Network Working Group C. Daboo
Internet-Draft Apple
Intended status: Standards Track July 13, 2008
Expires: January 14, 2009
IMAP METADATA Extension
draft-daboo-imap-annotatemore-14
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Abstract
The METADATA extension to the Internet Message Access Protocol
permits clients and servers to maintain "annotations" or "meta data"
on IMAP servers. It is possible to have annotations on a per-mailbox
basis or on the server as a whole. For example, this would allow
comments about the purpose of a particular mailbox to be "attached"
to that mailbox, or a "message of the day" containing server status
information to be made available to anyone logging in to the server.
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Table of Contents
1. Introduction and Overview . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 3
3. Data Model . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Namespace of entries . . . . . . . . . . . . . . . . . . . 4
3.2.1. Entry Names . . . . . . . . . . . . . . . . . . . . . 5
3.3. Private versus Public and Access Control . . . . . . . . . 6
4. IMAP Protocol Changes . . . . . . . . . . . . . . . . . . . . 6
4.1. General Considerations . . . . . . . . . . . . . . . . . . 7
4.2. GETMETADATA Command . . . . . . . . . . . . . . . . . . . 8
4.3. SETMETADATA Command . . . . . . . . . . . . . . . . . . . 9
4.4. METADATA Response . . . . . . . . . . . . . . . . . . . . 11
4.4.1. METADATA response with values . . . . . . . . . . . . 11
4.4.2. Unsolicited METADATA response without values . . . . . 12
5. Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . . 12
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
6.1. Entry and Attribute Registration Template . . . . . . . . 14
6.2. Server Entry Registrations . . . . . . . . . . . . . . . . 14
6.2.1. /public/comment . . . . . . . . . . . . . . . . . . . 15
6.2.2. /public/admin . . . . . . . . . . . . . . . . . . . . 15
6.3. Mailbox Entry Registrations . . . . . . . . . . . . . . . 15
6.3.1. /public/comment . . . . . . . . . . . . . . . . . . . 16
6.3.2. /private/comment . . . . . . . . . . . . . . . . . . . 16
7. Security Considerations . . . . . . . . . . . . . . . . . . . 16
8. Normative References . . . . . . . . . . . . . . . . . . . . . 17
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 17
Appendix B. Change History (to be removed prior to
publication as an RFC) . . . . . . . . . . . . . . . 17
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 21
Intellectual Property and Copyright Statements . . . . . . . . . . 22
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1. Introduction and Overview
The goal of the METADATA extension is to provide a means for clients
to set and retrieve "annotations" or "meta data" on an IMAP server.
The annotations can be associated with specific mailboxes or the
server as a whole. The server can choose to support only server
annotations or both server and mailbox annotations.
A server that supports both server and mailbox annotations indicates
the presence of this extension by returning "METADATA" as one of the
supported capabilities in the CAPABILITY command response.
A server that supports only server annotations indicates the presence
of this extension by returning "METADATA-SERVER" as one of the
supported capabilities in the CAPABILITY command response.
A server that supports unsolicited annotation change responses
indicates the presence of that feature by returning "METADATA-
UNSOLICITED" as one of the supported capabilities in the CAPABILITY
command response. The "ENABLE" [RFC5161] extension MUST also be
present if the "METADATA-UNSOLICITED" capability is advertised.
The METADATA extension adds two new commands and one new untagged
response to the IMAP base protocol.
This extension makes the following changes to the IMAP protocol:
o adds a new SETMETADATA command
o adds a new GETMETADATA command
o adds a new METADATA untagged response
o adds a new METADATA response code
Text comparisons may be done as part of the GETMETADATA command. If
the COMPARATOR [I-D.ietf-imapext-i18n] extension is present, then
comparisons are done using the comparator in effect at the time. If
the COMPARATOR extension is not present, then comparisons MUST use
the i;unicode-casemap comparator, as defined in [RFC5051].
The rest of this document describes the data model and protocol
changes more rigorously.
2. Conventions Used in This Document
In examples, "C:" and "S:" indicate lines sent by the client and
server respectively.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
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"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Whitespace and line breaks have been added to the examples in this
document to promote readability.
