Network Working Group G. Destiny
Internet-Draft C. Luck
Intended status: Informational Divination Inc.
Expires: September 24, 2018 March 23, 2018
An API For Calendar-Based Fortune Heuristics Services
draft-divination-cfapi-00
Abstract
This document describes a JSON HTTP API for online services that
provide calendar-based fortune heuristics.
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
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 24, 2018.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
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.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . 3
3. Fortune Heuristics Service Well-Known URI . . . . . . . . . . 3
3.1. Well-Known URI Redirection . . . . . . . . . . . . . . . 3
3.2. Well-Known URI Cache Behavior . . . . . . . . . . . . . . 3
4. New HTTP Methods: SEEK and DIVINE . . . . . . . . . . . . . . 4
5. Defined Data Types: Date-Time Formats . . . . . . . . . . . . 4
6. Fortune Heuristics Service Discovery . . . . . . . . . . . . 4
6.1. Root of Fortune Path URI ("/") . . . . . . . . . . . . . 4
7. Fortune Heuristics Service Endpoint . . . . . . . . . . . . . 5
7.1. Service Specification Request . . . . . . . . . . . . . . 6
7.2. Service Specification Object . . . . . . . . . . . . . . 8
8. Fortune Heuristics Report Request and Response . . . . . . . 9
8.1. Fortune Heuristics Report Request . . . . . . . . . . . . 9
8.2. Fortune Heuristics Report Response . . . . . . . . . . . 10
8.3. Report Interval Object . . . . . . . . . . . . . . . . . 12
8.4. Report Events Object . . . . . . . . . . . . . . . . . . 13
8.5. Report Generation Errors . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 15
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
10.1. Well-Known URI Registrations . . . . . . . . . . . . . . 15
10.1.1. "fortune" Well-Known URI Registration . . . . . . . 15
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
11.1. Normative References . . . . . . . . . . . . . . . . . . 16
11.2. Informative References . . . . . . . . . . . . . . . . . 16
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Fortune-telling, the practice of predicting information about a
person's life, is an activity practiced throughout history.
While there are myriad forms of fortune telling methodologies, this
document applies to a particular form of service that provides
fortune heuristics, commonly known as "luck", for a particular
subject based on a calendar-based input.
Since HTTP [RFC7230] status codes are insufficient to convey
information about fortune heuristics, this specification defines a
simple JSON [RFC8259] document format for this purpose. The response
can be used by HTTP APIs to deliver results to non-human clients or
to an end-user.
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2. Conventions Used in This Document
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 following definitions apply in this document:
Well-known URI
This specification makes use of the "well-known URI" feature of
HTTP servers [RFC5785] to provide a bootstrapping URI for the
client usage of fortune heuristics services.
Root of Fortune
The service discovery endpoint that provides a URI list of
available fortune heuristic endpoints available, in accordance
with Section 6.
3. Fortune Heuristics Service Well-Known URI
A well-known URI called "fortune" is registered by this specification
for fortune heuristics services (see Section 10).
Services complying with this document *SHOULD* have its well-known
URI pointing (directly or through redirection) to the Root of
Fortune.
The Root of Fortune can be used by the client for service discovery,
namely, the available calendar-based fortune heuristics services
available on the server, as specified in Section 6.
3.1. Well-Known URI Redirection
Servers *MUST* redirect HTTP requests for that resource to the actual
"context path" using one of the available mechanisms provided by HTTP
[RFC7230] (e.g., using a 301, 303, or 307 response).
Clients *MUST* handle HTTP redirects on the well-known URI.
3.2. Well-Known URI Cache Behavior
Servers *SHOULD* set an appropriate Cache-Control header value (as
according to Section 5.2 of [RFC7234]) in the redirect response to
set caching behavior as required by the type of response generated.
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4. New HTTP Methods: SEEK and DIVINE
This specification defines two new HTTP methods: "SEEK" and "DIVINE"
methods for HTTP [RFC7230].
