JMAP N. Jenkins
Internet-Draft FastMail
Intended status: Standards Track July 16, 2017
Expires: January 17, 2018
JSON Meta Application Protocol
draft-ietf-jmap-core-01
Abstract
This document specifies a protocol for synchronising JSON-based data
objects efficiently, with support for push and out-of-band binary
data upload/download.
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 http://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 January 17, 2018.
Copyright Notice
Copyright (c) 2017 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
(http://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
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Jenkins Expires January 17, 2018 [Page 1]
Internet-Draft JMAP July 2017
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 4
1.2. JSON as the data encoding format . . . . . . . . . . . . 4
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
1.3.1. User . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3.2. Accounts . . . . . . . . . . . . . . . . . . . . . . 5
1.3.3. Data types and records . . . . . . . . . . . . . . . 5
1.4. Ids . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5. The JMAP API model . . . . . . . . . . . . . . . . . . . 6
2. Authentication . . . . . . . . . . . . . . . . . . . . . . . 6
2.1. Service autodiscovery . . . . . . . . . . . . . . . . . . 6
2.2. Getting an access token . . . . . . . . . . . . . . . . . 7
2.2.1. 200: Success, but more authorization required. . . . 8
2.2.2. 201: Authentication is complete, access token
created. . . . . . . . . . . . . . . . . . . . . . . 11
2.2.3. 400: Malformed request . . . . . . . . . . . . . . . 13
2.2.4. 403: Authentication step failed, but client may try
again . . . . . . . . . . . . . . . . . . . . . . . . 14
2.2.5. 404: Not found . . . . . . . . . . . . . . . . . . . 14
2.2.6. 410: Restart authentication . . . . . . . . . . . . . 14
2.2.7. 429: Rate limited . . . . . . . . . . . . . . . . . . 14
2.2.8. 500: Internal server error . . . . . . . . . . . . . 14
2.2.9. 503: Service unavailable . . . . . . . . . . . . . . 14
2.3. Refetching URL endpoints . . . . . . . . . . . . . . . . 14
2.3.1. 201: Authentication is complete, access token
created. . . . . . . . . . . . . . . . . . . . . . . 15
2.3.2. 403: Restart authentication . . . . . . . . . . . . . 15
2.3.3. 404: Not found . . . . . . . . . . . . . . . . . . . 15
2.3.4. 500: Internal server error . . . . . . . . . . . . . 16
2.3.5. 503: Service unavailable . . . . . . . . . . . . . . 16
2.4. Revoking an access token . . . . . . . . . . . . . . . . 16
2.4.1. 204: Success . . . . . . . . . . . . . . . . . . . . 16
2.4.2. 401: Unauthorized . . . . . . . . . . . . . . . . . . 16
2.5. Authenticating HTTP requests . . . . . . . . . . . . . . 16
2.5.1. Signed GET requests . . . . . . . . . . . . . . . . . 17
3. Structured data exchange . . . . . . . . . . . . . . . . . . 17
3.1. Making an API request . . . . . . . . . . . . . . . . . . 18
3.1.1. 200: OK . . . . . . . . . . . . . . . . . . . . . . . 18
3.1.2. 400: Bad Request . . . . . . . . . . . . . . . . . . 18
3.1.3. 401: Unauthorized . . . . . . . . . . . . . . . . . . 18
3.1.4. 404: Not Found . . . . . . . . . . . . . . . . . . . 18
3.1.5. 413: Payload Too Large . . . . . . . . . . . . . . . 18
3.1.6. 429: Rate limited . . . . . . . . . . . . . . . . . . 19
3.1.7. 500: Internal Server Error . . . . . . . . . . . . . 19
3.1.8. 503: Service Unavailable . . . . . . . . . . . . . . 19
3.2. The structure of an API request . . . . . . . . . . . . . 19
Jenkins Expires January 17, 2018 [Page 2]
Internet-Draft JMAP July 2017
3.3. Errors . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.4. Vendor-specific extensions . . . . . . . . . . . . . . . 21
3.5. Security . . . . . . . . . . . . . . . . . . . . . . . . 21
3.6. Concurrency . . . . . . . . . . . . . . . . . . . . . . . 21
3.7. The Number datatype . . . . . . . . . . . . . . . . . . . 21
3.8. The Date datatypes . . . . . . . . . . . . . . . . . . . 22
3.9. Use of null . . . . . . . . . . . . . . . . . . . . . . . 22
3.10. CRUD methods . . . . . . . . . . . . . . . . . . . . . . 22
3.10.1. getFoos . . . . . . . . . . . . . . . . . . . . . . 22
3.10.2. getFooUpdates . . . . . . . . . . . . . . . . . . . 24
3.10.3. setFoos . . . . . . . . . . . . . . . . . . . . . . 26
3.11. Querying data . . . . . . . . . . . . . . . . . . . . . . 29
3.11.1. getFooList . . . . . . . . . . . . . . . . . . . . . 29
3.11.2. getFooListUpdates . . . . . . . . . . . . . . . . . 31
4. Downloading binary data . . . . . . . . . . . . . . . . . . . 33
4.1. 200: OK . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.2. 401: Unauthorized . . . . . . . . . . . . . . . . . . . . 34
4.3. 404: Not Found . . . . . . . . . . . . . . . . . . . . . 34
4.4. 503: Service Unavailable . . . . . . . . . . . . . . . . 35
5. Uploading binary data . . . . . . . . . . . . . . . . . . . . 35
5.1. 201: File uploaded successfully . . . . . . . . . . . . . 35
5.2. 400: Bad request . . . . . . . . . . . . . . . . . . . . 36
5.3. 401: Unauthorized . . . . . . . . . . . . . . . . . . . . 36
5.4. 404: Not Found . . . . . . . . . . . . . . . . . . . . . 36
5.5. 413: Request Entity Too Large . . . . . . . . . . . . . . 36
5.6. 415: Unsupported Media Type . . . . . . . . . . . . . . . 36
5.6.1. 429: Rate limited . . . . . . . . . . . . . . . . . . 37
5.7. 503: Service Unavailable . . . . . . . . . . . . . . . . 37
6. Push . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
6.1. Event Source . . . . . . . . . . . . . . . . . . . . . . 38
6.2. Web hook . . . . . . . . . . . . . . . . . . . . . . . . 38
6.2.1. setPushCallback . . . . . . . . . . . . . . . . . . . 39
6.2.2. getPushCallback . . . . . . . . . . . . . . . . . . . 39
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.1. Normative References . . . . . . . . . . . . . . . . . . 40
7.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 41
1. Introduction
JMAP 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 is for the generic mechanism of authentication and
synchronisation. Further specifications define the data models for
different data types that may be synchronised via JMAP.
Jenkins Expires January 17, 2018 [Page 3]
Internet-Draft JMAP July 2017
JMAP is designed to make efficient use of limited network resources.
Multiple API calls may be batched in a single request to the server,
reducing round trips and improving battery life on mobile devices.
Push connections remove the need for polling, and an efficient delta
update mechanism ensures a minimum of data is transferred.
JMAP is designed to be horizontally scalable to a very large number
of users. This is facilitated by the separate end points for users
after login, the separation of binary and structured data, and a
shared data model that does not allow data dependencies between
accounts.
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
The underlying format used for this specification is JSON.
Consequently, the terms "object" and "array" as well as the four
primitive types (strings, numbers, booleans, and null) are to be
interpreted as described in Section 1 of [RFC7159].
Some examples in this document contain "partial" JSON documents used
for illustrative purposes. In these examples, three periods "..."
are used to indicate a portion of the document that has been removed
for compactness.
Types signatures are given for all JSON objects in this document.
The following conventions are used:
o "Boolean|String" - The value is either a JSON "Boolean" value, or
a JSON "String" value.
o "Foo" - Any name that is not a native JSON type means an object
for which the properties (and their types) are defined elsewhere
within this document.
o "Foo[]" - An array of objects of type "Foo".
o "String[Foo]" - A JSON "Object" being used as a map (associative
array), where all the values are of type "Foo".
1.2. JSON as the data encoding format
JSON is a text-based data interchange format as specified in
[RFC7159]. The I-JSON format defined in [RFC7493] is a strict subset
of this, adding restrictions to avoid potentially confusing scenarios
Jenkins Expires January 17, 2018 [Page 4]
Internet-Draft JMAP July 2017
(for example, it mandates that an object MUST NOT have two properties
with the same key).
