor.org/info/rfc4589>.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
<https://www.rfc-editor.org/info/rfc4648>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
[RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
DOI 10.17487/RFC5322, October 2008,
<https://www.rfc-editor.org/info/rfc5322>.
[RFC5545] Desruisseaux, B., Ed., "Internet Calendaring and
Scheduling Core Object Specification (iCalendar)",
RFC 5545, DOI 10.17487/RFC5545, September 2009,
<https://www.rfc-editor.org/info/rfc5545>.
[RFC5546] Daboo, C., Ed., "iCalendar Transport-Independent
Interoperability Protocol (iTIP)", RFC 5546,
DOI 10.17487/RFC5546, December 2009,
<https://www.rfc-editor.org/info/rfc5546>.
[RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
September 2009, <https://www.rfc-editor.org/info/rfc5646>.
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[RFC5870] Mayrhofer, A. and C. Spanring, "A Uniform Resource
Identifier for Geographic Locations ('geo' URI)",
RFC 5870, DOI 10.17487/RFC5870, June 2010,
<https://www.rfc-editor.org/info/rfc5870>.
[RFC6638] Daboo, C. and B. Desruisseaux, "Scheduling Extensions to
CalDAV", RFC 6638, DOI 10.17487/RFC6638, June 2012,
<https://www.rfc-editor.org/info/rfc6638>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>.
[RFC6901] Bryan, P., Ed., Zyp, K., and M. Nottingham, Ed.,
"JavaScript Object Notation (JSON) Pointer", RFC 6901,
DOI 10.17487/RFC6901, April 2013,
<https://www.rfc-editor.org/info/rfc6901>.
[RFC7493] Bray, T., Ed., "The I-JSON Message Format", RFC 7493,
DOI 10.17487/RFC7493, March 2015,
<https://www.rfc-editor.org/info/rfc7493>.
[RFC7529] Daboo, C. and G. Yakushev, "Non-Gregorian Recurrence Rules
in the Internet Calendaring and Scheduling Core Object
Specification (iCalendar)", RFC 7529,
DOI 10.17487/RFC7529, May 2015,
<https://www.rfc-editor.org/info/rfc7529>.
[RFC7809] Daboo, C., "Calendaring Extensions to WebDAV (CalDAV):
Time Zones by Reference", RFC 7809, DOI 10.17487/RFC7809,
March 2016, <https://www.rfc-editor.org/info/rfc7809>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
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[RFC8288] Nottingham, M., "Web Linking", RFC 8288,
DOI 10.17487/RFC8288, October 2017,
<https://www.rfc-editor.org/info/rfc8288>.
[RFC8984] Jenkins, N. and R. Stepanek, "JSCalendar: A JSON
Representation of Calendar Data", RFC 8984,
DOI 10.17487/RFC8984, July 2021,
<https://www.rfc-editor.org/info/rfc8984>.
[RFC9073] Douglass, M., "Event Publishing Extensions to iCalendar",
RFC 9073, DOI 10.17487/RFC9073, August 2021,
<https://www.rfc-editor.org/info/rfc9073>.
[RFC9074] Daboo, C. and K. Murchison, Ed., ""VALARM" Extensions for
iCalendar", RFC 9074, DOI 10.17487/RFC9074, August 2021,
<https://www.rfc-editor.org/info/rfc9074>.
[RFC9253] Douglass, M., "Support for iCalendar Relationships",
RFC 9253, DOI 10.17487/RFC9253, August 2022,
<https://www.rfc-editor.org/info/rfc9253>.
[RFC9562] Davis, K., Peabody, B., and P. Leach, "Universally Unique
IDentifiers (UUIDs)", RFC 9562, DOI 10.17487/RFC9562, May
2024, <https://www.rfc-editor.org/info/rfc9562>.
[TZDB] IANA, "Time Zone Database",
<https://www.iana.org/time-zones>.
8.2. Informative References
[I-D.ietf-calext-ical-tasks]
Apthorp, A. and M. Douglass, "Task Extensions to
iCalendar", Work in Progress, Internet-Draft, draft-ietf-
calext-ical-tasks-17, 9 December 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-calext-
ical-tasks-17>.
