7Internet Engineering Task Force (IETF) N. Jenkins
8Request for Comments: 8620 Fastmail
9Category: Standards Track C. Newman
14 The JSON Meta Application Protocol (JMAP)
18 This document specifies a protocol for clients to efficiently query,
19 fetch, and modify JSON-based data objects, with support for push
20 notification of changes and fast resynchronisation and for out-of-
21 band binary data upload/download.
25 This is an Internet Standards Track document.
27 This document is a product of the Internet Engineering Task Force
28 (IETF). It represents the consensus of the IETF community. It has
29 received public review and has been approved for publication by the
30 Internet Engineering Steering Group (IESG). Further information on
31 Internet Standards is available in Section 2 of RFC 7841.
33 Information about the current status of this document, any errata,
34 and how to provide feedback on it may be obtained at
35 https://www.rfc-editor.org/info/rfc8620.
39 Copyright (c) 2019 IETF Trust and the persons identified as the
40 document authors. All rights reserved.
42 This document is subject to BCP 78 and the IETF Trust's Legal
43 Provisions Relating to IETF Documents
44 (https://trustee.ietf.org/license-info) in effect on the date of
45 publication of this document. Please review these documents
46 carefully, as they describe your rights and restrictions with respect
47 to this document. Code Components extracted from this document must
48 include Simplified BSD License text as described in Section 4.e of
49 the Trust Legal Provisions and are provided without warranty as
50 described in the Simplified BSD License.
58Jenkins & Newman Standards Track [Page 1]
60RFC 8620 JMAP July 2019
65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
66 1.1. Notational Conventions . . . . . . . . . . . . . . . . . 4
67 1.2. The Id Data Type . . . . . . . . . . . . . . . . . . . . 6
68 1.3. The Int and UnsignedInt Data Types . . . . . . . . . . . 6
69 1.4. The Date and UTCDate Data Types . . . . . . . . . . . . . 7
70 1.5. JSON as the Data Encoding Format . . . . . . . . . . . . 7
71 1.6. Terminology . . . . . . . . . . . . . . . . . . . . . . . 7
72 1.6.1. User . . . . . . . . . . . . . . . . . . . . . . . . 7
73 1.6.2. Accounts . . . . . . . . . . . . . . . . . . . . . . 7
74 1.6.3. Data Types and Records . . . . . . . . . . . . . . . 8
75 1.7. The JMAP API Model . . . . . . . . . . . . . . . . . . . 8
76 1.8. Vendor-Specific Extensions . . . . . . . . . . . . . . . 9
77 2. The JMAP Session Resource . . . . . . . . . . . . . . . . . . 9
78 2.1. Example . . . . . . . . . . . . . . . . . . . . . . . . . 14
79 2.2. Service Autodiscovery . . . . . . . . . . . . . . . . . . 15
80 3. Structured Data Exchange . . . . . . . . . . . . . . . . . . 16
81 3.1. Making an API Request . . . . . . . . . . . . . . . . . . 16
82 3.2. The Invocation Data Type . . . . . . . . . . . . . . . . 16
83 3.3. The Request Object . . . . . . . . . . . . . . . . . . . 16
84 3.3.1. Example Request . . . . . . . . . . . . . . . . . . . 18
85 3.4. The Response Object . . . . . . . . . . . . . . . . . . . 18
86 3.4.1. Example Response . . . . . . . . . . . . . . . . . . 19
87 3.5. Omitting Arguments . . . . . . . . . . . . . . . . . . . 19
88 3.6. Errors . . . . . . . . . . . . . . . . . . . . . . . . . 19
89 3.6.1. Request-Level Errors . . . . . . . . . . . . . . . . 20
90 3.6.2. Method-Level Errors . . . . . . . . . . . . . . . . . 21
91 3.7. References to Previous Method Results . . . . . . . . . . 22
92 3.8. Localisation of User-Visible Strings . . . . . . . . . . 27
93 3.9. Security . . . . . . . . . . . . . . . . . . . . . . . . 28
94 3.10. Concurrency . . . . . . . . . . . . . . . . . . . . . . . 28
95 4. The Core/echo Method . . . . . . . . . . . . . . . . . . . . 28
96 4.1. Example . . . . . . . . . . . . . . . . . . . . . . . . . 28
97 5. Standard Methods and Naming Convention . . . . . . . . . . . 29
98 5.1. /get . . . . . . . . . . . . . . . . . . . . . . . . . . 29
99 5.2. /changes . . . . . . . . . . . . . . . . . . . . . . . . 30
100 5.3. /set . . . . . . . . . . . . . . . . . . . . . . . . . . 34
101 5.4. /copy . . . . . . . . . . . . . . . . . . . . . . . . . . 40
102 5.5. /query . . . . . . . . . . . . . . . . . . . . . . . . . 42
103 5.6. /queryChanges . . . . . . . . . . . . . . . . . . . . . . 48
104 5.7. Examples . . . . . . . . . . . . . . . . . . . . . . . . 51
105 5.8. Proxy Considerations . . . . . . . . . . . . . . . . . . 58
106 6. Binary Data . . . . . . . . . . . . . . . . . . . . . . . . . 58
107 6.1. Uploading Binary Data . . . . . . . . . . . . . . . . . . 59
108 6.2. Downloading Binary Data . . . . . . . . . . . . . . . . . 60
109 6.3. Blob/copy . . . . . . . . . . . . . . . . . . . . . . . . 61
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116RFC 8620 JMAP July 2019
119 7. Push . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
120 7.1. The StateChange Object . . . . . . . . . . . . . . . . . 63
121 7.1.1. Example . . . . . . . . . . . . . . . . . . . . . . . 64
122 7.2. PushSubscription . . . . . . . . . . . . . . . . . . . . 64
123 7.2.1. PushSubscription/get . . . . . . . . . . . . . . . . 67
124 7.2.2. PushSubscription/set . . . . . . . . . . . . . . . . 68
125 7.2.3. Example . . . . . . . . . . . . . . . . . . . . . . . 69
126 7.3. Event Source . . . . . . . . . . . . . . . . . . . . . . 71
127 8. Security Considerations . . . . . . . . . . . . . . . . . . . 73
128 8.1. Transport Confidentiality . . . . . . . . . . . . . . . . 73
129 8.2. Authentication Scheme . . . . . . . . . . . . . . . . . . 73
130 8.3. Service Autodiscovery . . . . . . . . . . . . . . . . . . 73
131 8.4. JSON Parsing . . . . . . . . . . . . . . . . . . . . . . 74
132 8.5. Denial of Service . . . . . . . . . . . . . . . . . . . . 74
133 8.6. Connection to Unknown Push Server . . . . . . . . . . . . 74
134 8.7. Push Encryption . . . . . . . . . . . . . . . . . . . . . 75
135 8.8. Traffic Analysis . . . . . . . . . . . . . . . . . . . . 76
136 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 76
137 9.1. Assignment of jmap Service Name . . . . . . . . . . . . . 76
138 9.2. Registration of Well-Known URI Suffix for JMAP . . . . . 76
139 9.3. Registration of the jmap URN Sub-namespace . . . . . . . 77
140 9.4. Creation of "JMAP Capabilities" Registry . . . . . . . . 77
141 9.4.1. Preliminary Community Review . . . . . . . . . . . . 77
142 9.4.2. Submit Request to IANA . . . . . . . . . . . . . . . 78
143 9.4.3. Designated Expert Review . . . . . . . . . . . . . . 78
144 9.4.4. Change Procedures . . . . . . . . . . . . . . . . . . 78
145 9.4.5. JMAP Capabilities Registry Template . . . . . . . . . 79
146 9.4.6. Initial Registration for JMAP Core . . . . . . . . . 79
147 9.4.7. Registration for JMAP Error Placeholder in JMAP
148 Capabilities Registry . . . . . . . . . . . . . . . . 80
149 9.5. Creation of "JMAP Error Codes" Registry . . . . . . . . . 80
150 9.5.1. Expert Review . . . . . . . . . . . . . . . . . . . . 80
151 9.5.2. JMAP Error Codes Registry Template . . . . . . . . . 81
152 9.5.3. Initial Contents for the JMAP Error Codes Registry . 81
153 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 86
154 10.1. Normative References . . . . . . . . . . . . . . . . . . 86
155 10.2. Informative References . . . . . . . . . . . . . . . . . 89
156 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 90
170Jenkins & Newman Standards Track [Page 3]
172RFC 8620 JMAP July 2019
177 The JSON Meta Application Protocol (JMAP) is used for synchronising
178 data, such as mail, calendars, or contacts, between a client and a
179 server. It is optimised for mobile and web environments and aims to
180 provide a consistent interface to different data types.
182 This specification is for the generic mechanism of data
183 synchronisation. Further specifications define the data models for
184 different data types that may be synchronised via JMAP.