All data sent from the client to the server or from the server to the
client (except binary file upload/download) MUST be valid I-JSON
according to the RFC, and is therefore case-sensitive and encoded in
UTF-8 ([RFC3629]).
1.3. Terminology
1.3.1. User
A user represents a set of permissions relating to what data can be
seen. To access data in JMAP, you first authenticate as a particular
user.
1.3.2. Accounts
An account is a collection of data.
All data, other than the Account objects themselves, belong to a
single account. A single account may contain an arbitrary set of
data, for example a collection of mail, contacts and calendars. Most
operations in JMAP are isolated to a single account; there are a few
explicit operations to copy data between them. Certain properties
are guaranteed for data within the same account, for example
uniqueness of ids within a type in that account.
An account is not the same as a user, although it is common for the
primary account to directly belong to the user. For example, you may
have an account that contains data for a group or business, to which
multiple users have access. Users may also have access to accounts
belonging to another user if that user is sharing some of their data.
1.3.3. Data types and records
JMAP provides a uniform interface for creating, retrieving, updating
and deleting various types of objects. A *data type* is a collection
of named, typed properties, just like the schema for a database
table. Each instance of a data type is called a *record*.
1.4. Ids
All object ids are assigned by the server, and are immutable. They
MUST be unique among all objects of the *same type* within the *same
account*. Ids may clash across accounts, or for two objects of
different types within the same account.
Jenkins Expires January 17, 2018 [Page 5]
Internet-Draft JMAP July 2017
Ids are always "String"s. An id MUST be a valid UTF-8 string of at
least 1 character in length and maximum 256 bytes in size, but MUST
NOT start with the "#" character, as this is reserved for doing back
references during object creation (see the _setFoos_ description).
1.5. The JMAP API model
All data exchanges are authenticated using an access token.
Authentication is covered in section 2.
An authenticated client may exchange data with the server using four
different mechanisms:
1. The client may make an API request to the server to get or set
structured data. This request consists of an ordered series of
method calls. These are processed by the server, which then
returns an ordered series of responses. This is described in
section 3.
2. The client may download binary files from the server. This is
detailed in section 4.
3. The client may upload binary files to the server. This is
specified in section 5.
4. The client may connect to a push channel on the server, to be
notified when data has changed. This is explained in section 6.
2. Authentication
When connecting to any JMAP server, the client must first gain an
access token. It cannot just use a username/password directly. This
allows the server to know (and show the user) which clients currently
have access to the account, and to be able to revoke access
individually.
The server may support multiple different mechanisms for
authenticating a user to gain the access token. It is expected that
further types may be added in future extensions to the JMAP
specification.
2.1. Service autodiscovery
To begin authentication, the client needs to know the authentication
URL for the JMAP server.
There are two standardised autodiscovery methods in use for internet
protocols:
Jenkins Expires January 17, 2018 [Page 6]
Internet-Draft JMAP July 2017
o *DNS srv* See [RFC6186] and [RFC6764]
o *.well-known/servicename* See [RFC5785]
A JMAP-supporting host for the domain "example.com" SHOULD publish a
SRV record "_jmaps._tcp.example.com" which gives a _hostname_ and
_port_ (usually port "443"). The authentication URL is then
"https://${hostname}[:${port}]/.well-known/jmap" (following any
redirects).
If the client has a username in the form of an email address, it MAY
use the domain portion of this to attempt autodiscovery of the JMAP
server.
To support clients that are unable to do SRV lookups, the server
SHOULD make the _hostname_ the same domain as the username if
possible.
2.2. Getting an access token
Authorization always starts with the client making a POST request to
the authentication URL (found either via service autodiscovery or
manual entry). The request MUST be of type "application/json" and
specify an "Accept: application/json" header. The body of the
request MUST be a single JSON object, encoded in UTF-8, with the
following properties:
o *username*: "String" The username the client wishes to
authenticate. This is normally the primary email address of the
user.
o *clientName*: "String" The name of the client software. e.g.
"Mozilla Thunderbird".
o *clientVersion*: "String" Information to identify the version of
the client. This MUST change for any changed client code (e.g. a
version control tag or counter for development software) and
SHOULD sort lexically later for newer versions.
o *deviceName*: "String" A human-friendly string to identify the
device making the request, e.g. "Joe Blogg's iPhone".
The server may use the client/device information to help identify the
login to the user in a login log or other security reporting.
Although hopefully unnecessary, they may also be helpful for working
around client bugs in the future.
The server will respond with one of the following HTTP status codes:
Jenkins Expires January 17, 2018 [Page 7]
Internet-Draft JMAP July 2017
2.2.1. 200: Success, but more authorization required.
The response body will be a single JSON object with the following
properties.
o *loginId*: "String" An id from the server to allow it to connect
the next request with previous requests in the login process.
This SHOULD be of limited time validity (e.g. 15 minutes from
previous call).
o *methods*: "AuthMethod[]" A list of the supported authentication
methods to continue with authentication. See below for definition
of the *AuthMethod* object.
o *prompt*: "String|null" A message to display in the client to the
user. The client MUST treat this as plain text, but SHOULD
automatically hyperlink any URLs it finds if a system browser is
available.
This is the standard response to an initial request. Note, a server
may return this even if the username is not actually active, to
prevent enumeration. The client should then pick one of the
_methods_ from the list in the response to continue with
authentication (if no methods supported by the client are in the
list, it will not be able to get an access token).
An *AuthMethod* object MUST have a *type* property. This is a
"String" representing the method of authentication. For some types,
there may be other values required on the AuthMethod object in
addition; see the description of types below. The following types
are currently defined, but more may be added in the future. A client
SHOULD offer the user the option to choose any of the method types
returned that the client supports. The client MUST ignore any types
it does not understand:
o "external": The user must do something out-of-band to authorize
the app. The server SHOULD use the _prompt_ property of the
response to tell the user what they need to do. A client that
supports the _external_ authorisation type MUST offer a mechanism
for the user to indicate to the client when they have completed
the out-of-band authentication.
o "oauth": OAuth based authentication. For OAuth integration, see
the docs of the service in question, since every service
implements it slightly differently and the client must register
with the service beforehand to use it. If using this method, an
access token is obtained entirely through the OAuth mechanism from
this point on, and requests will be authenticated as per the OAuth
Jenkins Expires January 17, 2018 [Page 8]
Internet-Draft JMAP July 2017
spec. See the "Refetching URL endpoints" section below for how to
obtain the URL endpoints after successfully authenticating using
OAuth.
o "password": The user must input their current password for the
account.
o "totp": The user must input a TOTP [1] code from a device
registered with the account.
o "yubikeyotp": The user must input a Yubico OTP [2] code from a
Yubikey registered with the account.
o "u2f": The user must sign a challenge using a FIDO U2F [3] key
registered with the account. The AuthMethod object for this type
MUST also have the following properties:
* *appId*: "String" The app id to use.
* *signChallenge*: "String" The challenge to be signed by the U2F
key.
* *registeredKeys*: "RegisteredKey[]" The keys associated with
this user. A *RegisteredKey* object has the following
properties:
* *version*: "String" The U2F protocol version.
* *keyHandle*: "String" The key handle of the registered key.
o "sms": The user must input a one-time code sent via SMS to a phone
number registered with the account. The AuthMethod object for
this type MUST also have the following property:
* *phoneNumbers*: "LoginPhone[]|null" An array of *LoginPhone*
objects, each of which represents a phone registered with the
account. A *LoginPhone* object has the following properties:
+ *id*: "String" The id of the phone. This is used when
asking the server to send a code.
+ *number*: "String" The phone number to display to the user
to remind them which number the SMS will be/was sent to.
This MAY have some characters replaced with an "X" or other
"blanked-out" character if the server does not wish to
disclose the full phone number at this point. e.g. if the
phone registered with the account is "+61 123 456 789", the
server might return "+61 1XX XXX X89" as the number.
Jenkins Expires January 17, 2018 [Page 9]
Internet-Draft JMAP July 2017
+ *isCodeSent*: "Boolean" Has the verification code been sent
to this number yet? The server MAY choose to send the SMS
before the first time this auth option is returned, or may
wait for the user to explicitly request it.
If not using ""oauth"", the user will at some point indicate to the
client to continue authentication (after inputing any required
token/code/password dependent on the auth method chosed). At this
point the client submits a POST request to the same URL as before,
with the body being a single JSON object with the following
properties:
o *loginId*: "String" The _loginId_ the server sent from the
previous request.
o *type*: "String" The type of the method chosen to continue
authentication.
o *value*: "*" The value as appropriate for the given type:
* "external": "null"
* "password"/"totp"/"yubikeyotp"/"sms": "String" - the password/
one-time code.