[I-D.ietf-calext-icalendar-jscalendar-extensions]
Stepanek, R., "iCalendar Format Extensions for
JSCalendar", Work in Progress, Internet-Draft, draft-ietf-
calext-icalendar-jscalendar-extensions-05, 19 January
2026, <https://datatracker.ietf.org/doc/html/draft-ietf-
calext-icalendar-jscalendar-extensions-05>.
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Internet-Draft JSCalendar July 2026
[I-D.ietf-calext-jscalendar-icalendar]
Stepanek, R., "JSCalendar: Converting from and to
iCalendar", Work in Progress, Internet-Draft, draft-ietf-
calext-jscalendar-icalendar-23, 1 June 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-calext-
jscalendar-icalendar-23>.
[I-D.ietf-jmap-calendars]
Jenkins, N. and M. Douglass, "JSON Meta Application
Protocol (JMAP) for Calendars", Work in Progress,
Internet-Draft, draft-ietf-jmap-calendars-26, 4 November
2025, <https://datatracker.ietf.org/doc/html/draft-ietf-
jmap-calendars-26>.
[ISO.9070.1991]
ISO/IEC, "Information technology -- SGML support
facilities -- Registration procedures for public text
owner identifiers", Edition 2, ISO/IEC 9070:1991, April
1991, <https://www.iso.org/standard/16645.html>.
[LOCATIONTYPES]
IANA, "Location Types Registry",
<https://www.iana.org/assignments/location-type-registry>.
[MEDIATYPES]
IANA, "Media Types",
<https://www.iana.org/assignments/media-types>.
[RFC3987] Duerst, M. and M. Suignard, "Internationalized Resource
Identifiers (IRIs)", RFC 3987, DOI 10.17487/RFC3987,
January 2005, <https://www.rfc-editor.org/info/rfc3987>.
[RFC6376] Crocker, D., Ed., Hansen, T., Ed., and M. Kucherawy, Ed.,
"DomainKeys Identified Mail (DKIM) Signatures", STD 76,
RFC 6376, DOI 10.17487/RFC6376, September 2011,
<https://www.rfc-editor.org/info/rfc6376>.
[RFC7265] Kewisch, P., Daboo, C., and M. Douglass, "jCal: The JSON
Format for iCalendar", RFC 7265, DOI 10.17487/RFC7265, May
2014, <https://www.rfc-editor.org/info/rfc7265>.
[RFC7986] Daboo, C., "New Properties for iCalendar", RFC 7986,
DOI 10.17487/RFC7986, October 2016,
<https://www.rfc-editor.org/info/rfc7986>.
[RFC8499] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
Terminology", RFC 8499, DOI 10.17487/RFC8499, January
2019, <https://www.rfc-editor.org/info/rfc8499>.
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[RFC8607] Daboo, C., Quillaud, A., and K. Murchison, Ed.,
"Calendaring Extensions to WebDAV (CalDAV): Managed
Attachments", RFC 8607, DOI 10.17487/RFC8607, June 2019,
<https://www.rfc-editor.org/info/rfc8607>.
[RFC9553] Stepanek, R. and M. Loffredo, "JSContact: A JSON
Representation of Contact Data", RFC 9553,
DOI 10.17487/RFC9553, May 2024,
<https://www.rfc-editor.org/info/rfc9553>.
[UBiDi] The Unicode Consortium, "Unicode Standard Annex #9:
Unicode Bidirectional Algorithm", Revision 48,
Unicode 15.1.0, August 2023,
<https://www.unicode.org/reports/tr9/>.
[WHATWG-URL]
WHATWG, "URL Living Standard", January 2024,
<https://url.spec.whatwg.org>.
Appendix A. Differences from RFC 8984
This section documents all significant differences from RFC 8984.
Insignificant differences, such as formatting, grammar or typos are
not documented.
A.1. Applied Errata
All verified errata of RFC 8984 was applied to this document:
* Errata 6872 (https://www.rfc-editor.org/errata/eid6872)
* Errata 6873 (https://www.rfc-editor.org/errata/eid6873)
* Errata 8028 (https://www.rfc-editor.org/errata/eid8028)
A.2. Changed Property Definitions
This section summarizes the differences from the JSCalendar property
definitions of [RFC8984].
