Internet DRAFT - draft-ietf-jmap-mail
draft-ietf-jmap-mail
JMAP N. Jenkins
Internet-Draft FastMail
Updates: 5788 (if approved) C. Newman
Intended status: Standards Track Oracle
Expires: September 9, 2019 March 8, 2019
JMAP (JSON Meta Application Protocol) for Mail
draft-ietf-jmap-mail-16
Abstract
This document specifies a data model for synchronising email data
with a server using JMAP (the JSON Meta Application Protocol).
Clients can use this to efficiently search, access, organise and send
messages, and get pushed notifications for fast resynchronisation
when new messages are delivered or a change is made in another
client.
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 September 9, 2019.
Copyright Notice
Copyright (c) 2019 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. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
Jenkins & Newman Expires September 9, 2019 [Page 1]
Internet-Draft JMAP Mail March 2019
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Notational conventions . . . . . . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
1.3. Additions to the capabilities object . . . . . . . . . . 5
1.3.1. urn:ietf:params:jmap:mail . . . . . . . . . . . . . . 5
1.3.2. urn:ietf:params:jmap:submission . . . . . . . . . . . 6
1.3.3. urn:ietf:params:jmap:vacationresponse . . . . . . . . 7
1.4. Data type support in different accounts . . . . . . . . . 7
1.5. Push . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.5.1. Example . . . . . . . . . . . . . . . . . . . . . . . 8
1.6. Ids . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2. Mailboxes . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1. Mailbox/get . . . . . . . . . . . . . . . . . . . . . . . 12
2.2. Mailbox/changes . . . . . . . . . . . . . . . . . . . . . 12
2.3. Mailbox/query . . . . . . . . . . . . . . . . . . . . . . 13
2.4. Mailbox/queryChanges . . . . . . . . . . . . . . . . . . 14
2.5. Mailbox/set . . . . . . . . . . . . . . . . . . . . . . . 14
2.6. Example . . . . . . . . . . . . . . . . . . . . . . . . . 14
3. Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.1. Thread/get . . . . . . . . . . . . . . . . . . . . . . . 19
3.1.1. Example . . . . . . . . . . . . . . . . . . . . . . . 19
3.2. Thread/changes . . . . . . . . . . . . . . . . . . . . . 19
4. Emails . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.1. Properties of the Email object . . . . . . . . . . . . . 20
4.1.1. Metadata . . . . . . . . . . . . . . . . . . . . . . 21
4.1.2. Header fields parsed forms . . . . . . . . . . . . . 23
4.1.3. Header fields properties . . . . . . . . . . . . . . 28
4.1.4. Body parts . . . . . . . . . . . . . . . . . . . . . 30
4.2. Email/get . . . . . . . . . . . . . . . . . . . . . . . . 36
4.2.1. Example . . . . . . . . . . . . . . . . . . . . . . . 38
4.3. Email/changes . . . . . . . . . . . . . . . . . . . . . . 39
4.4. Email/query . . . . . . . . . . . . . . . . . . . . . . . 40
4.4.1. Filtering . . . . . . . . . . . . . . . . . . . . . . 40
4.4.2. Sorting . . . . . . . . . . . . . . . . . . . . . . . 42
4.4.3. Thread collapsing . . . . . . . . . . . . . . . . . . 44
4.5. Email/queryChanges . . . . . . . . . . . . . . . . . . . 44
4.6. Email/set . . . . . . . . . . . . . . . . . . . . . . . . 44
4.7. Email/copy . . . . . . . . . . . . . . . . . . . . . . . 47
4.8. Email/import . . . . . . . . . . . . . . . . . . . . . . 47
4.9. Email/parse . . . . . . . . . . . . . . . . . . . . . . . 49
4.10. Examples . . . . . . . . . . . . . . . . . . . . . . . . 51
5. Search snippets . . . . . . . . . . . . . . . . . . . . . . . 58
5.1. SearchSnippet/get . . . . . . . . . . . . . . . . . . . . 59
Jenkins & Newman Expires September 9, 2019 [Page 2]
Internet-Draft JMAP Mail March 2019
5.2. Example . . . . . . . . . . . . . . . . . . . . . . . . . 60
6. Identities . . . . . . . . . . . . . . . . . . . . . . . . . 61
6.1. Identity/get . . . . . . . . . . . . . . . . . . . . . . 62
6.2. Identity/changes . . . . . . . . . . . . . . . . . . . . 62
6.3. Identity/set . . . . . . . . . . . . . . . . . . . . . . 62
6.4. Example . . . . . . . . . . . . . . . . . . . . . . . . . 63
7. Email submission . . . . . . . . . . . . . . . . . . . . . . 63
7.1. EmailSubmission/get . . . . . . . . . . . . . . . . . . . 68
7.2. EmailSubmission/changes . . . . . . . . . . . . . . . . . 68
7.3. EmailSubmission/query . . . . . . . . . . . . . . . . . . 68
7.4. EmailSubmission/queryChanges . . . . . . . . . . . . . . 69
7.5. EmailSubmission/set . . . . . . . . . . . . . . . . . . . 69
7.5.1. Example . . . . . . . . . . . . . . . . . . . . . . . 71
8. Vacation response . . . . . . . . . . . . . . . . . . . . . . 74
8.1. VacationResponse/get . . . . . . . . . . . . . . . . . . 75
8.2. VacationResponse/set . . . . . . . . . . . . . . . . . . 75
9. Security considerations . . . . . . . . . . . . . . . . . . . 75
9.1. EmailBodyPart value . . . . . . . . . . . . . . . . . . . 75
9.2. HTML email display . . . . . . . . . . . . . . . . . . . 76
9.3. Multiple part display . . . . . . . . . . . . . . . . . . 78
9.4. Email submission . . . . . . . . . . . . . . . . . . . . 78
9.5. Partial account access . . . . . . . . . . . . . . . . . 79
9.6. Permission to send from an address . . . . . . . . . . . 79
10. IANA considerations . . . . . . . . . . . . . . . . . . . . . 80
10.1. JMAP capability registration for "mail" . . . . . . . . 80
10.2. JMAP capability registration for "submission" . . . . . 80
10.3. JMAP capability registration for "vacationresponse" . . 81
10.4. IMAP and JMAP keywords registry . . . . . . . . . . . . 81
10.4.1. Registration of JMAP keyword '$draft' . . . . . . . 81
10.4.2. Registration of JMAP keyword '$seen' . . . . . . . . 82
10.4.3. Registration of JMAP keyword '$flagged' . . . . . . 83
10.4.4. Registration of JMAP keyword '$answered' . . . . . . 84
10.4.5. Registration of '$recent' keyword . . . . . . . . . 85
10.5. Registration of "inbox" role in . . . . . . . . . . . . 85
10.6. JMAP Error Codes registry . . . . . . . . . . . . . . . 86
10.6.1. mailboxHasChild . . . . . . . . . . . . . . . . . . 86
10.6.2. mailboxHasEmail . . . . . . . . . . . . . . . . . . 86
10.6.3. blobNotFound . . . . . . . . . . . . . . . . . . . . 86
10.6.4. tooManyKeywords . . . . . . . . . . . . . . . . . . 87
10.6.5. tooManyMailboxes . . . . . . . . . . . . . . . . . . 87
10.6.6. invalidEmail . . . . . . . . . . . . . . . . . . . . 87
10.6.7. tooManyRecipients . . . . . . . . . . . . . . . . . 87
10.6.8. noRecipients . . . . . . . . . . . . . . . . . . . . 88
10.6.9. invalidRecipients . . . . . . . . . . . . . . . . . 88
10.6.10. forbiddenMailFrom . . . . . . . . . . . . . . . . . 88
10.6.11. forbiddenFrom . . . . . . . . . . . . . . . . . . . 89
10.6.12. forbiddenToSend . . . . . . . . . . . . . . . . . . 89
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 89
Jenkins & Newman Expires September 9, 2019 [Page 3]
Internet-Draft JMAP Mail March 2019
11.1. Normative References . . . . . . . . . . . . . . . . . . 89
11.2. Informative References . . . . . . . . . . . . . . . . . 93
11.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 94
1. Introduction
JMAP ([I-D.ietf-jmap-core] - JSON Meta Application Protocol) is a
generic protocol for synchronising data, such as mail, calendars or
contacts, between a client and a server. It is optimised for mobile
and web environments, and aims to provide a consistent interface to
different data types.
This specification defines a data model for accessing a mail store
over JMAP, allowing you to query, read, organise and submit mail for
sending.
The data model is designed to allow a server to provide consistent
access to the same data via IMAP ([RFC3501]) as well as JMAP. As in
IMAP, a message must belong to a mailbox, however in JMAP its id does
not change if you move it between mailboxes, and the server may allow
it to belong to multiple mailboxes simultaneously (often exposed in a
user agent as labels rather than folders).
As in IMAP, emails may also be assigned zero or more keywords: short
arbitrary strings. These are primarily intended to store metadata to
inform client display, such as unread status or whether a message has
been replied to. An IANA registry allows common semantics to be
shared between clients and extended easily in the future.
A message and its replies are linked on the server by a common thread
id. Clients may fetch the list of messages with a particular thread
id to more easily present a threaded or conversational interface.
Permissions for message access happen on a per-mailbox basis.
Servers may give the user restricted permissions for certain
mailboxes, for example if another user's inbox has been shared read-
only with them.
1.1. 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.
Jenkins & Newman Expires September 9, 2019 [Page 4]
Internet-Draft JMAP Mail March 2019
Type signatures, examples and property descriptions in this document
follow the conventions established in section 1.1 of
[I-D.ietf-jmap-core]. Data types defined in the core specification
are also used in this document.
Servers MUST support all properties specified for the new data types
defined in this document.
1.2. Terminology
The same terminology is used in this document as in the core JMAP
specification.
1.3. Additions to the capabilities object
The capabilities object is returned as part of the JMAP Session
object; see [I-D.ietf-jmap-core], section 2.
This document defines three additional capability URIs.
1.3.1. urn:ietf:params:jmap:mail
This represents support for the Mailbox, Thread, Email, and
SearchSnippet data types and associated API methods. The value of
this property in the JMAP session _capabilities_ property is the
empty object.
The value of this property in an account's _accountCapabilities_
property is an object which MUST contain the following information on
server capabilities and permissions for that account:
o *maxMailboxesPerEmail*: "UnsignedInt|null" The maximum number of
mailboxes that can be can assigned to a single Email object (see
section 4). This MUST be an integer >= 1, or "null" for no limit
(or rather, the limit is always the number of mailboxes in the
account).
o *maxMailboxDepth*: "UnsignedInt|null" The maximum depth of the
mailbox hierarchy (i.e. one more than the maximum number of
ancestors a mailbox may have), or "null" for no limit.
o *maxSizeMailboxName*: "UnsignedInt" The maximum length, in (UTF-8)
octets, allowed for the name of a mailbox. This MUST be at least
100, although it is recommended servers allow more.
o *maxSizeAttachmentsPerEmail*: "UnsignedInt" The maximum total size
of attachments, in octets, allowed for a single Email object. A
server MAY still reject import or creation of emails with a lower
Jenkins & Newman Expires September 9, 2019 [Page 5]
Internet-Draft JMAP Mail March 2019
attachment size total (for example, if the body includes several
megabytes of text, causing the size of the encoded MIME structure
to be over some server-defined limit). Note, this limit is for
the sum of unencoded attachment sizes. Users are generally not
knowledgeable about encoding overhead etc., nor should they need
to be, so marketing and help materials normally tell them the "max
size attachments". This is the unencoded size they see on their
hard drive, and so this capability matches that and allows the
client to consistently enforce what the user understands as the
limit. The server may separately have a limit for the total size
of the RFC5322 message, which will have attachments Base64 encoded
and message headers and bodies too. For example, suppose the
server advertises "maxSizeAttachmentsPerEmail: 50000000" (50 MB).
The enforced server limit may be for an RFC5322 size of 70000000
octets (70 MB). Even with Base64 encoding and a 2 MB HTML body,
50 MB attachments would fit under this limit.
o *emailQuerySortOptions*: "String[]" A list of all the values the
server supports for the "property" field of the Comparator object
in an Email/query sort (see section 5.5). This MAY include
properties the client does not recognise (for example custom
properties specified in a vendor extension). Clients MUST ignore
any unknown properties in the list.
o *mayCreateTopLevelMailbox*: "Boolean" If "true", the user may
create a mailbox (see section 2) in this account with a "null"
parentId. (Permission for creating a child of an existing mailbox
is given by the myRights property on that mailbox.)
1.3.2. urn:ietf:params:jmap:submission
This represents support for the Identity and MessageSubmission data
types and associated API methods. The value of this property in the
JMAP session _capabilities_ property is the empty object.
The value of this property in an account's _accountCapabilities_
property is an object which MUST contain the following information on
server capabilities and permissions for that account:
o *maxDelayedSend*: "UnsignedInt" The number in seconds of the
maximum delay the server supports in sending (see the
EmailSubmission object description). This is "0" if the server
does not support delayed send.
o *submissionExtensions*: "String[String[]]" The set of SMTP
submission extensions supported by the server, which the client
may use when creating an EmailSubmission object (see section 7).
Each key in the object is the _ehlo-name_, and the value is a list
Jenkins & Newman Expires September 9, 2019 [Page 6]
Internet-Draft JMAP Mail March 2019
of _ehlo-args_. A JMAP implementation that talks to a Submission
[RFC6409] server SHOULD have a configuration setting that allows
an administrator to modify the set of submission EHLO capabilities
it may expose on this property. This allows a JMAP server to
easily add access to a new submission extension without code
changes. By default, the JMAP server should hide EHLO
capabilities that are to do with the transport mechanism and thus
are only relevant to the JMAP server (for example PIPELINING,
CHUNKING, or STARTTLS). Examples of Submission extensions to
include:
* FUTURERELEASE ([RFC4865])
* SIZE ([RFC1870])
* DSN ([RFC3461])
* DELIVERYBY ([RFC2852])
* MT-PRIORITY ([RFC6710])
A JMAP server MAY advertise an extension and implement the
semantics of that extension locally on the JMAP server even if a
submission server used by JMAP doesn't implement it. The full
IANA registry of submission extensions can be found at
<https://www.iana.org/assignments/mail-parameters/mail-
parameters.xhtml#mail-parameters-2>.
1.3.3. urn:ietf:params:jmap:vacationresponse
This represents support for the VacationResponse data type and
associated API methods. The value of this property is an empty
object in both the JMAP session _capabilities_ property and an
account's _accountCapabilities_ property.
1.4. Data type support in different accounts
The server MUST include the appropriate capability strings as keys in
the _accountCapabilities_ property of any account with which the user
may use the data types represented by that URI. Supported data types
may differ between accounts the user has access to. For example, in
the user's personal account they may have access to all three sets of
data, but in a shared account they may only have data for
"urn:ietf:params:jmap:mail". This means they can access
Mailbox/Thread/Email data in the shared account but are not allowed
to send as that account (and so do not have access to Identity/
MessageSubmission objects) or view/set its vacation response.
Jenkins & Newman Expires September 9, 2019 [Page 7]
Internet-Draft JMAP Mail March 2019
1.5. Push
Servers MUST support the JMAP push mechanisms, as specified in
[I-D.ietf-jmap-core] section 7, to receive notifications when the
state changes for any of the types defined in this specification.
In addition, servers that implement the "urn:ietf:params:jmap:mail"
capability MUST support pushing state changes for a type called
"EmailDelivery". There are no methods to act on this type; it only
exists as part of the push mechanism. The state string for this MUST
change whenever a new Email is added to the store, but SHOULD NOT
change upon any other change to the Email objects, for example if one
is marked as read or deleted.
Clients in battery constrained environments may wish to delay
fetching changes initiated by the user, but fetch new messages
immediately so they can notify the user. To do this, they can
register for pushes for the EmailDelivery type rather than the Email
type (defined in section 4).
1.5.1. Example
The client has registered for push notifications (see
[I-D.ietf-jmap-core]) just for the "EmailDelivery" type. The user
marks an email as read on another device, causing the state string
for the "Email" type to change, however as nothing new was added to
the store the "EmailDelivery" state does not change and nothing is
pushed to the client. A new message arrives in the user's inbox,
again causing the "Email" state to change. This time the
"EmailDelivery" state also changes, and a StateChange object is
pushed to the client with the new state string. The client may then
resync to fetch the new message immediately.
1.6. Ids
If a JMAP Mail server also provides an IMAP interface to the data and
supports [RFC8474] IMAP Extension for Object Identifiers, the ids
SHOULD be the same for mailbox, thread, and email objects in JMAP.
2. Mailboxes
A mailbox represents a named set of emails. This is the primary
mechanism for organising emails within an account. It is analogous
to a folder or a label in other systems. A mailbox may perform a
certain role in the system; see below for more details.
Jenkins & Newman Expires September 9, 2019 [Page 8]
Internet-Draft JMAP Mail March 2019
For compatibility with IMAP, an email MUST belong to one or more
mailboxes. The email id does not change if the email changes
mailboxes.
A *Mailbox* object has the following properties:
o *id*: "Id" (immutable; server-set) The id of the mailbox.
o *name*: "String" User-visible name for the mailbox, e.g. "Inbox".
This MUST be a Net-Unicode string ([RFC5198]) of at least 1
character in length, subject to the maximum size given in the
capability object. There MUST NOT be two sibling mailboxes with
both the same parent and the same name. Servers MAY reject names
that violate server policy (e.g., names containing slash (/) or
control characters).
o *parentId*: "Id|null" (default: null) The mailbox id for the
parent of this mailbox, or "null" if this mailbox is at the top
level. Mailboxes form acyclic graphs (forests) directed by the
child-to-parent relationship. There MUST NOT be a loop.
o *role*: "String|null" (default: null) Identifies mailboxes that
have a particular common purpose (e.g. the "inbox"), regardless of
the _name_ (which may be localised). This value is shared with
IMAP (exposed in IMAP via the [RFC6154] SPECIAL-USE extension).
However, unlike in IMAP, a mailbox MUST only have a single role,
and there MUST NOT be two mailboxes in the same account with the
same role. Servers providing IMAP access to the same data are
encouraged to enforce these extra restrictions in IMAP as well.
Otherwise, it is implementation dependent how to modify the IMAP
attributes to ensure compliance when exposing the data over JMAP.
The value MUST be one of the mailbox attribute names listed in the
IANA IMAP Mailbox Name Attributes Registry [1], as established in
[RFC8457], converted to lower-case. New roles may be established
here in the future. An account is not required to have mailboxes
with any particular roles.
o *sortOrder*: "UnsignedInt" (default: 0) Defines the sort order of
mailboxes when presented in the client's UI, so it is consistent
between devices. The number MUST be an integer in the range 0 <=
sortOrder < 2^31. A mailbox with a lower order should be
displayed before a mailbox with a higher order (that has the same
parent) in any mailbox listing in the client's UI. Mailboxes with
equal order SHOULD be sorted in alphabetical order by name. The
sorting should take into account locale-specific character order
convention.