* "u2f": "SignResponse" - an object with _keyHandle_,
_signatureData_ and _clientData_ "String" properties, as
defined in the U2F spec.
Note: The client SHOULD NOT store any password/code the user has
entered beyond what is required to submit it to the server in this
step.
The server will then return one of the same set of responses as
before, which should be handled the same (for example, if two-factor
authentication is required, a "200" response may be returned again
and TOTP/U2F prompted for).
If the user chooses to authenticate using SMS, they may need to
request the server to send the code to a particular number before
they can submit a code. To do this, the client submits a POST
request to the same URL as before, with the body being a single JSON
object with the following properties:
o *loginId*: "String" The _loginId_ the server sent from the
previous request.
Jenkins Expires January 17, 2018 [Page 10]
Internet-Draft JMAP July 2017
o *sendCodeTo*: "String" The id of the phone number to send the code
to.
The server SHOULD send the code to the given phone if the phone id is
valid. If the code has already been sent, it is server-dependent
whether it is sent again or ignored. The server MUST return one of
the same set of responses as before, which should be handled the same
(in most cases this will be a "200" response identical to before
except that the _isCodeSent_ property for the phone will now be
"true").
2.2.2. 201: Authentication is complete, access token created.
The response body will be a single JSON object with the following
properties.
o *username*: "String" The username that was successfully
authenticated.
o *accessToken*: "String" The secret token to be used by the client
to authenticate all future JMAP requests. The client should keep
this secure, preferably in an OS keychain or the like. Since
tokens should not be reused across devices or clients, the client
SHOULD NOT reveal this token to the user.
o *signingId*: "String" The id to put in the JWT [4] for signed GET
requests (see below). This is used to allow the server to find
the session so it can find the signing key to use to verify the
token. You MUST NOT be able to derive the _accessToken_ or
_signingKey_ from the _signingId_.
o *signingKey*: "String" The secret key to use for signing the JWT
[5] for signed GET requests (see below), encoded as base64url as
specified in ([RFC4648]). The client should keep this secure,
preferably in an OS keychain or the like. Since keys should not
be reused across devices or clients, the client SHOULD NOT reveal
this token to the user.
o *accounts*: "String[Account]" A map of *account id* to Account
object for each account the user has access to. A single access
token may provide access to multiple accounts, for example if
another user is sharing their mail with the logged in user, or if
there is an account that contains data for a group or business.
All data belongs to a single account. With the exception of a few
explicit operations to copy data between accounts, all JMAP
methods take an _accountId_ argument that specifies on which
account the operations are to take place. This argument is always
optional; if not specified, the primary account is used. All ids
Jenkins Expires January 17, 2018 [Page 11]
Internet-Draft JMAP July 2017
(other than Account ids of course) are only unique within their
account. In the event of a severe internal error, a server may
have to reallocate ids or do something else that violates standard
JMAP data constraints. In this situation, the data on the server
is no longer compatible with cached data the client may have from
before. The server MUST treat this as though the account has been
deleted and then recreated with a new account id. Clients will
then be forced to throw away any data with the old account id and
refetch all data from scratch. An *Account* object has the
following properties:
* *name*: "String" A user-friendly string to show when presenting
content from this account, e.g. the email address representing
the owner of the account.
* *isPrimary*: "Boolean" This MUST be true for *at most* one of
the accounts returned. This is to be considered the user's
main or default account by the client. If no account being
returned belongs to the user, or in any other way there is no
appropriate way to determine a default account, then this MAY
be "false" for all accounts.
* *isReadOnly*: "Boolean" This is "true" if the entire account is
read-only.
* *hasDataFor*: "String[]" A list of the data profiles available
in this account. Each future JMAP data types specification
will define a profile name to encompass that set of types.
o *capabilities*: "String[Object]" An object specifying the
capabilities of this server. The keys are URIs, which specify the
specifications supported by the server. The value for each of
these keys is an object that MAY include further information about
the server's capabilities in relation to that spec. The client
MUST ignore any properties it does not understand. The
capabilities object MUST include a property called "{TODO: URI for
this spec}". The value of this property is an object which SHOULD
contain the following information on server capabilities:
* *maxSizeUpload*: "Number" The maximum file size, in bytes, that
the server will accept for a single file upload (for any
purpose).
* *maxConcurrentUpload*: "Number" The maximum number of
concurrent requests the server will accept to the upload
endpoint.
Jenkins Expires January 17, 2018 [Page 12]
Internet-Draft JMAP July 2017
* *maxSizeRequest*: "Number" The maximum size, in bytes, that the
server will accept for a single request to the API endpoint.
* *maxConcurrentRequests*: "Number" The maximum number of
concurrent requests the server will accept to the API endpoint.
* *maxCallsInRequest*: "Number" The maximum number of method
calls the server will accept in a single request to the API
endpoint.
* *maxObjectsInGet*: "Number" The maximum number of obje ts that
the client may request in a single "getFoos" type method call.
* *maxObjectsInSet*: "Number" The maximum number of objects the
client may send to create, update or destroy in a single
"setFoos" type method call.
Future specifications will define their own properties on the
capabilities object.
o *apiUrl*: "String" The URL to use for JMAP API requests.
o *downloadUrl*: "String" The URL endpoint to use when downloading
files (see the Download section of this spec), in [RFC6570] URI
Template (level 1) format. The URL MUST contain variables called
"accountId" and "blobId". The URL SHOULD contain a variable
called "name".
o *uploadUrl*: "String" The URL endpoint to use when uploading files
(see the Upload section of this spec).
o *eventSourceUrl*: "String" The URL to connect to for push events
(see the Push section of this spec).
URLs are returned only after logging in. This allows different URLs
to be used for users located in different geographic datacentres
within the same service.
Note, if authentication is done via IP or mobile subscriber ID or
some similar mechanism, a "201" response MAY be returned in response
to the initial request (with just the username and client info).
2.2.3. 400: Malformed request
The request is of the wrong content type, or does not contain data in
the expected format. The client MUST NOT retry the same request.
There is no content in the response.
Jenkins Expires January 17, 2018 [Page 13]
Internet-Draft JMAP July 2017
2.2.4. 403: Authentication step failed, but client may try again
Returned in response to a continuation request which failed (e.g. the
password entered was not correct, or the out-of-band step was not
completed successfully). The response body will be a single JSON
object with the same properties as the "200" response, and the client
may try again.
2.2.5. 404: Not found
The JMAP authentication server is not available at this address. The
client needs to rediscover the authentication URL. There is no
content in the response.
2.2.6. 410: Restart authentication
The login attempt has failed permanently. This may be due to a
password being incorrect, the login id expiring, or any other reason.
The client MUST restart authentication (go back to sending the
username and client info to the server). There is no content in the
response.
2.2.7. 429: Rate limited
Returned if the server is temporarily blocking this IP/client from
authenticating. This may be due to too many failed password
attempts, or detected username enumeration attempts, or any other
reason. (Legitimate) clients should wait a while then try again.
There is no content in the response.
2.2.8. 500: Internal server error
Something has gone wrong internally, and the server is in a broken
state. Don't automatically retry. There is no content in the
response.
2.2.9. 503: Service unavailable
The server is currently down. Try again later with exponential
backoff. There is no content in the response.
2.3. Refetching URL endpoints
A server MAY (although SHOULD NOT) move end points for any services
other than authentication at any time. If a request to the API/file
upload/event source endpoint returns a "404", the client MUST refetch
the URL endpoints. To do this, it should make an authenticated GET
Jenkins Expires January 17, 2018 [Page 14]
Internet-Draft JMAP July 2017
request to the authentication URL (see below for how to authenticate
requests).
For OAuth logins, this is how the URLs may be fetched initially as
well.
The server MUST respond with one of the following status codes:
2.3.1. 201: Authentication is complete, access token created.
The request was successful. The response will be of type
"application/json" and consists of a single JSON object containing
the following properties:
o *username*: "String" The username that was successfully
authenticated.
o *accounts*: "String[Account]" An object representing the accounts
the user has access to. See the full description above.
o *capabilities*: "String[Object]" An object specifying the
capabilities of this server. See the full description above.
o *apiUrl*: "String" The URL to use for JMAP API requests.
o *downloadUrl*: "String" The URL endpoint to use when downloading
files (see above).
o *uploadUrl*: "String" The URL endpoint to use when uploading files
(see the Upload section of this spec).
o *eventSourceUrl*: "String" The URL to connect to for push events
(see the Push section of this spec).