A.2.1. Obsoleted Properties
The following properties became obsolete:
*excludedRecurrenceRules*:
This is incompatible with iCalendar, which deprecated the EXRULE
property in [RFC5545].
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See Section 4.3.4 of [RFC8984].
*recurrenceRules*:
This is incompatible with the following definitions of the
iCalendar RRULE property [RFC5545] (Section 3.8.5.3):
* The RRULE property SHOULD NOT be specified more than once.
* The recurrence set generated with multiple RRULE properties is
undefined.
The newly defined single-valued "recurrenceRule" property
(Section 3.3.3) replaces it.
See Section 4.3.3 of [RFC8984].
*timeZones*:
This property was obsoleted for the following reasons:
* Custom time zones in calendaring data increase implementation
complexity, introduce inefficiencies and are error-prone, as
described for CalDAV and iCalendar in [RFC7809].
* In practice, the only non-IANA time zone identifiers are
Microsoft time zone names. These can be converted to IANA time
zones, e.g. using the International Components for Unicode
(https://icu.unicode.org/) software library.
* The property contradicts the stated goal of JSCalendar to avoid
ambiguities and pitfalls of iCalendar, defined in Section 1.1
of [RFC8984].
See Section 4.7.2 of [RFC8984].
*Link.cid*:
This property was obsoleted for the following reasons:
* It only is relevant for rich-text descriptions, but the related
iCalendar STYLED-DESCRIPTION property [RFC9073] (Section 6.5)
does not support referring to attached media.
* It only is applicable for Link objects having a "data:" URI as
"href" property value. But even the definition of the Link
object recommends not to use "data:" URIs as values in the
"href" property.
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* A Link with "data:" URI converts to an iCalendar BINARY value
[RFC5545] (Section 3.3.1). But these are marginally supported
by CalDAV clients, which tend to prefer using WebDAV managed
attachments [RFC8607].
See Section 1.4.11 of [RFC8984].
*Location.{relativeTo|timeZone}*:
These got replaced with the newly defined Event.endTimeZone
property (Section 4.1.3):
* They were meant to be equivalent to the iCalendar DTEND
property [RFC5545] (Section 3.8.2.2). But the semantics were
undefined if multiple Location objects had "relativeTo=end" and
the "timeZone" property set.
* Their semantics were undefined for Task objects.
* They were incompatible with the iCalendar VLOCATION component
[RFC9073] (Section 7.2), which neither defines how to set a
time zone identifier or how the VLOCATION relates to start and
end.
See Section 4.2.5 of [RFC8984].
*Participant.locationId*:
This is incompatible with the iCalendar PARTICIPANT component
[RFC9073] (Section 7.1):
* The PARTICIPANT component may contain multiple VLOCATION
components and LOCATION properties.
* The PARTICIPANT component does not support referring to other
VLOCATION components or LOCATION properties
The description of the Event object type in Section 2.1 reflects
this:
* It stated: "Multiple participants may partake in the event at
multiple locations."
* It now states: "Multiple participants may partake in the
event."
See Section 4.4.6 of [RFC8984].
*Participant.language*:
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No equivalent element exists in iCalendar and its current single-
valued definition is likely to conflict with any related future
extension of the PARTICIPANT component [RFC9073] (Section 7.1).
See Section 4.4.6 of [RFC8984].
*{Participant|Task}.progressUpdated*:
This became obsolete for the following reasons:
* It is incompatible with the newly introduced iCalendar VSTATUS
component [I-D.ietf-calext-ical-tasks] (Section 12.1), which
may occur multiple times in the PARTICIPANT and VTODO
components.
* The VSTATUS component introduces new semantics to a task's
progress and status, which better be defined by a future
JSCalendar extension for tasks.
See Section 4.4.6 of [RFC8984] and Section 5.2.6 of [RFC8984].
*{TimeZone|TimeZoneRule}.**:
All properties defined solely for the TimeZone and TimeZoneRule
object types became obsolete, because the "timeZones" property
became obsolete.
See Section 4.7.2 of [RFC8984].