Jenkins & Newman Expires September 9, 2019 [Page 9]
Internet-Draft JMAP Mail March 2019
o *totalEmails*: "UnsignedInt" (server-set) The number of emails in
this mailbox.
o *unreadEmails*: "UnsignedInt" (server-set) The number of emails in
this mailbox that have neither the "$seen" keyword nor the
"$draft" keyword.
o *totalThreads*: "UnsignedInt" (server-set) The number of threads
where at least one email in the thread is in this mailbox.
o *unreadThreads*: "UnsignedInt" (server-set) An indication of the
number of "unread" threads in the mailbox. For compatibility with
existing implementations, the way "unread threads" is determined
is not mandated in this document. The simplest solution to
implement is simply the number of threads where at least one email
in the thread is both in this mailbox and has neither the "$seen"
nor "$draft" keywords. However, a quality implementation will
return the number of unread items the user would see if they
opened that mailbox. A thread is shown as unread if it contains
any unread messages that will be displayed when the thread is
opened. Therefore "unreadThreads" should be the number of threads
where at least one email in the thread has neither the "$seen" nor
the "$draft" keyword AND at least one email in the thread is in
this mailbox. Note, the unread email does not need to be the one
in this mailbox. In addition, the Trash mailbox (that is a
mailbox whose "role" is "trash") is treated specially:
1. Emails that are *only* in the Trash (and no other mailbox) are
ignored when calculating the "unreadThreads" count of other
mailboxes.
2. Emails that are *not* in the Trash are ignored when
calculating the "unreadThreads" count for the Trash mailbox.
The result of this is that emails in the Trash are treated as
though they are in a separate thread for the purposes of unread
counts. It is expected that clients will hide emails in the Trash
when viewing a thread in another mailbox and vice versa. This
allows you to delete a single email to the Trash out of a thread.
So for example, suppose you have an account where the entire
contents is a single thread with 2 emails: an unread email in the
Trash and a read email in the Inbox. The "unreadThreads" count
would be "1" for the Trash and "0" for the Inbox.
o *myRights*: "MailboxRights" (server-set) The set of rights (ACLs)
the user has in relation to this mailbox. These are backwards
compatible with IMAP ACLs, as defined in [RFC4314]. A
_MailboxRights_ object has the following properties:
Jenkins & Newman Expires September 9, 2019 [Page 10]
Internet-Draft JMAP Mail March 2019
* *mayReadItems*: "Boolean" If true, the user may use this
mailbox as part of a filter in a _Email/query_ call and the
mailbox may be included in the _mailboxIds_ set of _Email_
objects. Email objects may be fetched if they are in *at least
one* mailbox with this permission. If a sub-mailbox is shared
but not the parent mailbox, this may be "false". Corresponds
to IMAP ACLs "lr" (if mapping from IMAP, both are required for
this to be "true").
* *mayAddItems*: "Boolean" The user may add mail to this mailbox
(by either creating a new email or moving an existing one).
Corresponds to IMAP ACL "i".
* *mayRemoveItems*: "Boolean" The user may remove mail from this
mailbox (by either changing the mailboxes of an email or
deleting it). Corresponds to IMAP ACLs "te" (if mapping from
IMAP, both are required for this to be "true").
* *maySetSeen*: "Boolean" The user may add or remove the "$seen"
keyword to/from an email. If an email belongs to multiple
mailboxes, the user may only modify "$seen" if they have this
permission for *all* of the mailboxes. Corresponds to IMAP ACL
"s".
* *maySetKeywords*: "Boolean" The user may add or remove any
keyword _other than_ "$seen" to/from an email. If an email
belongs to multiple mailboxes, the user may only modify
keywords if they have this permission for *all* of the
mailboxes. Corresponds to IMAP ACL "w".
* *mayCreateChild*: "Boolean" The user may create a mailbox with
this mailbox as its parent. Corresponds to IMAP ACL "k".
* *mayRename*: "Boolean" The user may rename the mailbox or make
it a child of another mailbox. Corresponds to IMAP ACL "x"
(although this covers both rename and delete permissions).
* *mayDelete*: "Boolean" The user may delete the mailbox itself.
Corresponds to IMAP ACL "x" (although this covers both rename
and delete permissions).
* *maySubmit*: "Boolean" Messages may be submitted directly to
this mailbox. Corresponds to IMAP ACL "p".
o *isSubscribed*: "Boolean" Has the user indicated they wish to see
this mailbox in their client? This SHOULD default to "false" for
mailboxes in shared accounts the user has access to, and "true"
for any new mailboxes created by the user themself. This MUST be
Jenkins & Newman Expires September 9, 2019 [Page 11]
Internet-Draft JMAP Mail March 2019
stored separately per-user where multiple users have access to a
shared mailbox. A user may have permission to access a large
number of shared accounts, or a shared account with a very large
set of mailboxes, but only be interested in the contents of a few
of these. Clients may choose only to display mailboxes to the
user that have the "isSubscribed" property set to "true", and
offer a separate UI to allow the user to see and subscribe/
unsubscribe from the full set of mailboxes. However, clients MAY
choose to ignore this property, either entirely for ease of
implementation, or just for an account where "isPersonal" is
"true" (indicating it is the user's own, rather than a shared
account). This property corresponds to IMAP ([RFC3501]) mailbox
subscriptions.
For IMAP compatibility, an email in both the Trash and another
mailbox SHOULD be treated by the client as existing in both places
(i.e. when emptying the trash, the client should just remove the
Trash mailbox and leave it in the other mailbox).
The following JMAP methods are supported:
2.1. Mailbox/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1. The _ids_ argument may be "null" to fetch all at once.
2.2. Mailbox/changes
Standard "/changes" method as described in [I-D.ietf-jmap-core]
section 5.2, but with one extra argument to the response:
o *updatedProperties*: "String[]|null" If only the mailbox counts
(unread/total emails/threads) have changed since the old state,
this will be the list of properties that may have changed, i.e.
"["totalEmails", "unreadEmails", "totalThreads",
"unreadThreads"]". If the server is unable to tell if only counts
have changed, it MUST just be "null".
Since counts frequently change but other properties are generally
only changed rarely, the server can help the client optimise data
transfer by keeping track of changes to email/thread counts
separately to other state changes. The _updatedProperties_ array may
be used directly via a back-reference in a subsequent Mailbox/get
call in the same single request so only these properties are returned
if nothing else has changed.
Jenkins & Newman Expires September 9, 2019 [Page 12]
Internet-Draft JMAP Mail March 2019
2.3. Mailbox/query
Standard "/query" method as described in [I-D.ietf-jmap-core] section
5.5, but with the following additional request argument:
o *sortAsTree*: "Boolean" (default: false) If "true", when sorting
the query results and comparing two mailboxes a and b:
* If a is an ancestor of b, it always comes first regardless of
the _sort_ comparators. Similarly, if a is descendant of b,
then b always comes first.
* Otherwise, if a and b do not share a _parentId_, find the
nearest ancestors of each that do have the same _parentId_ and
compare the sort properties on those mailboxes instead.
The result of this is that the mailboxes are sorted as a tree
according to the parentId properties, with each set of children
with a common parent sorted according to the standard sort
comparators.
o *filterAsTree*: "Boolean" (default: false) If "true", a mailbox is
only included in the query if all its ancestors are also included
in the query according to the filter.
A *FilterCondition* object has the following properties, any of which
may be omitted:
o *parentId*: "Id|null" The Mailbox _parentId_ property must match
the given value exactly.
o *name*: "String" The Mailbox _name_ property contains the given
string.
o *role*: "String|null" The Mailbox _role_ property must match the
given value exactly.
o *hasAnyRole*: "Boolean" If "true", a Mailbox matches if it has any
non-"null" value for its _role_ property.
o *isSubscribed*: "Boolean" The "isSubscribed" property of the
mailbox must be identical to the value given to match the
condition.
A Mailbox object matches the FilterCondition if and only if all of
the given conditions match. If zero properties are specified, it is
automatically "true" for all objects.
Jenkins & Newman Expires September 9, 2019 [Page 13]
Internet-Draft JMAP Mail March 2019
The following Mailbox properties MUST be supported for sorting:
o "sortOrder"
o "name"
2.4. Mailbox/queryChanges
Standard "/queryChanges" method as described in [I-D.ietf-jmap-core]
section 5.6.
2.5. Mailbox/set
Standard "/set" method as described in [I-D.ietf-jmap-core] section
5.3, but with the following additional request argument:
o *onDestroyRemoveMessages*: "Boolean" (default: false) If "false",
any attempt to destroy a mailbox that still has messages in it
will be rejected with a "mailboxHasEmail" SetError. If "true",
any messages that were in the mailbox will be removed from it, and
if in no other mailboxes will be destroyed when the mailbox is
destroyed.
The following extra _SetError_ types are defined:
For *destroy*:
o "mailboxHasChild": The mailbox still has at least one child
mailbox. The client MUST remove these before it can delete the
parent mailbox.
o "mailboxHasEmail": The mailbox has at least one message assigned
to it and the _onDestroyRemoveMessages_ argument was "false".
2.6. Example
Fetching all mailboxes in an account:
[[ "Mailbox/get", {
"accountId": "u33084183",
"ids": null
}, "0" ]]
And response:
Jenkins & Newman Expires September 9, 2019 [Page 14]
Internet-Draft JMAP Mail March 2019
[[ "Mailbox/get", {
"accountId": "u33084183",
"state": "78540",
"list": [{
"id": "MB23cfa8094c0f41e6",
"name": "Inbox",
"parentId": null,
"role": "inbox",
"sortOrder": 10,
"totalEmails": 16307,
"unreadEmails": 13905,
"totalThreads": 5833,
"unreadThreads": 5128,
"myRights": {
"mayAddItems": true,
"mayRename": false,
"maySubmit": true,
"mayDelete": false,
"maySetKeywords": true,
"mayRemoveItems": true,
"mayCreateChild": true,
"maySetSeen": true,
"mayReadItems": true
},
"isSubscribed": true
}, {
"id": "MB674cc24095db49ce",
"name": "Important mail",
...
}, ... ],
"notFound": []
}, "0" ]]
Now suppose a message is marked read and we get a push update that
the Mailbox state has changed. You might fetch the updates like
this:
Jenkins & Newman Expires September 9, 2019 [Page 15]
Internet-Draft JMAP Mail March 2019
[[ "Mailbox/changes", {
"accountId": "u33084183",
"sinceState": "78540"
}, "0" ],
[ "Mailbox/get", {
"accountId": "u33084183",
"#ids": {
"resultOf": "0",
"name": "Mailbox/changes",
"path": "/created"
}
}, "1" ],
[ "Mailbox/get", {
"accountId": "u33084183",
"#ids": {
"resultOf": "0",
"name": "Mailbox/changes",
"path": "/updated"
},
"#properties": {
"resultOf": "0",
"name": "Mailbox/changes",
"path": "/updatedProperties"
}
}, "2" ]]
This fetches the list of ids for created/updated/destroyed mailboxes,
then using back-references fetches the data for just the created/
updated mailboxes in the same request. The response may look
something like this:
Jenkins & Newman Expires September 9, 2019 [Page 16]
Internet-Draft JMAP Mail March 2019
[[ "Mailbox/changes", {
"accountId": "u33084183",
"oldState": "78541",
"newState": "78542",
"hasMoreChanges": false,
"updatedProperties": [
"totalEmails", "unreadEmails",
"totalThreads", "unreadThreads"
],
"created": [],
"updated": ["MB23cfa8094c0f41e6"],
"destroyed": []
}, "0" ],
[ "Mailbox/get", {
"accountId": "u33084183",
"state": "78542",
"list": [],
"notFound": []
}, "1" ],
[ "Mailbox/get", {
"accountId": "u33084183",
"state": "78542",
"list": [{
"id": "MB23cfa8094c0f41e6",
"totalEmails": 16307,
"unreadEmails": 13903,
"totalThreads": 5833,
"unreadThreads": 5127
}],
"notFound": []
}, "2" ]]
Here's an example where we try to rename one mailbox and destroy
another:
[[ "Mailbox/set", {
"accountId": "u33084183",
"ifInState": "78542",
"update": {
"MB674cc24095db49ce": {
"name": "Maybe important mail"
}
},
"destroy": [ "MB23cfa8094c0f41e6" ]
}, "0" ]]
Suppose the rename succeeds, but we don't have permission to destroy
the mailbox we tried to destroy, we might get back:
Jenkins & Newman Expires September 9, 2019 [Page 17]
Internet-Draft JMAP Mail March 2019
[[ "Mailbox/set", {
"accountId": "u33084183",
"oldState": "78542",
"newState": "78549",
"updated": {
"MB674cc24095db49ce": null
},
"notDestroyed": {
"MB23cfa8094c0f41e6": {
"type": "forbidden"
}
}
}, "0" ]]
3. Threads
Replies are grouped together with the original message to form a
thread. In JMAP, a thread is simply a flat list of emails, ordered
by date. Every email MUST belong to a thread, even if it is the only
email in the thread.
The exact algorithm for determining whether two emails belong to the
same thread is not mandated in this spec to allow for compatibility
with different existing systems. For new implementations, it is
suggested that two messages belong in the same thread if both of the
following conditions apply:
1. An identical RFC5322 message id appears in both messages in any
of the Message-Id, In-Reply-To and References headers.
2. After stripping automatically added prefixes such as "Fwd:",
"Re:", "[List-Tag]" etc. and ignoring whitespace, the subjects
are the same. This avoids the situation where a person replies
to an old message as a convenient way of finding the right
recipient to send to, but changes the subject and starts a new
conversation.
If emails are delivered out of order for some reason, a user may
receive two emails in the same thread but without headers that
associate them with each other. The arrival of a third email in the
thread may provide the missing references to join them all together
into a single thread. Since the _threadId_ of an email is immutable,
if the server wishes to merge the threads, it MUST handle this by
deleting and reinserting (with a new email id) the emails that change
threadId.
A *Thread* object has the following properties:
Jenkins & Newman Expires September 9, 2019 [Page 18]
Internet-Draft JMAP Mail March 2019
o *id*: "Id" (immutable; server-set) The id of the thread.
o *emailIds*: "Id[]" (server-set) The ids of the emails in the
thread, sorted by the _receivedAt_ date of the email, oldest
first. If two emails have an identical date, the sort is server-
dependent but MUST be stable (sorting by id is recommended).
The following JMAP methods are supported:
3.1. Thread/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1.
3.1.1. Example
Request:
[[ "Thread/get", {
"accountId": "acme",
"ids": ["f123u4", "f41u44"]
}, "#1" ]]
with response:
[[ "Thread/get", {
"accountId": "acme",
"state": "f6a7e214",
"list": [
{
"id": "f123u4",
"emailIds": [ "eaa623", "f782cbb"]
},
{
"id": "f41u44",
"emailIds": [ "82cf7bb" ]
}
],
"notFound": []
}, "#1" ]]
3.2. Thread/changes
Standard "/changes" method as described in [I-D.ietf-jmap-core]
section 5.2.
Jenkins & Newman Expires September 9, 2019 [Page 19]
Internet-Draft JMAP Mail March 2019
4. Emails
The *Email* object is a representation of an [RFC5322] message, which
allows clients to avoid the complexities of MIME parsing, transfer
encoding and character encoding.
4.1. Properties of the Email object
Broadly, a message consists of two parts: a list of header fields,
then a body. The JMAP Email object provides a way to access the full
structure, or to use simplified properties and avoid some complexity
if this is sufficient for the client application.
While raw headers can be fetched and set, the vast majority of
clients should use an appropriate parsed form for each of the headers
it wants to process, as this allows it to avoid the complexities of
various encodings that are required in a valid RFC5322 message.
The body of a message is normally a MIME-encoded set of documents in
a tree structure. This may be arbitrarily nested, but the majority
of email clients present a flat model of an email body (normally
plain text or HTML), with a set of attachments. Flattening the MIME
structure to form this model can be difficult, and causes
inconsistency between clients. Therefore in addition to the
_bodyStructure_ property, which gives the full tree, the Email object
contains 3 alternate properties with flat lists of body parts:
o _textBody_/_htmlBody_: These provide a list of parts that should
be rendered sequentially as the "body" of the message. This is a
list rather than a single part as messages may have headers and/or
footers appended/prepended as separate parts as they are
transmitted, and some clients send text and images intended to be
displayed inline in the body (or even videos and sound clips) as
multiple parts rather than a single HTML part with referenced
images.
Because MIME allows for multiple representations of the same data
(using "multipart/alternative"), there is a textBody property (which
prefers a plain text representation) and an htmlBody property (which
prefers an HTML representation) to accommodate the two most common
client requirements. The same part may appear in both lists where
there is no alternative between the two.
o _attachments_: This provides a list of parts that should be
presented as "attachments" to the message. Some images may be
solely there for embedding within an HTML body part; clients may
wish to not present these as attachments in the user interface if
they are displaying the HTML with the embedded images directly.
Jenkins & Newman Expires September 9, 2019 [Page 20]
Internet-Draft JMAP Mail March 2019
Some parts may also be in htmlBody/textBody; again, clients may
wish to not present these as attachments in the user interface if
rendered as part of the body.
The _bodyValues_ property allows for clients to fetch the value of
text parts directly without having to do a second request for the
blob, and have the server handle decoding the charset into unicode.
This data is in a separate property rather than on the EmailBodyPart
object to avoid duplication of large amounts of data, as the same
part may be included twice if the client fetches more than one of
bodyStructure, textBody and htmlBody.
In the following subsections the common notational convention for
wildcards has been adopted for content types, so "foo/*" means any
content type that starts with "foo/".
Due to the number of properties involved, the set of _Email_
properties is specified over the following four sub-sections. This
is purely for readability; all properties are top-level peers.
4.1.1. Metadata
These properties represent metadata about the [RFC5322] message, and
are not derived from parsing the message itself.
o *id*: "Id" (immutable; server-set) The id of the Email object.
Note, this is the JMAP object id, NOT the [RFC5322] Message-ID
header field value.
o *blobId*: "Id" (immutable; server-set) The id representing the raw
octets of the [RFC5322] message. This may be used to download the
raw original message, or to attach it directly to another Email
etc.
o *threadId*: "Id" (immutable; server-set) The id of the Thread to
which this Email belongs.
o *mailboxIds*: "Id[Boolean]" The set of Mailbox ids this email
belongs to. An email in the mail store MUST belong to one or more
mailboxes at all times (until it is deleted). The set is
represented as an object, with each key being a _Mailbox id_. The
value for each key in the object MUST be "true".
o *keywords*: "String[Boolean]" (default: {}) A set of keywords that
apply to the email. The set is represented as an object, with the
keys being the _keywords_. The value for each key in the object
MUST be "true". Keywords are shared with IMAP. The six system
keywords from IMAP are treated specially. The following four
Jenkins & Newman Expires September 9, 2019 [Page 21]
Internet-Draft JMAP Mail March 2019
keywords have their first character changed from "\" in IMAP to
"$" in JMAP and have particular semantic meaning:
* "$draft": The email is a draft the user is composing.