3. Data Model
3.1. Overview
Mailboxes or the server as a whole may have zero or more annotations
associated with them. An annotation contains a uniquely named entry
each of which has a value. Annotations can be added to mailboxes
when a mailbox name is provided as the first argument to the
SETMETADATA command, or to the server as a whole when the empty
string is provided as the first argument to the command.
For example, a general comment being added to a mailbox may have an
entry name of "/comment" and a value "Really useful mailbox".
The protocol changes to IMAP described below allow a client to access
or change the values of any annotation entry, assuming it has
sufficient access rights to do so.
3.2. Namespace of entries
Each annotation is an entry that has a hierarchical name, with each
component of the name separated by a slash ("/"). An entry name MUST
NOT contain two consecutive "/" characters and MUST NOT end with a
"/" character.
The value of an entry is NIL (has no value), or a string or binary
data of zero or more octets. A string MAY contain multiple lines of
text. Clients MUST use the CRLF (0x0D 0x0A) character octet sequence
to represent line ends in a multi-line string value.
Entry names MUST NOT contain asterisk ("*") or percent ("%")
characters and MUST NOT contain non-ASCII characters or the NUL
octet. Invalid entry names result in a BAD response in any IMAP
commands where they are used.
Entry names are case-insensitive.
Use of control or punctuation characters in entry names is strongly
discouraged.
This specification defines an initial set of entry available for use
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with mailbox and server annotations. In addition an extension
mechanism is described to allow additional names to be added for
extensibility.
The first component in entry names defines the scope of the
annotation. Currently only the prefixes "/private" or "/public" are
defined. These prefixes are used to indicate whether an annotation
is stored on a per-user basis ("/private") and not visible to other
users, or whether an annotation is shared between authorized users
("/public") with a single value that can be read and changed by
authorized users with appropriate access. See Section 3.3 for
details.
3.2.1. Entry Names
Entry names MUST be specified in a standards track or IESG approved
experimental RFC, or fall under the vendor namespace. See
Section 6.1 for the registration template.
3.2.1.1. Server Entries
These entries are set or retrieved when the mailbox name argument to
the new SETMETADATA or GETMETATDATA commands is the empty string.
/public/comment
Defines a comment or note associated with the server shared with
authorized users of the server.
/public/admin
Indicates a method for contacting the server administrator. The
value MUST be a URI (e.g., a mailto: or tel: URL). This entry is
always read-only - clients cannot change it. It is visible to
authorized users of the system.
/public/vendor/<vendor-token>
Defines the top-level of public entries associated with the server
as created by a particular product of some vendor. This entry can
be used by vendors to provide server or client specific
annotations. The vendor-token MUST be registered with IANA, using
the ACAP [RFC2244] vendor subtree registry.
/private/vendor/<vendor-token>
Defines the top-level of private entries associated with the
server as created by a particular product of some vendor. This
entry can be used by vendors to provide server or client specific
annotations. The vendor-token MUST be registered with IANA, using
the ACAP [RFC2244] vendor subtree registry.
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3.2.1.2. Mailbox Entries
These entries are set or retrieved when the mailbox name argument to
the new SETMETADATA or GETMETADATA commands is not the empty string.
/public/comment
Defines a public comment or note associated with a mailbox.
/private/comment
Defines a private (per-user) comment or note associated with a
mailbox.
/public/vendor/<vendor-token>
Defines the top-level of public entries associated with a specific
mailbox as created by a particular product of some vendor. This
entry can be used by vendors to provide client specific
annotations. The vendor-token MUST be registered with IANA, using
the ACAP [RFC2244] vendor subtree registry.
/private/vendor/<vendor-token>
Defines the top-level of private entries associated with a
specific mailbox as created by a particular product of some
vendor. This entry can be used by vendors to provide client
specific annotations. The vendor-token MUST be registered with
IANA, using the ACAP [RFC2244] vendor subtree registry.
3.3. Private versus Public and Access Control
A user can only set and retrieve private or public annotations on a
mailbox which exists and is returned to them via a LIST or LSUB
command, irrespective of whether they have read or write access to
the actual message content of the mailbox. If the client attempts to
set or retrieve annotations on other mailboxes, the server MUST
respond with a NO response.