A.2.2. Reserved Properties
A.2.2.1. JMAP for Calendars
The following common use properties became reserved for JMAP for
Calendars [I-D.ietf-jmap-calendars]:
*useDefaultAlerts*:
No equivalent element exists in iCalendar and no consensus for
default alarms in CalDAV and iCalendar was found at IETF as part
of [RFC9074].
See Section 4.4.1 of [RFC8984].
*Participant.scheduleSequence*:
This requires further work by IETF to update iTIP [RFC5546] with
the PARTICIPANT component and JSCalendar. This property may later
be redefined for common use.
See Section 4.4.6 of [RFC8984].
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*Participant.scheduleUpdated*:
This requires further work by IETF to update iTIP [RFC5546] with
the PARTICIPANT component and JSCalendar. This property may later
be redefined for common use.
See Section 4.4.6 of [RFC8984].
A.2.2.2. Scheduling Extensions for CalDAV and iTIP
The following common use properties became reserved for future
JSCalendar extensions of Scheduling Extensions for CalDAV [RFC6638]
and iTIP [RFC5546]:
*replyTo*:
This requires further work by IETF. For compatibility with
iCalendar, the newly introduced "organizerCalendarAddress"
property (Section 3.4.4) replaces it.
See Section 4.4.4 of [RFC8984].
*requestStatus*:
This mainly is applicable in scheduling over CalDAV.
See Section 4.4.7 of [RFC8984].
*Participant.invitedBy*:
This requires further work by IETF. Specifically, the iTIP
definitions of the REPLY method [RFC5546] (Section 3.2.3) and how
to forward invitation requests (Section 4.2.8 of [RFC5546]) must
be updated.
See Section 4.4.6 of [RFC8984].
*Participant.participationComment*:
This requires further work by IETF to update iTIP [RFC5546] with
the PARTICIPANT component or JSCalendar. This property may later
be redefined for common use.
See Section 4.4.6 of [RFC8984].
*Participant.scheduleAgent*:
This only is applicable in scheduling over CalDAV.
See Section 4.4.6 of [RFC8984].
*Participant.scheduleForceSend*:
This only is applicable in scheduling over CalDAV.
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See Section 4.4.6 of [RFC8984].
*Participant.scheduleStatus*:
This only is applicable in scheduling over CalDAV.
See Section 4.4.6 of [RFC8984].
*Participant.sendTo*:
This requires further work by IETF. For compatibility with
iCalendar, the newly introduced Participant.calendarAddress
property (Section 3.4.6) replaces it.
See Section 4.4.6 of [RFC8984].
A.2.2.3. Localization Extensions for iCalendar and JSCalendar
The following properties became reserved for future JSCalendar and
iCalendar extensions for multi-lingual calendar data:
*localizations*:
This requires further work by IETF. The "localizations" property
primarily was introduced in JSCalendar for event publishing, but
neither the Event Publishing extensions for iCalendar [RFC9073]
nor other iCalendar extensions define how to localize iCalendar
data. This property may later be redefined for common use.
See Section 4.6.1 of [RFC8984].
A.2.2.4. Reserved for Future RFCs
The following properties became reserved for some future JSCalendar
extension RFCs:
*Location.description, VirtualLocation.description*:
This requires further work by IETF. The VirtualLocation
"description" property does not convert to any parameter of the
CONFERENCE property. It would require to define a new parameter
or to introduce a new component to augment the CONFERENCE property
with a DESCRIPTION or STYLED-DESCRIPTION property. For
consistency, the Location "description" property became reserved,
too.
See Section 4.2.5 of [RFC8984] and Section 4.2.6 of [RFC8984].
A.2.2.5. Reserved for Internal Use
The following properties became reserved for internal use by
JSCalendar:
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*excluded*:
This property name already was defined for internal use only in
the "recurrenceOverrides" property, but registering it for common
use had made it appear as being a regular property. Making this a
reserved property is to help clarify its purpose. Section 3.3.4
has been updated accordingly.
See Section 4.3.4 of [RFC8984].
A.2.3. Updated Properties
The following property definitions were updated:
*@type*:
The original definition required this property be set on every
object type. The type and property notation in Section 1.4 now
matches the one in JSContact, and the "@type" property is optional
in the majority of cases.