186 JMAP is designed to make efficient use of limited network resources.
187 Multiple API calls may be batched in a single request to the server,
188 reducing round trips and improving battery life on mobile devices.
189 Push connections remove the need for polling, and an efficient delta
190 update mechanism ensures a minimum amount of data is transferred.
192 JMAP is designed to be horizontally scalable to a very large number
193 of users. This is facilitated by separate endpoints for users after
194 login, the separation of binary and structured data, and a data model
195 for sharing that does not allow data dependencies between accounts.
1971.1. Notational Conventions
199 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
200 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
201 "OPTIONAL" in this document are to be interpreted as described in
202 BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
203 capitals, as shown here.
205 The underlying format used for this specification is JSON.
206 Consequently, the terms "object" and "array" as well as the four
207 primitive types (strings, numbers, booleans, and null) are to be
208 interpreted as described in Section 1 of [RFC8259]. Unless otherwise
209 noted, all the property names and values are case sensitive.
211 Some examples in this document contain "partial" JSON documents used
212 for illustrative purposes. In these examples, three periods "..."
213 are used to indicate a portion of the document that has been removed
216 For compatibility with publishing requirements, line breaks have been
217 inserted inside long JSON strings, with the following continuation
218 lines indented. To form the valid JSON example, any line breaks
219 inside a string must be replaced with a space and any other white
220 space after the line break removed.
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228RFC 8620 JMAP July 2019
231 Unless otherwise specified, examples of API exchanges only show the
232 methodCalls array of the Request object or the methodResponses array
233 of the Response object. For compactness, the rest of the Request/
234 Response object is omitted.
236 Type signatures are given for all JSON values in this document. The
237 following conventions are used:
239 o "*" - The type is undefined (the value could be any type, although
240 permitted values may be constrained by the context of this value).
242 o "String" - The JSON string type.
244 o "Number" - The JSON number type.
246 o "Boolean" - The JSON boolean type.
248 o "A[B]" - A JSON object where the keys are all of type "A", and the
249 values are all of type "B".
251 o "A[]" - An array of values of type "A".
253 o "A|B" - The value is either of type "A" or of type "B".
255 Other types may also be given, with their representation defined
256 elsewhere in this document.
258 Object properties may also have a set of attributes defined along
259 with the type signature. These have the following meanings:
261 o "server-set" -- Only the server can set the value for this
262 property. The client MUST NOT send this property when creating a
263 new object of this type.
265 o "immutable" -- The value MUST NOT change after the object is
268 o "default" -- (This is followed by a JSON value). The value that
269 will be used for this property if it is omitted in an argument or
270 when creating a new object of this type.
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289 All record ids are assigned by the server and are immutable.
291 Where "Id" is given as a data type, it means a "String" of at least 1
292 and a maximum of 255 octets in size, and it MUST only contain
293 characters from the "URL and Filename Safe" base64 alphabet, as
294 defined in Section 5 of [RFC4648], excluding the pad character ("=").
295 This means the allowed characters are the ASCII alphanumeric
296 characters ("A-Za-z0-9"), hyphen ("-"), and underscore ("_").
298 These characters are safe to use in almost any context (e.g.,
299 filesystems, URIs, and IMAP atoms). For maximum safety, servers
300 SHOULD also follow defensive allocation strategies to avoid creating
301 risks where glob completion or data type detection may be present
302 (e.g., on filesystems or in spreadsheets). In particular, it is wise
305 o Ids starting with a dash
307 o Ids starting with digits
309 o Ids that contain only digits
311 o Ids that differ only by ASCII case (for example, A vs. a)
313 o the specific sequence of three characters "NIL" (because this
314 sequence can be confused with the IMAP protocol expression of the
317 A good solution to these issues is to prefix every id with a single
318 alphabetical character.
3201.3. The Int and UnsignedInt Data Types
322 Where "Int" is given as a data type, it means an integer in the range
323 -2^53+1 <= value <= 2^53-1, the safe range for integers stored in a
324 floating-point double, represented as a JSON "Number".
326 Where "UnsignedInt" is given as a data type, it means an "Int" where
327 the value MUST be in the range 0 <= value <= 2^53-1.
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3431.4. The Date and UTCDate Data Types
345 Where "Date" is given as a type, it means a string in "date-time"
346 format [RFC3339]. To ensure a normalised form, the "time-secfrac"
347 MUST always be omitted if zero, and any letters in the string (e.g.,
348 "T" and "Z") MUST be uppercase. For example,
349 "2014-10-30T14:12:00+08:00".
351 Where "UTCDate" is given as a type, it means a "Date" where the
352 "time-offset" component MUST be "Z" (i.e., it must be in UTC time).
353 For example, "2014-10-30T06:12:00Z".
3551.5. JSON as the Data Encoding Format
357 JSON is a text-based data interchange format as specified in
358 [RFC8259]. The Internet JSON (I-JSON) format defined in [RFC7493] is
359 a strict subset of this, adding restrictions to avoid potentially
360 confusing scenarios (for example, it mandates that an object MUST NOT
361 have two members with the same name).
363 All data sent from the client to the server or from the server to the
364 client (except binary file upload/download) MUST be valid I-JSON
365 according to the RFC and is therefore case sensitive and encoded in
372 A user is a person accessing data via JMAP. A user has a set of
373 permissions determining the data that they can see.
377 An account is a collection of data. A single account may contain an
378 arbitrary set of data types, for example, a collection of mail,
379 contacts, and calendars. Most JMAP methods take a mandatory
380 "accountId" argument that specifies on which account the operations
383 An account is not the same as a user, although it is common for a
384 primary account to directly belong to the user. For example, you may
385 have an account that contains data for a group or business, to which
386 multiple users have access.
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399 A single set of credentials may provide access to multiple accounts,
400 for example, if another user is sharing their work calendar with the
401 authenticated user or if there is a group mailbox for a support-desk
404 In the event of a severe internal error, a server may have to
405 reallocate ids or do something else that violates standard JMAP data
406 constraints for an account. In this situation, the data on the
407 server is no longer compatible with cached data the client may have
408 from before. The server MUST treat this as though the account has
409 been deleted and then recreated with a new account id. Clients will
410 then be forced to throw away any data with the old account id and
411 refetch all data from scratch.
4131.6.3. Data Types and Records
415 JMAP provides a uniform interface for creating, retrieving, updating,
416 and deleting various types of objects. A "data type" is a collection
417 of named, typed properties, just like the schema for a database
418 table. Each instance of a data type is called a "record".
420 The id of a record is immutable and assigned by the server. The id
421 MUST be unique among all records of the *same type* within the *same
422 account*. Ids may clash across accounts or for two records of
423 different types within the same account.
4251.7. The JMAP API Model
427 JMAP uses HTTP [RFC7230] to expose API, push, upload, and download
428 resources. All HTTP requests MUST use the "https://" scheme (HTTP
429 over TLS [RFC2818]). All HTTP requests MUST be authenticated.
431 An authenticated client can fetch the user's Session object with
432 details about the data and capabilities the server can provide as
433 shown in Section 2. The client may then exchange data with the
434 server in the following ways:
436 1. The client may make an API request to the server to get or set
437 structured data. This request consists of an ordered series of
438 method calls. These are processed by the server, which then
439 returns an ordered series of responses. This is described in
440 Sections 3, 4, and 5.
442 2. The client may download or upload binary files from/to the
443 server. This is detailed in Section 6.
445 3. The client may connect to a push channel on the server, to be
446 notified when data has changed. This is explained in Section 7.
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4551.8. Vendor-Specific Extensions
457 Individual services will have custom features they wish to expose
458 over JMAP. This may take the form of extra data types and/or methods
459 not in the spec, extra arguments to JMAP methods, or extra properties
460 on existing data types (which may also appear in arguments to methods
461 that take property names).
463 The server can advertise custom extensions it supports by including
464 the identifiers in the capabilities object. Identifiers for vendor
465 extensions MUST be a URL belonging to a domain owned by the vendor,
466 to avoid conflict. The URL SHOULD resolve to documentation for the
467 changes the extension makes.
469 The client MUST opt in to use an extension by passing the appropriate
470 capability identifier in the "using" array of the Request object, as
471 described in Section 3.3. The server MUST only follow the
472 specifications that are opted into and behave as though it does not
473 implement anything else when processing a request. This is to ensure
474 compatibility with clients that don't know about a specific custom
475 extension and for compatibility with future versions of JMAP.
4772. The JMAP Session Resource
479 You need two things to connect to a JMAP server:
481 1. The URL for the JMAP Session resource. This may be requested
482 directly from the user or discovered automatically based on a
483 username domain (see Section 2.2 below).