If the METADATA extension is present, support for public annotations
is REQUIRED, whilst support for private annotations is OPTIONAL.
This recognizes the fact that support for private annotations may
introduce significantly more complexity to a server in terms of
tracking ownership of the annotations, how quota is determined for
users based on their own annotations etc.
4. IMAP Protocol Changes
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4.1. General Considerations
The new SETMETADATA command and the METADATA response each have a
mailbox name argument. An empty string is used for the mailbox name
to signify server annotations. A non-empty string is used to signify
mailbox annotations attached to the corresponding mailbox.
Servers SHOULD ensure that mailbox annotations are automatically
moved when the mailbox they refer to is renamed, i.e. the annotations
follow the mailbox. This applies to a rename of the INBOX, with the
additional behavior that the annotations are copied from the original
INBOX to the renamed mailbox. i.e. mailbox annotations are preserved
on the INBOX when it is renamed.
Servers SHOULD delete annotations for a mailbox when the mailbox is
deleted, so that a mailbox created with the same name as a previously
existing mailbox does not inherit the old mailbox annotations.
Servers SHOULD allow annotations on all 'types' of mailbox, including
ones reporting \Noselect for their LIST response. Servers can
implicitly remove \Noselect mailboxes when all child mailboxes are
removed, and as such any annotations associated with the \Noselect
mailbox SHOULD be removed.
The server is allowed to impose limitations on the size of any one
annotation or the total number of annotations for a single mailbox or
for the server as a whole. However, the server MUST accept a minimum
annotation data size of at least 1024 bytes, and a minimum annotation
count per server or mailbox of at least 10.
Some annotations may be "read-only" - i.e. they are set by the server
and cannot be changed by the client. Also, such annotations may be
"computed" - i.e. the value changes based on underlying properties of
the mailbox or server. For example, an annotation reporting the
total size of all messages in the mailbox would change as messages
are added or removed. Or, an annotation containing an IMAP URL for
the mailbox would change if the mailbox was renamed.
Servers MAY support sending unsolicited responses for use when
annotations are changed by some "third-party" (see Section 4.4).
Servers indicate their ability to do that by advertising the
"METADATA-UNSOLICITED" capability and supporting the ENABLE command.
Servers MUST only send unsolicited responses if the client used the
ENABLE command [RFC5161] extension with the capability string
"METADATA-UNSOLICITED" earlier in the session.
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4.2. GETMETADATA Command
This extension adds the GETMETADATA command. This allows clients to
retrieve server or mailbox annotations.
This command is only available in authenticated or selected state
[RFC3501].
Arguments: mailbox-name
entry-specifier
Responses: required METADATA response
Result: OK - command completed
NO - command failure: can't access annotations on
the server
BAD - command unknown or arguments invalid
When the mailbox name is the empty string, this command retrieves
server annotations. When the mailbox name is not empty, this command
retrieves annotations on the specified mailbox.
Example:
C: a GETMETADATA "" /public/comment
S: * METADATA "" (/public/comment "Shared comment")
S: a OK GETMETADATA complete
In the above example, the contents of the value of the "/public/
comment" server entry is requested by the client and returned by
the server.
Example:
C: a GETMETADATA "INBOX" /private/comment
S: * METADATA "INBOX" (/private/comment "My own comment")
S: a OK GETMETADATA complete
In the above example, the contents of the value of the "/private/
comment" mailbox entry for the mailbox "INBOX" is requested by the
client and returned by the server.
Entry specifiers can be lists of atomic specifiers, so that multiple
annotations may be returned in a single GETMETADATA command.
Example:
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C: a GETMETADATA "INBOX" (/public/comment /private/comment)
S: * METADATA "INBOX" (/public/comment "Shared comment"
/private/comment "My own comment")
S: a OK GETMETADATA complete
In the above example, the values of the two server entries
"/public/comment" and "/private/comment" on the mailbox "inbox"
are requested by the client and returned by the server.