*Alert.relatedTo*:
The original definition instructed to set the "parent" relation on
a snooze alert. It now instructs to set the newly defined
"snooze" relation, for compatibility with the VALARM "SNOOZE"
relationship type (Section 7 of [RFC9074].
The original definition did not define that the map keys represent
keys of Alert objects in the "alerts" property.
See Section 3.5.1.
*Alert.trigger*:
JSCalendar now supports default types for properties of type
"A|B". The default type of this property now is OffsetTrigger.
See Section 3.5.1.
*{Event|Task|Group}.color*:
The original definition allowed hexadecimal RGB values, which CSS3
specifies to be either in three-digit or six-digit form. The
updated definition only allows them in six-digit form to match the
proposed update of the iCalendar COLOR property. It also
explicitly defines that values are case-insensitive.
See Section 3.2.12.
*Link.display*:
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The original definition only allowed one purpose to be set, which
is incompatible with the multi-valued iCalendar DISPLAY parameter
[RFC7986] (Section 6.1). It now supports setting multiple
purposes.
Setting this property does not anymore require the "rel" property
of the Link object be set to "icon".
See Section 1.5.11.
*Link.rel*:
The original definition restricted the value of this property to
registered link types. It now also allows extension relation
types for compatibility with the LINKREL parameter [RFC9253]
(Section 6.1).
See Section 1.5.11.
*Participant.delegatedFrom*, *Participant.delegatedTo*,
*Participant.memberOf*,
The original definitions required their values to identify
Participant objects. This was incompatible with iCalendar when
the DELEGATED-TO, DELEGATED-FROM or MEMBER parameters contained a
calendar address but no ATTENDEE property with that same calendar
address. The new definition now requires the property values to
be calendar addresses.
Also, they now require the "calendarAddress" property to be set.
See Section 3.4.6.
*Participant.expectReply*, *Participant.invitedBy*,
*Participant.kind*, *Participant.participationStatus*,
*Participant.progress*, *Participant.sentBy*:
The original definitions were incompatible with iCalendar: they
did not require the (now reserved) "sendTo" property to be set,
but their equivalent iCalendar parameters require an ATTENDEE
property. They now require the "calendarAddress" property to be
set.
See Section 3.4.6.
*Participant.progress*:
The original definition was incompatible with iCalendar. It
allowed the progress value to be "cancelled", but this is not a
supported PARTSTAT parameter value of an ATTENDEE property in a
VTODO component. The new definition only supports the "progress"
property values "in-process", "completed" and "failed".
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See Section 3.4.6.
*Participant.roles*:
The original definition was incompatible with iCalendar:
* It did not cover the "REQ-PARTICIPANT" value of the ROLE
parameter [RFC5545] (Section 3.2.16). It now defines the new
"required" role.
* The "roles" property is multi-valued but the ROLE parameter is
single-valued and only allowed to be set once on an ATTENDEE.
For compatibility, a precendence of Participant roles got
defined for converting roles to iCalendar.
* It was mandatory for a Participant, but the (now reserved)
"sendTo" property was not. This was incompatible with
iCalendar, which required an ATTENDEE property to set the ROLE
parameter. It now is optional, but requires the
"calendarAddress" property to be set.
* It defined a "contact" role, but this role later got redefined
as an enumerated value of the PARTICIPANT-TYPE property
[RFC9073] (Section 6.2). It now removed this role and leaves
defining participant types to a future JSCalendar extension.
* The "attendee" role got removed. There is no equivalent ROLE
value in iCalendar and any Participant with a "calendarAddress"
by definition is an ATTENDEE in iCalendar.
* The "owner" role got redefined. It now makes clear that the
semantics of the role depend on the calendaring exchange
protocol.
See Section 3.4.6.
*Relation.relation*:
The original definition specified the empty relation to represent
an unspecified relationship. It now defines the empty relation to
default to "parent", unless overridden, for compatibility with the
RELATED-TO property [RFC5545] (Section 3.8.4.5).
See Section 1.5.10.