485 2. Credentials to authenticate with. How to obtain credentials is
486 out of scope for this document.
488 A successful authenticated GET request to the JMAP Session resource
489 MUST return a JSON-encoded *Session* object, giving details about the
490 data and capabilities the server can provide to the client given
491 those credentials. It has the following properties:
493 o capabilities: "String[Object]"
495 An object specifying the capabilities of this server. Each key is
496 a URI for a capability supported by the server. The value for
497 each of these keys is an object with further information about the
498 server's capabilities in relation to that capability.
500 The client MUST ignore any properties it does not understand.
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511 The capabilities object MUST include a property called
512 "urn:ietf:params:jmap:core". The value of this property is an
513 object that MUST contain the following information on server
514 capabilities (suggested minimum values for limits are supplied
515 that allow clients to make efficient use of the network):
517 * maxSizeUpload: "UnsignedInt"
519 The maximum file size, in octets, that the server will accept
520 for a single file upload (for any purpose). Suggested minimum:
523 * maxConcurrentUpload: "UnsignedInt"
525 The maximum number of concurrent requests the server will
526 accept to the upload endpoint. Suggested minimum: 4.
528 * maxSizeRequest: "UnsignedInt"
530 The maximum size, in octets, that the server will accept for a
531 single request to the API endpoint. Suggested minimum:
534 * maxConcurrentRequests: "UnsignedInt"
536 The maximum number of concurrent requests the server will
537 accept to the API endpoint. Suggested minimum: 4.
539 * maxCallsInRequest: "UnsignedInt"
541 The maximum number of method calls the server will accept in a
542 single request to the API endpoint. Suggested minimum: 16.
544 * maxObjectsInGet: "UnsignedInt"
546 The maximum number of objects that the client may request in a
547 single /get type method call. Suggested minimum: 500.
549 * maxObjectsInSet: "UnsignedInt"
551 The maximum number of objects the client may send to create,
552 update, or destroy in a single /set type method call. This is
553 the combined total, e.g., if the maximum is 10, you could not
554 create 7 objects and destroy 6, as this would be 13 actions,
555 which exceeds the limit. Suggested minimum: 500.
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567 * collationAlgorithms: "String[]"
569 A list of identifiers for algorithms registered in the
570 collation registry, as defined in [RFC4790], that the server
571 supports for sorting when querying records.
573 Specifications for future capabilities will define their own
574 properties on the capabilities object.
576 Servers MAY advertise vendor-specific JMAP extensions, as
577 described in Section 1.8. To avoid conflict, an identifier for a
578 vendor-specific extension MUST be a URL with a domain owned by the
579 vendor. Clients MUST opt in to any capability it wishes to use
582 o accounts: "Id[Account]"
584 A map of an account id to an Account object for each account (see
585 Section 1.6.2) the user has access to. An *Account* object has
586 the following properties:
590 A user-friendly string to show when presenting content from
591 this account, e.g., the email address representing the owner of
594 * isPersonal: "Boolean"
596 This is true if the account belongs to the authenticated user
597 rather than a group account or a personal account of another
598 user that has been shared with them.
600 * isReadOnly: "Boolean"
602 This is true if the entire account is read-only.
604 * accountCapabilities: "String[Object]"
606 The set of capability URIs for the methods supported in this
607 account. Each key is a URI for a capability that has methods
608 you can use with this account. The value for each of these
609 keys is an object with further information about the account's
610 permissions and restrictions with respect to this capability,
611 as defined in the capability's specification.
613 The client MUST ignore any properties it does not understand.
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623 The server advertises the full list of capabilities it supports
624 in the capabilities object, as defined above. If the
625 capability defines new methods, the server MUST include it in
626 the accountCapabilities object if the user may use those
627 methods with this account. It MUST NOT include it in the
628 accountCapabilities object if the user cannot use those methods
631 For example, you may have access to your own account with mail,
632 calendars, and contacts data and also a shared account that
633 only has contacts data (a business address book, for example).
634 In this case, the accountCapabilities property on the first
635 account would include something like
636 "urn:ietf:params:jmap:mail", "urn:ietf:params:jmap:calendars",
637 and "urn:ietf:params:jmap:contacts", while the second account
638 would just have the last of these.
640 Attempts to use the methods defined in a capability with one of
641 the accounts that does not support that capability are rejected
642 with an "accountNotSupportedByMethod" error (see "Method-Level
643 Errors", Section 3.6.2).
645 o primaryAccounts: "String[Id]"
647 A map of capability URIs (as found in accountCapabilities) to the
648 account id that is considered to be the user's main or default
649 account for data pertaining to that capability. If no account
650 being returned belongs to the user, or in any other way there is
651 no appropriate way to determine a default account, there MAY be no
652 entry for a particular URI, even though that capability is
653 supported by the server (and in the capabilities object).
654 "urn:ietf:params:jmap:core" SHOULD NOT be present.
658 The username associated with the given credentials, or the empty
663 The URL to use for JMAP API requests.
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679 o downloadUrl: "String"
681 The URL endpoint to use when downloading files, in URI Template
682 (level 1) format [RFC6570]. The URL MUST contain variables called
683 "accountId", "blobId", "type", and "name". The use of these
684 variables is described in Section 6.2. Due to potential encoding
685 issues with slashes in content types, it is RECOMMENDED to put the
686 "type" variable in the query section of the URL.
688 o uploadUrl: "String"
690 The URL endpoint to use when uploading files, in URI Template
691 (level 1) format [RFC6570]. The URL MUST contain a variable
692 called "accountId". The use of this variable is described in
695 o eventSourceUrl: "String"
697 The URL to connect to for push events, as described in
698 Section 7.3, in URI Template (level 1) format [RFC6570]. The URL
699 MUST contain variables called "types", "closeafter", and "ping".
700 The use of these variables is described in Section 7.3.
704 A (preferably short) string representing the state of this object
705 on the server. If the value of any other property on the Session
706 object changes, this string will change. The current value is
707 also returned on the API Response object (see Section 3.4),
708 allowing clients to quickly determine if the session information
709 has changed (e.g., an account has been added or removed), so they
710 need to refetch the object.
712 To ensure future compatibility, other properties MAY be included on
713 the Session object. Clients MUST ignore any properties they are not
716 Implementors must take care to avoid inappropriate caching of the
717 Session object at the HTTP layer. Since the client should only
718 refetch when it detects there is a change (via the sessionState
719 property of an API response), it is RECOMMENDED to disable HTTP
720 caching altogether, for example, by setting "Cache-Control: no-cache,
721 no-store, must-revalidate" on the response.
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737 In the following example Session object, the user has access to their
738 own mail and contacts via JMAP, as well as read-only access to shared
739 mail from another user. The server is advertising a custom
740 "https://example.com/apis/foobar" capability.
744 "urn:ietf:params:jmap:core": {
745 "maxSizeUpload": 50000000,
746 "maxConcurrentUpload": 8,
747 "maxSizeRequest": 10000000,
748 "maxConcurrentRequest": 8,
749 "maxCallsInRequest": 32,
750 "maxObjectsInGet": 256,
751 "maxObjectsInSet": 128,
752 "collationAlgorithms": [
758 "urn:ietf:params:jmap:mail": {}
759 "urn:ietf:params:jmap:contacts": {},
760 "https://example.com/apis/foobar": {
761 "maxFoosFinangled": 42
766 "name": "john@example.com",
769 "accountCapabilities": {
770 "urn:ietf:params:jmap:mail": {
771 "maxMailboxesPerEmail": null,
772 "maxMailboxDepth": 10,
775 "urn:ietf:params:jmap:contacts": {
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788RFC 8620 JMAP July 2019
792 "name": "jane@example.com",
795 "accountCapabilities": {
796 "urn:ietf:params:jmap:mail": {
797 "maxMailboxesPerEmail": 1,
798 "maxMailboxDepth": 10,
805 "urn:ietf:params:jmap:mail": "A13824",
806 "urn:ietf:params:jmap:contacts": "A13824"
808 "username": "john@example.com",
809 "apiUrl": "https://jmap.example.com/api/",
810 "downloadUrl": "https://jmap.example.com
811 /download/{accountId}/{blobId}/{name}?accept={type}",
812 "uploadUrl": "https://jmap.example.com/upload/{accountId}/",
813 "eventSourceUrl": "https://jmap.example.com
814 /eventsource/?types={types}&closeafter={closeafter}&ping={ping}",
815 "state": "75128aab4b1b"
8182.2. Service Autodiscovery
820 There are two standardised autodiscovery methods in use for Internet
823 o DNS SRV (see [RFC2782], [RFC6186], and [RFC6764])
825 o .well-known/servicename (see [RFC8615])
827 A JMAP-supporting host for the domain "example.com" SHOULD publish a
828 SRV record "_jmap._tcp.example.com" that gives a hostname and port
829 (usually port "443"). The JMAP Session resource is then
830 "https://${hostname}[:${port}]/.well-known/jmap" (following any
833 If the client has a username in the form of an email address, it MAY
834 use the domain portion of this to attempt autodiscovery of the JMAP
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8473. Structured Data Exchange
849 The client may make an API request to the server to get or set
850 structured data. This request consists of an ordered series of
851 method calls. These are processed by the server, which then returns
852 an ordered series of responses.