2.3.2. 403: Restart authentication
The "Authorization" header was missing or did not contain a valid
token. Reauthenticate and then retry the request. There is no
content in the response.
2.3.3. 404: Not found
The JMAP server is no longer here. There is no content in the
response.
Jenkins Expires January 17, 2018 [Page 15]
Internet-Draft JMAP July 2017
2.3.4. 500: Internal server error
Something has gone wrong internally, and the server is in a broken
state. Don't automatically retry. There is no content in the
response.
2.3.5. 503: Service unavailable
The server is currently down. Try again later with exponential
backoff. There is no content in the response.
2.4. Revoking an access token
The validity of an access token is determined by the server. It may
be valid for a limited time only, or expire after a certain time of
inactivity, or be valid indefinitely etc. If an access token
expires, it MUST NOT be resurrected. The client MUST restart the
authentication process to get a new access token.
For OAuth, see the provider's documentation on revoking access
tokens.
Otherwise, a client may revoke an access token at any time by making
an authenticated DELETE HTTP request to the authentication URL (the
one used to get the token in the first place). The response from the
server will be one of the following:
2.4.1. 204: Success
The access token has now been revoked. There is no content in the
response.
2.4.2. 401: Unauthorized
Failed due to missing "Authorization" header, or the "Authorization"
header did not contain a valid access token. As per the HTTP spec,
the response MUST have a "WWW-Authenticate: Bearer" header. There is
no content in the response.
2.5. Authenticating HTTP requests
All HTTP requests other than to the authentication URL must be
authenticated. To do this, the client MUST add an "Authorization"
header to each request.
Once authenticated, the client will have an access token. This is
used with the "Bearer" scheme as specified in [RFC6750] to
authenticate HTTP requests.
Jenkins Expires January 17, 2018 [Page 16]
Internet-Draft JMAP July 2017
For example, if _user@example.com_ successfully logged in and the
client received an _accessToken_ of "abcdef1234567890", to
authenticate requests you would add the following header:
Authorization: Bearer abcdef1234567890
2.5.1. Signed GET requests
Sometimes, particularly in the browser context, authenticating a GET
request using the usual "Authorization" header is not easily
implemented. In such situations, a client may use a signed request
instead.
Instead of the "Authorization" header, a signed request has an
"access_token" query parameter, the value of which is an [RFC7519]
JSON Web Token [6] constructed as follows:
o The algorithm MUST be HMAC SHA-256.
o The JWT MUST contain the following set of claims:
* *iss*: "String" The _signingId_ value returned after
authentication.
* *sub*: "String" The origin + path of the URL being signed,
(i.e. the full URL excluding query parameters).
* *iat*: "Number" The time the client created this JWT, in
seconds since 1970-01-01T00:00:00Z.
o The JWT MUST be signed using the _signingKey_ returned after
authentication as the key.
To verify, a server MUST: * Ensure the algorithm is set to HMAC SHA-
256. * Verify the URL being requested matches that in the _sub_
claim. * Decode the payload and look up the session using the _iss_
claim, ensure it is still valid, and then verify the JWT signature is
valid using the session's _signingKey_.
The server MAY choose to only allow tokens to be valid for a limited
amount of time after the client created it, as determined by the
_iat_ claim.
3. Structured data exchange
The client may make an API request to the server to get or set
structured data. This request consists of an ordered series of
Jenkins Expires January 17, 2018 [Page 17]
Internet-Draft JMAP July 2017
method calls. These are processed by the server, which then returns
an ordered series of responses.
3.1. Making an API request
To make an API request, the client makes an authenticated POST
request to the API URL; see the Authentication section of the spec
for how to discover this URL and how to authenticate requests.
The request MUST have a content type of "application/json" and be
encoded in UTF-8.
The server SHOULD respond with one of the following HTTP response
codes:
3.1.1. 200: OK
The API request was successful. The response will be of type
"application/json" and consists of the response to the API calls, as
described below.
3.1.2. 400: Bad Request
The request was malformed. For example, it may have had the wrong
content type, or have had a JSON object that did not conform to the
API calling structure (see _The structure of an API request_ below).
The client SHOULD NOT retry the same request. There is no content in
the response.
3.1.3. 401: Unauthorized
The "Authorization" header was missing or did not contain a valid
token. Reauthenticate and then retry the request. As per the HTTP
spec, the response MUST have a "WWW-Authenticate" header listing the
available authentication schemes. There is no content in the
response.
3.1.4. 404: Not Found
The API endpoint has moved. See the Authentication section of the
spec for how to rediscover the current URL to use. There is no
content in the response.
3.1.5. 413: Payload Too Large
Returned if the client makes a request with more method calls than
the server is willing to accept in a single request, or if the total
Jenkins Expires January 17, 2018 [Page 18]
Internet-Draft JMAP July 2017
bytes of the request is larger than the max size the server is
willing to accept.
3.1.6. 429: Rate limited
Returned if the client has made too many requests recently, or has
too many concurrent requests currently in progress. Clients SHOULD
wait a while then try again. The response MAY include a "Retry-
After" header indicating how long to wait before making a new
request.
3.1.7. 500: Internal Server Error
Something has gone wrong internally, and the server is in a broken
state. Don't automatically retry. There is no content in the
response.
3.1.8. 503: Service Unavailable
The server is currently down. Try again later with exponential
backoff. There is no content in the response.
3.2. The structure of an API request
The client initiates an API request by sending the server a JSON
array. Each element in this array is another array representing a
method invocation on the server. The server will process the method
calls and return a response consisting of an array in the same
format. Each method call always contains three elements:
1. The *name* of the method to call, or the name of the response
from the server. This is a "String".
2. An "Object" containing _named_ *arguments* for that method or
response.
3. A *client id*: an arbitrary "String" to be echoed back with the
responses emitted by that method call (as we'll see lower down, a
method may return 1 or more responses, as some methods make
implicit calls to other ones).
Example query:
[
["method1", {"arg1": "arg1data", "arg2": "arg2data"}, "#1"],
["method2", {"arg1": "arg1data"}, "#2"],
["method3", {}, "#3"]
]
Jenkins Expires January 17, 2018 [Page 19]
Internet-Draft JMAP July 2017
The method calls MUST be processed sequentially, in order. Each API
request (which, as shown, may contain multiple method calls) receives
a JSON response in exactly the same format. The output of the
methods MUST be added to the array in the same order as the methods
are processed.
Example response:
[
["responseFromMethod1", {"arg1": 3, "arg2": "foo"}, "#1"],
["responseFromMethod2", {"isBlah": true}, "#2"],
["anotherResponseFromMethod2", {
"data": 10,
"yetmoredata": "Hello"
}, "#2"],
["aResponseFromMethod3", {}, "#3"]
]
3.3. Errors
If the data sent as an API request is not valid JSON or does not
match the structure above, an error will be returned at the transport
level. For example, when using JMAP over HTTP, a "400 Bad Request"
error will be returned at the HTTP level.
Possible errors for each method are specified in the method
descriptions. If a method encounters an error, the appropriate
"error" response MUST be inserted at the current point in the output
array and, unless otherwise specified, further processing MUST NOT
happen within that method call.
Any further method calls in the request MUST then be processed as
normal.
An "error" response looks like this:
["error", {
type: "unknownMethod"
}, "client-id"]
The response name is "error", and it has a type property as specified
in the method description. Other properties may be present with
further information; these are detailed in the method descriptions
where appropriate.
Any method MAY return an error of type "serverError" if an unexpected
or unknown error occurs during the processing of that call. The
state of the server after such an error is undefined.
Jenkins Expires January 17, 2018 [Page 20]
Internet-Draft JMAP July 2017
If an unknown method is called, an "unknownMethod" error (this is the
type shown in the example above) MUST be inserted and then the next
method call MUST be processed as normal.
If an unknown argument or invalid arguments (wrong type, or in
violation of other specified constraints) are supplied to a method,
an "invalidArguments" error MUST be inserted and then the next method
call MUST be processed as normal.