While HTTP GET requests are treated equivalently as the "SEEK" and
"DIVINE" requests, its usage is discouraged and therefore *SHOULD
NOT* be used.
Usage of these methods are defined in the sections below.
5. Defined Data Types: Date-Time Formats
This specification defines a number of date-time formats as according
to the conventions of [RFC3339] for the unambiguous communication
between client and server.
The types defined are as follows.
DATETIME
As described in Section 5.6 of [RFC3339], with the addition that
reduced accuracy representations described in [ISO.8601-1.2018]
are supported. Reduced accuracy date and times are accepted where
a date or time component (2-digits long) is replaced by "--".
For example, the date time "2018-04---T01:02:00Z" represents the
UTC time of 1:02am, on an unknown day within April of the year
2018.
DATE
As described in "DATETIME", but the "time" component will not be
taken into account in the algorithm.
6. Fortune Heuristics Service Discovery
6.1. Root of Fortune Path URI ("/")
The Root of Fortune URI, defined as "/" in this document, is used for
service discovery on types of calendar-based fortune heuristics
available.
An empty SEEK request with the "application/json" request type *MUST*
be sent to this endpoint to retrieve the available endpoints. All
other HTTP methods *MUST NOT* be supported at this URI.
An example of such a response is as follows:
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HTTP/1.1 200 Success
Content-Type: application/json
Content-Language: en
{
"diviners" : [
"/astrology",
"/bazi",
]
}
A service discovery object *MUST* have the following members:
diviners
(JSON array) An array that contains endpoints that conform to this
specification. All endpoints listed here are relative to the Root
of Fortune path. For example, the path "/astrology" listed in the
example has an endpoint path of "[root-of-fortune]/astrology",
where "[root-of-fortune]" indicates the real path of the Root of
Fortune.
7. Fortune Heuristics Service Endpoint
An endpoint offering fortune heuristics services *MUST* adhere to
specifications in this section.
A service *MAY* implement multiple divination services based on
different divination methods, such as the digital oracle shown in
Figure 1.
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__
__===^-\
__=== -\
__===- -\
__===- -\
___===- -\
===- ---__ -\
\\\ |||^^\ \__ -\
\\\ ||| \__ -\
\\\ ||| ______\_ -\
\\\ ||| _/-******\\__ -\
\\\ || /-****_****-\ \_ -\
\\\ || |-***/ \***-\ \_ -\
\\\ || |-***\___/***-| \ -\
\\\ || \-*********-/ __--/ -\
\\\ || \-******/__-- -\
\\\ || __-- -\
\\\ || __-- -\
\\\ ||__-- -\
\\\ -\
\\\ -\
\\\ -\
\\\ -\
\\\ __ -\
\\\ //##\\ -\
\\\ \\##// -\
\\\ ^^ __--==^
\\\ __--===
\\\ __--===
\\\ __--===
\\\ __--==
\\=
Figure 1: Dimensional Eye, a digital oracle that communicates through
one button
7.1. Service Specification Request
To retrieve capabilities and parameters of an endpoint complying with
this specification, a service specification JSON object is returned.
An empty SEEK request with the "application/json" request type *MUST*
be sent to this endpoint to retrieve the service specification that
describes parameters accepted by this endpoint.
Two examples of such a response are given below.
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HTTP/1.1 200 Success
Content-Type: application/json
Content-Language: en
{
"description": "Gaze into your upcoming luck!",
"details": "https://divine.example.com/manual/astrology-api",
"parameters": {
"birthday": {
"type": "DATE",
"description": "Your birth date in UTC"
},
"targetDateBegin": {
"type": "DATE",
"description": "Start of the target date range to report on"
},
"targetDateEnd": {
"type": "DATE",
"description": "End of the target date range to report on"
},
"interval": {
"values": {
"D": "Daily",
"M": "Monthly",
"Y": "Yearly"
},
"description": "Available intervals to report on."