8543.1. Making an API Request
856 To make an API request, the client makes an authenticated POST
857 request to the API resource, which is defined by the "apiUrl"
858 property in the Session object (see Section 2).
860 The request MUST be of type "application/json" and consist of a
861 single JSON-encoded "Request" object, as defined in Section 3.3. If
862 successful, the response MUST also be of type "application/json" and
863 consist of a single "Response" object, as defined in Section 3.4.
8653.2. The Invocation Data Type
867 Method calls and responses are represented by the *Invocation* data
868 type. This is a tuple, represented as a JSON array containing three
871 1. A "String" *name* of the method to call or of the response.
873 2. A "String[*]" object containing named *arguments* for that method
876 3. A "String" *method call id*: an arbitrary string from the client
877 to be echoed back with the responses emitted by that method call
878 (a method may return 1 or more responses, as it may make implicit
879 calls to other methods; all responses initiated by this method
880 call get the same method call id in the response).
8823.3. The Request Object
884 A *Request* object has the following properties:
888 The set of capabilities the client wishes to use. The client MAY
889 include capability identifiers even if the method calls it makes
890 do not utilise those capabilities. The server advertises the set
891 of specifications it supports in the Session object (see
892 Section 2), as keys on the "capabilities" property.
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903 o methodCalls: "Invocation[]"
905 An array of method calls to process on the server. The method
906 calls MUST be processed sequentially, in order.
908 o createdIds: "Id[Id]" (optional)
910 A map of a (client-specified) creation id to the id the server
911 assigned when a record was successfully created.
913 As described later in this specification, some records may have a
914 property that contains the id of another record. To allow more
915 efficient network usage, you can set this property to reference a
916 record created earlier in the same API request. Since the real id
917 is unknown when the request is created, the client can instead
918 specify the creation id it assigned, prefixed with a "#" (see
919 Section 5.3 for more details).
921 As the server processes API requests, any time it successfully
922 creates a new record, it adds the creation id to this map (see the
923 "create" argument to /set in Section 5.3), with the server-
924 assigned real id as the value. If it comes across a reference to
925 a creation id in a create/update, it looks it up in the map and
926 replaces the reference with the real id, if found.
928 The client can pass an initial value for this map as the
929 "createdIds" property of the Request object. This may be an empty
930 object. If given in the request, the response will also include a
931 createdIds property. This allows proxy servers to easily split a
932 JMAP request into multiple JMAP requests to send to different
933 servers. For example, it could send the first two method calls to
934 server A, then the third to server B, before sending the fourth to
935 server A again. By passing the createdIds of the previous
936 response to the next request, it can ensure all of these still
937 resolve. See Section 5.8 for further discussion of proxy
940 Future specifications MAY add further properties to the Request
941 object to extend the semantics. To ensure forwards compatibility, a
942 server MUST ignore any other properties it does not understand on the
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9593.3.1. Example Request
962 "using": [ "urn:ietf:params:jmap:core", "urn:ietf:params:jmap:mail" ],
971 [ "method3", {}, "c3" ]
9753.4. The Response Object
977 A *Response* object has the following properties:
979 o methodResponses: "Invocation[]"
981 An array of responses, in the same format as the "methodCalls" on
982 the Request object. The output of the methods MUST be added to
983 the "methodResponses" array in the same order that the methods are
986 o createdIds: "Id[Id]" (optional; only returned if given in the
989 A map of a (client-specified) creation id to the id the server
990 assigned when a record was successfully created. This MUST
991 include all creation ids passed in the original createdIds
992 parameter of the Request object, as well as any additional ones
993 added for newly created records.
995 o sessionState: "String"
997 The current value of the "state" string on the Session object, as
998 described in Section 2. Clients may use this to detect if this
999 object has changed and needs to be refetched.
1001 Unless otherwise specified, if the method call completed
1002 successfully, its response name is the same as the method name in the
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10153.4.1. Example Response
1018 "methodResponses": [
1026 [ "anotherResponseFromMethod2", {
1028 "yetmoredata": "Hello"
1031 "type":"unknownMethod"
1034 "sessionState": "75128aab4b1b"
10373.5. Omitting Arguments
1039 An argument to a method may be specified to have a default value. If
1040 omitted by the client, the server MUST treat the method call the same
1041 as if the default value had been specified. Similarly, the server
1042 MAY omit any argument in a response that has the default value.
1044 Unless otherwise specified in a method description, null is the
1045 default value for any argument in a request or response where this is
1046 allowed by the type signature. Other arguments may only be omitted
1047 if an explicit default value is defined in the method description.
1051 There are three different levels of granularity at which an error may
1052 be returned in JMAP.
1054 When an API request is made, the request as a whole may be rejected
1055 due to rate limiting, malformed JSON, request for an unknown
1056 capability, etc. In this case, the entire request is rejected with
1057 an appropriate HTTP error response code and an additional JSON body
1058 with more detail for the client.
1060 Provided the request itself is syntactically valid (the JSON is valid
1061 and when decoded, it matches the type signature of a Request object),
1062 the methods within it are executed sequentially by the server. Each
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1071 method may individually fail, for example, if invalid arguments are
1072 given or an unknown method name is called.
1074 Finally, methods that make changes to the server state often act upon
1075 a number of different records within a single call. Each record
1076 change may be separately rejected with a SetError, as described in
10793.6.1. Request-Level Errors
1081 When an HTTP error response is returned to the client, the server
1082 SHOULD return a JSON "problem details" object as the response body,
1085 The following problem types are defined:
1087 o "urn:ietf:params:jmap:error:unknownCapability"
1088 The client included a capability in the "using" property of the
1089 request that the server does not support.
1091 o "urn:ietf:params:jmap:error:notJSON"
1092 The content type of the request was not "application/json" or the
1093 request did not parse as I-JSON.
1095 o "urn:ietf:params:jmap:error:notRequest"
1096 The request parsed as JSON but did not match the type signature of
1099 o "urn:ietf:params:jmap:error:limit"
1100 The request was not processed as it would have exceeded one of the
1101 request limits defined on the capability object, such as
1102 maxSizeRequest, maxCallsInRequest, or maxConcurrentRequests. A
1103 "limit" property MUST also be present on the "problem details"
1104 object, containing the name of the limit being applied.
1109 "type": "urn:ietf:params:jmap:error:unknownCapability",
1111 "detail": "The Request object used capability
1112 'https://example.com/apis/foobar', which is not supported
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1124RFC 8620 JMAP July 2019
1130 "type": "urn:ietf:params:jmap:error:limit",
1131 "limit": "maxSizeRequest",
1133 "detail": "The request is larger than the server is willing to
11373.6.2. Method-Level Errors
1139 If a method encounters an error, the appropriate "error" response
1140 MUST be inserted at the current point in the "methodResponses" array
1141 and, unless otherwise specified, further processing MUST NOT happen
1142 within that method call.
1144 Any further method calls in the request MUST then be processed as
1145 normal. Errors at the method level MUST NOT generate an HTTP-level
1148 An "error" response looks like this:
1151 "type": "unknownMethod"
1154 The response name is "error", and it MUST have a type property.
1155 Other properties may be present with further information; these are
1156 detailed in the error type descriptions where appropriate.
1158 With the exception of when the "serverPartialFail" error is returned,
1159 the externally visible state of the server MUST NOT have changed if
1160 an error is returned at the method level.
1162 The following error types are defined, which may be returned for any
1163 method call where appropriate:
1165 "serverUnavailable": Some internal server resource was temporarily
1166 unavailable. Attempting the same operation later (perhaps after a
1167 backoff with a random factor) may succeed.
1169 "serverFail": An unexpected or unknown error occurred during the
1170 processing of the call. A "description" property should provide more
1171 details about the error. The method call made no changes to the
1172 server's state. Attempting the same operation again is expected to
1173 fail again. Contacting the service administrator is likely necessary
1174 to resolve this problem if it is persistent.
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1183 "serverPartialFail": Some, but not all, expected changes described by
1184 the method occurred. The client MUST resynchronise impacted data to
1185 determine server state. Use of this error is strongly discouraged.
1187 "unknownMethod": The server does not recognise this method name.