* "$seen": The email has been read.
* "$flagged": The email has been flagged for urgent/special
attention.
* "$answered": The email has been replied to.
The IMAP "\Recent" keyword is not exposed via JMAP. The IMAP
"\Deleted" keyword is also not present: IMAP uses a delete+expunge
model, which JMAP does not. Any message with the "\Deleted"
keyword MUST NOT be visible via JMAP (including as part of any
mailbox counts). Users may add arbitrary keywords to an email.
For compatibility with IMAP, a keyword is a case-insensitive
string of 1-255 characters in the ASCII subset %x21-%x7e (excludes
control chars and space), and MUST NOT include any of these
characters: "( ) { ] % * " \" Because JSON is case-sensitive,
servers MUST return keywords in lower-case. The IANA Keyword
Registry [2] as established in [RFC5788] assigns semantic meaning
to some other keywords in common use. New keywords may be
established here in the future. In particular, note:
* "$forwarded": The email has been forwarded.
* "$phishing": The email is highly likely to be phishing.
Clients SHOULD warn users to take care when viewing this email
and disable links and attachments.
* "$junk": The email is definitely spam. Clients SHOULD set this
flag when users report spam to help train automated spam-
detection systems.
* "$notjunk": The email is definitely not spam. Clients SHOULD
set this flag when users indicate an email is legitimate, to
help train automated spam-detection systems.
o *size*: "UnsignedInt" (immutable; server-set) The size, in octets,
of the raw data for the [RFC5322] message (as referenced by the
_blobId_, i.e. the number of octets in the file the user would
download).
o *receivedAt*: "UTCDate" (immutable; default: time of creation on
server) The date the email was received by the message store.
This is the _internal date_ in IMAP ([RFC3501]).
Jenkins & Newman Expires September 9, 2019 [Page 22]
Internet-Draft JMAP Mail March 2019
4.1.2. Header fields parsed forms
Header field properties are derived from the [RFC5322] and [RFC6532]
message header fields. All header fields may be fetched in a raw
form. Some headers may also be fetched in a parsed form. The
structured form that may be fetched depends on the header. The
following forms are defined:
4.1.2.1. Raw
Type: "String"
The raw octets of the header field value from the first octet
following the header field name terminating colon, up to but
excluding the header field terminating CRLF. Any standards-compliant
message MUST be either ASCII (RFC5322) or UTF-8 (RFC6532), however
other encodings exist in the wild. A server SHOULD replace any octet
or octet run with the high bit set that violates UTF-8 syntax with
the unicode replacement character (U+FFFD). Any NUL octet MUST be
dropped.
This form will typically have a leading space, as most generated
messages insert a space after the colon that terminates the header
field name.
4.1.2.2. Text
Type: "String"
The header field value with:
1. White space unfolded (as defined in [RFC5322] section 2.2.3).
2. The terminating CRLF at the end of the value removed.
3. Any SP characters at the beginning of the value removed.
4. Any syntactically correct [RFC2047] encoded sections with a known
character set decoded. Any [RFC2047] encoded NUL octets or
control characters are dropped from the decoded value. Any text
that looks like [RFC2047] syntax but violates [RFC2047] placement
or whitespace rules MUST NOT be decoded.
5. The resulting unicode converted to NFC form.
If any decodings fail, the parser SHOULD insert a unicode replacement
character (U+FFFD) and attempt to continue as much as possible.
Jenkins & Newman Expires September 9, 2019 [Page 23]
Internet-Draft JMAP Mail March 2019
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
following header fields:
o Subject
o Comments
o Keywords
o List-Id
o Any header not defined in [RFC5322] or [RFC2369]
4.1.2.3. Addresses
Type: "EmailAddress[]"
The header is parsed as an "address-list" value, as specified in
[RFC5322] section 3.4, into the "EmailAddress[]" type. There is an
EmailAddress item for each "mailbox" parsed from the "address-list".
Group and comment information is discarded.
The *EmailAddress* object has the following properties:
o *name*: "String|null" The _display-name_ of the [RFC5322]
_mailbox_. If this is a _quoted-string_:
1. The surrounding DQUOTE characters are removed.
2. Any _quoted-pair_ is decoded.
3. White-space is unfolded, and then any leading and trailing
white-space is removed.
If there is no _display-name_ but there is a _comment_ immediately
following the _addr-spec_, the value of this SHOULD be used
instead. Otherwise, this property is "null".
o *email*: "String" The _addr-spec_ of the [RFC5322] _mailbox_.
Any syntactically correct [RFC2047] encoded sections with a known
encoding MUST be decoded, following the same rules as for the _Text_
form.
Parsing SHOULD be best-effort in the face of invalid structure to
accommodate invalid messages and semi-complete drafts. EmailAddress
Jenkins & Newman Expires September 9, 2019 [Page 24]
Internet-Draft JMAP Mail March 2019
objects MAY have an _email_ property that does not conform to the
_addr-spec_ form (for example, may not contain an @ symbol).
For example, the following "address-list" string:
" James Smythe" <james@example.com>, Friends:
jane@example.com, =?UTF-8?Q?John_Sm=C3=AEth?=
<john@example.com>;
would be parsed as:
[
{ "name": "James Smythe", "email": "james@example.com" },
{ "name": null, "email": "jane@example.com" },
{ "name": "John Smith", "email": "john@example.com" }
]
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
following header fields:
o From
o Sender
o Reply-To
o To
o Cc
o Bcc
o Resent-From
o Resent-Sender
o Resent-Reply-To
o Resent-To
o Resent-Cc
o Resent-Bcc
o Any header not defined in [RFC5322] or [RFC2369]
Jenkins & Newman Expires September 9, 2019 [Page 25]
Internet-Draft JMAP Mail March 2019
4.1.2.4. GroupedAddresses
Type: "EmailAddressGroup[]"
This is similar to the Addresses form but preserves group
information. The header is parsed as an "address-list" value, as
specified in [RFC5322] section 3.4, into the "GroupedAddresses[]"
type. Consecutive mailboxes that are not part of a group are still
collected under an EmailAddressGroup object to provide a uniform
type.
The *EmailAddressGroup* object has the following properties:
o *name*: "String|null" The _display-name_ of the [RFC5322] _group_,
or "null" if the addresses are not part of a group. If this is a
_quoted-string_ it is processed the same as the _name_ in the
_EmailAddress_ type.
o *addresses*: "EmailAddress[]" The _mailbox_es that belong to this
group, represented as EmailAddress objects.
Any syntactically correct [RFC2047] encoded sections with a known
encoding MUST be decoded, following the same rules as for the _Text_
form.
Parsing SHOULD be best-effort in the face of invalid structure to
accommodate invalid messages and semi-complete drafts.
For example, the following "address-list" string:
" James Smythe" <james@example.com>, Friends:
jane@example.com, =?UTF-8?Q?John_Sm=C3=AEth?=
<john@example.com>;
would be parsed as:
[
{ "name": null, "addresses": [
{ "name": "James Smythe", "email": "james@example.com" }
]},
{ "name": "Friends", "addresses": [
{ "name": null, "email": "jane@example.com" },
{ "name": "John Smith", "email": "john@example.com" }
]}
]
Jenkins & Newman Expires September 9, 2019 [Page 26]
Internet-Draft JMAP Mail March 2019
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
same header fields as the _Addresses_ form.
4.1.2.5. MessageIds
Type: "String[]|null"
The header is parsed as a list of "msg-id" values, as specified in
[RFC5322] section 3.6.4, into the "String[]" type. CFWS and
surrounding angle brackets ("<>") are removed. If parsing fails, the
value is "null".
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
following header fields:
o Message-ID
o In-Reply-To
o References
o Resent-Message-ID
o Any header not defined in [RFC5322] or [RFC2369]
4.1.2.6. Date
Type: "Date|null"
The header is parsed as a "date-time" value, as specified in
[RFC5322] section 3.3, into the "Date" type. If parsing fails, the
value is "null".
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
following header fields:
o Date
o Resent-Date
o Any header not defined in [RFC5322] or [RFC2369]
Jenkins & Newman Expires September 9, 2019 [Page 27]
Internet-Draft JMAP Mail March 2019
4.1.2.7. URLs
Type: "String[]|null"
The header is parsed as a list of URLs, as described in [RFC2369],
into the "String[]" type. Values do not include the surrounding
angle brackets or any comments in the header with the URLs. If
parsing fails, the value is "null".
To prevent obviously nonsense behaviour, which can lead to
interoperability issues, this form may only be fetched or set for the
following header fields:
o List-Help
o List-Unsubscribe
o List-Subscribe
o List-Post
o List-Owner
o List-Archive
o Any header not defined in [RFC5322] or [RFC2369]
4.1.3. Header fields properties
The following low-level *Email* property is specified for complete
access to the header data of the message:
o *headers*: "EmailHeader[]" (immutable) This is a list of all
[RFC5322] header fields, in the same order they appear in the
message. An *EmailHeader* object has the following properties:
* *name*: "String" The header _field name_ as defined in
[RFC5322], with the same capitalization that it has in the
message.
* *value*: "String" The header _field value_ as defined in
[RFC5322], in _Raw_ form.
In addition, the client may request/send properties representing
individual header fields of the form:
header:{header-field-name}
Jenkins & Newman Expires September 9, 2019 [Page 28]
Internet-Draft JMAP Mail March 2019
Where "{header-field-name}" means any series of one or more printable
ASCII characters (i.e. characters that have values between 33 and
126, inclusive), except colon. The property may also have the
following suffixes:
o *:as{header-form}* This means the value is in a parsed form, where
"{header-form}" is one of the parsed-form names specified above.
If not given, the value is in _Raw_ form.
o *:all* This means the value is an array, with the items
corresponding to each instance of the header field, in the order
they appear in the message. If this suffix is not used, the
result is the value of the *last* instance of the header field
(i.e. identical to the *last* item in the array if :all is used),
or "null" if none.
If both suffixes are used, they MUST be specified in the order above.
Header field names are matched case-insensitively. The value is
typed according to the requested form, or an array of that type if
:all is used. If no header fields exist in the message with the
requested name, the value is "null" if fetching a single instance, or
the empty array if requesting :all.
As a simple example, if the client requests a property called
"header:subject", this means find the _last_ header field in the
message named "subject" (matched case-insensitively) and return the
value in _Raw_ form, or "null" if no header of this name is found.
For a more complex example, consider the client requesting a property
called "header:Resent-To:asAddresses:all". This means:
1. Find _all_ header fields named Resent-To (matched case-
insensitively).
2. For each instance parse the header field value in the _Addresses_
form.
3. The result is of type "EmailAddress[][]" - each item in the array
corresponds to the parsed value (which is itself an array) of the
Resent-To header field instance.
The following convenience properties are also specified for the
*Email* object:
o *messageId*: "String[]|null" (immutable) The value is identical to
the value of _header:Message-ID:asMessageIds_. For messages
conforming to RFC5322 this will be an array with a single entry.
Jenkins & Newman Expires September 9, 2019 [Page 29]
Internet-Draft JMAP Mail March 2019
o *inReplyTo*: "String[]|null" (immutable) The value is identical to
the value of _header:In-Reply-To:asMessageIds_.
o *references*: "String[]|null" (immutable) The value is identical
to the value of _header:References:asMessageIds_.
o *sender*: "EmailAddress[]|null" (immutable) The value is identical
to the value of _header:Sender:asAddresses_.
o *from*: "EmailAddress[]|null" (immutable) The value is identical
to the value of _header:From:asAddresses_.
o *to*: "EmailAddress[]|null" (immutable) The value is identical to
the value of _header:To:asAddresses_.
o *cc*: "EmailAddress[]|null" (immutable) The value is identical to
the value of _header:Cc:asAddresses_.
o *bcc*: "EmailAddress[]|null" (immutable) The value is identical to
the value of _header:Bcc:asAddresses_.
o *replyTo*: "EmailAddress[]|null" (immutable) The value is
identical to the value of _header:Reply-To:asAddresses_.
o *subject*: "String|null" (immutable) The value is identical to the
value of _header:Subject:asText_.
o *sentAt*: "Date|null" (immutable; default on creation: current
server time) The value is identical to the value of
_header:Date:asDate_.
4.1.4. Body parts
These properties are derived from the [RFC5322] message body and its
[RFC2045] MIME entities.
A *EmailBodyPart* object has the following properties:
o *partId*: "String|null" Identifies this part uniquely within the
Email. This is scoped to the _emailId_ and has no meaning outside
of the JMAP Email object representation. This is "null" if, and
only if, the part is of type "multipart/*".
o *blobId*: "Id|null" The id representing the raw octets of the
contents of the part, after decoding any known _Content-Transfer-
Encoding_ (as defined in [RFC2045]), or "null" if, and only if,
the part is of type "multipart/*". Note, two parts may be
transfer-encoded differently but have the same blob id if their
Jenkins & Newman Expires September 9, 2019 [Page 30]
Internet-Draft JMAP Mail March 2019
decoded octets are identical and the server is using a secure hash
of the data for the blob id. If the transfer encoding is unknown,
it is treated as though it had no transfer-encoding.
o *size*: "UnsignedInt" The size, in octets, of the raw data after
content transfer decoding (as referenced by the _blobId_, i.e. the
number of octets in the file the user would download).
o *headers*: "EmailHeader[]" This is a list of all header fields in
the part, in the order they appear in the message. The values are
in _Raw_ form.
o *name*: "String|null" This is the [RFC2231] decoded _filename_
parameter of the _Content-Disposition_ header field, or (for
compatibility with existing systems) if not present then the
[RFC2047] decoded _name_ parameter of the _Content-Type_ header
field.
o *type*: "String" The value of the _Content-Type_ header field of
the part, if present, otherwise the implicit type as per the MIME
standard ("text/plain", or "message/rfc822" if inside a
"multipart/digest"). CFWS is removed and any parameters are
stripped.
o *charset*: "String|null" The value of the charset parameter of the
_Content-Type_ header field, if present, or "null" if the header
field is present but not of type "text/*". If there is no
_Content-Type_ header field, or it exists and is of type "text/*"
but has no charset parameter, this is the implicit charset as per
the MIME standard: "us-ascii".
o *disposition*: "String|null" The value of the _Content-
Disposition_ header field of the part, if present, otherwise
"null". CFWS is removed and any parameters are stripped.
o *cid*: "String|null" The value of the _Content-Id_ header field of
the part, if present, otherwise "null". CFWS and surrounding
angle brackets ("<>") are removed. This may be used to reference
the content from within an [HTML] body part using the "cid:"
protocol, as defined in [RFC2392].
o *language*: "String[]|null" The list of language tags, as defined
in [RFC3282], in the _Content-Language_ header field of the part,
if present.
o *location*: "String|null" The URI, as defined in [RFC2557], in the
_Content-Location_ header field of the part, if present.
Jenkins & Newman Expires September 9, 2019 [Page 31]
Internet-Draft JMAP Mail March 2019
o *subParts*: "EmailBodyPart[]|null" If type is "multipart/*", this
contains the body parts of each child.
In addition, the client may request/send EmailBodyPart properties
representing individual header fields, following the same syntax and
semantics as for the Email object, e.g. "header:Content-Type".
The following *Email* properties are specified for access to the body
data of the message:
o *bodyStructure*: "EmailBodyPart" (immutable) This is the full MIME
structure of the message body, represented as an array of the
message's top-level MIME parts, without recursing into "message/
rfc822" or "message/global" parts. Note that EmailBodyParts may
have subParts if they are of type "multipart/*".
o *bodyValues*: "String[EmailBodyValue]" (immutable) This is a map
of _partId_ to an *EmailBodyValue* object for none, some or all
"text/*" parts. Which parts are included and whether the value is
truncated is determined by various arguments to _Email/get_ and
_Email/parse_. An *EmailBodyValue* object has the following
properties:
* *value*: "String" The value of the body part after decoding
_Content-Transfer-Encoding_ and decoding the _Content-Type_
charset, if both known to the server, and with any CRLF
replaced with a single LF. The server MAY use heuristics to
determine the charset to use for decoding if the charset is
unknown, or if no charset is given, or if it believes the
charset given is incorrect. Decoding is best-effort and SHOULD
insert the unicode replacement character (U+FFFD) and continue
when a malformed section is encountered. Note that due to the
charset decoding and line ending normalisation, the length of
this string will probably not be exactly the same as the _size_
property on the corresponding EmailBodyPart.
* *isEncodingProblem*: "Boolean" (default: false) This is "true"
if malformed sections were found while decoding the charset, or
the charset was unknown, or the content-transfer-encoding was
unknown.
* *isTruncated*: "Boolean" (default: false) This is "true" if the
_value_ has been truncated.
See the security considerations section for issues related to
truncation and heuristic determination of content-type and
charset.
Jenkins & Newman Expires September 9, 2019 [Page 32]
Internet-Draft JMAP Mail March 2019
o *textBody*: "EmailBodyPart[]" (immutable) A list of "text/plain",
"text/html", "image/*", "audio/*" and/or "video/*" parts to
display (sequentially) as the message body, with a preference for
"text/plain" when alternative versions are available.
o *htmlBody*: "EmailBodyPart[]" (immutable) A list of "text/plain",
"text/html", "image/*", "audio/*" and/or "video/*" parts to
display (sequentially) as the message body, with a preference for
"text/html" when alternative versions are available.
o *attachments*: "EmailBodyPart[]" (immutable) A list of all parts
in _bodyStructure_, traversing depth-first, which satisfy either
of the following conditions:
* not of type "multipart/*" and not included in _textBody_ or
_htmlBody_
* of type "image/*", "audio/*" or "video/*" and not in both
_textBody_ and _htmlBody_
None of these parts include subParts, including "message/*" types.
Attached messages may be fetched using the Email/parse method and
the blobId. Note, an [HTML] body part may reference image parts
in attachments using "cid:" links to reference the _Content-Id_,
as defined in [RFC2392], or by referencing the _Content-Location_.
o *hasAttachment*: "Boolean" (immutable; server-set) This is "true"
if there are one or more parts in the message that a client UI
should offer as downloadable. A server SHOULD set hasAttachment
to "true" if the _attachments_ list contains at least one item
that does not have "Content-Disposition: inline". The server MAY
ignore parts in this list that are processed automatically in some
way, or are referenced as embedded images in one of the "text/
html" parts of the message. The server MAY set hasAttachment
based on implementation-defined or site configurable heuristics.
o *preview*: "String" (immutable; server-set) A plain text fragment
of the message body. This is intended to be shown as a preview
line on a mailbox listing, and may be truncated when shown. The
server may choose which part of the message to include in the
preview; skipping quoted sections and salutations and collapsing
white-space can result in a more useful preview. This MUST NOT be
more than 256 characters in length. As this is derived from the
message content by the server, and the algorithm for doing so
could change over time, fetching this for an email a second time
MAY return a different result. However, the previous value is not
considered incorrect, and the change SHOULD NOT cause the Email
object to be considered as changed by the server.