}
}
}
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HTTP/1.1 200 Success
Content-Type: application/json
Content-Language: en
{
"description": "Matches and mis-matches according to the "
"Yin Yang and Five Elements techniques",
"details": "https://divine.example.com/manual/bazi-api",
"parameters": {
"birthday": {
"type": "DATETIME",
"description": "Your birth date and time in UTC"
},
"targetDateBegin": {
"type": "DATETIME",
"description": "Start of the target date/time range to report on"
},
"targetDateEnd": {
"type": "DATETIME",
"description": "End of the target date/time range to report on"
},
"interval": {
"values": {
"H": "Hourly",
"D": "Daily",
"M": "Monthly",
"Y": "Yearly"
},
"description": "Available intervals to report on."
}
}
}
7.2. Service Specification Object
A service specification object *MUST* contain the following members.
description
(string) A short, human-readable summary of the fortune heuristic
service at this endpoint. This *SHOULD* be a stable reference.
details
(URI, optional) A URI reference that provides further details for
human consumption, such as API documentation that includes details
of parameters accepted or response states.
parameters
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(object, mandatory) An object that specifies what parameters are
accepted by this endpoint. Each parameter key within this object
specifies an accepted parameter name, and its value is a parameter
specification object, which is described below.
A parameter specification object *SHOULD* contain the following
members:
type
(string, optional) The value type accepted by this parameter.
Value types are described in this document. This member is
mutually exclusive with "values".
description
(string, mandatory) The purpose of this parameter.
values
(object, optional) The accepted values of this parameter, unlisted
values *SHOULD* not be accepted by the parameter. Each key within
this object specifies an accepted value, and its value provides a
description of the purpose of the value.
8. Fortune Heuristics Report Request and Response
8.1. Fortune Heuristics Report Request
A request using the HTTP "DIVINE" method and the "application/json"
type *MUST* be sent to the fortune heuristic endpoint to retrieve
results for a fortune heuristic query.
The request made *MUST* conform to the specifications of the
endpoint, as retrieved via the "SEEK" method described in
Section 7.1.
An example of a request is provided below.
URI: /divination/astrology
Method: DIVINE
Content-Type: application/json
Content-Language: en
{
"birthday": "1976-02-11T00:00:00Z",
"targetDateBegin": "2018-01-01T00:00:00Z",
"targetDateEnd": "2019-01-01T00:00:00Z",
"interval": "M"
}
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8.2. Fortune Heuristics Report Response
A fortune heuristic query using the "DIVINE" method triggers a
response that contains a fortune heuristics report.
A successful response returns a JSON object that *MUST* conform to
the object structure described in this section.
A report object *SHOULD* contain the following members:
type
(URI, mandatory) A URI that defines the type of the report located
at the "report" key of this object.
report
(object, mandatory) An object that contains two keys, "intervals"
and "events". The "intervals" object contains an array of
interval objects that matches the demanded intervals in the
request within the target date range. The "events" object
contains an array of significant event objects within the target
date range.
An example of a response is provided below.
URI: /divination/astrology
Method: DIVINE
HTTP/1.1 200 Success
Content-Type: application/json
Content-Language: en
{
"type": "https://association-of.astrology/reports/monthly",
"report": {
"intervals": [
{
"dateStart": "2018-01-01T00:00:00Z",
"dateEnd": "2018-02-01T00:00:00Z",
"categories": [
{
"category":
"https://divine.example.com/astrology/categories/health"
"value": 80,
"description": "Charge ahead with excellent health."
},
{
"category":
"https://divine.example.com/astrology/categories/love"
"value": 70,
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"description":
"Give a certain person or situation another try!"
},
{
"category":
"https://divine.example.com/astrology/categories/finance"
"value": 5,
"description": "You've just realized that you don't have
any cash on hand."
}
]
},
{
"dateStart": "2018-02-01T00:00:00Z",
"dateEnd": "2018-03-01T00:00:00Z",
"..."