1189 "invalidArguments": One of the arguments is of the wrong type or is
1190 otherwise invalid, or a required argument is missing. A
1191 "description" property MAY be present to help debug with an
1192 explanation of what the problem was. This is a non-localised string,
1193 and it is not intended to be shown directly to end users.
1195 "invalidResultReference": The method used a result reference for one
1196 of its arguments (see Section 3.7), but this failed to resolve.
1198 "forbidden": The method and arguments are valid, but executing the
1199 method would violate an Access Control List (ACL) or other
1202 "accountNotFound": The accountId does not correspond to a valid
1205 "accountNotSupportedByMethod": The accountId given corresponds to a
1206 valid account, but the account does not support this method or data
1209 "accountReadOnly": This method modifies state, but the account is
1210 read-only (as returned on the corresponding Account object in the
1211 JMAP Session resource).
1213 Further possible errors for a particular method are specified in the
1214 method descriptions.
1216 Further general errors MAY be defined in future RFCs. Should a
1217 client receive an error type it does not understand, it MUST treat it
1218 the same as the "serverFail" type.
12203.7. References to Previous Method Results
1222 To allow clients to make more efficient use of the network and avoid
1223 round trips, an argument to one method can be taken from the result
1224 of a previous method call in the same request.
1226 To do this, the client prefixes the argument name with "#" (an
1227 octothorpe). The value is a ResultReference object as described
1228 below. When processing a method call, the server MUST first check
1229 the arguments object for any names beginning with "#". If found, the
1230 result reference should be resolved and the value used as the "real"
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1239 argument. The method is then processed as normal. If any result
1240 reference fails to resolve, the whole method MUST be rejected with an
1241 "invalidResultReference" error. If an arguments object contains the
1242 same argument name in normal and referenced form (e.g., "foo" and
1243 "#foo"), the method MUST return an "invalidArguments" error.
1245 A *ResultReference* object has the following properties:
1247 o resultOf: "String"
1249 The method call id (see Section 3.2) of a previous method call in
1250 the current request.
1254 The required name of a response to that method call.
1258 A pointer into the arguments of the response selected via the name
1259 and resultOf properties. This is a JSON Pointer [RFC6901], except
1260 it also allows the use of "*" to map through an array (see the
1265 1. Find the first response with a method call id identical to the
1266 "resultOf" property of the ResultReference in the
1267 "methodResponses" array from previously processed method calls in
1268 the same request. If none, evaluation fails.
1270 2. If the response name is not identical to the "name" property of
1271 the ResultReference, evaluation fails.
1273 3. Apply the "path" to the arguments object of the response (the
1274 second item in the response array) following the JSON Pointer
1275 algorithm [RFC6901], except with the following addition in
1276 "Evaluation" (see Section 4):
1278 If the currently referenced value is a JSON array, the reference
1279 token may be exactly the single character "*", making the new
1280 referenced value the result of applying the rest of the JSON
1281 Pointer tokens to every item in the array and returning the
1282 results in the same order in a new array. If the result of
1283 applying the rest of the pointer tokens to each item was itself
1284 an array, the contents of this array are added to the output
1285 rather than the array itself (i.e., the result is flattened from
1286 an array of arrays to a single array). If the result of applying
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1295 the rest of the pointer tokens to a value was itself an array,
1296 its items should be included individually in the output rather
1297 than including the array itself (i.e., the result is flattened
1298 from an array of arrays to a single array).
1300 As a simple example, suppose we have the following API request
1305 "sinceState": "abcdef"
1311 "name": "Foo/changes",
1316 After executing the first method call, the "methodResponses" array
1321 "oldState": "abcdef",
1322 "newState": "123456",
1323 "hasMoreChanges": false,
1324 "created": [ "f1", "f4" ],
1329 To execute the "Foo/get" call, we look through the arguments and find
1330 there is one with a "#" prefix. To resolve this, we apply the
1333 1. Find the first response with method call id "t0". The "Foo/
1334 changes" response fulfils this criterion.
1336 2. Check that the response name is the same as in the result
1337 reference. It is, so this is fine.
1339 3. Apply the "path" as a JSON Pointer to the arguments object. This
1340 simply selects the "created" property, so the result of
1341 evaluating is: [ "f1", "f4" ].
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1348RFC 8620 JMAP July 2019
1351 The JMAP server now continues to process the "Foo/get" call as though
1356 "ids": [ "f1", "f4" ]
1359 Now, a more complicated example using the JMAP Mail data model: fetch
1360 the "from"/"date"/"subject" for every Email in the first 10 Threads
1361 in the inbox (sorted newest first):
1365 "filter": { "inMailbox": "id_of_inbox" },
1366 "sort": [{ "property": "receivedAt", "isAscending": false }],
1367 "collapseThreads": true,
1370 "calculateTotal": true
1376 "name": "Email/query",
1379 "properties": [ "threadId" ]
1385 "name": "Email/get",
1386 "path": "/list/*/threadId"
1393 "name": "Thread/get",
1394 "path": "/list/*/emailIds"
1396 "properties": [ "from", "receivedAt", "subject" ]
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1404RFC 8620 JMAP July 2019
1407 After executing the first 3 method calls, the "methodResponses" array
1412 "queryState": "abcdefg",
1413 "canCalculateChanges": true,
1416 "ids": [ "msg1023", "msg223", "msg110", "msg93", "msg91",
1417 "msg38", "msg36", "msg33", "msg11", "msg1" ]
1424 "threadId": "trd194"
1427 "threadId": "trd114"
1438 "emailIds": [ "msg1020", "msg1021", "msg1023" ]
1441 "emailIds": [ "msg201", "msg223" ]
1448 To execute the final "Email/get" call, we look through the arguments
1449 and find there is one with a "#" prefix. To resolve this, we apply
1452 1. Find the first response with method call id "t2". The "Thread/
1453 get" response fulfils this criterion.
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1460RFC 8620 JMAP July 2019
1463 2. "Thread/get" is the name specified in the result reference, so
1466 3. Apply the "path" as a JSON Pointer to the arguments object.
1469 1. "list": get the array of thread objects
1471 2. "*": for each of the items in the array:
1473 a. "emailIds": get the array of Email ids
1475 b. Concatenate these into a single array of all the ids in
1478 The JMAP server now continues to process the "Email/get" call as
1479 though the arguments were:
1483 "ids": [ "msg1020", "msg1021", "msg1023", "msg201", "msg223", ... ],
1484 "properties": [ "from", "receivedAt", "subject" ]
1487 The ResultReference performs a similar role to that of the creation
1488 id, in that it allows a chained method call to refer to information
1489 not available when the request is generated. However, they are
1490 different things and not interchangeable; the only commonality is the
1491 octothorpe used to indicate them.
14933.8. Localisation of User-Visible Strings
1495 If returning a custom string to be displayed to the user, for
1496 example, an error message, the server SHOULD use information from the
1497 Accept-Language header of the request (as defined in Section 5.3.5 of
1498 [RFC7231]) to choose the best available localisation. The Content-
1499 Language header of the response (see Section 3.1.3.2 of [RFC7231])
1500 SHOULD indicate the language being used for user-visible strings.
1502 For example, suppose a request was made with the following header:
1504 Accept-Language: fr-CH, fr;q=0.9, de;q=0.8, en;q=0.7, *;q=0.5
1506 and a method generated an error to display to the user. The server
1507 has translations of the error message in English and German. Looking
1508 at the Accept-Language header, the user's preferred language is
1509 French. Since we don't have a translation for this, we look at the
1514Jenkins & Newman Standards Track [Page 27]
1516RFC 8620 JMAP July 2019
1519 next most preferred, which is German. We have a German translation,
1520 so the server returns this and indicates the language chosen in a
1521 Content-Language header like so:
1523 Content-Language: de
1527 As always, the server must be strict about data received from the
1528 client. Arguments need to be checked for validity; a malicious user
1529 could attempt to find an exploit through the API. In case of invalid
1530 arguments (unknown/insufficient/wrong type for data, etc.), the
1531 method MUST return an "invalidArguments" error and terminate.
1535 Method calls within a single request MUST be executed in order.
1536 However, method calls from different concurrent API requests may be
1537 interleaved. This means that the data on the server may change
1538 between two method calls within a single API request.
15404. The Core/echo Method
1542 The "Core/echo" method returns exactly the same arguments as it is
1543 given. It is useful for testing if you have a valid authenticated
1544 connection to a JMAP API endpoint.
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15755. Standard Methods and Naming Convention
1577 JMAP provides a uniform interface for creating, retrieving, updating,
1578 and deleting objects of a particular type. For a "Foo" data type,
1579 records of that type would be fetched via a "Foo/get" call and
1580 modified via a "Foo/set" call. Delta updates may be fetched via a
1581 "Foo/changes" call. These methods all follow a standard format as
1584 Some types may not have all these methods. Specifications defining
1585 types MUST specify which methods are available for the type.