Jenkins & Newman Expires September 9, 2019 [Page 33]
Internet-Draft JMAP Mail March 2019
The exact algorithm for decomposing bodyStructure into textBody,
htmlBody and attachments part lists is not mandated, as this is a
quality-of-service implementation issue and likely to require
workarounds for malformed content discovered over time. However, the
following algorithm (expressed here in JavaScript) is suggested as a
starting point, based on real-world experience:
function isInlineMediaType ( type ) {
return type.startsWith( 'image/' ) ||
type.startsWith( 'audio/' ) ||
type.startsWith( 'video/' );
}
function parseStructure ( parts, multipartType, inAlternative,
htmlBody, textBody, attachments ) {
// For multipartType == alternative
let textLength = textBody ? textBody.length : -1;
let htmlLength = htmlBody ? htmlBody.length : -1;
for ( let i = 0; i < parts.length; i += 1 ) {
let part = parts[i];
let isMultipart = part.type.startsWith( 'multipart/' );
// Is this a body part rather than an attachment
let isInline = part.disposition != "attachment" &&
// Must be one of the allowed body types
( part.type == "text/plain" ||
part.type == "text/html" ||
isInlineMediaType( part.type ) ) &&
// If multipart/related, only the first part can be inline
// If a text part with a filename, and not the first item
// in the multipart, assume it is an attachment
( i === 0 ||
( multipartType != "related" &&
( isInlineMediaType( part.type ) || !part.name ) ) );
if ( isMultipart ) {
let subMultiType = part.type.split( '/' )[1];
parseStructure( part.subParts, subMultiType,
inAlternative || ( subMultiType == 'alternative' ),
htmlBody, textBody, attachments );
} else if ( isInline ) {
if ( multipartType == 'alternative' ) {
switch ( part.type ) {
case 'text/plain':
textBody.push( part );
break;
case 'text/html':
Jenkins & Newman Expires September 9, 2019 [Page 34]
Internet-Draft JMAP Mail March 2019
htmlBody.push( part );
break;
default:
attachments.push( part );
break;
}
continue;
} else if ( inAlternative ) {
if ( part.type == 'text/plain' ) {
htmlBody = null;
}
if ( part.type == 'text/html' ) {
textBody = null;
}
}
if ( textBody ) {
textBody.push( part );
}
if ( htmlBody ) {
htmlBody.push( part );
}
if ( ( !textBody || !htmlBody ) &&
isInlineMediaType( part.type ) ) {
attachments.push( part );
}
} else {
attachments.push( part );
}
}
if ( multipartType == 'alternative' && textBody && htmlBody ) {
// Found HTML part only
if ( textLength == textBody.length &&
htmlLength != htmlBody.length ) {
for ( let i = htmlLength; i < htmlBody.length; i += 1 ) {
textBody.push( htmlBody[i] );
}
}
// Found plain text part only
if ( htmlLength == htmlBody.length &&
textLength != textBody.length ) {
for ( let i = textLength; i < textBody.length; i += 1 ) {
htmlBody.push( textBody[i] );
}
}
}
}
Jenkins & Newman Expires September 9, 2019 [Page 35]
Internet-Draft JMAP Mail March 2019
// Usage:
let htmlBody = [];
let textBody = [];
let attachments = [];
parseStructure( [ bodyStructure ], 'mixed', false,
htmlBody, textBody, attachments );
For instance, consider a message with both text and HTML versions
that's then gone through a list software manager that attaches a
header/footer. It might have a MIME structure something like:
multipart/mixed
text/plain, content-disposition=inline - A
multipart/mixed
multipart/alternative
multipart/mixed
text/plain, content-disposition=inline - B
image/jpeg, content-disposition=inline - C
text/plain, content-disposition=inline - D
multipart/related
text/html - E
image/jpeg - F
image/jpeg, content-disposition=attachment - G
application/x-excel - H
message/rfc822 - J
text/plain, content-disposition=inline - K
In this case, the above algorithm would decompose this to:
textBody => [ A, B, C, D, K ]
htmlBody => [ A, E, K ]
attachments => [ C, F, G, H, J ]
4.2. Email/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1, with the following additional request arguments:
o *bodyProperties*: "String[]" A list of properties to fetch for
each EmailBodyPart returned. If omitted, this defaults to:
[ "partId", "blobId", "size", "name", "type", "charset",
"disposition", "cid", "language", "location" ]
o *fetchTextBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the "textBody"
property.
Jenkins & Newman Expires September 9, 2019 [Page 36]
Internet-Draft JMAP Mail March 2019
o *fetchHTMLBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the "htmlBody"
property.
o *fetchAllBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the
"bodyStructure" property.
o *maxBodyValueBytes*: "UnsignedInt" (default: 0) If greater than
zero, the _value_ property of any EmailBodyValue object returned
in _bodyValues_ MUST be truncated if necessary so it does not
exceed this number of octets in size. If "0" (the default), no
truncation occurs. The server MUST ensure the truncation results
in valid UTF-8 and does not occur mid-codepoint. If the part is
of type "text/html", the server SHOULD NOT truncate inside an HTML
tag, e.g. in the middle of "<a href="https://example.com">".
There is no requirement for the truncated form to be a balanced
tree or valid HTML (indeed, the original source may well be
neither of these things).
If the standard _properties_ argument is omitted or "null", the
following default MUST be used instead of "all" properties:
[ "id", "blobId", "threadId", "mailboxIds", "keywords", "size",
"receivedAt", "messageId", "inReplyTo", "references", "sender", "from",
"to", "cc", "bcc", "replyTo", "subject", "sentAt", "hasAttachment",
"preview", "bodyValues", "textBody", "htmlBody", "attachments" ]
The following properties are expected to be fast to fetch in a
quality implementation:
o id
o blobId
o threadId
o mailboxIds
o keywords
o size
o receivedAt
o messageId
o inReplyTo
Jenkins & Newman Expires September 9, 2019 [Page 37]
Internet-Draft JMAP Mail March 2019
o sender
o from
o to
o cc
o bcc
o replyTo
o subject
o sentAt
o hasAttachment
o preview
Clients SHOULD take care when fetching any other properties, as there
may be significantly longer latency in fetching and returning the
data.
As specified above, parsed forms of headers may only be used on
appropriate header fields. Attempting to fetch a form that is
forbidden (e.g. "header:From:asDate") MUST result in the method call
being rejected with an "invalidArguments" error.
Where a specific header is requested as a property, the
capitalization of the property name in the response MUST be identical
to that used in the request.
4.2.1. Example
Request:
[[ "Email/get", {
"ids": [ "f123u456", "f123u457" ],
"properties": [ "threadId", "mailboxIds", "from", "subject",
"receivedAt", "header:List-POST:asURLs",
"htmlBody", "bodyValues" ],
"bodyProperties": [ "partId", "blobId", "size", "type" ],
"fetchHTMLBodyValues": true,
"maxBodyValueBytes": 256
}, "#1" ]]
and response:
Jenkins & Newman Expires September 9, 2019 [Page 38]
Internet-Draft JMAP Mail March 2019
[[ "Email/get", {
"accountId": "abc",
"state": "41234123231",
"list": [
{
"id": "f123u457",
"threadId": "ef1314a",
"mailboxIds": { "f123": true },
"from": [{ "name": "Joe Bloggs", "email": "joe@example.com" }],
"subject": "Dinner on Thursday?",
"receivedAt": "2013-10-13T14:12:00Z",
"header:List-POST:asURLs": [
"mailto:partytime@lists.example.com"
],
"htmlBody": [{
"partId": "1",
"blobId": "B841623871",
"size": 283331,
"type": "text/html"
}, {
"partId": "2",
"blobId": "B319437193",
"size": 10343,
"type": "text/plain"
}],
"bodyValues": {
"1": {
"isEncodingProblem": false,
"isTruncated": true,
"value": "<html><body><p>Hello ..."
},
"2": {
"isEncodingProblem": false,
"isTruncated": false,
"value": "-- Sent by your friendly mailing list ..."
}
}
}
],
"notFound": [ "f123u456" ]
}, "#1" ]]
4.3. Email/changes
Standard "/changes" method as described in [I-D.ietf-jmap-core]
section 5.2. If generating intermediate states for a large set of
changes, it is recommended that newer changes are returned first, as
these are generally of more interest to users.
Jenkins & Newman Expires September 9, 2019 [Page 39]
Internet-Draft JMAP Mail March 2019
4.4. Email/query
Standard "/query" method as described in [I-D.ietf-jmap-core] section
5.5, but with the following additional request arguments:
o *collapseThreads*: "Boolean" (default: false) If "true", emails in
the same thread as a previous email in the list (given the filter
and sort order) will be removed from the list. This means only
one email at most will be included in the list for any given
thread.
In quality implementations, the query "total" property is expected to
be fast to calculate when the filter consists solely of a single
"inMailbox" property, as it is the same as the totalEmails or
totalThreads properties (depending on whether collapseThreads is
true) of the associated Mailbox object.
4.4.1. Filtering
A *FilterCondition* object has the following properties, any of which
may be omitted:
o *inMailbox*: "Id" A mailbox id. An email must be in this mailbox
to match the condition.
o *inMailboxOtherThan*: "Id[]" A list of mailbox ids. An email must
be in at least one mailbox not in this list to match the
condition. This is to allow messages solely in trash/spam to be
easily excluded from a search.
o *before*: "UTCDate" The _receivedAt_ date-time of the email must
be before this date-time to match the condition.
o *after*: "UTCDate" The _receivedAt_ date-time of the email must be
the same or after this date-time to match the condition.
o *minSize*: "UnsignedInt" The _size_ of the email in octets must be
equal to or greater than this number to match the condition.
o *maxSize*: "UnsignedInt" The _size_ of the email in octets must be
less than this number to match the condition.
o *allInThreadHaveKeyword*: "String" All emails (including this one)
in the same thread as this email must have the given keyword to
match the condition.
Jenkins & Newman Expires September 9, 2019 [Page 40]
Internet-Draft JMAP Mail March 2019
o *someInThreadHaveKeyword*: "String" At least one email (possibly
this one) in the same thread as this email must have the given
keyword to match the condition.
o *noneInThreadHaveKeyword*: "String" All emails (including this
one) in the same thread as this email must *not* have the given
keyword to match the condition.
o *hasKeyword*: "String" This email must have the given keyword to
match the condition.
o *notKeyword*: "String" This email must not have the given keyword
to match the condition.
o *hasAttachment*: "Boolean" The "hasAttachment" property of the
email must be identical to the value given to match the condition.
o *text*: "String" Looks for the text in emails. The server MUST
look up text in the _from_, _to_, _cc_, _bcc_, _subject_ header
fields of the message, and SHOULD look inside any "text/*" or
other body parts that may be converted to text by the server. The
server MAY extend the search to any additional textual property.
o *from*: "String" Looks for the text in the _From_ header field of
the message.
o *to*: "String" Looks for the text in the _To_ header field of the
message.
o *cc*: "String" Looks for the text in the _Cc_ header field of the
message.
o *bcc*: "String" Looks for the text in the _Bcc_ header field of
the message.
o *subject*: "String" Looks for the text in the _subject_ property
of the email.
o *body*: "String" Looks for the text in one of the body parts of
the email. The server MAY exclude MIME body parts with content
media types other than "text/_" and "message/_" from consideration
in search matching. Care should be taken to match based on the
text content actually presented to an end-user by viewers for that
media type, or otherwise identified as appropriate for search
indexing. Matching document metadata uninteresting to an end-user
(e.g., markup tag and attribute names) is undesirable.
Jenkins & Newman Expires September 9, 2019 [Page 41]
Internet-Draft JMAP Mail March 2019
o *header*: "String[]" The array MUST contain either one or two
elements. The first element is the name of the header field to
match against. The second (optional) element is the text to look
for in the header field value. If not supplied, the message
matches simply if it _has_ a header field of the given name.
If zero properties are specified on the FilterCondition, the
condition MUST always evaluate to "true". If multiple properties are
specified, ALL must apply for the condition to be "true" (it is
equivalent to splitting the object into one-property conditions and
making them all the child of an AND filter operator).
The exact semantics for matching "String" fields is *deliberately not
defined* to allow for flexibility in indexing implementation, subject
to the following:
o Any syntactically correct [RFC2047] encoded sections of header
fields with a known encoding SHOULD be decoded before attempting
to match text.
o When searching inside a "text/html" body part, any text considered
markup rather than content SHOULD be ignored, including HTML tags
and most attributes, anything inside the "<head>" tag, CSS and
JavaScript. Attribute content intended for presentation to the
user such as "alt" and "title" SHOULD be considered in the search.
o Text SHOULD be matched in a case-insensitive manner.
o Text contained in either (but matched) single or double quotes
SHOULD be treated as a *phrase search*, that is a match is
required for that exact word or sequence of words, excluding the
surrounding quotation marks. Use "\"", "\'" and "\\" to match a
literal """, "'" and "\" respectively in a phrase.
o Outside of a phrase, white-space SHOULD be treated as dividing
separate tokens that may be searched for separately, but MUST all
be present for the email to match the filter.
o Tokens (not part of a phrase) MAY be matched on a whole-word basis
using stemming (so for example a text search for "bus" would match
"buses" but not "business").
4.4.2. Sorting
The following value for the "property" field on the Comparator object
MUST be supported for sorting:
Jenkins & Newman Expires September 9, 2019 [Page 42]
Internet-Draft JMAP Mail March 2019
o *receivedAt* - The _receivedAt_ date as returned in the Email
object.
The following values for the "property" field on the Comparator
object SHOULD be supported for sorting. When specifying a
"hasKeyword", "allInThreadHaveKeyword" or "someInThreadHaveKeyword"
sort, the Comparator object MUST also have a _keyword_ property.
o *size* - The _size_ as returned in the Email object.
o *from* - This is taken to be either the "name" part, or if
"null"/empty then the "email" part, of the *first* EmailAddress
object in the _from_ property. If still none, consider the value
to be the empty string.
o *to* - This is taken to be either the "name" part, or if
"null"/empty then the "email" part, of the *first* EmailAddress
object in the _to_ property. If still none, consider the value to
be the empty string.
o *subject* - This is taken to be the base subject of the email, as
defined in section 2.1 of [RFC5256].
o *sentAt* - The _sentAt_ property on the Email object.
o *hasKeyword* - This value MUST be considered "true" if the email
has the keyword given as an additional _keyword_ property on the
_Comparator_ object, or "false" otherwise.
o *allInThreadHaveKeyword* - This value MUST be considered "true"
for the email if *all* of the emails in the same thread
(regardless of mailbox) have the keyword given as an additional
_keyword_ property on the _Comparator_ object.
o *someInThreadHaveKeyword* - This value MUST be considered "true"
for the email if *any* of the emails in the same thread
(regardless of mailbox) have the keyword given as an additional
_keyword_ property on the _Comparator_ object.
The server MAY support sorting based on other properties as well. A
client can discover which properties are supported by inspecting the
server's _capabilities_ object (see section 1.3).
Example sort:
Jenkins & Newman Expires September 9, 2019 [Page 43]
Internet-Draft JMAP Mail March 2019
[{
"property": "someInThreadHaveKeyword",
"keyword": "$flagged",
"isAscending": false
}, {
"property": "subject",
"collation": "i;ascii-casemap"
}, {
"property": "receivedAt",
"isAscending": false
}]
This would sort emails in flagged threads first (the thread is
considered flagged if any email within it is flagged), and then in
subject order, then newest first for messages with the same subject.
If two emails have both identical flagged status, subject and date,
the order is server-dependent but must be stable.
4.4.3. Thread collapsing
When _collapseThreads_ is "true", then after filtering and sorting
the email list, the list is further winnowed by removing any emails
for a thread id that has already been seen (when passing through the
list sequentially). A thread will therefore only appear *once* in
the result, at the position of the first email in the list that
belongs to the thread (given the current sort/filter).
4.5. Email/queryChanges
Standard "/queryChanges" method as described in [I-D.ietf-jmap-core]
section 5.6, with the following additional request arguments:
o *collapseThreads*: "Boolean" (default: false) The
_collapseThreads_ argument that was used with _Email/query_.
4.6. Email/set
Standard "/set" method as described in [I-D.ietf-jmap-core] section
5.3. The _Email/set_ method encompasses:
o Creating a draft
o Changing the keywords of an email (e.g. unread/flagged status)
o Adding/removing an email to/from mailboxes (moving a message)
o Deleting emails
Jenkins & Newman Expires September 9, 2019 [Page 44]
Internet-Draft JMAP Mail March 2019
The format of the keywords/mailboxIds properties means that when
updating an email you can either replace the entire set of keywords/
mailboxes (by setting the full value of the property) or add/remove
individual ones using the JMAP patch syntax (see
[I-D.ietf-jmap-core], section 5.3 for the specification and section
5.7 for an example).
Due to the format of the Email object, when creating an email there
are a number of ways to specify the same information. To ensure that
the RFC5322 email to create is unambiguous, the following constraints
apply to Email objects submitted for creation:
o The _headers_ property MUST NOT be given, on either the top-level
email or an EmailBodyPart - the client must set each header field
as an individual property.
o There MUST NOT be two properties that represent the same header
field (e.g. "header:from" and "from") within the Email or
particular EmailBodyPart.
o Header fields MUST NOT be specified in parsed forms that are
forbidden for that particular field.
o Header fields beginning "Content-" MUST NOT be specified on the
Email object, only on EmailBodyPart objects.
o If a bodyStructure property is given, there MUST NOT be textBody,
htmlBody or attachments properties.
o If given, the bodyStructure EmailBodyPart MUST NOT contain a
property representing a header field that is already defined on
the top-level Email object.
o If given, textBody MUST contain exactly one body part, of type
"text/plain".
o If given, htmlBody MUST contain exactly one body part, of type
"text/html".
o Within an EmailBodyPart:
* The client may specify a partId OR a blobId but not both. If a
partId is given, this partId MUST be present in the bodyValues
property.
* The charset property MUST be omitted if a partId is given (the
part's content is included in bodyValues and the server may
choose any appropriate encoding).
Jenkins & Newman Expires September 9, 2019 [Page 45]
Internet-Draft JMAP Mail March 2019
* The size property MUST be omitted if a partId is given. If a
blobId is given, it may be included but is ignored by the
server (the size is actually calculated from the blob content
itself).
* A "Content-Transfer-Encoding" header field MUST NOT be given.
o Within an EmailBodyValue object, isEncodingProblem and isTruncated
MUST be either "false" or omitted.
Creation attempts that violate any of this SHOULD be rejected with an
"invalidProperties" error, however a server MAY choose to modify the
Email (e.g. choose between conflicting headers, use a different
content-encoding etc.) to comply with its requirements instead.
The server MAY also choose to set additional headers. If not
included, the server MUST generate and set a "Message-ID" header
field in conformance with [RFC5322] section 3.6.4, and a "Date"
header field in conformance with section 3.6.1.