4.3. SETMETADATA Command
This extension adds the SETMETADATA command. This allows clients to
set annotations.
This command is only available in authenticated or selected state
[RFC3501].
Arguments: mailbox-name
entry
value
list of entry, values
Responses: no specific responses for this command
Result: OK - command completed
NO - command failure: can't set annotations,
or annotation too big or too many
BAD - command unknown or arguments invalid
This command sets the specified list of entries by adding or
replacing the specified values provided, on the specified existing
mailboxes or on the server (if the mailbox argument is the empty
string). Clients can use NIL for the value of entries it wants to
remove. The server SHOULD NOT return a METADATA response containing
the updated annotation data. Clients MUST NOT assume that a METADATA
response will be sent, and MUST assume that if the command succeeds
then the annotation has been changed.
If the server is unable to set an annotation because the size of its
value is too large, the server MUST return a tagged NO response with
a "[METADATA MAXSIZE NNN]" response code when NNN is the maximum
octet count that it is willingly to accept.
If the server is unable to set a new annotation because the maximum
number of allowed annotations has already been reached, the server
MUST return a tagged NO response with a "[METADATA TOOMANY]" response
code.
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If the server is unable to set a new annotation because it does not
support private annotations on one of the specified mailboxes, the
server MUST return a tagged NO response with a "[METADATA NOPRIVATE]"
response code.
When any one annotation fails to be set, resulting in a tagged NO
response from the server, then the server MUST NOT change the values
for other annotations specified in the SETMETADATA command.
Example:
C: a SETMETADATA INBOX (/private/comment {33}
S: + ready for data
My new comment across
two lines.
)
S: a OK SETMETADATA complete
In the above example, the entry "/private/comment" for the mailbox
"INBOX" is created (if not already present) and the value set to a
multi-line string.
Example:
C: a SETMETADATA INBOX (/private/comment NIL)
S: a OK SETMETADATA complete
In the above example, the entry "/private/comment" is removed from
the mailbox "INBOX".
Multiple entries can be set in a single SETMETADATA command by
listing entry-value pairs in the list.
Example:
C: a SETMETADATA INBOX (/private/comment "My new comment"
/public/comment "This one is for you!")
S: a OK SETMETADATA complete
In the above example, the entries "/private/comment" and "/public/
comment" for the mailbox "INBOX" are created (if not already
present) and the values set as specified.
Example:
C: a SETMETADATA INBOX (/private/comment "My new comment")
S: a NO [METADATA TOOMANY] SETMETADATA failed
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In the above example, the server is unable to set the requested
(new) annotation as it has reached the limit on the number of
annotations it can support on the specified mailbox.
4.4. METADATA Response
The METADATA response displays results of a GETMETADATA command, or
can be returned as an unsolicited response at anytime by the server
in response to a change in a server or mailbox annotation.
When unsolicited responses are activated by the ENABLE [RFC5161]
command for this extension, servers MUST send unsolicited METADATA
responses if server or mailbox annotations are changed by a third-
party, allowing servers to keep clients updated with changes.
Unsolicited METADATA responses MUST only contain entry names, not the
values. If the client wants to update any cached values it must
explicitly retrieve those using a GETMETADATA command.
The METADATA response can contain multiple entries in a single
response, but the server is free to return multiple responses for
each entry or group of entries if it desires.
This response is only available in authenticated or selected state
[RFC3501].
4.4.1. METADATA response with values
The response consists of a list of entry-value pairs.
Example:
C: a GETMETADATA "" /public/comment
S: * METADATA "" (/public/comment "My comment")
S: a OK GETMETADATA complete
In the above example, a single entry with its value is returned by
the server.
Example:
C: a GETMETADATA "INBOX" /private/comment /public/comment
S: * METADATA "INBOX" (/private/comment "My comment"
/public/comment "Its sunny outside!")
S: a OK GETMETADATA complete
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In the above example, two entries and their values are returned by
the server.
Example:
C: a GETMETADATA "INBOX" /private/comment /public/comment
S: * METADATA "INBOX" (/private/comment "My comment")
S: * METADATA "INBOX" (/public/comment "Its sunny outside!")