1589 Objects of type Foo are fetched via a call to "Foo/get".
1591 It takes the following arguments:
1595 The id of the account to use.
1599 The ids of the Foo objects to return. If null, then *all* records
1600 of the data type are returned, if this is supported for that data
1601 type and the number of records does not exceed the
1602 "maxObjectsInGet" limit.
1604 o properties: "String[]|null"
1606 If supplied, only the properties listed in the array are returned
1607 for each Foo object. If null, all properties of the object are
1608 returned. The id property of the object is *always* returned,
1609 even if not explicitly requested. If an invalid property is
1610 requested, the call MUST be rejected with an "invalidArguments"
1613 The response has the following arguments:
1617 The id of the account used for the call.
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1633 A (preferably short) string representing the state on the server
1634 for *all* the data of this type in the account (not just the
1635 objects returned in this call). If the data changes, this string
1636 MUST change. If the Foo data is unchanged, servers SHOULD return
1637 the same state string on subsequent requests for this data type.
1638 When a client receives a response with a different state string to
1639 a previous call, it MUST either throw away all currently cached
1640 objects for the type or call "Foo/changes" to get the exact
1645 An array of the Foo objects requested. This is the *empty array*
1646 if no objects were found or if the "ids" argument passed in was
1647 also an empty array. The results MAY be in a different order to
1648 the "ids" in the request arguments. If an identical id is
1649 included more than once in the request, the server MUST only
1650 include it once in either the "list" or the "notFound" argument of
1655 This array contains the ids passed to the method for records that
1656 do not exist. The array is empty if all requested ids were found
1657 or if the "ids" argument passed in was either null or an empty
1660 The following additional error may be returned instead of the "Foo/
1663 "requestTooLarge": The number of ids requested by the client exceeds
1664 the maximum number the server is willing to process in a single
1669 When the state of the set of Foo records in an account changes on the
1670 server (whether due to creation, updates, or deletion), the "state"
1671 property of the "Foo/get" response will change. The "Foo/changes"
1672 method allows a client to efficiently update the state of its Foo
1673 cache to match the new state on the server. It takes the following
1678 The id of the account to use.
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1684RFC 8620 JMAP July 2019
1687 o sinceState: "String"
1689 The current state of the client. This is the string that was
1690 returned as the "state" argument in the "Foo/get" response. The
1691 server will return the changes that have occurred since this
1694 o maxChanges: "UnsignedInt|null"
1696 The maximum number of ids to return in the response. The server
1697 MAY choose to return fewer than this value but MUST NOT return
1698 more. If not given by the client, the server may choose how many
1699 to return. If supplied by the client, the value MUST be a
1700 positive integer greater than 0. If a value outside of this range
1701 is given, the server MUST reject the call with an
1702 "invalidArguments" error.
1704 The response has the following arguments:
1708 The id of the account used for the call.
1710 o oldState: "String"
1712 This is the "sinceState" argument echoed back; it's the state from
1713 which the server is returning changes.
1715 o newState: "String"
1717 This is the state the client will be in after applying the set of
1718 changes to the old state.
1720 o hasMoreChanges: "Boolean"
1722 If true, the client may call "Foo/changes" again with the
1723 "newState" returned to get further updates. If false, "newState"
1724 is the current server state.
1728 An array of ids for records that have been created since the old
1733 An array of ids for records that have been updated since the old
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1745 An array of ids for records that have been destroyed since the old
1748 If a record has been created AND updated since the old state, the
1749 server SHOULD just return the id in the "created" list but MAY return
1750 it in the "updated" list as well.
1752 If a record has been updated AND destroyed since the old state, the
1753 server SHOULD just return the id in the "destroyed" list but MAY
1754 return it in the "updated" list as well.
1756 If a record has been created AND destroyed since the old state, the
1757 server SHOULD remove the id from the response entirely. However, it
1758 MAY include it in just the "destroyed" list or in both the
1759 "destroyed" and "created" lists.
1761 If a "maxChanges" is supplied, or set automatically by the server,
1762 the server MUST ensure the number of ids returned across "created",
1763 "updated", and "destroyed" does not exceed this limit. If there are
1764 more changes than this between the client's state and the current
1765 server state, the server SHOULD generate an update to take the client
1766 to an intermediate state, from which the client can continue to call
1767 "Foo/changes" until it is fully up to date. If it is unable to
1768 calculate an intermediate state, it MUST return a
1769 "cannotCalculateChanges" error response instead.
1771 When generating intermediate states, the server may choose how to
1772 divide up the changes. For many types, it will provide a better user
1773 experience to return the more recent changes first, as this is more
1774 likely to be what the user is most interested in. The client can
1775 then continue to page in the older changes while the user is viewing
1776 the newer data. For example, suppose a server went through the
1779 A -> B -> C -> D -> E
1781 And a client asks for changes from state "B". The server might first
1782 get the ids of records created, updated, or destroyed between states
1783 D and E, returning them with:
1786 hasMoreChanges: true
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1796RFC 8620 JMAP July 2019
1799 The client will then ask for the change from state "B-D-E", and the
1800 server can return the changes between states C and D, returning:
1803 hasMoreChanges: true
1805 Finally, the client will request the changes from "B-C-E", and the
1806 server can return the changes between states B and C, returning:
1809 hasMoreChanges: false
1811 Should the state on the server be modified in the middle of all this
1812 (to "F"), the server still does the same, but now when the update to
1813 state "E" is returned, it would indicate that it still has more
1814 changes for the client to fetch.
1816 Where multiple changes to a record are split across different
1817 intermediate states, the server MUST NOT return a record as created
1818 after a response that deems it as updated or destroyed, and it MUST
1819 NOT return a record as destroyed before a response that deems it as
1820 created or updated. The server may have to coalesce multiple changes
1821 to a record to satisfy this requirement.
1823 The following additional errors may be returned instead of the "Foo/
1826 "cannotCalculateChanges": The server cannot calculate the changes
1827 from the state string given by the client. Usually, this is due to
1828 the client's state being too old or the server being unable to
1829 produce an update to an intermediate state when there are too many
1830 updates. The client MUST invalidate its Foo cache.
1832 Maintaining state to allow calculation of "Foo/changes" can be
1833 expensive for the server, but always returning
1834 "cannotCalculateChanges" severely increases network traffic and
1835 resource usage for the client. To allow efficient sync, servers
1836 SHOULD be able to calculate changes from any state string that was
1837 given to a client within the last 30 days (but of course may support
1838 calculating updates from states older than this).
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1852RFC 8620 JMAP July 2019
1857 Modifying the state of Foo objects on the server is done via the
1858 "Foo/set" method. This encompasses creating, updating, and
1859 destroying Foo records. This allows the server to sort out ordering
1860 and dependencies that may exist if doing multiple operations at once
1861 (for example, to ensure there is always a minimum number of a certain
1864 The "Foo/set" method takes the following arguments:
1868 The id of the account to use.
1870 o ifInState: "String|null"
1872 This is a state string as returned by the "Foo/get" method
1873 (representing the state of all objects of this type in the
1874 account). If supplied, the string must match the current state;
1875 otherwise, the method will be aborted and a "stateMismatch" error
1876 returned. If null, any changes will be applied to the current
1879 o create: "Id[Foo]|null"
1881 A map of a *creation id* (a temporary id set by the client) to Foo
1882 objects, or null if no objects are to be created.
1884 The Foo object type definition may define default values for
1885 properties. Any such property may be omitted by the client.
1887 The client MUST omit any properties that may only be set by the
1888 server (for example, the "id" property on most object types).
1890 o update: "Id[PatchObject]|null"
1892 A map of an id to a Patch object to apply to the current Foo
1893 object with that id, or null if no objects are to be updated.
1895 A *PatchObject* is of type "String[*]" and represents an unordered
1896 set of patches. The keys are a path in JSON Pointer format
1897 [RFC6901], with an implicit leading "/" (i.e., prefix each key
1898 with "/" before applying the JSON Pointer evaluation algorithm).
1900 All paths MUST also conform to the following restrictions; if
1901 there is any violation, the update MUST be rejected with an
1902 "invalidPatch" error:
1906Jenkins & Newman Standards Track [Page 34]
1908RFC 8620 JMAP July 2019
1911 * The pointer MUST NOT reference inside an array (i.e., you MUST
1912 NOT insert/delete from an array; the array MUST be replaced in
1913 its entirety instead).
1915 * All parts prior to the last (i.e., the value after the final
1916 slash) MUST already exist on the object being patched.
1918 * There MUST NOT be two patches in the PatchObject where the
1919 pointer of one is the prefix of the pointer of the other, e.g.,
1920 "alerts/1/offset" and "alerts".