*{Event|Task}.recurrenceIdTimeZone*:
The property value now does not support "null" values anymore.
The property either is set to a timezone identifier, or not at
all.
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See Section 3.3.2.
*{Event|Task}.sentBy*:
The property now requires the "organizerCalendarAddress" property
to be set.
See Section 3.4.5.
*{Event|Task}.timeZone*:
The property value now does not support "null" values anymore.
The property either is set to a timezone identifier, or not at
all.
See Section 3.6.1.
*Task.{due|start}*:
The original definition defined these as optional, but this is
incompatible with iCalendar: if the Task object's "timeZone"
property is set, then it requires the DUE property [RFC5545]
(Section 3.8.2.3) or DTSTART property [RFC5545] (Section 3.8.2.4)
be set in the VTODO component. It now requires at least one of
the "due" or "start" properties be set, if the "timeZone" property
is set.
The original definition did not require the "start" property be
set if the "recurrenceRule" property is set. But this is
incompatible with the RRULE property [RFC5545] (Section 3.8.5.3),
which requires the DTSTART property be set in the VTODO component.
The "start" property now is required if the "recurrenceRule" or
"recurrenceId" properties are set.
The "showWithoutTime" property having value "true" now requires at
least one of the "due" or "start" properties be set.
See Section 4.2.
A.2.4. New Properties
The following new properties were defined:
*mainLocationId*:
This got introduced for better interoperatibility with iCalendar,
where the VEVENT and VTODO components allow at most one LOCATION
property to be present. While VLOCATION components [RFC9073]
(Section 7.2) may occur multiple times, implementations need to
know which Location to choose for the LOCATION property.
See Section 3.2.6.
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*organizerCalendarAddress*:
This replaces the reserved "replyTo" property.
See Section 3.4.4.
*recurrenceRule*:
This replaces the obsoleted "recurrenceRules" property.
See Section 3.3.3.
*version*:
This adds versioning (Section 1.9) to JSCalendar, as defined for
JSContact [RFC9553].
See Section 3.1.2.
*Event.endTimeZone*:
This replaces the obsoleted Location.relativeTo and
Location.timeZone properties.
See Section 4.1.3.
*Location.descriptionContentType*:
This is for compatibility with the iCalendar STYLED-DESCRIPTION
property [RFC9073] (Section 6.5) of the VLOCATION component.
See Section 3.2.5.
*Participant.calendarAddress*:
This replaces the reserved Participant.sendTo property.
See Section 3.4.6.
*Participant.descriptionContentType*:
This is for compatibility with the iCalendar STYLED-DESCRIPTION
property [RFC9073] (Section 6.5) of the PARTICIPANT component.
See Section 3.2.5.
*VirtualLocation.descriptionContentType*:
This is for consistency with the definition of the Location object
type. The newly defined VCONFERENCE component will be allowed to
contain the STYLED-DESCRIPTION property [RFC9073] (Section 6.5).
See Section 3.2.7.
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A.3. Changed Type Definitions
This section summarizes the differences from the JSCalendar type
definitions of [RFC8984].
A.3.1. Obsoleted Types
The following type definitions became obsolete:
*TimeZone, TimeZoneRule*:
The "timeZones" property became obsolete.
See Section 4.7.2 of [RFC8984].
A.3.2. Updated Types
The following type definitions were updated:
*Duration, LocalDateTime, UTCDateTime*:
The original definitions supported fractional seconds. This is
incompatible with the iCalendar DATE-TIME and DURATION types
defined in Section 3.3.5 of [RFC5545] and Section 3.3.6 of
[RFC5545].
Acknowledgments
The authors would like to thank the members of CalConnect for their
valuable contributions. This specification originated from the work
of the API technical committee of CalConnect: The Calendaring and
Scheduling Consortium.
Authors' Addresses
Neil Jenkins
Fastmail
Collins St. West
P.O. Box 234
Melbourne VIC 8007
Australia
Email: neilj@fastmailteam.com
URI: https://www.fastmail.com
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Robert Stepanek
Fastmail
Collins St. West
P.O. Box 234
Melbourne VIC 8007
Australia
Email: rsto@fastmailteam.com
URI: https://www.fastmail.com
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