S: a OK GETMETADATA complete
In the above example, the server returns two separate responses
for each of the two entries requested.
4.4.2. Unsolicited METADATA response without values
The response consists of a list of entries, each of which have
changed on the server or mailbox.
Example:
C: a NOOP
S: * METADATA "" /public/comment
S: a OK NOOP complete
In the above example, the server indicates that the "/public/
comment" server entry has been changed.
Example:
C: a NOOP
S: * METADATA "INBOX" /public/comment /private/comment
S: a OK NOOP complete
In the above example, the server indicates a change to two mailbox
entries.
5. Formal Syntax
The following syntax specification uses the Augmented Backus-Naur
Form (ABNF) notation as specified in [RFC5234].
Non-terminals referenced but not defined below are as defined by
[RFC3501] with the new definitions in [RFC4466] superseding those in
[RFC3501].
Except as noted otherwise, all alphabetic characters are case-
insensitive. The use of upper or lower case characters to define
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token strings is for editorial clarity only. Implementations MUST
accept these strings in a case-insensitive fashion.
capability =/ "METADATA" / "METADATA-SERVER" /
"METADATA-UNSOLICITED"
; defines the capabilities for this extension
command-auth =/ setmetadata / getmetadata
; adds to original IMAP command
entries = entry /
"(" entry *(SP entry) ")"
; entry specifiers
entry = astring
; slash-separated path to entry
; MUST NOT contain "*" or "%"
entry-value = entry SP value
entry-values = "(" entry-value *(SP entry-value) ")"
entry-list = entry *(SP entry)
; list of entries used in unsolicited
; METADATA response
getmetadata = "GETMETADATA" SP mailbox SP entries
; empty string for mailbox implies
; server annotation.
metadata-resp = "METADATA" SP mailbox SP
(entry-values / entry-list)
; empty string for mailbox implies
; server annotation.
response-payload =/ metadata-resp
; adds to original IMAP data responses
resp-text-code =/ "METADATA" SP ("MAXSIZE" SP number /
"TOOMANY" / "NOPRIVATE")
; new response codes for SETMETADATA
; failures
setmetadata = "SETMETADATA" SP mailbox
SP entry-values
; empty string for mailbox implies
; server annotation.
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value = nstring / literal8
6. IANA Considerations
Entry names MUST be specified in a standards track or IESG approved
experimental RFC, or fall under the vendor namespace. All entries
MUST have either "/public" or "/private" as a prefix.
Each entry registration MUST include a content-type that is used to
indicate the nature of the annotation value. Where applicable a
charset parameter MUST be included with the content-type.
6.1. Entry and Attribute Registration Template
To: iana@iana.org
Subject: IMAP METADATA Entry Registration
Type: [Either "Mailbox" or "Server"]
Name: [the name of the entry]
Description: [a description of what the entry is for]
Content-type: [MIME Content-Type and charset for the entry value]
RFC Number: [for entries published as RFCs]
Contact: [email and/or physical address to contact for
additional information]
6.2. Server Entry Registrations
The following templates specify the IANA registrations of annotation
entries specified in this document.
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6.2.1. /public/comment
To: iana@iana.org
Subject: IMAP METADATA Entry Registration
Type: Server
Name: /public/comment
Description: Defines a comment or note associated with the server
shared with authorized users of the server.
Content-type: text/plain; charset=utf-8
RFC Number: This RFC.
Contact: IMAP Extensions <ietf-imapext@imc.org>
6.2.2. /public/admin
To: iana@iana.org
Subject: IMAP METADATA Entry Registration
Type: Server
Name: /public/admin
Description: Indicates a method for contacting the server
administrator. The value MUST be a URI (e.g., a
mailto: or tel: URL). This entry is always
read-only - clients cannot change it. It is visible
to authorized users of the system.
Content-type: text/plain; charset=utf-8
RFC Number: This RFC.
Contact: IMAP Extensions <ietf-imapext@imc.org>
6.3. Mailbox Entry Registrations
The following templates specify the IANA registrations of annotation
entries specified in this document.