The final RFC5322 email generated may be invalid. For example, if it
is a half-finished draft, the "To" field may have a value that does
not conform to the required syntax for this header field. The
message will be checked for strict conformance when submitted for
sending (see the EmailSubmission object description).
Destroying an email removes it from all mailboxes to which it
belonged. To just delete an email to trash, simply change the
"mailboxIds" property so it is now in the mailbox with "role ==
"trash"", and remove all other mailbox ids.
When emptying the trash, clients SHOULD NOT destroy emails which are
also in a mailbox other than trash. For those emails, they SHOULD
just remove the Trash mailbox from the email.
For successfully created Email objects, the _created_ response
contains the _id_, _blobId_, _threadId_ and _size_ properties of the
object.
The following extra _SetError_ types are defined:
For *create*:
o "blobNotFound": At least one blob id given for an EmailBodyPart
doesn't exist. An extra _notFound_ property of type "Id[]" MUST
be included in the error object containing every _blobId_
referenced by an EmailBodyPart that could not be found on the
server.
Jenkins & Newman Expires September 9, 2019 [Page 46]
Internet-Draft JMAP Mail March 2019
For *create* and *update*:
o "tooManyKeywords": The change to the email's keywords would exceed
a server-defined maximum.
o "tooManyMailboxes": The change to the email's mailboxes would
exceed a server-defined maximum.
4.7. Email/copy
Standard "/copy" method as described in [I-D.ietf-jmap-core] section
5.4, except only the _mailboxIds_, _keywords_ and _receivedAt_
properties may be set during the copy. This method cannot modify the
RFC5322 representation of an email.
The server MAY forbid two email objects with the same exact [RFC5322]
content, or even just with the same [RFC5322] Message-ID, to coexist
within an account; if the target account already has the email the
copy will be rejected with a standard "alreadyExists" error.
For successfully copied Email objects, the _created_ response
contains the _id_, _blobId_, _threadId_ and _size_ properties of the
new object.
4.8. Email/import
The _Email/import_ method adds [RFC5322] messages to the set of
emails in an account. The server MUST support messages with
[RFC6532] EAI headers. The messages must first be uploaded as blobs
using the standard upload mechanism. It takes the following
arguments:
o *accountId*: "Id" The id of the account to use.
o *ifInState*: "String|null" This is a state string as returned by
the _Email/get_ method. If supplied, the string must match the
current state of the account referenced by the accountId,
otherwise the method will be aborted and a "stateMismatch" error
returned. If "null", any changes will be applied to the current
state.
o *emails*: "Id[EmailImport]" A map of creation id (client
specified) to EmailImport objects
An *EmailImport* object has the following properties:
o *blobId*: "Id" The id of the blob containing the raw [RFC5322]
message.
Jenkins & Newman Expires September 9, 2019 [Page 47]
Internet-Draft JMAP Mail March 2019
o *mailboxIds*: "Id[Boolean]" The ids of the mailboxes to assign
this email to. At least one mailbox MUST be given.
o *keywords*: "String[Boolean]" (default: {}) The keywords to apply
to the email.
o *receivedAt*: "UTCDate" (default: time of most recent Received
header, or time of import on server if none) The _receivedAt_ date
to set on the email.
Each email to import is considered an atomic unit which may succeed
or fail individually. Importing successfully creates a new email
object from the data referenced by the blobId and applies the given
mailboxes, keywords and receivedAt date.
The server MAY forbid two email objects with the same exact [RFC5322]
content, or even just with the same [RFC5322] Message-ID, to coexist
within an account. In this case, it MUST reject attempts to import
an email considered a duplicate with an "alreadyExists" SetError. An
_existingId_ property of type "Id" MUST be included on the error
object with the id of the existing email. If duplicates are allowed,
the newly created Email object MUST have a separate id and
independent mutable properties to the existing object.
If the _blobId_, _mailboxIds_, or _keywords_ properties are invalid
(e.g. missing, wrong type, id not found), the server MUST reject the
import with an "invalidProperties" SetError.
If the email cannot be imported because it would take the account
over quota, the import should be rejected with an "overQuota"
SetError.
If the blob referenced is not a valid [RFC5322] message, the server
MAY modify the message to fix errors (such as removing NUL octets or
fixing invalid headers). If it does this, the _blobId_ on the
response MUST represent the new representation and therefore be
different to the _blobId_ on the EmailImport object. Alternatively,
the server MAY reject the import with an "invalidEmail" SetError.
The response has the following arguments:
o *accountId*: "Id" The id of the account used for this call.
o *oldState*: "String|null" The state string that would have been
returned by _Email/get_ on this account before making the
requested changes, or "null" if the server doesn't know what the
previous state string was.
Jenkins & Newman Expires September 9, 2019 [Page 48]
Internet-Draft JMAP Mail March 2019
o *newState*: "String" The state string that will now be returned by
_Email/get_ on this account.
o *created*: "Id[Email]|null" A map of the creation id to an object
containing the _id_, _blobId_, _threadId_ and _size_ properties
for each successfully imported Email, or "null" if none.
o *notCreated*: "Id[SetError]|null" A map of creation id to a
SetError object for each Email that failed to be created, or
"null" if all successful. The possible errors are defined above.
The following additional errors may be returned instead of the
_Email/import_ response:
"stateMismatch": An "ifInState" argument was supplied and it does not
match the current state.
4.9. Email/parse
This method allows you to parse blobs as [RFC5322] messages to get
Email objects. The server MUST support messages with [RFC6532] EAI
headers. This can be used to parse and display attached emails
without having to import them as top-level email objects in the mail
store in their own right.
The following metadata properties on the Email objects will be "null"
if requested:
o id
o mailboxIds
o keywords
o receivedAt
The _threadId_ property of the Email MAY be present if the server can
calculate which thread the Email would be assigned to were it to be
imported. Otherwise, this too is "null" if fetched.
The _Email/parse_ method takes the following arguments:
o *accountId*: "Id" The id of the account to use.
o *blobIds*: "Id[]" The ids of the blobs to parse.
o *properties*: "String[]" If supplied, only the properties listed
in the array are returned for each Email object. If omitted,
Jenkins & Newman Expires September 9, 2019 [Page 49]
Internet-Draft JMAP Mail March 2019
defaults to: [ "messageId", "inReplyTo", "references", "sender",
"from", "to", "cc", "bcc", "replyTo", "subject", "sentAt",
"hasAttachment", "preview", "bodyValues", "textBody", "htmlBody",
"attachments" ]
o *bodyProperties*: "String[]" A list of properties to fetch for
each EmailBodyPart returned. If omitted, defaults to the same
value as the Email/get "bodyProperties" default argument.
o *fetchTextBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the "textBody"
property.
o *fetchHTMLBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the "htmlBody"
property.
o *fetchAllBodyValues*: "Boolean" (default: false) If "true", the
_bodyValues_ property includes any "text/*" part in the
"bodyStructure" property.
o *maxBodyValueBytes*: "UnsignedInt" (default: 0) If greater than
zero, the _value_ property of any EmailBodyValue object returned
in _bodyValues_ MUST be truncated if necessary so it does not
exceed this number of octets in size. If "0" (the default), no
truncation occurs. The server MUST ensure the truncation results
in valid UTF-8 and does not occur mid-codepoint. If the part is
of type "text/html", the server SHOULD NOT truncate inside an HTML
tag, e.g. in the middle of "<a href="https://example.com">".
There is no requirement for the truncated form to be a balanced
tree or valid HTML (indeed, the original source may well be
neither of these things).
The response has the following arguments:
o *accountId*: "Id" The id of the account used for the call.
o *parsed*: "Id[Email]|null" A map of blob id to parsed Email
representation for each successfully parsed blob, or "null" if
none.
o *notParsable*: "Id[]|null" A list of ids given that corresponded
to blobs that could not be parsed as emails, or "null" if none.
o *notFound*: "Id[]|null" A list of blob ids given that could not be
found, or "null" if none.
Jenkins & Newman Expires September 9, 2019 [Page 50]
Internet-Draft JMAP Mail March 2019
As specified above, parsed forms of headers may only be used on
appropriate header fields. Attempting to fetch a form that is
forbidden (e.g. "header:From:asDate") MUST result in the method call
being rejected with an "invalidArguments" error.
Where a specific header is requested as a property, the
capitalization of the property name in the response MUST be identical
to that used in the request.
4.10. Examples
A client logs in for the first time. It first fetches the set of
mailboxes. Now it will display the inbox to the user, which we will
presume has mailbox id "fb666a55". The inbox may be (very!) large,
but the user's screen is only so big, so the client will just load
the start and then can load in more as necessary. The client sends
this request:
[[ "Email/query",{
"accountId": "ue150411c",
"filter": {
"inMailbox": "fb666a55"
},
"sort": [{
"isAscending": false,
"property": "receivedAt"
}],
"collapseThreads": true,
"position": 0,
"limit": 30,
"calculateTotal": true
}, "0" ],
[ "Email/get", {
"accountId": "ue150411c",
"#ids": {
"resultOf": "0",
"name": "Email/query",
"path": "/ids"
},
"properties": [
"threadId"
]
}, "1" ],
[ "Thread/get", {
"accountId": "ue150411c",
"#ids": {
"resultOf": "1",
"name": "Email/get",
Jenkins & Newman Expires September 9, 2019 [Page 51]
Internet-Draft JMAP Mail March 2019
"path": "/list/*/threadId"
}
}, "2" ],
[ "Email/get", {
"accountId": "ue150411c",
"#ids": {
"resultOf": "2",
"name": "Thread/get",
"path": "/list/*/emailIds"
},
"properties": [
"threadId",
"mailboxIds",
"keywords",
"hasAttachment",
"from",
"subject",
"receivedAt",
"size",
"preview"
]
}, "3" ]]
Let's break down the 4 method calls to see what they're doing:
"0": This asks the server for the ids of the first 30 Email objects
in the inbox, sorted newest first, ignoring messages from the same
thread as a newer message in the mailbox (i.e. it is the first 30
unique threads).
"1": Now we use a back-reference to fetch the thread ids for each of
these email ids.
"2": Another back-reference fetches the Thread object for each of
these thread ids.
"3": Finally, we fetch the information we need to display the mailbox
listing (but no more!) for every message in each of these 30 threads.
The client may aggregate this data for display, for example showing
the thread as "flagged" if any of the messages in it contain the
"$flagged" keyword.
The response from the server may look something like this:
[[ "Email/query", {
"accountId": "ue150411c",
"queryState": "09aa9a075588-780599:0",
"canCalculateChanges": true,
Jenkins & Newman Expires September 9, 2019 [Page 52]
Internet-Draft JMAP Mail March 2019
"position": 0,
"total": 115,
"ids": [ "Ma783e5cdf5f2deffbc97930a",
"M9bd17497e2a99cb345fc1d0a", ... ]
}, "0" ],
[ "Email/get", {
"accountId": "ue150411c",
"state": "780599",
"list": [{
"id": "Ma783e5cdf5f2deffbc97930a",
"threadId": "T36703c2cfe9bd5ed"
}, {
"id": "M9bd17497e2a99cb345fc1d0a",
"threadId": "T0a22ad76e9c097a1"
}, ... ],
"notFound": []
}, "1" ],
[ "Thread/get", {
"accountId": "ue150411c",
"state": "22a8728b",
"list": [{
"id": "T36703c2cfe9bd5ed",
"emailIds": [ "Ma783e5cdf5f2deffbc97930a" ]
}, {
"id": "T0a22ad76e9c097a1",
"emailIds": [ "M3b568670a63e5d100f518fa5",
"M9bd17497e2a99cb345fc1d0a" ]
}, ... ],
"notFound": []
}, "2" ],
[ "Email/get", {
"accountId": "ue150411c",
"state": "780599",
"list": [{
"id": "Ma783e5cdf5f2deffbc97930a",
"threadId": "T36703c2cfe9bd5ed",
"mailboxIds": {
"fb666a55": true
},
"keywords": {
"$seen": true,
"$flagged": true
},
"hasAttachment": true,
"from": [{
"email": "jdoe@example.com",
"name": "Jane Doe"
}],
Jenkins & Newman Expires September 9, 2019 [Page 53]
Internet-Draft JMAP Mail March 2019
"subject": "The Big Reveal",
"receivedAt": "2018-06-27T00:20:35Z",
"size": 175047,
"preview": "As you may be aware, we are required to prepare a
presentation where we wow a panel of 5 random members of the
public, on or before 30 June each year. We have drafted ..."
},
...
],
"notFound": []
}, "3" ]]
Now, on another device the user marks the first message as unread,
sending this API request:
[[ "Email/set", {
"accountId": "ue150411c",
"update": {
"Ma783e5cdf5f2deffbc97930a": {
"keywords/$seen": null
}
}
}, "0" ]]
The server applies this and sends the success response:
[[ "Email/set", {
"accountId": "ue150411c",
"oldState": "780605",
"newState": "780606",
"updated": {
"Ma783e5cdf5f2deffbc97930a": null
},
...
}, "0" ]]
The user also deletes a few messages, and then a new message arrives.
Back on our original machine, we receive a push update that the state
string for Email is now "780800". As this does not match the
client's current state, it issues a request for the changes:
Jenkins & Newman Expires September 9, 2019 [Page 54]
Internet-Draft JMAP Mail March 2019
[[ "Email/changes", {
"accountId": "ue150411c",
"sinceState": "780605",
"maxChanges": 50
}, "3" ],
[ "Email/queryChanges", {
"accountId": "ue150411c",
"filter": {
"inMailbox": "fb666a55"
},
"sort": [{
"property": "receivedAt",
"isAscending": false
}],
"collapseThreads": true,
"sinceQueryState": "09aa9a075588-780599:0",
"upToId": "Mc2781d5e856a908d8a35a564",
"maxChanges": 25,
"calculateTotal": true
}, "11" ]]
The response:
[[ "Email/changes", {
"accountId": "ue150411c",
"oldState": "780605",
"newState": "780800",
"hasMoreChanges": false,
"created": [ "Me8de6c9f6de198239b982ea2" ],
"updated": [ "Ma783e5cdf5f2deffbc97930a" ],
"destroyed": [ "M9bd17497e2a99cb345fc1d0a", ... ]
}, "3" ],
[ "Email/queryChanges", {
"accountId": "ue150411c",
"oldQueryState": "09aa9a075588-780599:0",
"newQueryState": "e35e9facf117-780615:0",
"added": [{
"id": "Me8de6c9f6de198239b982ea2",
"index": 0
}],
"removed": [ "M9bd17497e2a99cb345fc1d0a" ],
"total": 115
}, "11" ]]
The client can update its local cache of the query results by
removing "M9bd17497e2a99cb345fc1d0a" and then splicing in
"Me8de6c9f6de198239b982ea2" at position 0. As it does not have the
Jenkins & Newman Expires September 9, 2019 [Page 55]
Internet-Draft JMAP Mail March 2019
data for this new email, it will then fetch it (it also could have
done this in the same request using back-references).
It knows something has changed about "Ma783e5cdf5f2deffbc97930a", so
it will refetch the mailboxes and keywords (the only mutable
properties) for this email too.
The user composes a new message and saves a draft. The client sends:
[[ "Email/set", {
"accountId": "ue150411c",
"create": {
"k1546": {
"mailboxIds": {
"2ea1ca41b38e": true
},
"keywords": {
"$seen": true,
"$draft": true
},
"from": [{
"name": "Joe Bloggs",
"email": "joe@example.com"
}],
"to": [{
"name": "John",
"email": "john@example.com"
}],
"subject": "World domination",
"receivedAt": "2018-07-10T01:05:08Z",
"sentAt": "2018-07-10T11:05:08+10:00",
"bodyStructure": {
"type": "multipart/alternative",
"subParts": [{
"partId": "a49d",
"type": "text/html"
}, {
"partId": "bd48",
"type": "text/plain"
}]
},
"bodyValues": {
"bd48": {
"value": "I have the most brilliant plan. Let me tell you
all about it. What we do is, we",
"isTruncated": false
},
"49db": {
Jenkins & Newman Expires September 9, 2019 [Page 56]
Internet-Draft JMAP Mail March 2019
"value": "<!DOCTYPE html><html><head><title></title>
<style type=\"text/css\">div{font-size:16px}</style></head>
<body><div>I have the most brilliant plan. Let me tell you
all about it. What we do is, we</div></body></html>",
"isTruncated": false
}
}
}
}
}, "0" ]]
The server creates the message and sends the success response:
[[ "Email/set", {
"accountId": "ue150411c",
"oldState": "780823",
"newState": "780839",
"created": {
"k1546": {
"id": "Md45b47b4877521042cec0938",
"blobId": "Ge8de6c9f6de198239b982ea214e0f3a704e4af74",
"threadId": "Td957e72e89f516dc",
"size": 11721
}
},
...
}, "0" ]]
The client moves this draft to a different account. The only way to
do this is via the "/copy" method. It MUST set a new mailboxIds
property, since the current value will not be valid mailbox ids in
the destination account:
[[ "Email/copy", {
"fromAccountId": "ue150411c",
"accountId": "u6c6c41ac",
"create": {
"k45": {
"id": "Md45b47b4877521042cec0938",
"mailboxIds": {
"75a4c956": true
}
}
},
"onSuccessDestroyOriginal": true
}, "0" ]]
Jenkins & Newman Expires September 9, 2019 [Page 57]
Internet-Draft JMAP Mail March 2019
The server successfully copies the email and deletes the original.
Due to the implicit call to "Email/set", there are two responses to
the single method call, both with the same method call id:
[[ "Email/copy", {
"fromAccountId": "ue150411c",
"accountId": "u6c6c41ac",
"oldState": "7ee7e9263a6d",
"newState": "5a0d2447ed26",
"created": {
"k45": {
"id": "M138f9954a5cd2423daeafa55",
"blobId": "G6b9fb047cba722c48c611e79233d057c6b0b74e8",
"threadId": "T2f242ea424a4079a",
"size": 11721
}
},
"notCreated": null
}, "0" ],
[ "Email/set", {
"accountId": "ue150411c",
"oldState": "780839",
"newState": "780871",
"destroyed": [ "Md45b47b4877521042cec0938" ],
...
}, "0" ]]
5. Search snippets
When doing a search on a "String" property, the client may wish to
show the relevant section of the body that matches the search as a
preview instead of the beginning of the message, and to highlight any
matching terms in both this and the subject of the email. Search
snippets represent this data.
A *SearchSnippet* object has the following properties:
o *emailId*: "Id" The email id the snippet applies to.
o *subject*: "String|null" If text from the filter matches the
subject, this is the subject of the email with the following
transformations:
1. Any instance of the following three characters MUST be
replaced by an appropriate [HTML] entity: & (ampersand), <
(less-than sign), and > (greater-than sign). Other characters
MAY also be replaced with an HTML entity form.
Jenkins & Newman Expires September 9, 2019 [Page 58]
Internet-Draft JMAP Mail March 2019
2. The matching words/phrases from the filter are wrapped in HTML
"<mark></mark>" tags.