1922 The value associated with each pointer determines how to apply
1925 * If null, set to the default value if specified for this
1926 property; otherwise, remove the property from the patched
1927 object. If the key is not present in the parent, this a no-op.
1929 * Anything else: The value to set for this property (this may be
1930 a replacement or addition to the object being patched).
1932 Any server-set properties MAY be included in the patch if their
1933 value is identical to the current server value (before applying
1934 the patches to the object). Otherwise, the update MUST be
1935 rejected with an "invalidProperties" SetError.
1937 This patch definition is designed such that an entire Foo object
1938 is also a valid PatchObject. The client may choose to optimise
1939 network usage by just sending the diff or may send the whole
1940 object; the server processes it the same either way.
1942 o destroy: "Id[]|null"
1944 A list of ids for Foo objects to permanently delete, or null if no
1945 objects are to be destroyed.
1947 Each creation, modification, or destruction of an object is
1948 considered an atomic unit. It is permissible for the server to
1949 commit changes to some objects but not others; however, it MUST NOT
1950 only commit part of an update to a single record (e.g., update a
1951 "name" property but not a "count" property, if both are supplied in
1954 The final state MUST be valid after the "Foo/set" is finished;
1955 however, the server may have to transition through invalid
1956 intermediate states (not exposed to the client) while processing the
1957 individual create/update/destroy requests. For example, suppose
1958 there is a "name" property that must be unique. A single method call
1962Jenkins & Newman Standards Track [Page 35]
1964RFC 8620 JMAP July 2019
1967 could rename an object A => B and simultaneously rename another
1968 object B => A. If the final state is valid, this is allowed.
1969 Otherwise, each creation, modification, or destruction of an object
1970 should be processed sequentially and accepted/rejected based on the
1971 current server state.
1973 If a create, update, or destroy is rejected, the appropriate error
1974 MUST be added to the notCreated/notUpdated/notDestroyed property of
1975 the response, and the server MUST continue to the next create/update/
1976 destroy. It does not terminate the method.
1978 If an id given cannot be found, the update or destroy MUST be
1979 rejected with a "notFound" set error.
1981 The server MAY skip an update (rejecting it with a "willDestroy"
1982 SetError) if that object is destroyed in the same /set request.
1984 Some records may hold references to other records (foreign keys).
1985 That reference may be set (via create or update) in the same request
1986 as the referenced record is created. To do this, the client refers
1987 to the new record using its creation id prefixed with a "#". The
1988 order of the method calls in the request by the client MUST be such
1989 that the record being referenced is created in the same or an earlier
1990 call. Thus, the server never has to look ahead. Instead, while
1991 processing a request, the server MUST keep a simple map for the
1992 duration of the request of creation id to record id for each newly
1993 created record, so it can substitute in the correct value if
1994 necessary in later method calls. In the case of records with
1995 references to the same type, the server MUST order the creates and
1996 updates within a single method call so that creates happen before
1997 their creation ids are referenced by another create/update/destroy in
2000 Creation ids are not scoped by type but are a single map for all
2001 types. A client SHOULD NOT reuse a creation id anywhere in the same
2002 API request. If a creation id is reused, the server MUST map the
2003 creation id to the most recently created item with that id. To allow
2004 easy proxying of API requests, an initial set of creation id to real
2005 id values may be passed with a request (see "The Request Object",
2006 Section 3.3) and the final state of the map passed out with the
2007 response (see "The Response Object", Section 3.4).
2009 The response has the following arguments:
2013 The id of the account used for the call.
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2023 o oldState: "String|null"
2025 The state string that would have been returned by "Foo/get" before
2026 making the requested changes, or null if the server doesn't know
2027 what the previous state string was.
2029 o newState: "String"
2031 The state string that will now be returned by "Foo/get".
2033 o created: "Id[Foo]|null"
2035 A map of the creation id to an object containing any properties of
2036 the created Foo object that were not sent by the client. This
2037 includes all server-set properties (such as the "id" in most
2038 object types) and any properties that were omitted by the client
2039 and thus set to a default by the server.
2041 This argument is null if no Foo objects were successfully created.
2043 o updated: "Id[Foo|null]|null"
2045 The keys in this map are the ids of all Foos that were
2046 successfully updated.
2048 The value for each id is a Foo object containing any property that
2049 changed in a way *not* explicitly requested by the PatchObject
2050 sent to the server, or null if none. This lets the client know of
2051 any changes to server-set or computed properties.
2053 This argument is null if no Foo objects were successfully updated.
2055 o destroyed: "Id[]|null"
2057 A list of Foo ids for records that were successfully destroyed, or
2060 o notCreated: "Id[SetError]|null"
2062 A map of the creation id to a SetError object for each record that
2063 failed to be created, or null if all successful.
2065 o notUpdated: "Id[SetError]|null"
2067 A map of the Foo id to a SetError object for each record that
2068 failed to be updated, or null if all successful.
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2076RFC 8620 JMAP July 2019
2079 o notDestroyed: "Id[SetError]|null"
2081 A map of the Foo id to a SetError object for each record that
2082 failed to be destroyed, or null if all successful.
2084 A *SetError* object has the following properties:
2090 o description: "String|null"
2092 A description of the error to help with debugging that includes an
2093 explanation of what the problem was. This is a non-localised
2094 string and is not intended to be shown directly to end users.
2096 The following SetError types are defined and may be returned for set
2097 operations on any record type where appropriate:
2099 o "forbidden": (create; update; destroy). The create/update/destroy
2100 would violate an ACL or other permissions policy.
2102 o "overQuota": (create; update). The create would exceed a server-
2103 defined limit on the number or total size of objects of this type.
2105 o "tooLarge": (create; update). The create/update would result in
2106 an object that exceeds a server-defined limit for the maximum size
2107 of a single object of this type.
2109 o "rateLimit": (create). Too many objects of this type have been
2110 created recently, and a server-defined rate limit has been
2111 reached. It may work if tried again later.
2113 o "notFound": (update; destroy). The id given to update/destroy
2116 o "invalidPatch": (update). The PatchObject given to update the
2117 record was not a valid patch (see the patch description).
2119 o "willDestroy": (update). The client requested that an object be
2120 both updated and destroyed in the same /set request, and the
2121 server has decided to therefore ignore the update.
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2135 o "invalidProperties": (create; update). The record given is
2136 invalid in some way. For example:
2138 * It contains properties that are invalid according to the type
2139 specification of this record type.
2141 * It contains a property that may only be set by the server
2142 (e.g., "id") and is different to the current value. Note, to
2143 allow clients to pass whole objects back, it is not an error to
2144 include a server-set property in an update as long as the value
2145 is identical to the current value on the server.
2147 * There is a reference to another record (foreign key), and the
2148 given id does not correspond to a valid record.
2150 The SetError object SHOULD also have a property called
2151 "properties" of type "String[]" that lists *all* the properties
2154 Individual methods MAY specify more specific errors for certain
2155 conditions that would otherwise result in an invalidProperties
2156 error. If the condition of one of these is met, it MUST be
2157 returned instead of the invalidProperties error.
2159 o "singleton": (create; destroy). This is a singleton type, so you
2160 cannot create another one or destroy the existing one.
2162 Other possible SetError types MAY be given in specific method
2163 descriptions. Other properties MAY also be present on the SetError
2164 object, as described in the relevant methods.
2166 The following additional errors may be returned instead of the "Foo/
2169 "requestTooLarge": The total number of objects to create, update, or
2170 destroy exceeds the maximum number the server is willing to process
2171 in a single method call.
2173 "stateMismatch": An "ifInState" argument was supplied, and it does
2174 not match the current state.
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2193 The only way to move Foo records *between* two different accounts is
2194 to copy them using the "Foo/copy" method; once the copy has
2195 succeeded, delete the original. The "onSuccessDestroyOriginal"
2196 argument allows you to try to do this in one method call; however,
2197 note that the two different actions are not atomic, so it is possible
2198 for the copy to succeed but the original not to be destroyed for some
2201 The copy is conceptually in three phases:
2203 1. Reading the current values from the "from" account.
2205 2. Writing the new copies to the other account.
2207 3. Destroying the originals in the "from" account, if requested.
2209 Data may change in between phases due to concurrent requests.
2211 The "Foo/copy" method takes the following arguments:
2213 o fromAccountId: "Id"
2215 The id of the account to copy records from.
2217 o ifFromInState: "String|null"
2219 This is a state string as returned by the "Foo/get" method. If
2220 supplied, the string must match the current state of the account
2221 referenced by the fromAccountId when reading the data to be
2222 copied; otherwise, the method will be aborted and a
2223 "stateMismatch" error returned. If null, the data will be read
2224 from the current state.
2228 The id of the account to copy records to. This MUST be different
2229 to the "fromAccountId".