3.4. Vendor-specific extensions
Individual services will have custom features they wish to expose
over JMAP. This may take the form of extra datatypes and/or methods
not in the spec, or extra arguments to JMAP methods, or extra
properties on existing data types (which may also appear in arguments
to methods that take property names). To ensure compatibility with
clients that don't know about a specific custom extension, and for
compatibility with future versions of JMAP, the server MUST ONLY
expose these extensions if the client explicitly opts in. Without
opt-in, the server MUST follow the spec and reject anything that does
not conform to it as specified.
3.5. Security
As always, the server must be strict about data received from the
client. Arguments need to be checked for validity; a malicious user
could attempt to find an exploit through the API. In case of invalid
arguments (unknown/insufficient/wrong type for data etc.) the method
MUST return an "invalidArguments" error and terminate.
3.6. Concurrency
To ensure the client always sees a consistent view of the data, the
state accessed by a method call MUST NOT change during the execution
of the method, except due to actions by the method call itself. The
state MAY change in-between method calls (even within a single API
request).
3.7. The Number datatype
The JSON datatypes are limited to those found in JavaScript. A
"Number" in JavaScript is represented as a signed double (64-bit
floating point). However, except where explicitly specified, all
numbers used in this API are unsigned integers <= 2^53 (the maximum
integer that may be reliably stored in a double). This implicitly
limits the maximum length of message lists in queries and the like.
Jenkins Expires January 17, 2018 [Page 21]
Internet-Draft JMAP July 2017
3.8. The Date datatypes
Where a JMAP API specifies "Date" as a type, it means a string in
[RFC3339] _date-time_ format, with the _time-offset_ component always
"Z" (i.e. the date-time MUST be in UTC time) and _time-secfrac_
always omitted. The "T" and "Z" MUST always be upper-case. For
example, ""2014-10-30T14:12:00Z"".
3.9. Use of null
Unless otherwise specified, a missing property in the arguments
object of a request (from the client), or a response (from the
server) MUST be intepreted exactly the same as that property having
the value "null".
Unless otherwise specified, a missing property in a data object MUST
be interpreted in the following ways: - In the response to a
_getFoos_ style call, or when *creating* an object in a _setFoos_
style call, a missing property MUST be interpreted as though it had
the default value for that type, or "null" if no default is
specified. - When *updating* an object in a _setFoos_ style call, a
missing property MUST be interpreted as the existing value for that
property (i.e. don't update it).
For network efficiency, when fetching the server and client may make
use of the above and omit properties which have the default value for
the data type.
3.10. CRUD methods
JMAP provides a uniform interface for creating, retrieving, updating
and deleting various types of objects. For a "Foo" data type,
records of that type would be fetched via a "getFoos" call and
modified via a "setFoos" call. Delta updates may be fetched via a
"getFooUpdates" call. These methods all follow a standard format as
described below.
3.10.1. getFoos
Objects of type *Foo* are fetched via a call to _getFoos_. Methods
with a name starting with "get" MUST NOT alter state on the server.
This method may take some or all of the following arguments; see the
definition of the data type in question. However, if one of the
following arguments is available, it will behave exactly as specified
below.
Jenkins Expires January 17, 2018 [Page 22]
Internet-Draft JMAP July 2017
o *accountId*: "String|null" The id of the Account to use. If
"null", the primary account is used.
o *ids*: "String[]|null" The ids of the Foo objects to return. If
"null" then *all* records of the data type are returned, if this
is supported for that data type.
o *properties*: "String[]|null" If supplied, only the properties
listed in the array are returned for each Foo object. If "null",
all properties of the object are returned. The id of the object
is *always* returned, even if not explicitly requested.
The response to "getFoos" is called "foos". It has the following
arguments:
o *accountId*: "String" The id of the account used for the call.
o *state*: "String" A string representing the state on the server
for *all* the data of this type. If the data changes, this string
will change. It is used to get delta updates, if supported for
the type.
o *list*: "Foo[]" An array of the Foo objects requested. This is
the *empty array* if no objects were found, or if the _ids_
argument passed in was also the empty array.
o *notFound*: "String[]|null" This array contains the ids passed to
the method for records that do not exist. This property is "null"
if all requested ids were found, or if the _ids_ argument passed
in was either "null" or the empty array.
The following error may be returned instead of the "foos" response:
"accountNotFound": Returned if an _accountId_ was explicitly included
with the request, but it does not correspond to a valid account.
"accountNotSupportedByMethod": Returned if the _accountId_ given
corresponds to a valid account, but the account does not support this
data type.
"requestTooLarge": Returned if the number of _ids_ requested by the
client exceeds the maximum number the server is willing to process in
a single method call.
"invalidArguments": Returned if one of the arguments is of the wrong
type, or otherwise invalid. A "description" property MAY be present
on the response object to help debug with an explanation of what the
problem was.
Jenkins Expires January 17, 2018 [Page 23]
Internet-Draft JMAP July 2017
3.10.2. getFooUpdates
When the state of the set of Foo records changes on the server
(whether due to creation, updates or deletion), the _state_ property
of the _foos_ response will change. The _getFooUpdates_ call allows
a client to efficiently update the state of any its Foo cache to
match the new state on the server. It takes the following arguments:
o *accountId*: "String|null" The id of the Account to use. If
"null", the primary account is used.
o *sinceState*: "String" The current state of the client. This is
the string that was returned as the _state_ argument in the _foos_
response. The server will return the changes made since this
state.
o *maxChanges*: "Number|null" The maximum number of Foo ids to
return in the response. The server MAY choose to return fewer
than this value, but MUST NOT return more. If not given by the
client, the server may choose how many to return. If supplied by
the client, the value MUST be a positive integer greater than 0.
If a value outside of this range is given, the server MUST reject
the call with an "invalidArguments" error.
o *fetchRecords*: "Boolean|null" If "true", immediately after
outputting the _fooUpdates_ response, the server will make an
implicit call to _getFoos_ with the _changed_ property of the
response as the _ids_ argument. If "false" or "null", no implicit
call will be made.
o *fetchRecordProperties*: "String[]|null" If the _getFoos_ method
takes a _properties_ argument, this argument is passed through on
implicit calls (see the _fetchRecords_ argument).
The response to _getFooUpdates_ is called _fooUpdates_. It has the
following arguments:
o *accountId*: "String" The id of the account used for the call.
o *oldState*: "String" This is the _sinceState_ argument echoed
back; the state from which the server is returning changes.
o *newState*: "String" This is the state the client will be in after
applying the set of changes to the old state.
o *hasMoreUpdates*: "Boolean" If "true", the client may call
_getFooUpdates_ again with the _newState_ returned to get further
updates. If "false", _newState_ is the current server state.
Jenkins Expires January 17, 2018 [Page 24]
Internet-Draft JMAP July 2017
o *changed*: "String[]" An array of Foo ids for records which have
been created or changed but not destroyed since the oldState.
o *removed*: "String[]" An array of Foo ids for records which have
been destroyed since the old state.
The _maxChanges_ argument (and _hasMoreUpdates_ response argument) is
available for data types with potentially large amounts of data (i.e.
those for which there is a _getFooList_ method available for loading
the data in pages). If a _maxChanges_ is supplied, or set
automatically by the server, the server must try to limit the number
of ids across _changed_ and _removed_ to the number given. If there
are more changes than this between the client's state and the current
server state, the update returned MUST take the client to an
intermediate state, from which the client can continue to call
_getFooUpdates_ until it is fully up to date. The server MUST NOT
return more ids than the _maxChanges_ total. If the server is unable
to calculate a suitable intermediate state, it MUST return a
"cannotCalculateChanges" error.
If a Foo record has been modified AND deleted since the oldState, the
server SHOULD just return the id in the _removed_ response, but MAY
return it in the changed response as well. If a Foo record has been
created AND deleted since the oldState, the server SHOULD remove the
Foo id from the response entirely, but MAY include it in the
_removed_ response.
The following errors may be returned instead of the _fooUpdates_
response:
"accountNotFound": Returned if an _accountId_ was explicitly included
with the request, but it does not correspond to a valid account.
"accountNotSupportedByMethod": Returned if the _accountId_ given
corresponds to a valid account, but the account does not support this
data type.
"invalidArguments": Returned if the request does not include one of
the required arguments, or one of the arguments is of the wrong type,
or otherwise invalid. A _description_ property MAY be present on the
response object to help debug with an explanation of what the problem
was.
"cannotCalculateChanges": Returned if the server cannot calculate the
changes from the state string given by the client. Usually due to
the client's state being too old, or the server being unable to
produce an update to an intermediate state when there are too many
updates. The client MUST invalidate its Foo cache.