},
"..."
],
"events": [
{
"dateStart": "2018-01-15T03:20:00",
"dateEnd": "2018-01-16T20:22:15",
"description": "The planet of growth and good luck, Jupiter
will make a harmonious connection with power planet Pluto,
helping you connect with influential people",
"recommendation": "Engage in networking during this time."
},
{
"dateStart": "2018-03-22T00:12:40",
"dateEnd": "2018-03-28T02:45:03",
"description": "Communication planet Mercury enters your sign,
which will find you in a busier and chattier mood.",
"recommendation":
"Take charge of work with your newfound energy."
}
"..."
]
}
}
Fortune heuristic reports are created by a divination output that
*MAY* requires quantitative interpretation. A sample representation
of interpreting a graphical divination output is provided in
Figure 2.
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0000000000000000000000000
0000000000000000000000001 G 1000000000000000000000000
0000000000000000000000011 R 1100000000000000000000000
0000000000000000000000111 A 1110000000000000000000000
0000000000000000000001111 C 1111000000000000000000000
0000000000000000000011111 E 1111100000000000000000000
0000000000000000000111111 , 1111110000000000000000000
0000000000000000001111111 1111111000000000000000000
0000000011111111111111111 M 1111111111111111100000000
0000000111111111111111111 E 1111111111111111110000000
0000001111111111111111111 R 1111111111111111111000000
0000011111111111111111111 C 1111111111111111111100000
0000111111111111111111111 Y 1111111111111111111110000
0001111111111111111111111 , 1111111111111111111111000
0011111111111111111111111 1111111111111111111111100
0111111111111111111111111 A 1111111111111111111111110
0000000000000000011111111 N 1111111100000000000000000
0000000000000000111111111 D 1111111110000000000000000
0000000000000001111111111 1111111111000000000000000
0000000000000011111111111 P 1111111111100000000000000
0000000000000111111111111 E 1111111111110000000000000
0000000000001111111111111 A 1111111111111000000000000
0000000000011111111111111 C 1111111111111100000000000
0000000000111111111111111 E 1111111111111110000000000
0000000001111111111111111 . 1111111111111111000000000
Figure 2: Forty-nine yarrow sticks reveals a mystical message on
fortune
8.3. Report Interval Object
The "intervals" value of a report object contains a number of report
intervals -- each representing a non-overlapping period of the
selected interval length. When all of these intervals are put
together, the combined period *MUST* fully cover the requested report
target period.
An example interval object is shown below.
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{
"dateStart": "2018-01-01T00:00:00Z",
"dateEnd": "2018-02-01T00:00:00Z",
"categories": [
{
"category":
"https://divine.example.com/astrology/categories/health"
"value": 80,
"description": "Charge ahead with your excellent health."
},
{
"category":
"https://divine.example.com/astrology/categories/love"
"value": 70,
"description": "Give a certain person or situation another try!"
},
{
"category":
"https://divine.example.com/astrology/categories/finance"
"value": 5,
"description": "You've just realized that you don't have
any cash on hand."
}
]
}
An interval object *MUST* contain the following members:
dateStart
(datetime, mandatory) This value specifies the start of the period
which this interval object applies to.
dateEnd
(datetime, mandatory) This value specifies the end of the period
which this interval object applies to.
In the given example, the "categories" key is an implementation
specific object that details heuristic results returned by the
selected algorithm. This *MAY* differ in different algorithms.
8.4. Report Events Object
The "events" value of a report object contains a number of event
objects. Each event object represents an event relevant to the
calculation of fortune heuristics during a target report period.
These events *MAY* be of variable time lengths, and *MAY* be
overlapping amongst each other.
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The following example demonstrates two event objects the service
determines relevant to a user's query.
{
"dateStart": "2018-01-15T03:20:00",
"dateEnd": "2018-01-16T20:22:15",
"description": "The planet of growth and good luck, Jupiter will
make a harmonious connection with power planet Pluto, helping you
connect with influential people",
"recommendation": "Engage in networking during this time."