If the subject does not match text from the filter, this property
is "null".
o *preview*: "String|null" If text from the filter matches the
plain-text or HTML body, this is the relevant section of the body
(converted to plain text if originally HTML), with the same
transformations as the _subject_ property. It MUST NOT be bigger
than 255 octets in size. If the body does not contain a match for
the text from the filter, this property is "null".
It is server-defined what is a relevant section of the body for
preview. If the server is unable to determine search snippets, it
MUST return "null" for both the _subject_ and _preview_ properties.
Note, unlike most data types, a SearchSnippet DOES NOT have a
property called "id".
The following JMAP method is supported:
5.1. SearchSnippet/get
To fetch search snippets, make a call to "SearchSnippet/get". It
takes the following arguments:
o *accountId*: "Id" The id of the account to use.
o *filter*: "FilterOperator|FilterCondition|null" The same filter as
passed to Email/query; see the description of this method in
section 4.4 for details.
o *emailIds*: "Id[]" The ids of the emails to fetch snippets for.
The response has the following arguments:
o *accountId*: "Id" The id of the account used for the call.
o *list*: "SearchSnippet[]" An array of SearchSnippet objects for
the requested email ids. This may not be in the same order as the
ids that were in the request.
o *notFound*: "Id[]|null" An array of email ids requested which
could not be found, or "null" if all ids were found.
As the search snippets are derived from the message content and the
algorithm for doing so could change over time, fetching the same
Jenkins & Newman Expires September 9, 2019 [Page 59]
Internet-Draft JMAP Mail March 2019
snippets a second time MAY return a different result. However, the
previous value is not considered incorrect, so there is no state
string or update mechanism needed.
The following standard errors may be returned instead of the
_searchSnippets_ response:
"requestTooLarge": The number of _emailIds_ requested by the client
exceeds the maximum number the server is willing to process in a
single method call.
"unsupportedFilter": The server is unable to process the given
_filter_ for any reason.
5.2. Example
Here we did an Email/query to search for any email in the account
containing the word "foo", now we are fetching the search snippets
for some of the ids that were returned in the results:
[[ "SearchSnippet/get", {
"accountId": "ue150411c",
"filter": {
"text": "foo"
},
"emailIds": [
"M44200ec123de277c0c1ce69c",
"M7bcbcb0b58d7729686e83d99",
"M28d12783a0969584b6deaac0",
...
]
}, "0" ]]
Example response:
Jenkins & Newman Expires September 9, 2019 [Page 60]
Internet-Draft JMAP Mail March 2019
[[ "SearchSnippet/get", {
"accountId": "ue150411c",
"list": [{
"emailId": "M44200ec123de277c0c1ce69c",
"subject": null,
"preview": null
}, {
"emailId": "M7bcbcb0b58d7729686e83d99",
"subject": "The <mark>Foo</mark>sball competition",
"preview": "...year the <mark>foo</mark>sball competition will
be held in the Stadium de ..."
}, {
"emailId": "M28d12783a0969584b6deaac0",
"subject": null,
"preview": "...the <mark>Foo</mark>/bar method results often
returns <1 widget rather than the complete..."
},
...
],
"notFound": null
}, "0" ]]
6. Identities
An *Identity* object stores information about an email address (or
domain) the user may send from. It has the following properties:
o *id*: "Id" (immutable; server-set) The id of the identity.
o *name*: "String" (default: "") The "From" _name_ the client SHOULD
use when creating a new message from this identity.
o *email*: "String" (immutable) The "From" email address the client
MUST use when creating a new message from this identity. If the
mailbox part of the address (the section before the "@") is the
single character "*" (e.g. "*@example.com") then the client may
use any valid address ending in that domain (e.g.
"foo@example.com").
o *replyTo*: "EmailAddress[]|null" (default: null) The Reply-To
value the client SHOULD set when creating a new message from this
identity.
o *bcc*: "EmailAddress[]|null" (default: null) The Bcc value the
client SHOULD set when creating a new message from this identity.
o *textSignature*: "String" (default: "") Signature the client
SHOULD insert into new plain-text messages that will be sent from
Jenkins & Newman Expires September 9, 2019 [Page 61]
Internet-Draft JMAP Mail March 2019
this identity. Clients MAY ignore this and/or combine this with a
client-specific signature preference.
o *htmlSignature*: "String" (default: "") Signature the client
SHOULD insert into new HTML messages that will be sent from this
identity. This text MUST be an HTML snippet to be inserted into
the "<body></body>" section of the new email. Clients MAY ignore
this and/or combine this with a client-specific signature
preference.
o *mayDelete*: "Boolean" (server-set) Is the user allowed to delete
this identity? Servers may wish to set this to "false" for the
user's username or other default address. Attempts to destroy an
identity with "mayDelete: false" will be rejected with a standard
"forbidden" SetError.
See the "Addresses" header form description in the Email object for
the definition of _EmailAddress_.
Multiple identities with the same email address MAY exist, to allow
for different settings the user wants to pick between (for example
with different names/signatures).
The following JMAP methods are supported:
6.1. Identity/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1. The _ids_ argument may be "null" to fetch all at once.
6.2. Identity/changes
Standard "/changes" method as described in [I-D.ietf-jmap-core]
section 5.2.
6.3. Identity/set
Standard "/set" method as described in [I-D.ietf-jmap-core] section
5.3. The following extra _SetError_ types are defined:
For *create*:
o "forbiddenFrom": The user is not allowed to send from the address
given as the _email_ property of the identity.
Jenkins & Newman Expires September 9, 2019 [Page 62]
Internet-Draft JMAP Mail March 2019
6.4. Example
Request:
[ "Identity/get", {
"accountId": "acme"
}, "0" ]
with response:
[ "Identity/get", {
"accountId": "acme",
"state": "99401312ae-11-333",
"list": [
{
"id": "XD-3301-222-11_22AAz",
"name": "Joe Bloggs",
"email": "joe@example.com",
"replyTo": null,
"bcc": [{
"name": null,
"email": "joe+archive@example.com"
}],
"textSignature": "-- \nJoe Bloggs\nMaster of Email",
"htmlSignature": "<div><b>Joe Bloggs</b></div>
<div>Master of Email</div>",
"mayDelete": false
},
{
"id": "XD-9911312-11_22AAz",
"name": "Joe B",
"email": "*@example.com",
"replyTo": null,
"bcc": null,
"textSignature": "",
"htmlSignature": "",
"mayDelete": true
}
],
"notFound": []
}, "0" ]
7. Email submission
An *EmailSubmission* object represents the submission of an email for
delivery to one or more recipients. It has the following properties:
o *id*: "Id" (immutable; server-set) The id of the email submission.
Jenkins & Newman Expires September 9, 2019 [Page 63]
Internet-Draft JMAP Mail March 2019
o *identityId*: "Id" (immutable) The id of the identity to associate
with this submission.
o *emailId*: "Id" (immutable) The id of the email to send. The
email being sent does not have to be a draft, for example when
"redirecting" an existing email to a different address.
o *threadId*: "Id" (immutable; server-set) The thread id of the
email to send. This is set by the server to the _threadId_
property of the email referenced by the _emailId_.
o *envelope*: "Envelope|null" (immutable) Information for use when
sending via SMTP. An *Envelope* object has the following
properties:
* *mailFrom*: "Address" The email address to use as the return
address in the SMTP submission, plus any parameters to pass
with the MAIL FROM address. The JMAP server MAY allow the
address to be the empty string. When a JMAP server performs an
SMTP message submission, it MAY use the same id string for the
[RFC3461] ENVID parameter and the EmailSubmission object id.
Servers that do this MAY replace a client-provided value for
ENVID with a server-provided value.
* *rcptTo*: "Address[]" The email addresses to send the message
to, and any RCPT TO parameters to pass with the recipient.
An *Address* object has the following properties:
* *email*: "String" The email address being represented by the
object. This is a "Mailbox" as used in the Reverse-path or
Forward-path of the MAIL FROM or RCPT TO command in [RFC5321].
* *parameters*: "Object|null" Any parameters to send with the
email (either mail-parameter or rcpt-parameter as appropriate,
as specified in [RFC5321]). If supplied, each key in the
object is a parameter name, and the value either the parameter
value (type "String") or if the parameter does not take a value
then "null". For both name and value, any xtext or unitext
encodings are removed ([RFC3461], [RFC6533]) and JSON string
encoding applied.
If the _envelope_ property is "null" or omitted on creation, the
server MUST generate this from the referenced email as follows:
* *mailFrom*: The email in the _Sender_ header, if present,
otherwise the _From_ header, if present, and no parameters. If
multiple addresses are present in one of these headers, or
Jenkins & Newman Expires September 9, 2019 [Page 64]
Internet-Draft JMAP Mail March 2019
there is more than one _Sender_/_From_ header, the server
SHOULD reject the email as invalid but otherwise MUST take the
first address in the last _Sender_/_From_ header in the
[RFC5322] version of the message. If the address found from
this is not allowed by the identity associated with this
submission, the _email_ property from the identity MUST be used
instead.
* *rcptTo*: The deduplicated set of email addresses from the
_To_, _Cc_ and _Bcc_ headers, if present, with no parameters
for any of them.
o *sendAt*: "UTCDate" (immutable; server-set) The date the email
was/will be released for delivery. If the client successfully
used [RFC4865] FUTURERELEASE with the email, this MUST be the time
when the server will release the email; otherwise it MUST be the
time the EmailSubmission was created.
o *undoStatus*: "String" This represents whether the submission may
be canceled. This is server set and MUST be one of the following
values:
* "pending": It may be possible to cancel this submission.
* "final": The email has been relayed to at least one recipient
in a manner that cannot be recalled. It is no longer possible
to cancel this submission.
* "canceled": The email submission was canceled and will not be
delivered to any recipient.
On systems that do not support unsending, the value of this
property will always be "final". On systems that do support
canceling submission, it will start as "pending", and MAY
transition to "final" when the server knows it definitely cannot
recall the email, but MAY just remain "pending". If in pending
state, a client can attempt to cancel the submission by setting
this property to "canceled"; if the update succeeds, the
submission was successfully canceled and the email has not been
delivered to any of the original recipients.
o *deliveryStatus*: "String[DeliveryStatus]|null" (server-set) This
represents the delivery status for each of the email's recipients,
if known. This property MAY not be supported by all servers, in
which case it will remain "null". Servers that support it SHOULD
update the EmailSubmission object each time the status of any of
the recipients changes, even if some recipients are still being
retried. This value is a map from the email address of each
Jenkins & Newman Expires September 9, 2019 [Page 65]
Internet-Draft JMAP Mail March 2019
recipient to a _DeliveryStatus_ object. A *DeliveryStatus* object
has the following properties:
* *smtpReply*: "String" The SMTP reply string returned for this
recipient when the server last tried to relay the email, or in
a later DSN (Delivery Status Notification, as defined in
[RFC3464]) response for the email. This SHOULD be the response
to the RCPT TO stage, unless this was accepted and the email as
a whole rejected at the end of the DATA stage, in which case
the DATA stage reply SHOULD be used instead. Multi-line SMTP
responses should be concatenated to a single string as follows:
+ The hyphen following the SMTP code on all but the last line
is replaced with a space.
+ Any prefix in common with the first line is stripped from
lines after the first.
+ CRLF is replaced by a space.
For example:
550-5.7.1 Our system has detected that this message is
550 5.7.1 likely spam.
would become:
550 5.7.1 Our system has detected that this message is likely spam.
For emails relayed via an alternative to SMTP, the server MAY
generate a synthetic string representing the status instead.
If it does this, the string MUST be of the following form:
+ A 3-digit SMTP reply code, as defined in [RFC5321], section
4.2.3.
+ Then a single space character.
+ Then an SMTP Enhanced Mail System Status Code as defined in
[RFC3463], with a registry defined in [RFC5248].
+ Then a single space character.
+ Then an implementation-specific information string with a
human readable explanation of the response.
Jenkins & Newman Expires September 9, 2019 [Page 66]
Internet-Draft JMAP Mail March 2019
* *delivered*: "String" Represents whether the email has been
successfully delivered to the recipient. This MUST be one of
the following values:
+ "queued": The email is in a local mail queue and status will
change once it exits the local mail queues. The _smtpReply_
property may still change.
+ "yes": The email was successfully delivered to the mailbox
of the recipient. The _smtpReply_ property is final.
+ "no": Delivery to the recipient permanently failed. The
_smtpReply_ property is final.
+ "unknown": The final delivery status is unknown, (e.g. it
was relayed to an external machine and no further
information is available). The _smtpReply_ property may
still change if a DSN arrives.
Note, successful relaying to an external SMTP server SHOULD NOT
be taken as an indication that the email has successfully
reached the final mailbox. In this case though, the server may
receive a DSN response, if requested. If a DSN is received for
the recipient with Action equal to "delivered", as per
[RFC3464] section 2.3.3, then the _delivered_ property SHOULD
be set to "yes"; if the Action equals "failed", the property
SHOULD be set to "no". Receipt of any other DSN SHOULD NOT
affect this property. The server MAY also set this property
based on other feedback channels.
* *displayed*: "String" Represents whether the email has been
displayed to the recipient. This MUST be one of the following
values:
+ "unknown": The display status is unknown. This is the
initial value.
+ "yes": The recipient's system claims the email content has
been displayed to the recipient. Note, there is no
guarantee that the recipient has noticed, read, or
understood the content.
If an MDN is received for this recipient with Disposition-Type
(as per [RFC8098] section 3.2.6.2) equal to "displayed", this
property SHOULD be set to "yes". The server MAY also set this
property based on other feedback channels.
Jenkins & Newman Expires September 9, 2019 [Page 67]
Internet-Draft JMAP Mail March 2019
o *dsnBlobIds*: "Id[]" (server-set) A list of blob ids for Delivery
Status Notifications ([RFC3464]) received for this submission, in
order of receipt, oldest first. The blob is the whole MIME
message (with a top-level content-type of multipart/report), as
received.
o *mdnBlobIds*: "Id[]" (server-set) A list of blob ids for Message
Disposition Notifications ([RFC8098]) received for this
submission, in order of receipt, oldest first. The blob is the
whole MIME message (with a top-level content-type of multipart/
report), as received.
JMAP servers MAY choose not to expose DSN and MDN responses as Email
objects if they correlate to an EmailSubmission object. It SHOULD
only do this if it exposes them in the _dsnBlobIds_ and _mdnblobIds_
fields instead, and expects the user to be using clients capable of
fetching and displaying delivery status via the EmailSubmission
object.
For efficiency, a server MAY destroy EmailSubmission objects a
certain amount of time after the email is successfully sent or it has
finished retrying sending the email. For very basic SMTP proxies,
this MAY be immediately after creation, as it has no way to assign a
real id and return the information again if fetched later.
The following JMAP methods are supported:
7.1. EmailSubmission/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1.
7.2. EmailSubmission/changes
Standard "/changes" method as described in [I-D.ietf-jmap-core]
section 5.2.
7.3. EmailSubmission/query
Standard "/query" method as described in [I-D.ietf-jmap-core] section
5.5.
A *FilterCondition* object has the following properties, any of which
may be omitted:
o *identityIds*: "Id[]" The EmailSubmission _identityId_ property
must be in this list to match the condition.
Jenkins & Newman Expires September 9, 2019 [Page 68]
Internet-Draft JMAP Mail March 2019
o *emailIds*: "Id[]" The EmailSubmission _emailId_ property must be
in this list to match the condition.
o *threadIds*: "Id[]" The EmailSubmission _threadId_ property must
be in this list to match the condition.
o *undoStatus*: "String" The EmailSubmission _undoStatus_ property
must be identical to the value given to match the condition.
o *before*: "UTCDate" The _sendAt_ property of the EmailSubmission
object must be before this date-time to match the condition.
o *after*: "UTCDate" The _sendAt_ property of the EmailSubmission
object must be the same as or after this date-time to match the
condition.
An EmailSubmission object matches the FilterCondition if and only if
all of the given conditions match. If zero properties are specified,
it is automatically "true" for all objects.
The following EmailSubmission properties MUST be supported for
sorting:
o "emailId"
o "threadId"
o "sentAt"
7.4. EmailSubmission/queryChanges
Standard "/queryChanges" method as described in [I-D.ietf-jmap-core]
section 5.6.
7.5. EmailSubmission/set
Standard "/set" method as described in [I-D.ietf-jmap-core] section
5.3, with the following two additional request arguments:
o *onSuccessUpdateEmail*: "Id[PatchObject]|null" A map of
_EmailSubmission id_ to an object containing properties to update
on the Email object referenced by the EmailSubmission if the
create/update/destroy succeeds. (For references to
EmailSubmissions created in the same "/set" invocation, this is
equivalent to a creation-reference so the id will be the creation
id prefixed with a "#".)
Jenkins & Newman Expires September 9, 2019 [Page 69]
Internet-Draft JMAP Mail March 2019
o *onSuccessDestroyEmail*: "Id[]|null" A list of _EmailSubmission
ids_ for which the email with the corresponding emailId should be
destroyed if the create/update/destroy succeeds. (For references
to EmailSubmission creations, this is equivalent to a creation-
reference so the id will be the creation id prefixed with a "#".)
A single implicit _Email/set_ call MUST be made after all
EmailSubmissions cred in the same "/set" invocation/update/destroy
requests have been processed to perform any changes requested in
these two arguments. The response to this MUST be returned after the
_EmailSubmission/set_ response.
An email is sent by creating an EmailSubmission object. When
processing each create, the server must check that the email is
valid, and the user has sufficient authorization to send it. If the
creation succeeds, the email will be sent to the recipients given in
the envelope _rcptTo_ parameter. The server MUST remove any _Bcc_
header present on the email during delivery. The server MAY add or
remove other headers from the submitted email, or make further
alterations in accordance with the server's policy during delivery.
If the referenced email is destroyed at any point after the
EmailSubmission object is created, this MUST NOT change the behaviour
of the email submission (i.e. it does not cancel a future send). The
_emailId_ and _threadId_ properties of the submission object remain,
but trying to fetch them (with a standard Email/get call) will return
a "notFound" error if the corresponding objects have been destroyed.
Similarly, destroying an EmailSubmission object MUST NOT affect the
deliveries it represents. It purely removes the record of the email
submission. The server MAY automatically destroy EmailSubmission
objects after a certain time or in response to other triggers, and
MAY forbid the client from manually destroying EmailSubmission
objects.
If the email to be sent is larger than the server supports sending, a
standard "tooLarge" SetError MUST be returned. A _maxSize_
"UnsignedInt" property MUST be present on the SetError specifying the
maximum size of an email that may be sent, in octets.
If the email or identity id given cannot be found, the submission
creation is rejected with a standard "invalidProperties" SetError.