Jenkins Expires January 17, 2018 [Page 25]
Internet-Draft JMAP July 2017
3.10.3. setFoos
Modifying the state of Foo objects on the server is done via the
_setFoos_ method. This encompasses creating, updating and destroying
Foo records. This has two benefits:
1. It allows the server to sort out ordering and dependencies that
may exist if doing multiple operations at once (for example to
ensure there is always a minimum number of a certain record
type).
2. A single call can make all the changes you want to a particular
type. If the client wants to use _ifInState_ to guard its
changes, it is only possible for it to make one call that
modifies any particular type per request, since it will need the
new state following that call to make the next modification.
The _setFoos_ method takes the following arguments:
o *accountId*: "String|null" The id of the Account to use. If
"null", the primary account is used.
o *ifInState*: "String|null" This is a state string as returned by
the _getFoos_ method. If supplied, the string must match the
current state, otherwise the method will be aborted and a
"stateMismatch" error returned. If "null", any changes will be
applied to the current state.
o *create*: "String[Foo]|null" A map of _creation id_ (an arbitrary
string set by the client) to Foo objects (containing all
properties except the id, unless otherwise stated in the specific
documentation of the data type). If "null", no objects will be
created.
o *update*: "String[Foo]|null" A map of id to Foo objects. The
object may omit any property; only properties that have changed
need be included. If "null", no objects will be updated.
o *destroy*: "String[]|null" A list of ids for Foo objects to
permanently delete. If "null", no objects will be deleted.
Each create, update or destroy is considered an atomic unit. It is
permissible for the server to commit some of the changes but not
others, however it is not permissible to only commit part of an
update to a single record (e.g. update a _name_ property but not a
_count_ property, if both are supplied in the update object).
Jenkins Expires January 17, 2018 [Page 26]
Internet-Draft JMAP July 2017
If a create, update or destroy is rejected, the appropriate error
MUST be added to the notCreated/notUpdated/notDestroyed property of
the response and the server MUST continue to the next create/update/
destroy. It does not terminate the method.
If an id given cannot be found, the update or destroy MUST be
rejected with a "notFound" set error.
Some record objects may hold references to others (foreign keys).
When records are created or modified, they may reference other
records being created _in the same API request_ by using the creation
id prefixed with a "#". The order of the method calls in the request
by the client MUST be such that the record being referenced is
created in the same or an earlier call. The server thus never has to
look ahead. Instead, while processing a request (a series of method
calls), the server MUST keep a simple map for the duration of the
request of creation id to record id for each newly created record, so
it can substitute in the correct value if necessary in later method
calls. The type
Creation ids are scoped by type; a separate "creation id -> id" map
MUST be kept for each type. Foreign key references are always for a
particular record type, so use of the same creation key in two
different types cannot cause any ambiguity. Creation ids sent by the
client SHOULD be unique within the single API request for a
particular data type. If a creation id is reused for the same type,
the server MUST map the creation id to the most recently created item
with that id.
The response to _setFoos_ is called _foosSet_. It has the following
arguments:
o *accountId*: "String" The id of the account used for the call.
o *oldState*: "String|null" The state string that would have been
returned by _getFoos_ before making the requested changes, or
"null" if the server doesn't know what the previous state string
was.
o *newState*: "String" The state string that will now be returned by
_getFoos_.
o *created*: "String[Foo]" A map of the creation id to an object
containing any *server-assigned* properties of the Foo object
(including the id) for all successfully created records.
o *updated*: "String[Foo|null]" The _keys_ in this map are the ids
of all Foos that were successfully updated. Some data types may
Jenkins Expires January 17, 2018 [Page 27]
Internet-Draft JMAP July 2017
have properties which can only be determined by the server, and
which may change as a result of the other properties being updated
by the client. In this case, the _value_ for the corresponding id
in the map is an object containing the updated value of each
property the *server changed* on the record. Otherwise (if no
properties changed on the server other than those explicitly
updated by the client), the value is "null".
o *destroyed*: "String[]" A list of Foo ids for records that were
successfully destroyed.
o *notCreated*: "String[SetError]" A map of creation id to a
SetError object for each record that failed to be created. The
possible errors are defined in the description of the method for
specific data types.
o *notUpdated*: "String[SetError]" A map of Foo id to a SetError
object for each record that failed to be updated. The possible
errors are defined in the description of the method for specific
data types.
o *notDestroyed*: "String[SetError]" A map of Foo id to a SetError
object for each record that failed to be destroyed. The possible
errors are defined in the description of the method for specific
data types.
A *SetError* object has the following properties:
o *type*: "String" The type of error.
o *description*: "String|null" A description of the error to display
to the user.
Other properties may also be present on the object, as described in
the relevant methods.
The following errors may be returned instead of the "foosSet"
response:
"accountNotFound": Returned if an _accountId_ was explicitly included
with the request, but it does not correspond to a valid account.
"accountNotSupportedByMethod": Returned if the _accountId_ given
corresponds to a valid account, but the account does not support this
data type.
"accountReadOnly": Returned if the account has isReadOnly == true.
Jenkins Expires January 17, 2018 [Page 28]
Internet-Draft JMAP July 2017
"requestTooLarge": Returned if the total number of objects to create,
update or destroy exceeds the maximum number the server is willing to
process in a single method call.
"invalidArguments": Returned if one of the arguments is of the wrong
type, or otherwise invalid. A "description" property MAY be present
on the response object to help debug with an explanation of what the
problem was.
"stateMismatch": Returned if an "ifInState" argument was supplied and
it does not match the current state.
3.11. Querying data
For data sets where the total amount of data is expected to be very
small, clients can just fetch the complete set of data and then do
any sorting/filtering locally. However, for large data sets (e.g.
multi-gigabyte mailboxes), the client needs to be able to perform a
query on the server for the data type.
3.11.1. getFooList
A query on the set of Foos in an account is made by calling
_getFooList_. This takes a number of arguments to determine which
records to include, how they should be sorted, and which part of the
result should be returned (the full list may be _very_ long). The
result is returned as a list of Foo ids. Optionally, the records
themselves may be fetched at the same time.
A call to _getFooList_ takes the following arguments:
o *filter*: "FilterCondition" Determines the set of Foos returned in
the results. This is an "object", whose allowed properties and
semantics depend on the data type.
o *sort*: "String[]|null" Lists the properties to compare between
two Foo records to determine which comes first in the sort. If
two Foo records have an identical value for the first property,
the next property will be considered and so on. If all properties
are the same (this includes the case where an empty array or
"null" is given as the _sort_ argument), the sort order is server-
dependent, but MUST be stable between calls to "getFooList".
Following each property name there MUST be a space and then either
the string "asc" or "desc" to specify ascending or descending sort
for that property. e.g. "[ "date desc", "name asc" ]"
o *position*: "Number|null" The 0-based index of the first id in the
full list of results to return, presumed "0" if "null". If a
Jenkins Expires January 17, 2018 [Page 29]
Internet-Draft JMAP July 2017
negative value is given, the call MUST be rejected with an
"invalidArguments" error.
o *limit*: "Number|null" The maximum number of results to return.
If "null", no limit presumed. The server MAY choose to enforce a
maximum "limit" argument. In this case, if a greater value is
given (or if it is "null"), the limit should be clamped to the
maximum; since the total number of results in the list is
returned, the client can determine if it has received all the
results. If a negative value is given, the call MUST be rejected
with an "invalidArguments" error.
o *fetchFoos*: "Boolean|null" If "true" then after outputting a
_fooList_ response, an implicit call will be made to _getFoos_
with the "fooIds" array in the response as the _ids_ argument. If
"false" or "null", no implicit call will be made.
o *fetchFooProperties*: "String[]|null" The list of properties to
fetch on any fetched foos. See _getFoos_ for a full description.
The response to a call to _getFooList_ is called _fooList_. It has
the following arguments:
o *filter*: "FilterCondition" The filter of the foo list. Echoed
back from the call.
o *sort*: "String[]|null" A list of Foo property names used to sort
by. Echoed back from the call.
o *state*: "String" A string encoding the current state on the
server. This string will change if the results of the Foo list
MAY have changed (for example, there has been a change to the
state of the set of Foos; it does not guarantee that anything in
the list has changed). It may be passed to _getFooListUpdates_ to
efficiently get the set of changes from the client's current
state. Should a client receive back a response with a different
state string to a previous call, it MUST either throw away the
currently cached list and fetch it again (note, this does not
require fetching the foos again, just the list of ids) or, call
_getFooListUpdates_ to get the delta difference.
o *canCalculateUpdates*: "Boolean" This is "true" if the server
supports calling _getFooListUpdates_ with these "filter"/"sort"
parameters. Note, this does not guarantee that the
_getFooListUpdates_ call will succeed, as it may only be possible
for a limited time afterwards due to server internal
implementation details.