},
{
"dateStart": "2018-03-22T00:12:40",
"dateEnd": "2018-03-28T02:45:03",
"description": "Communication planet Mercury enters your sign,
which will find you in a busier and chattier mood.",
"recommendation": "Take charge of work with your newfound energy."
}
Similar to an interval object, an event object *MUST* contain the
following members:
dateStart
(datetime, mandatory) This value specifies the start of the period
described by the event.
dateEnd
(datetime, mandatory) This value specifies the end of the period
described by the event.
In the given example, the keys "description" and "recommendation" are
implementation-specific details. This *MAY* differ in different
algorithms.
8.5. Report Generation Errors
This specification makes use of normal HTTP error codes with the
following extensions.
Errors *MUST* be returned using the Problem JSON Structure as
accordance with [RFC7807].
422 Unprocessable Entity
For example, a malformed date-time parameter, or an illogical
input, such as when the subject's birthday occurs after the report
target date period.
473 Beyond Existing Capability
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The service determines that the outcome is too difficult to
predict. For example, in the case where the calculation is too
complex to complete in a certain time period. The service
*SHOULD* issue this response code to indicate that the client
should not try the same request again.
474 Outcome Impossible
The service determines that the outcome is impossible. For
example, when the algorithm determines that the subject will have
deceased before the start of the requested target period.
9. Security Considerations
o TLS [RFC5246] and authenticated HTTP requests should be used to
protect the DIVINE request and responses due to the personal
nature of information transmitted.
o A client *SHOULD* verify the identity of the server on every
request to prevent impersonation or man-in-the-middle attacks, as
data transmitted to and from the server is sensitive information,
and at times critical information to the user.
o Synchronization of client and server time *MUST* be well-
considered in the implementation of this specification. A
mismatch of client and server time *MAY* lead to algorithm
miscalculations that can cause mistaken choices of a user that
depends on the reliability of this system.
10. IANA Considerations
10.1. Well-Known URI Registrations
This document defines a well-known URI using the registration
procedure and template from Section 5.1 of [RFC5785].
10.1.1. "fortune" Well-Known URI Registration
URI suffix
fortune
Change controller
IETF
Specification document(s)
This document
Related information
N/A.
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11. References
11.1. Normative References
[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>.
[RFC5785] Nottingham, M. and E. Hammer-Lahav, "Defining Well-Known
Uniform Resource Identifiers (URIs)", RFC 5785,
DOI 10.17487/RFC5785, April 2010,
<https://www.rfc-editor.org/info/rfc5785>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[RFC7234] Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
Ed., "Hypertext Transfer Protocol (HTTP/1.1): Caching",
RFC 7234, DOI 10.17487/RFC7234, June 2014,
<https://www.rfc-editor.org/info/rfc7234>.
[RFC7807] Nottingham, M. and E. Wilde, "Problem Details for HTTP
APIs", RFC 7807, DOI 10.17487/RFC7807, March 2016,
<https://www.rfc-editor.org/info/rfc7807>.
[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>.
11.2. Informative References
[ISO.8601-1.2018]
ISO/IEC, "ISO/DIS 8601-1:2018, Data elements and
interchange formats -- Information interchange --
Representation of dates and times -- Part 1: Basic rules",
January 2018,
<https://www.iso.org/en/standard/70907.html>.
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[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>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
Appendix A. Acknowledgements
The authors thank the following individuals for their valuable
feedback on this specification, and commend them for making fortune
heuristics more accessible for the benefit of mankind.
Authors' Addresses
Gabriel Destiny
Divination Inc.
9288 N Divine Street
Dunn, NC 28334
United States of America
Email: gabriel.destiny@ribose.com
Charise Luck
Divination Inc.
9288 N Divine Street
Dunn, NC 28334
United States of America
Email: charise.luck@ribose.com
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