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6.3.1. /public/comment
To: iana@iana.org
Subject: IMAP METADATA Entry Registration
Type: Mailbox
Name: /public/comment
Description: Defines a public comment or note associated with a
mailbox.
Content-type: text/plain; charset=utf-8
RFC Number: This RFC.
Contact: IMAP Extensions <ietf-imapext@imc.org>
6.3.2. /private/comment
To: iana@iana.org
Subject: IMAP METADATA Entry Registration
Type: Mailbox
Name: /private/comment
Description: Defines a private comment or note associated with a
mailbox.
Content-type: text/plain; charset=utf-8
RFC Number: This RFC.
Contact: IMAP Extensions <ietf-imapext@imc.org>
7. Security Considerations
Annotations can contain arbitrary data of varying size. As such
servers MUST ensure that size limits are enforced to prevent a user
from using up all available space on a server and preventing use by
others. Clients MUST treat annotation data values as an "untrusted"
source of data as it is possible for it to contain malicious content.
Annotations whose values are intended to remain private MUST be
stored only in entries that have the "/private" prefix on the entry
name. Servers MUST ensure that /private annotations are only visible
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to the user that created them.
Excluding the above issues the METADATA extension does not raise any
security considerations that are not present in the base IMAP
protocol, and these issues are discussed in [RFC3501].
8. Normative References
[I-D.ietf-imapext-i18n]
Newman, C., Gulbrandsen, A., and A. Melnikov, "Internet
Message Access Protocol Internationalization",
draft-ietf-imapext-i18n-15 (work in progress),
February 2008.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2244] Newman, C. and J. Myers, "ACAP -- Application
Configuration Access Protocol", RFC 2244, November 1997.
[RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
4rev1", RFC 3501, March 2003.
[RFC4466] Melnikov, A. and C. Daboo, "Collected Extensions to IMAP4
ABNF", RFC 4466, April 2006.
[RFC5051] Crispin, M., "i;unicode-casemap - Simple Unicode Collation
Algorithm", RFC 5051, October 2007.
[RFC5161] Gulbrandsen, A. and A. Melnikov, "The IMAP ENABLE
Extension", RFC 5161, March 2008.
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, January 2008.
Appendix A. Acknowledgments
The ideas expressed in this document are based on the message
annotation document that was co-authored by Randall Gellens. The
participants of the IMAPext working group made significant
contributions to this work.
Appendix B. Change History (to be removed prior to publication as an
RFC)
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Changes from -13 to -14:
1. Add statement that no annotations are set when any one fails in a
single SETMETADATA command.
2. Make unsolicited responses a MUST when ENABLE is used, but make
support for ENABLE METADATA optional so servers aren't required
to do unsolicited responses. This required a new capbility for
the unsolicited behavior.
3. Re-ordered Security considerations paragraphs and added
additional text about the possibility of malicious content in
data values. [SECDIR suggestion]
4. Reworded "all users" to "authorized users" in appropriate places.
[SECDIR suggestion]
5. Added addition text to Security considerations about the need for
servers to keep /private annotations private to the user that
created them. [SECDIR suggestion]
6. Added comment that string values can be multi-line and that CRLF
must be the line end indicator. Also changes one example to be
multi-line. [SECDIR suggestion]
Changes from -12 to -13:
1. Major changes to simplify things.
2. Removed dependency on LISTEXT - GETMETADATA now used to get
annotations on mailboxes.
3. Changed data model to remove attributes - annotations are now
only entry-value pairs.
4. Removed all wildcard behavior on entry names.
5. Cut down the registered annotations to only a few essential ones.
Changes from -11 to -12:
1. Allow server annotations to be used without mailbox annotations.
2. Require i;unicode-casemap when COMPARATOR is not present.
3. Use ENABLE to turn on unsolicited responses.
4. Use formal syntax elements from SORT/THREAD extensions to define
the values for /sort and /thread entries.
5. Added a comment that use of IDLE is preferred even when /check
is true.
6. Use formal syntax element from base spec for the /size value.
7. Removed IANA registration for attributes as we don't expect any
more to be defined.
8. Tweaked IANA registration template to be more compact and add
RFC Number reference.