Jenkins Expires January 17, 2018 [Page 30]
Internet-Draft JMAP July 2017
o *position*: "Number" The 0-based index of the first result in the
"fooIds" array within the complete list of results.
o *total*: "Number" The total number of foos in the foos list (given
the _filter_).
o *fooIds*: "String[]" The list of Foo ids for each foo in the list
after filtering and sorting, starting at the index given by the
_position_ argument of this response, and continuing until it hits
the end of the list or reaches the "limit" number of ids.
The following errors may be returned instead of the "fooList"
response:
"accountNotFound": Returned if an _accountId_ was explicitly included
with the request, but it does not correspond to a valid account.
"accountNotSupportedByMethod": Returned if the _accountId_ given
corresponds to a valid account, but the account does not support this
data type.
"invalidArguments": Returned if the request does not include one of
the required arguments, or one of the arguments is of the wrong type,
or otherwise invalid. A "description" property MAY be present on the
response object to help debug with an explanation of what the problem
was.
3.11.2. getFooListUpdates
The "getFooListUpdates" call allows a client to efficiently update
the state of any cached foo list to match the new state on the
server. It takes the following arguments:
o *filter*: "FilterCondition" The filter argument that was used with
_getFooList_.
o *sort*: "String[]|null" The sort argument that was used with
_getFooList_.
o *sinceState*: "String" The current state of the client. This is
the string that was returned as the _state_ argument in the
_fooList_ response. The server will return the changes made since
this state.
o *maxChanges*: "Number|null" The maximum number of changes to
return in the response. See below for a more detailed
description.
Jenkins Expires January 17, 2018 [Page 31]
Internet-Draft JMAP July 2017
The response to _getFooListUpdates_ is called _fooListUpdates_ It has
the following arguments:
o *filter*: "FilterCondition" The filter of the foo list. Echoed
back from the call.
o *sort*: "String[]|null" A list of Foo property names used to sort
by. Echoed back from the call.
o *oldState*: "String" This is the "sinceState" argument echoed
back; the state from which the server is returning changes.
o *newState*: "String" This is the state the client will be in after
applying the set of changes to the old state.
o *total*: "Number" The total number of foos in the current foo list
(given the _filter_).
o *removed*: "String[]" The _fooId_ for every foo that was in the
list in the old state and is not in the list in the new state. If
the server cannot calculate this exactly, the server MAY return
extra foos in addition that MAY have been in the old list but are
not in the new list. If the _filter_ or _sort_ includes a mutable
property, the server MUST include all foos in the current list for
which this property MAY have changed.
o *added*: "AddedItem[]" The fooId and index in the list (in the new
state) for every foo that has been added to the list since the old
state AND every foo in the current list that was included in the
_removed_ array (due to a filter or sort based upon a mutable
property). The array MUST be sorted in order of index, lowest
index first.
An *AddedItem* object has the following properties:
o *fooId*: "String"
o *index*: "Number"
The result of this should be that if the client has a cached sparse
array of foo ids in the list in the old state:
fooIds = [ "id1", "id2", null, null, "id3", "id4", null, null, null ]
then if it *splices out* all foos in the removed array:
removed = [ "id2", ... ];
fooIds => [ "id1", null, null, "id3", "id4", null, null, null ]
Jenkins Expires January 17, 2018 [Page 32]
Internet-Draft JMAP July 2017
and *splices in* (in order) all of the foos in the added array:
added = [{ fooId: "id5", index: 0, ... }];
fooIds => [ "id5", "id1", null, null, "id3", "id4", null, null, null ]
then the foo list will now be in the new state.
The following errors may be returned instead of the "fooListUpdates"
response:
"accountNotFound": Returned if an _accountId_ was explicitly included
with the request, but it does not correspond to a valid account.
"accountNotSupportedByMethod": Returned if the _accountId_ given
corresponds to a valid account, but the account does not support this
data type.
"invalidArguments": Returned if the request does not include one of
the required arguments, or one of the arguments is of the wrong type,
or otherwise invalid. A _description_ property MAY be present on the
response object to help debug with an explanation of what the problem
was.
"tooManyChanges": Returned if there are more changes the the client's
_maxChanges_ argument. Each item in the removed or added array is
considered as one change. The client may retry with a higher max
changes or invalidate its cache of the foo list.
"cannotCalculateChanges": Returned if the server cannot calculate the
changes from the state string given by the client. Usually due to
the client's state being too old. The client MUST invalidate its
cache of the foo list.
4. Downloading binary data
Binary data is referenced by a _blobId_ in JMAP. A blob id does not
have a name inherent to it, but this is normally given in the same
object that contains the blob id.
After completing authentication, the client will receive a
_downloadUrl_ as part of the response. This is in [RFC6570] URI
Template (level 1) format. The URL MUST contain variables called
"accountId" and "blobId". The URL SHOULD contain a variable called
"name".
The client may use this template in combination with an accountId and
blobId to download any binary data (files) referenced by other
objects. Since a blob is not associated with a particular name, the
Jenkins Expires January 17, 2018 [Page 33]
Internet-Draft JMAP July 2017
template SHOULD allow a name to be substituted in as well; the server
will return this as the filename if it sets a "Content-Disposition"
header.
To download the data the client MUST make an authenticated GET
request to the download URL with the appropriate variables
substituted in, and then follow any redirects. The client SHOULD
send an "Accept" header with the content type they would like the
server to return for the file.
In situations where it's not easy to authenticate the download
request (e.g.: when downloading a file through a link in a HTML
document), the client MAY use a signed GET request (see the
authentication chapter for how to issue a signed request). Instead
of specifying an "Accept" header, the client SHOULD add an "accept"
query parameter to the signed URL, with the value being the content
type to use for the response.
After following redirects, the server MUST return one of the
following responses to a request to the download URL:
4.1. 200: OK
Request successful. The binary data is returned. The "Content-Type"
header SHOULD be set to the type as requested in the "Accept" header
by the client, or "application/octet-stream" if unknown and no
"Accept" header given.
4.2. 401: Unauthorized
The "Authorization" header was missing or did not contain a valid
token and there was no "access_token" query parameter, or it did not
contain a valid token. Reauthenticate and then retry the request.
As per the HTTP spec, the response MUST have a "WWW-Authenticate"
header listing the available authentication schemes.
The server MAY return an HTML page response, which clients MAY show
to the user. This is primarily for when the URL is passed off to the
browser, and the JMAP client may not see the actual response.
4.3. 404: Not Found
The file was not found at this address.
Jenkins Expires January 17, 2018 [Page 34]
Internet-Draft JMAP July 2017
4.4. 503: Service Unavailable
The server is currently down. The client should try again later with
exponential backoff. There is no content in the response.
5. Uploading binary data
There is a single endpoint which handles all file uploads, regardless
of what they are to be used for. To upload a file, the client
submits a POST request to the file upload endpoint (see the
authentication section for information on how to obtain this URL).
The Content-Type MUST be correctly set for the type of the file being
uploaded. The request MUST be authenticated as per any HTTP request.
The request MAY include an "X-JMAP-AccountId" header, with the value
being the account to use for the request. Otherwise, the default
account will be used.
The server will respond with one of the following HTTP response
codes:
5.1. 201: File uploaded successfully
The content of the response is a single JSON object with the
following properties:
o *accountId*: "String" The id of the account used for the call.
o *blobId*: "String", The id representing the binary data uploaded.
The data for this id is immutable. The id _only_ refers to the
binary data, not any metadata.
o *type*: "String" The content type of the file.
o *size*: "Number" The size of the file in bytes.
o *expires*: "Date" The date the file will be deleted from temporary
storage if not referenced by another object, e.g. used in a draft.
Once the file has been used, for example attached to a draft message,
the file will no longer expire, and is instead guaranteed to exist
while at least one other object references it. Once no other object
references it, the server MAY immediately delete the file at any
time. It MUST NOT delete the file during the method call which
removed the last reference, so that if there is a create and a delete
within the same call that both reference the file, this always works.