The following extra _SetError_ types are defined:
For *create*:
Jenkins & Newman Expires September 9, 2019 [Page 70]
Internet-Draft JMAP Mail March 2019
o "invalidEmail" - The email to be sent is invalid in some way. The
SetError SHOULD contain a property called _properties_ of type
"String[]" that lists *all* the properties of the email that were
invalid.
o "tooManyRecipients" - The envelope (supplied or generated) has
more recipients than the server allows. A _maxRecipients_
"UnsignedInt" property MUST also be present on the SetError
specifying the maximum number of allowed recipients.
o "noRecipients" - The envelope (supplied or generated) does not
have any rcptTo emails.
o "invalidRecipients" - The _rcptTo_ property of the envelope
(supplied or generated) contains at least one rcptTo value which
is not a valid email for sending to. An _invalidRecipients_
"String[]" property MUST also be present on the SetError, which is
a list of the invalid addresses.
o "forbiddenMailFrom" - The server does not permit the user to send
an email with the [RFC5321] envelope From.
o "forbiddenFrom" - The server does not permit the user to send an
email with the [RFC5322] From header of the email to be sent.
o "forbiddenToSend" - The user does not have permission to send at
all right now for some reason. A _description_ "String" property
MAY be present on the SetError object to display to the user why
they are not permitted.
For *update*:
o "cannotUnsend": The client attempted to update the _undoStatus_ of
a valid EmailSubmission object from "pending" to "canceled", but
the email cannot be unsent.
7.5.1. Example
The following example presumes a draft of the message to be sent has
already been saved, and its Email id is "M7f6ed5bcfd7e2604d1753f6c".
This call then sends the email immediately, and if successful removes
the draft flag and moves it from the Drafts folder (which has Mailbox
id "7cb4e8ee-df87-4757-b9c4-2ea1ca41b38e") to the Sent folder (which
we presume has Mailbox id "73dbcb4b-bffc-48bd-8c2a-a2e91ca672f6").
Jenkins & Newman Expires September 9, 2019 [Page 71]
Internet-Draft JMAP Mail March 2019
[[ "EmailSubmission/set", {
"accountId": "ue411d190",
"create": {
"k1490": {
"identityId": "I64588216",
"emailId": "M7f6ed5bcfd7e2604d1753f6c",
"envelope": {
"mailFrom": {
"email": "john@example.com",
"parameters": null
},
"rcptTo": [{
"email": "jane@example.com",
"parameters": null
},
...
]
}
}
},
"onSuccessUpdateEmail": {
"#k1490": {
"mailboxIds/7cb4e8ee-df87-4757-b9c4-2ea1ca41b38e": null,
"mailboxIds/73dbcb4b-bffc-48bd-8c2a-a2e91ca672f6": true,
"keywords/$draft": null
}
}
}, "0" ]]
A successful response might look like this. Note there are two
responses due to the implicit Email/set call, but both have the same
method call id as they are due to the same call in the request:
Jenkins & Newman Expires September 9, 2019 [Page 72]
Internet-Draft JMAP Mail March 2019
[[ "EmailSubmission/set", {
"accountId": "ue411d190",
"oldState": "012421s6-8nrq-4ps4-n0p4-9330r951ns21",
"newState": "355421f6-8aed-4cf4-a0c4-7377e951af36",
"created": {
"k1490": {
"id": "ES-3bab7f9a-623e-4acf-99a5-2e67facb02a0"
}
}
}, "0" ],
[ "Email/set", {
"accountId": "ue411d190",
"oldState": "778193",
"newState": "778197",
"updated": {
"M7f6ed5bcfd7e2604d1753f6c": null
}
}, "0" ]]
Suppose instead an admin has removed sending rights for the user, and
so the email submission is rejected with a "forbiddenToSend" error.
The description argument of the error is intended for display to the
user, so should be localised appropriately. Let's suppose the
request was sent with an Accept-Language header like this:
Accept-Language: de;q=0.9,en;q=0.8
The server should attempt to choose the best localisation from those
it has available based on the Accept-Language header, as described in
[I-D.ietf-jmap-core], section 3.7. If the server has English, French
and German translations it would choose German as the preferred
language and return a response like this:
[[ "EmailSubmission/set", {
"accountId": "ue411d190",
"oldState": "012421s6-8nrq-4ps4-n0p4-9330r951ns21",
"newState": "012421s6-8nrq-4ps4-n0p4-9330r951ns21",
"notCreated": {
"k1490": {
"type": "forbiddenToSend",
"description": "Verzeihung, wegen verdaechtiger Aktivitaeten Ihres Benutzerkontos haben wir den Versand von Nachrichten gesperrt. Bitte wenden Sie sich fuer Hilfe an unser Support Team."
}
}
}, "0" ]]
Jenkins & Newman Expires September 9, 2019 [Page 73]
Internet-Draft JMAP Mail March 2019
8. Vacation response
A vacation response automatically sends a reply to messages sent to a
particular account, to inform the original sender that their message
may not be read for some time. Automated message sending can produce
undesirable behaviour. To avoid this, implementors MUST follow the
recommendations set forth in [RFC3834].
The *VacationResponse* object represents the state of vacation-
response related settings for an account. It has the following
properties:
o *id*: "Id" (immutable; server-set) The id of the object. There is
only ever one vacation response object, and its id is
""singleton"".
o *isEnabled*: "Boolean" Should a vacation response be sent if an
email arrives between the _fromDate_ and _toDate_?
o *fromDate*: "UTCDate|null" If _isEnabled_ is "true" emails that
arrive on or after this date-time (but before the _toDate_ if
defined) should receive the user's vacation response. If "null",
the vacation response is effective immediately.
o *toDate*: "UTCDate|null" If _isEnabled_ is "true", emails that
arrive before this date-time (but on or after the _fromDate_ if
defined) should receive the user's vacation response. If "null",
the vacation response is effective indefinitely.
o *subject*: "String|null" The subject that will be used by the
message sent in response to emails when the vacation response is
enabled. If "null", an appropriate subject SHOULD be set by the
server.
o *textBody*: "String|null" The plain text body to send in response
to emails when the vacation response is enabled. If this is
"null", when the vacation message is sent a plain-text body part
SHOULD be generated from the _htmlBody_ but the server MAY choose
to send the response as HTML only. If both _textBody_ and
_htmlBody_ are "null", an appropriate default body SHOULD be
generated for responses by the server.
o *htmlBody*: "String|null" The HTML body to send in response to
emails when the vacation response is enabled. If this is "null",
when the vacation message is sent an HTML body part MAY be
generated from the _textBody_, or the server MAY choose to send
the response as plain-text only.
Jenkins & Newman Expires September 9, 2019 [Page 74]
Internet-Draft JMAP Mail March 2019
The following JMAP methods are supported:
8.1. VacationResponse/get
Standard "/get" method as described in [I-D.ietf-jmap-core] section
5.1.
There MUST only be exactly one VacationResponse object in an account.
It MUST have the id "singleton".
8.2. VacationResponse/set
Standard "/set" method as described in [I-D.ietf-jmap-core] section
5.3.
9. Security considerations
All security considerations of JMAP ([I-D.ietf-jmap-core]) apply to
this specification. Additional considerations specific to the data
types and functionality introduced by this document are described in
the following subsections.
9.1. EmailBodyPart value
Service providers typically perform security filtering on incoming
email and it's important that the detection of content-type and
charset for the security filter aligns with the heuristics performed
by JMAP servers. Servers that apply heuristics to determine the
content-type or charset for _EmailBodyValue_ SHOULD document the
heuristics and provide a mechanism to turn them off in the event they
are misaligned with the security filter used at a particular mailbox
host.
Automatic conversion of charsets that allow hidden channels for ASCII
text, such as UTF-7, have been problematic for security filters in
the past so server implementations can mitigate this risk by having
such conversions off-by-default and/or separately configurable.
To allow the client to restrict the volume of data it can receive in
response to a request, a maximum length may be requested for the data
returned for a textual body part. However, truncating the data may
change the semantic meaning, for example truncating a URL changes its
location. Servers that scan for links to malicious sites should take
care to either ensure truncation is not at a semantically significant
point, or to rescan the truncated value for malicious content before
returning it.
Jenkins & Newman Expires September 9, 2019 [Page 75]
Internet-Draft JMAP Mail March 2019
9.2. HTML email display
HTML message bodies provide richer formatting for emails but present
a number of security challenges, especially when embedded in a
webmail context in combination with interface HTML. Clients that
render HTML email should make careful consideration of the potential
risks, including:
o Embedded JavaScript can rewrite the email to change its content on
subsequent opening, allowing users to be mislead. In webmail
systems, if run in the same origin as the interface it can access
and exfiltrate all private data accessible to the user, including
all other emails and potentially contacts, calendar events,
settings, and credentials. It can also rewrite the interface to
undetectably phish passwords. A compromise is likely to be
persistent, not just for the duration of page load, due to
exfiltration of session credentials or installation of a service
worker that can intercept all subsequent network requests (this
however would only be possible if blob downloads are also
available on the same origin, and the service worker script is
attached to the message).
o HTML documents may load content directly from the internet, rather
than just referencing attached resources. For example you may
have an "<img>" tag with an external "src" attribute. This may
leak to the sender when a message is opened, as well as the IP
address of the recipient. Cookies may also be sent and set by the
server, allowing tracking between different emails and even
website visits and advertising profiles.
o In webmail systems, CSS can break the layout or create phishing
vulnerabilities. For example, the use of "position:fixed" can
allow an email to draw content outside of its normal bounds,
potentially clickjacking a real interface element.
o If in a webmail context and not inside a separate frame, any
styles defined in CSS rules will apply to interface elements as
well if the selector matches, allowing the interface to be
modified. Similarly, any interface styles that match elements in
the email will alter their appearance, potentially breaking the
layout of the email.
o The link text in HTML has no necessary correlation with the actual
target of the link, which can be used to make phishing attacks
more convincing.
Jenkins & Newman Expires September 9, 2019 [Page 76]
Internet-Draft JMAP Mail March 2019
o Links opened from an email or embedded external content may leak
private info in the "Referer" header sent by default in most
systems.
o Forms can be used to mimic login boxes, providing a potent
phishing vector if allowed to submit directly from the email
display.
There are a number of ways clients can mitigate these issues, and a
defence-in-depth approach that uses a combination of techniques will
provide the strongest security.
o HTML can be filtered before rendering, stripping potentially
malicious content. Sanitizing HTML correctly is tricky, and
implementers are strongly recommended to use a well-tested library
with a carefully vetted whitelist-only approach. New features
with unexpected security characteristics may be added to HTML
rendering engines in the future; a blacklist approach is likely to
result in security issues.
Subtle differences in parsing of HTML can introduce security flaws:
to filter with 100% accuracy you need to use the same parser when
sanitizing that the HTML rendering engine will use.
o Encapsulating the message in an "<iframe sandbox>", as defined in
[HTML], section 4.7.6, can help mitigate a number of risks. This
will:
* Disable JavaScript.
* Disable form submission.
* Prevent drawing outside of its bounds, or conflict with
interface CSS.
* Establish a unique anonymous origin, separate to the containing
origin.
o A strong Content Security Policy [3] can, among other things,
block JavaScript and loading of external content should it manage
to evade the filter.
o The leakage of information in the Referer header can be mitigated
with the use of a referrer policy [4].
o A "crossorigin=anonymous" attribute on tags that load remote
content can prevent cookies from being sent.
Jenkins & Newman Expires September 9, 2019 [Page 77]
Internet-Draft JMAP Mail March 2019
o If adding "target=_blank" to open links in new tabs, also add
"rel=noopener" to ensure the page that opens cannot change the URL
in the original tab to redirect the user to a phishing site.
As highly complex software components, HTML rendering engines
increase the attack surface of a client considerably, especially when
being used to process untrusted, potentially malicious content.
Serious bugs have been found in image decoders, JavaScript engines
and HTML parsers in the past, which could lead to full system
compromise. Clients using an engine should ensure they get the
latest version and continue to incorporate any security patches
released by the vendor.
9.3. Multiple part display
Messages may consist of multiple parts to be displayed sequentially
as a body. Clients MUST render each part in isolation and MUST NOT
concatenate the raw text values to render. Doing so may change the
overall semantics of the message. If the client or server is
decrypting a PGP or S/MIME encrypted part, concatenating with other
parts may leak the decrypted text to an attacker, as described in
[EFAIL].
9.4. Email submission
SMTP submission servers [RFC6409] use a number of mechanisms to
mitigate damage caused by compromised user accounts and end-user
systems including rate limiting, anti-virus/anti-spam milters (mail
filters) and other technologies. The technologies work better when
they have more information about the client connection. If JMAP
email submission is implemented as a proxy to an SMTP Submission
server, it is useful to communicate this information from the JMAP
proxy to the submission server. The de-facto [XCLIENT] extension to
SMTP can be used to do this, but use of an authenticated channel is
recommended to limit use of that extension to explicitly authorized
proxies.
JMAP servers that proxy to an SMTP Submission server SHOULD allow use
of the _submissions_ port [RFC8314]. Implementation of a mechanism
similar to SMTP XCLIENT is strongly encouraged. While SASL PLAIN
over TLS [RFC4616] is presently the mandatory-to-implement mechanism
for interoperability with SMTP submission servers [RFC4954], a JMAP
submission proxy SHOULD implement and prefer a stronger mechanism for
this use case such as TLS client certificate authentication with SASL
EXTERNAL ([RFC4422] appendix A) or SCRAM [RFC7677].
In the event the JMAP server directly relays mail to SMTP servers in
other administrative domains, then implementation of the de-facto
Jenkins & Newman Expires September 9, 2019 [Page 78]
Internet-Draft JMAP Mail March 2019
[milter] protocol is strongly encouraged to integrate with third-
party products that address security issues including anti-virus/
anti-spam, reputation protection, compliance archiving, and data loss
prevention. Proxying to a local SMTP Submission server may be a
simpler way to provide such security services.
9.5. Partial account access
A user may only have permission to access a subset of the data that
exists in an account. To avoid leaking unauthorised information, in
such a situation the server MUST treat any data the user does not
have permission to access the same as if it did not exist.
For example, suppose user A has an account with two mailboxes, Inbox
and Sent, but only shares the Inbox with user B. In this case, when
user B fetches mailboxes for this account, the server MUST behave as
though the Sent mailbox did not exist. Similarly when querying or
fetching Email objects, it MUST treat any messages that just belong
to the Sent mailbox as though they did not exist. Fetching Thread
objects MUST only return ids for Email objects the user has
permission to access; if none, the Thread again MUST be treated the
same as if it did not exist.
If the server forbids a single account from having two identical
messages, or two messages with the same "Message-Id" header field, a
user with write access can use the error returned trying to create/
import such a message to detect whether it already exists in an
inaccessible portion of the account.
9.6. Permission to send from an address
The email ecosystem has in recent years moved towards associating
trust with the From address in the [RFC5322] message, particularly
with schemes such as DMARC ([RFC7489]).
The set of Identity objects (see section 6) in an account lets the
client know which email addresses the user has permission to send
from. Each email submission is associated with an identity, and
servers SHOULD reject submissions where the "From" header field of
the email does not correspond to the associated identity.
The server MAY allow an exception to send an exact copy of an
existing message received into the mail store to another address
(otherwise known as "redirecting" or "bouncing"), although it is
RECOMMENDED the server limit this to destinations the user has
verified they also control.
Jenkins & Newman Expires September 9, 2019 [Page 79]
Internet-Draft JMAP Mail March 2019
If the user attempts to create a new Identity, the server MUST reject
it with the appropriate error if the user does not have permission to
use that email address to send from.
The [RFC5321] SMTP MAIL FROM address is often confused with the
[RFC5322] message header. The user generally only ever sees the
message header address, and this is the primary one to enforce.
However the server MUST also enforce appropriate restrictions on the
[RFC5321] MAIL FROM address to stop the user from flooding a 3rd
party address with bounces and non-delivery notices.
The JMAP submission model provides separate errors for impermissible
addresses in either context.
10. IANA considerations
10.1. JMAP capability registration for "mail"
IANA will register the "mail" JMAP Capability as follows:
Capability Name: "urn:ietf:params:jmap:mail"
Specification document: this document
Intended use: common
Change Controller: IETF
Security and privacy considerations: this document, section 9
10.2. JMAP capability registration for "submission"
IANA will register the "submission" JMAP Capability as follows:
Capability Name: "urn:ietf:params:jmap:submission"
Specification document: this document
Intended use: common
Change Controller: IETF
Security and privacy considerations: this document, section 9
Jenkins & Newman Expires September 9, 2019 [Page 80]
Internet-Draft JMAP Mail March 2019
10.3. JMAP capability registration for "vacationresponse"
IANA will register the "vacationresponse" JMAP Capability as follows:
Capability Name: "urn:ietf:params:jmap:vacationresponse"
Specification document: this document
Intended use: common
Change Controller: IETF
Security and privacy considerations: this document, section 9
10.4. IMAP and JMAP keywords registry
This document makes two changes to the IMAP keywords registry as
defined in [RFC5788].
First, the name of the registry is changed to the "IMAP and JMAP
keywords Registry".
Second, a scope column is added to the template and registry
indicating whether a keyword applies to IMAP-only, JMAP-only, both,
or reserved. All keywords presently in the IMAP keyword registry
will be marked with a scope of both. The "reserved" status can be
used to prevent future registration of a name that would be confusing
if registered. Registration of keywords with scope 'reserved' omit
most fields in the registration template (see registration of
"$recent" below for an example); such registrations are intended to
be infrequent.
IMAP clients MAY silently ignore any keywords marked JMAP-only or
reserved in the event they appear in protocol. JMAP clients MAY
silently ignore any keywords marked IMAP-only or reserved in the
event they appear in protocol.
New JMAP-only keywords are registered in the following sub-sections.
These keywords correspond to IMAP system keywords and are thus not
appropriate for use in IMAP. These keywords can not be subsequently
registered for use in IMAP except via standards action.
10.4.1. Registration of JMAP keyword '$draft'
This registers the JMAP-only keyword '$draft' in the "IMAP and JMAP
keywords Registry".
Keyword name: "$draft"
Jenkins & Newman Expires September 9, 2019 [Page 81]
Internet-Draft JMAP Mail March 2019
Scope: JMAP-only
Purpose (description): This is set when the user wants to treat the
message as a draft the user is composing. This is the JMAP
equivalent of the IMAP \Draft flag.
Private or Shared on a server: BOTH
Is it an advisory keyword or may it cause an automatic action:
Automatic. If the account has a mailbox marked with the \Drafts
special use [RFC6154], setting this flag MAY cause the message to
appear in that mailbox automatically. Certain JMAP computed values
such as _unreadEmails_ will change as a result of changing this flag.
In addition, mail clients typically will present draft messages in a
composer window rather than a viewer window.
When/by whom the keyword is set/cleared: This is typically set by a
JMAP client when referring to a draft message. One model for draft
emails would result in clearing this flag in an EmailSubmission/set
operation with an onSuccessUpdateEmail attribute. In a mailstore
shared by JMAP and IMAP, this is also set and cleared as necessary so
it matches the IMAP \Draft flag.