9. Some minor re-phrasing was done.
10. Added text about handling of annotations on INBOX when it is
renamed.
11. Require a BAD response when an unknown collation is used in
LISTEXT selection option.
Changes from -10 to -11:
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1. Added new paragraph to indicate that values may be read-only or
computed.
2. /admin server annotation value now must be a URI.
3. Clarified that SORT and THREAD extensions are not required.
4. Fixed use of undefined entries in some examples.
5. Fixed many examples.
6. Added IANA registration for LIST-EXTENDED items.
7. Added match type and collation identifier to the LIST-EXTENDED
selection option.
8. Made support for IMAP-I18N a requirement.
9. Minor text clarifications applied.
10. Remove mailbox list set atomicity requirement.
11. Clarified that annotations can only be set on mailboxes that
actually exist.
Changes from -09 to -10:
1. Updated to rfc 4466 reference.
2. Reworded data model description.
3. Reworked LIST-EXTENDED so that responses have metadata items
after the mailbox info.
4. Various spelling fixes.
Changes from -08 to -09:
1. Remove content-language attribute and reference.
2. Changed capability and command names.
3. Revised abstract.
Changes from -07 to -08:
1. Changed 'string' formal syntax to 'list-mailbox' and 'astring'
for entry/attribute names.
2. Updated examples to match new astring syntax.
3. Changed CAPABILITY name due to incompatible syntax change.
4. Removed content-type attribute.
5. Added Content-type to IANA registration for entries.
6. Removed vendor attributes.
7. Fixed examples in section 3.3 for multi-mailbox and multi-entry
cases.
8. Removed wildcards for attributes.
9. Entry/attributes can now only be ASCII.
10. Tied up text wrt storing/fetching.
11. Added Conventions section
12. Entry/attributes MUST NOT contain consecutive or trailing '/' or
'.'.
13. Changed to use IMAP ABNF extensions document for some formal
syntax items.
Changes from -06 to -07:
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1. Reworded /checkperiod item.
2. Clarified unsolicited response behavior.
Changes from -05 to -06:
1. Removed 'modifiedsince' attribute as there is currently no use
for it.
2. Added content-language attribute.
3. Changed access to allow .priv and .shared on any mailbox returned
by LIST/LSUB.
4. Added IANA registrations for items defined in this document.
5. Added latest IPR statement.
6. Updated references.
Changes from -04 to -05:
1. Fix for valid IMAP state of commands.
2. Fix formatting, ID nits etc.
Changes from -03 to -04:
1. Allow retrieval of shared annotations for READ-ONLY mailbox.
2. Clarification of annotation loss on implicit removal of \Noselect
mailboxes.
3. Now requires roll-back of all changes to matching mailboxes if
there is a partial failure in SETANNOTATION.
Changes from -02 to -03:
1. Reworked entry naming scheme to split out mailbox name and use
empty string for server items.
Changes from -01 to -02:
1. SETANNOTATION lists use (..).
2. Explicitly state behavior of unsolicited responses.
3. Adding SHOULD behavior for rename/delete of mailboxes.
4. Added statement about supporting annotations on \Noselect
mailboxes.
5. Cleaned up formal syntax to use IMAP string type for entry and
attributes, with requirements on how the string is formatted.
6. Use of ACAP vendor subtree registry for vendor tokens.
Changes from -00 to -01:
1. Multiple entry-att responses are now simply delimited by spaces
in line with ANNOTATE spec. Adjusted examples to match.
2. Fixed entry-list formal syntax item to account for unsolicited
parenthesized list of entries.
3. Removed setentries formal syntax item for simplicity since its
only used once.
4. Removed reference to 'message annotation' in section 5.1.
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5. Changed formal syntax to restrict top level entries to /server
and /mailbox/{...} only. Re-arranged entry names section to
account for this change.
6. Added comment and example for ANNOTATION response to allow
servers to return separate responses for each entry if desired.
Author's Address
Cyrus Daboo
Apple Inc.
1 Infinite Loop
Cupertino, CA 95014
USA
Email: cyrus@daboo.name
URI: http://www.apple.com/
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Daboo Expires January 14, 2009 [Page 22]