If uploading a file would take the user over quota, the server SHOULD
delete previously uploaded (but unused) files before their expiry
Jenkins Expires January 17, 2018 [Page 35]
Internet-Draft JMAP July 2017
time. This means a client does not have to explicitly delete unused
temporary files (indeed, there is no way for it to do so).
If identical binary content is uploaded, the same _blobId_ SHOULD be
returned.
The server MUST return one of the following responses to a request to
the upload URL:
5.2. 400: Bad request
The request was malformed (this includes the case where an "X-JMAP-
AccountId" header is sent with a value that does not exist). The
client SHOULD NOT retry the same request. There is no content in the
response.
5.3. 401: Unauthorized
The "Authorization" header was missing or did not contain a valid
token. Reauthenticate and then retry the request. As per the HTTP
spec, the response MUST have a "WWW-Authenticate" header listing the
available authentication schemes. There is no content in the
response.
5.4. 404: Not Found
The upload endpoint has moved. See the Authentication section of the
spec for how to rediscover the current URL to use. There is no
content in the response.
5.5. 413: Request Entity Too Large
The file is larger than the maximum size the server is willing to
accept for a single file. The client SHOULD NOT retry uploading the
same file. There is no content in the response. The client may
discover the maximum size the server is prepared to accept by
inspecting the server _capabilities_ object, returned with the
successful authentication response.
5.6. 415: Unsupported Media Type
The server MAY choose to not allow certain content types to be
uploaded, such as executable files. This error response is returned
if an unacceptable type is uploaded. The client SHOULD NOT retry
uploading the same file. There is no content in the response.
Jenkins Expires January 17, 2018 [Page 36]
Internet-Draft JMAP July 2017
5.6.1. 429: Rate limited
Returned if the client has made too many upload requests recently, or
has too many concurrent uploads currently in progress. Clients
SHOULD wait a while then try again. The response MAY include a
"Retry-After" header indicating how long to wait before making a new
request.
5.7. 503: Service Unavailable
The server is currently down. The client should try again later with
exponential backoff. There is no content in the response.
6. Push
Any modern email client should be able to update instantly whenever
the data on the server is changed by another client or message
delivery. Push notifications in JMAP occur out-of-band (i.e. not
over the same connection as API exchanges) so that they can make use
of efficient native push mechanisms on different platforms.
The general model for push is simple and does not send any sensitive
data over the push channel, making it suitable for use with less
trusted 3rd party intermediaries. The format allows multiple changes
to be coalesced into a single push update, and the frequency of
pushes to be rate limited by the server. It doesn't matter if some
push events are dropped before they reach the client; it will still
get all changes next time it syncs.
When something changes on the server, the server pushes a small JSON
object to the client with the following property:
o *changed*: "String[ChangedStates]" A map of _account id_ to an
object encoding the state of data types which have changed for
that account since the last push event, for each of the accounts
to which the user has access and for which something has changed.
A *ChangedStates* object is a map. The keys are the plural type name
"Foos" (e.g. "Mailboxes" or "Messages"), and the value is the
_state_ property that would currently be returned by a call to
_getFoos_.
Upon receiving this data, the client can compare the new state
strings with its current values to see whether it has the current
data for these types. The actual changes can then be efficiently
fetched in a single standard API request (using the _getFooUpdates_
type methods).
Jenkins Expires January 17, 2018 [Page 37]
Internet-Draft JMAP July 2017
6.1. Event Source
There are two mechanisms by which the client can receive the push
events. The first is directly via a "text/event-stream" resource, as
described in . This is
essentially a long running HTTP request down which the server can
push data. When a change occurs, the server MUST push an event
called *state* to any connected clients.
The server MAY also set a new "Last-Event-Id" that encodes the entire
server state visible to the user. When a new connection is made to
the event-source endpoint, the server can then work out whether the
client has missed some changes which it should send immediately.
The server MUST also send an event called *ping* with an empty object
as the data if a maximum of 5 minutes has elapsed since the previous
event. This MUST NOT set a new "Last-Event-Id". A client may detect
the absence of these to determine that the HTTP connection has been
dropped somewhere along the route and so it needs to re-establish the
connection.
Refer to the Authentication section of this spec for details on how
to get the URL for the event-source endpoint. The request must be
authenticated using an "Authorization" header like any HTTP request.
A client MAY hold open multiple connections to the event-source,
although it SHOULD try to use a single connection for efficiency.
6.2. Web hook
The second push mechanism is to register a callback URL to which the
JMAP server will make an HTTPS POST request whenever the event
occurs. The request MUST have a content type of "application/json"
and contain the same UTF-8 JSON encoded object as described above as
the body.
The JMAP server MUST also set the following headers in the POST
request: - "X-JMAP-EventType: state" - "X-JMAP-User: ${username}"
where "${username}" is the username of the authenticated user for
which the push event occurred.
The JMAP server MUST follow any redirects. If the final response
code from the server is "2xx", the callback is considered a success.
If the response code is "503" (Service Unavailable), the JMAP server
MAY try again later (but may also just drop the event). If the
response code is "429" (Too Many Requests) the JMAP server SHOULD
attempt to reduce the frequency of pushes to that URL. Any other
response code MUST be considered a *permanent failure* and the
Jenkins Expires January 17, 2018 [Page 38]
Internet-Draft JMAP July 2017
callback should be deregistered (not tried again even for future
events unless explicitly re-registered by the client).
The URL set by the client MUST use the HTTPS protocol and SHOULD
encode within it a unique token that can be verified by the server to
know that the request comes from the JMAP server the authenticated
client connected to.
The callback is tied to the access token used to create it. Should
the access token expire or be revoked, the callback MUST be removed
by the JMAP server. The client MUST re-register the callback after
reauthenticating to resume callbacks.
Each session may only have a single callback URL registered. It can
be set or retrieved using the following API calls.
6.2.1. setPushCallback
To set the web hook, make a call to _setPushCallback_. It takes the
following argument:
o *callback*: "String|null" The (HTTPS) URL the JMAP server should
POST events to. This will replace any previously set URL. Set to
"null" to just remove any previously set callback URL.
The response to _setPushCallback_ is called _pushCallbackSet_. It has
the following argument:
o *callback*: "String|null" Echoed back from the call.
The following error may be returned instead of the _mailboxesSet_
response:
"invalidUrl": Returned if the URL does not begin with "https://", or
is otherwise syntactically invalid or does not resolve.
6.2.2. getPushCallback
To check the currently set callback URL (if any), make a call to
_getPushCallback_. It does not take any arguments. The response to
_getPushCallback_ is called "pushCallback". It has a single
argument:
o *callback*: "String|null" The URL the JMAP server is currently
posting push events to, or "null" if none.
Jenkins Expires January 17, 2018 [Page 39]
Internet-Draft JMAP July 2017
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
.
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
2003, .
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
.
[RFC5785] Nottingham, M. and E. Hammer-Lahav, "Defining Well-Known
Uniform Resource Identifiers (URIs)", RFC 5785,
DOI 10.17487/RFC5785, April 2010,
.
[RFC6186] Daboo, C., "Use of SRV Records for Locating Email
Submission/Access Services", RFC 6186,
DOI 10.17487/RFC6186, March 2011,
.
[RFC6570] Gregorio, J., Fielding, R., Hadley, M., Nottingham, M.,
and D. Orchard, "URI Template", RFC 6570,
DOI 10.17487/RFC6570, March 2012,
.
[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
Framework: Bearer Token Usage", RFC 6750,
DOI 10.17487/RFC6750, October 2012,
.
[RFC6764] Daboo, C., "Locating Services for Calendaring Extensions
to WebDAV (CalDAV) and vCard Extensions to WebDAV
(CardDAV)", RFC 6764, DOI 10.17487/RFC6764, February 2013,
.
Jenkins Expires January 17, 2018 [Page 40]
Internet-Draft JMAP July 2017
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, .
[RFC7493] Bray, T., Ed., "The I-JSON Message Format", RFC 7493,
DOI 10.17487/RFC7493, March 2015,
.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
.
7.2. URIs
[1] https://tools.ietf.org/html/rfc6238
[2] https://developers.yubico.com/OTP/
[3] https://fidoalliance.org/specifications/download/
[4] https://tools.ietf.org/html/rfc7519
[5] https://tools.ietf.org/html/rfc7519
[6] https://jwt.io/
Author's Address
Neil Jenkins
FastMail
Level 1, 91 William St
Melbourne VIC 3000
Australia
Email: neilj@fastmail.com
URI: https://www.fastmail.com
Jenkins Expires January 17, 2018 [Page 41]