Related keywords: None
Related IMAP/JMAP Capabilities: SPECIAL-USE [RFC6154]
Security Considerations: A server implementing this keyword as a
shared keyword may disclose that a user considers the message a draft
message. This information would be exposed to other users with read
permission for the mailbox keywords.
Published specification (recommended): this document
Person & email address to contact for further information: (editor-
contact-goes-here)
Intended usage: COMMON
Owner/Change controller: IESG
10.4.2. Registration of JMAP keyword '$seen'
This registers the JMAP-only keyword '$seen' in the "IMAP and JMAP
keywords Registry".
Keyword name: "$seen"
Jenkins & Newman Expires September 9, 2019 [Page 82]
Internet-Draft JMAP Mail March 2019
Scope: JMAP-only
Purpose (description): This is set when the user wants to treat the
message as read. This is the JMAP equivalent of the IMAP \Seen flag.
Private or Shared on a server: BOTH
Is it an advisory keyword or may it cause an automatic action:
Advisory. However, certain JMAP computed values such as
_unreadEmails_ will change as a result of changing this flag.
When/by whom the keyword is set/cleared: This is set by a JMAP client
when it presents the message content to the user; clients often offer
an option to clear this flag. In a mailstore shared by JMAP and
IMAP, this is also set and cleared as necessary so it matches the
IMAP \Seen flag.
Related keywords: None
Related IMAP/JMAP Capabilities: None
Security Considerations: A server implementing this keyword as a
shared keyword may disclose that a user considers the message to have
been read. This information would be exposed to other users with
read permission for the mailbox keywords.
Published specification (recommended): this document
Person & email address to contact for further information: (editor-
contact-goes-here)
Intended usage: COMMON
Owner/Change controller: IESG
10.4.3. Registration of JMAP keyword '$flagged'
This registers the JMAP-only keyword '$flagged' in the "IMAP and JMAP
keywords Registry".
Keyword name: "$flagged"
Scope: JMAP-only
Purpose (description): This is set when the user wants to treat the
message as flagged for urgent/special attention. This is the JMAP
equivalent of the IMAP \Flagged flag.
Jenkins & Newman Expires September 9, 2019 [Page 83]
Internet-Draft JMAP Mail March 2019
Private or Shared on a server: BOTH
Is it an advisory keyword or may it cause an automatic action:
Automatic. If the account has a mailbox marked with the \Flagged
special use [RFC6154], setting this flag MAY cause the message to
appear in that mailbox automatically.
When/by whom the keyword is set/cleared: JMAP clients typically allow
a user to set/clear this flag as desired. In a mailstore shared by
JMAP and IMAP, this is also set and cleared as necessary so it
matches the IMAP \Flagged flag.
Related keywords: None
Related IMAP/JMAP Capabilities: SPECIAL-USE [RFC6154]
Security Considerations: A server implementing this keyword as a
shared keyword may disclose that a user considers the message as
flagged for urgent/special attention. This information would be
exposed to other users with read permission for the mailbox keywords.
Published specification (recommended): this document
Person & email address to contact for further information: (editor-
contact-goes-here)
Intended usage: COMMON
Owner/Change controller: IESG
10.4.4. Registration of JMAP keyword '$answered'
This registers the JMAP-only keyword '$answered' in the "IMAP and
JMAP keywords Registry".
Keyword name: "$answered"
Scope: JMAP-only
Purpose (description): This is set when the message has been
answered.
Private or Shared on a server: BOTH
Is it an advisory keyword or may it cause an automatic action:
Advisory.
Jenkins & Newman Expires September 9, 2019 [Page 84]
Internet-Draft JMAP Mail March 2019
When/by whom the keyword is set/cleared: JMAP clients typically set
this when submitting a reply or answer to the message. It may be set
by the EmailSubmission/set operation with an onSuccessUpdateEmail
attribute. In a mailstore shared by JMAP and IMAP, this is also set
and cleared as necessary so it matches the IMAP \Answered flag.
Related keywords: None
Related IMAP/JMAP Capabilities: None
Security Considerations: A server implementing this keyword as a
shared keyword may disclose that a user has replied to a message.
This information would be exposed to other users with read permission
for the mailbox keywords.
Published specification (recommended): this document
Person & email address to contact for further information: (editor-
contact-goes-here)
Intended usage: COMMON
Owner/Change controller: IESG
10.4.5. Registration of '$recent' keyword
This registers the keyword '$recent' in the "IMAP and JMAP keywords
Registry".
Keyword name: "$recent"
Scope: reserved
Purpose (description): This keyword is not used to avoid confusion
with the IMAP \Recent system flag.
Published specification (recommended): this document
Person & email address to contact for further information: (editor-
contact-goes-here)
Owner/Change controller: IESG
10.5. Registration of "inbox" role in
This registers the JMAP-only "inbox" attribute in the "IMAP Mailbox
Name Attributes Registry", as established in [RFC8457].
Jenkins & Newman Expires September 9, 2019 [Page 85]
Internet-Draft JMAP Mail March 2019
Attribute Name: Inbox
Description: New mail is delivered here by default.
Reference: This document, section 10.5.
Usage Notes: JMAP only
10.6. JMAP Error Codes registry
The following sub-sections register several new error codes in the
JMAP Error Codes registry, as defined in [I-D.ietf-jmap-core].
10.6.1. mailboxHasChild
JMAP Error Code: mailboxHasChild
Intended use: common
Change controller: IETF
Reference: This document, section 2.5
Description: The mailbox still has at least one child mailbox. The
client MUST remove these before it can delete the parent mailbox.
10.6.2. mailboxHasEmail
JMAP Error Code: mailboxHasEmail
Intended use: common
Change controller: IETF
Reference: This document, section 2.5
Description: The mailbox has at least one message assigned to it and
the onDestroyRemoveMessages argument was false.
10.6.3. blobNotFound
JMAP Error Code: blobNotFound
Intended use: common
Change controller: IETF
Reference: This document, section 4.6
Jenkins & Newman Expires September 9, 2019 [Page 86]
Internet-Draft JMAP Mail March 2019
Description: At least one blob id referenced in the object doesn't
exist.
10.6.4. tooManyKeywords
JMAP Error Code: tooManyKeywords
Intended use: common
Change controller: IETF
Reference: This document, section 4.6
Description: The change to the email's keywords would exceed a
server-defined maximum.
10.6.5. tooManyMailboxes
JMAP Error Code: tooManyMailboxes
Intended use: common
Change controller: IETF
Reference: This document, section 4.6
Description: The change to the email's mailboxes would exceed a
server-defined maximum.
10.6.6. invalidEmail
JMAP Error Code: invalidEmail
Intended use: common
Change controller: IETF
Reference: This document, section 7.5
Description: The email to be sent is invalid in some way.
10.6.7. tooManyRecipients
JMAP Error Code: tooManyRecipients
Intended use: common
Change controller: IETF
Jenkins & Newman Expires September 9, 2019 [Page 87]
Internet-Draft JMAP Mail March 2019
Reference: This document, section 7.5
Description: The RFC5321 envelope (supplied or generated) has more
recipients than the server allows.
10.6.8. noRecipients
JMAP Error Code: noRecipients
Intended use: common
Change controller: IETF
Reference: This document, section 7.5
Description: The RFC5321 envelope (supplied or generated) does not
have any rcptTo emails.
10.6.9. invalidRecipients
JMAP Error Code: invalidRecipients
Intended use: common
Change controller: IETF
Reference: This document, section 7.5
Description: The rcptTo property of the RFC5321 envelope (supplied or
generated) contains at least one rcptTo value which is not a valid
email for sending to.
10.6.10. forbiddenMailFrom
JMAP Error Code: forbiddenMailFrom
Intended use: common
Change controller: IETF
Reference: This document, section 7.5
Description: The server does not permit the user to send an email
with the RFC5321 envelope From.
Jenkins & Newman Expires September 9, 2019 [Page 88]
Internet-Draft JMAP Mail March 2019
10.6.11. forbiddenFrom
JMAP Error Code: forbiddenFrom
Intended use: common
Change controller: IETF
Reference: This document, sections 6.3 and 7.5
Description: The server does not permit the user to send an email
with the RFC5322 From header field of the email to be sent.
10.6.12. forbiddenToSend
JMAP Error Code: forbiddenToSend
Intended use: common
Change controller: IETF
Reference: This document, section 7.5
Description: The user does not have permission to send at all right
now.
11. References
11.1. Normative References
[HTML] Faulkner, S., Eicholz, A., Leithead, T., Danilo, A., and
S. Moon, "HTML 5.2", 2017,
<https://www.w3.org/TR/html52/>.
[I-D.ietf-jmap-core]
Jenkins, N. and C. Newman, "JSON Meta Application
Protocol", draft-ietf-jmap-core-14 (work in progress),
January 2019.
[RFC1870] Klensin, J., Freed, N., and K. Moore, "SMTP Service
Extension for Message Size Declaration", STD 10, RFC 1870,
DOI 10.17487/RFC1870, November 1995,
<https://www.rfc-editor.org/info/rfc1870>.
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, DOI 10.17487/RFC2045, November 1996,
<https://www.rfc-editor.org/info/rfc2045>.
Jenkins & Newman Expires September 9, 2019 [Page 89]
Internet-Draft JMAP Mail March 2019
[RFC2047] Moore, K., "MIME (Multipurpose Internet Mail Extensions)
Part Three: Message Header Extensions for Non-ASCII Text",
RFC 2047, DOI 10.17487/RFC2047, November 1996,
<https://www.rfc-editor.org/info/rfc2047>.
[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>.
[RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and Encoded
Word Extensions: Character Sets, Languages, and
Continuations", RFC 2231, DOI 10.17487/RFC2231, November
1997, <https://www.rfc-editor.org/info/rfc2231>.
[RFC2369] Neufeld, G. and J. Baer, "The Use of URLs as Meta-Syntax
for Core Mail List Commands and their Transport through
Message Header Fields", RFC 2369, DOI 10.17487/RFC2369,
July 1998, <https://www.rfc-editor.org/info/rfc2369>.
[RFC2392] Levinson, E., "Content-ID and Message-ID Uniform Resource
Locators", RFC 2392, DOI 10.17487/RFC2392, August 1998,
<https://www.rfc-editor.org/info/rfc2392>.
[RFC2557] Palme, J., Hopmann, A., and N. Shelness, "MIME
Encapsulation of Aggregate Documents, such as HTML
(MHTML)", RFC 2557, DOI 10.17487/RFC2557, March 1999,
<https://www.rfc-editor.org/info/rfc2557>.
[RFC2852] Newman, D., "Deliver By SMTP Service Extension", RFC 2852,
DOI 10.17487/RFC2852, June 2000,
<https://www.rfc-editor.org/info/rfc2852>.
[RFC3282] Alvestrand, H., "Content Language Headers", RFC 3282,
DOI 10.17487/RFC3282, May 2002,
<https://www.rfc-editor.org/info/rfc3282>.
[RFC3461] Moore, K., "Simple Mail Transfer Protocol (SMTP) Service
Extension for Delivery Status Notifications (DSNs)",
RFC 3461, DOI 10.17487/RFC3461, January 2003,
<https://www.rfc-editor.org/info/rfc3461>.
[RFC3463] Vaudreuil, G., "Enhanced Mail System Status Codes",
RFC 3463, DOI 10.17487/RFC3463, January 2003,
<https://www.rfc-editor.org/info/rfc3463>.
Jenkins & Newman Expires September 9, 2019 [Page 90]
Internet-Draft JMAP Mail March 2019
[RFC3464] Moore, K. and G. Vaudreuil, "An Extensible Message Format
for Delivery Status Notifications", RFC 3464,
DOI 10.17487/RFC3464, January 2003,
<https://www.rfc-editor.org/info/rfc3464>.
[RFC3834] Moore, K., "Recommendations for Automatic Responses to
Electronic Mail", RFC 3834, DOI 10.17487/RFC3834, August
2004, <https://www.rfc-editor.org/info/rfc3834>.
[RFC4314] Melnikov, A., "IMAP4 Access Control List (ACL) Extension",
RFC 4314, DOI 10.17487/RFC4314, December 2005,
<https://www.rfc-editor.org/info/rfc4314>.
[RFC4422] Melnikov, A., Ed. and K. Zeilenga, Ed., "Simple
Authentication and Security Layer (SASL)", RFC 4422,
DOI 10.17487/RFC4422, June 2006,
<https://www.rfc-editor.org/info/rfc4422>.
[RFC4616] Zeilenga, K., Ed., "The PLAIN Simple Authentication and
Security Layer (SASL) Mechanism", RFC 4616,
DOI 10.17487/RFC4616, August 2006,
<https://www.rfc-editor.org/info/rfc4616>.
[RFC4865] White, G. and G. Vaudreuil, "SMTP Submission Service
Extension for Future Message Release", RFC 4865,
DOI 10.17487/RFC4865, May 2007,
<https://www.rfc-editor.org/info/rfc4865>.
[RFC4954] Siemborski, R., Ed. and A. Melnikov, Ed., "SMTP Service
Extension for Authentication", RFC 4954,
DOI 10.17487/RFC4954, July 2007,
<https://www.rfc-editor.org/info/rfc4954>.
[RFC5198] Klensin, J. and M. Padlipsky, "Unicode Format for Network
Interchange", RFC 5198, DOI 10.17487/RFC5198, March 2008,
<https://www.rfc-editor.org/info/rfc5198>.
[RFC5248] Hansen, T. and J. Klensin, "A Registry for SMTP Enhanced
Mail System Status Codes", BCP 138, RFC 5248,
DOI 10.17487/RFC5248, June 2008,
<https://www.rfc-editor.org/info/rfc5248>.
[RFC5256] Crispin, M. and K. Murchison, "Internet Message Access
Protocol - SORT and THREAD Extensions", RFC 5256,
DOI 10.17487/RFC5256, June 2008,
<https://www.rfc-editor.org/info/rfc5256>.
Jenkins & Newman Expires September 9, 2019 [Page 91]
Internet-Draft JMAP Mail March 2019
[RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321,
DOI 10.17487/RFC5321, October 2008,
<https://www.rfc-editor.org/info/rfc5321>.
[RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
DOI 10.17487/RFC5322, October 2008,
<https://www.rfc-editor.org/info/rfc5322>.
[RFC5788] Melnikov, A. and D. Cridland, "IMAP4 Keyword Registry",
RFC 5788, DOI 10.17487/RFC5788, March 2010,
<https://www.rfc-editor.org/info/rfc5788>.
[RFC6154] Leiba, B. and J. Nicolson, "IMAP LIST Extension for
Special-Use Mailboxes", RFC 6154, DOI 10.17487/RFC6154,
March 2011, <https://www.rfc-editor.org/info/rfc6154>.
[RFC6409] Gellens, R. and J. Klensin, "Message Submission for Mail",
STD 72, RFC 6409, DOI 10.17487/RFC6409, November 2011,
<https://www.rfc-editor.org/info/rfc6409>.
[RFC6532] Yang, A., Steele, S., and N. Freed, "Internationalized
Email Headers", RFC 6532, DOI 10.17487/RFC6532, February
2012, <https://www.rfc-editor.org/info/rfc6532>.
[RFC6533] Hansen, T., Ed., Newman, C., and A. Melnikov,
"Internationalized Delivery Status and Disposition
Notifications", RFC 6533, DOI 10.17487/RFC6533, February
2012, <https://www.rfc-editor.org/info/rfc6533>.
[RFC6710] Melnikov, A. and K. Carlberg, "Simple Mail Transfer
Protocol Extension for Message Transfer Priorities",
RFC 6710, DOI 10.17487/RFC6710, August 2012,
<https://www.rfc-editor.org/info/rfc6710>.
[RFC7677] Hansen, T., "SCRAM-SHA-256 and SCRAM-SHA-256-PLUS Simple
Authentication and Security Layer (SASL) Mechanisms",
RFC 7677, DOI 10.17487/RFC7677, November 2015,
<https://www.rfc-editor.org/info/rfc7677>.
[RFC8098] Hansen, T., Ed. and A. Melnikov, Ed., "Message Disposition
Notification", STD 85, RFC 8098, DOI 10.17487/RFC8098,
February 2017, <https://www.rfc-editor.org/info/rfc8098>.
[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>.
Jenkins & Newman Expires September 9, 2019 [Page 92]
Internet-Draft JMAP Mail March 2019
[RFC8314] Moore, K. and C. Newman, "Cleartext Considered Obsolete:
Use of Transport Layer Security (TLS) for Email Submission
and Access", RFC 8314, DOI 10.17487/RFC8314, January 2018,
<https://www.rfc-editor.org/info/rfc8314>.
[RFC8457] Leiba, B., Ed., "IMAP "$Important" Keyword and
"\Important" Special-Use Attribute", RFC 8457,
DOI 10.17487/RFC8457, September 2018,
<https://www.rfc-editor.org/info/rfc8457>.
[RFC8474] Gondwana, B., Ed., "IMAP Extension for Object
Identifiers", RFC 8474, DOI 10.17487/RFC8474, September
2018, <https://www.rfc-editor.org/info/rfc8474>.
11.2. Informative References
[EFAIL] Poddebniak, D., Dresen, C., Mueller, J., Ising, F.,
Schinzel, S., Friedberger, S., Somorovsky, J., and J.
Schwenk, "Efail: Breaking S/MIME and OpenPGP Email
Encryption using Exfiltration Channels", 2018,
<https://www.usenix.org/system/files/conference/
usenixsecurity18/sec18-poddebniak.pdf>.
[milter] Unknown, "Postfix before-queue Milter support", 2019,
<http://www.postfix.org/MILTER_README.html>.
[RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
4rev1", RFC 3501, DOI 10.17487/RFC3501, March 2003,
<https://www.rfc-editor.org/info/rfc3501>.
[RFC7489] Kucherawy, M., Ed. and E. Zwicky, Ed., "Domain-based
Message Authentication, Reporting, and Conformance
(DMARC)", RFC 7489, DOI 10.17487/RFC7489, March 2015,
<https://www.rfc-editor.org/info/rfc7489>.
[XCLIENT] Unknown, "Postfix XCLIENT Howto", 2019,
<http://www.postfix.org/XCLIENT_README.html>.
11.3. URIs
[1] https://www.iana.org/assignments/imap-mailbox-name-attributes/
imap-mailbox-name-attributes.xhtml
[2] https://www.iana.org/assignments/imap-keywords/imap-
keywords.xhtml
[3] https://www.w3.org/TR/CSP3/
Jenkins & Newman Expires September 9, 2019 [Page 93]
Internet-Draft JMAP Mail March 2019
[4] https://www.w3.org/TR/referrer-policy/
Authors' Addresses
Neil Jenkins
FastMail
PO Box 234, Collins St West
Melbourne VIC 8007
Australia
Email: neilj@fastmailteam.com
URI: https://www.fastmail.com
Chris Newman
Oracle
440 E. Huntington Dr., Suite 400
Arcadia CA 91006
United States of America
Email: chris.newman@oracle.com
Jenkins & Newman Expires September 9, 2019 [Page 94]