2231 o ifInState: "String|null"
2233 This is a state string as returned by the "Foo/get" method. If
2234 supplied, the string must match the current state of the account
2235 referenced by the accountId; otherwise, the method will be aborted
2236 and a "stateMismatch" error returned. If null, any changes will
2237 be applied to the current state.
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2244RFC 8620 JMAP July 2019
2249 A map of the *creation id* to a Foo object. The Foo object MUST
2250 contain an "id" property, which is the id (in the fromAccount) of
2251 the record to be copied. When creating the copy, any other
2252 properties included are used instead of the current value for that
2253 property on the original.
2255 o onSuccessDestroyOriginal: "Boolean" (default: false)
2257 If true, an attempt will be made to destroy the original records
2258 that were successfully copied: after emitting the "Foo/copy"
2259 response, but before processing the next method, the server MUST
2260 make a single call to "Foo/set" to destroy the original of each
2261 successfully copied record; the output of this is added to the
2262 responses as normal, to be returned to the client.
2264 o destroyFromIfInState: "String|null"
2266 This argument is passed on as the "ifInState" argument to the
2267 implicit "Foo/set" call, if made at the end of this request to
2268 destroy the originals that were successfully copied.
2270 Each record copy is considered an atomic unit that may succeed or
2273 The response has the following arguments:
2275 o fromAccountId: "Id"
2277 The id of the account records were copied from.
2281 The id of the account records were copied to.
2283 o oldState: "String|null"
2285 The state string that would have been returned by "Foo/get" on the
2286 account records that were copied to before making the requested
2287 changes, or null if the server doesn't know what the previous
2290 o newState: "String"
2292 The state string that will now be returned by "Foo/get" on the
2293 account records were copied to.
2298Jenkins & Newman Standards Track [Page 41]
2300RFC 8620 JMAP July 2019
2303 o created: "Id[Foo]|null"
2305 A map of the creation id to an object containing any properties of
2306 the copied Foo object that are set by the server (such as the "id"
2307 in most object types; note, the id is likely to be different to
2308 the id of the object in the account it was copied from).
2310 This argument is null if no Foo objects were successfully copied.
2312 o notCreated: "Id[SetError]|null"
2314 A map of the creation id to a SetError object for each record that
2315 failed to be copied, or null if none.
2317 The SetError may be any of the standard set errors returned for a
2318 create or update. In addition, the following SetError is defined:
2320 "alreadyExists": The server forbids duplicates, and the record
2321 already exists in the target account. An "existingId" property of
2322 type "Id" MUST be included on the SetError object with the id of the
2325 The following additional errors may be returned instead of the "Foo/
2328 "fromAccountNotFound": The "fromAccountId" does not correspond to a
2331 "fromAccountNotSupportedByMethod": The "fromAccountId" given
2332 corresponds to a valid account, but the account does not support this
2335 "stateMismatch": An "ifInState" argument was supplied and it does not
2336 match the current state, or an "ifFromInState" argument was supplied
2337 and it does not match the current state in the from account.
2341 For data sets where the total amount of data is expected to be very
2342 small, clients can just fetch the complete set of data and then do
2343 any sorting/filtering locally. However, for large data sets (e.g.,
2344 multi-gigabyte mailboxes), the client needs to be able to
2345 search/sort/window the data type on the server.
2347 A query on the set of Foos in an account is made by calling "Foo/
2348 query". This takes a number of arguments to determine which records
2349 to include, how they should be sorted, and which part of the result
2354Jenkins & Newman Standards Track [Page 42]
2356RFC 8620 JMAP July 2019
2359 should be returned (the full list may be *very* long). The result is
2360 returned as a list of Foo ids.
2362 A call to "Foo/query" takes the following arguments:
2366 The id of the account to use.
2368 o filter: "FilterOperator|FilterCondition|null"
2370 Determines the set of Foos returned in the results. If null, all
2371 objects in the account of this type are included in the results.
2372 A *FilterOperator* object has the following properties:
2374 * operator: "String"
2376 This MUST be one of the following strings:
2378 + "AND": All of the conditions must match for the filter to
2381 + "OR": At least one of the conditions must match for the
2384 + "NOT": None of the conditions must match for the filter to
2387 * conditions: "(FilterOperator|FilterCondition)[]"
2389 The conditions to evaluate against each record.
2391 A *FilterCondition* is an "object" whose allowed properties and
2392 semantics depend on the data type and is defined in the /query
2393 method specification for that type. It MUST NOT have an
2394 "operator" property.
2396 o sort: "Comparator[]|null"
2398 Lists the names of properties to compare between two Foo records,
2399 and how to compare them, to determine which comes first in the
2400 sort. If two Foo records have an identical value for the first
2401 comparator, the next comparator will be considered, and so on. If
2402 all comparators are the same (this includes the case where an
2403 empty array or null is given as the "sort" argument), the sort
2404 order is server dependent, but it MUST be stable between calls to
2405 "Foo/query". A *Comparator* has the following properties:
2410Jenkins & Newman Standards Track [Page 43]
2412RFC 8620 JMAP July 2019
2415 * property: "String"
2417 The name of the property on the Foo objects to compare.
2419 * isAscending: "Boolean" (optional; default: true)
2421 If true, sort in ascending order. If false, reverse the
2422 comparator's results to sort in descending order.
2424 * collation: "String" (optional; default is server-dependent)
2426 The identifier, as registered in the collation registry defined
2427 in [RFC4790], for the algorithm to use when comparing the order
2428 of strings. The algorithms the server supports are advertised
2429 in the capabilities object returned with the Session object
2432 If omitted, the default algorithm is server dependent, but:
2434 1. It MUST be unicode-aware.
2436 2. It MAY be selected based on an Accept-Language header in
2437 the request (as defined in [RFC7231], Section 5.3.5) or
2438 out-of-band information about the user's language/locale.
2440 3. It SHOULD be case insensitive where such a concept makes
2441 sense for a language/locale. Where the user's language is
2442 unknown, it is RECOMMENDED to follow the advice in
2443 Section 5.2.3 of [RFC8264].
2445 The "i;unicode-casemap" collation [RFC5051] and the Unicode
2446 Collation Algorithm (<http://www.unicode.org/reports/tr10/>)
2447 are two examples that fulfil these criterion and provide
2448 reasonable behaviour for a large number of languages.
2450 When the property being compared is not a string, the
2451 "collation" property is ignored, and the following comparison
2452 rules apply based on the type. In ascending order:
2454 + "Boolean": false comes before true.
2456 + "Number": A lower number comes before a higher number.
2458 + "Date"/"UTCDate": The earlier date comes first.
2460 The Comparator object may also have additional properties as
2461 required for specific sort operations defined in a type's /query
2466Jenkins & Newman Standards Track [Page 44]
2468RFC 8620 JMAP July 2019
2471 o position: "Int" (default: 0)
2473 The zero-based index of the first id in the full list of results
2476 If a negative value is given, it is an offset from the end of the
2477 list. Specifically, the negative value MUST be added to the total
2478 number of results given the filter, and if still negative, it's
2479 clamped to "0". This is now the zero-based index of the first id
2482 If the index is greater than or equal to the total number of
2483 objects in the results list, then the "ids" array in the response
2484 will be empty, but this is not an error.
2488 A Foo id. If supplied, the "position" argument is ignored. The
2489 index of this id in the results will be used in combination with
2490 the "anchorOffset" argument to determine the index of the first
2491 result to return (see below for more details).
2493 o anchorOffset: "Int" (default: 0)
2495 The index of the first result to return relative to the index of
2496 the anchor, if an anchor is given. This MAY be negative. For
2497 example, "-1" means the Foo immediately preceding the anchor is
2498 the first result in the list returned (see below for more
2501 o limit: "UnsignedInt|null"
2503 The maximum number of results to return. If null, no limit
2504 presumed. The server MAY choose to enforce a maximum "limit"
2505 argument. In this case, if a greater value is given (or if it is
2506 null), the limit is clamped to the maximum; the new limit is
2507 returned with the response so the client is aware. If a negative
2508 value is given, the call MUST be rejected with an
2509 "invalidArguments" error.
2511 o calculateTotal: "Boolean" (default: false)
2513 Does the client wish to know the total number of results in the
2514 query? This may be slow and expensive for servers to calculate,
2515 particularly with complex filters, so clients should take care to
2516 only request the total when needed.
2522Jenkins & Newman Standards Track [Page 45]
2524RFC 8620 JMAP July 2019
2527 If an "anchor" argument is given, the anchor is looked for in the
2528 results after filtering and sorting. If found, the "anchorOffset" is
2529 then added to its index. If the resulting index is now negative, it
2530 is clamped to 0. This index is now used exactly as though it were
2531 supplied as the "position" argument. If the anchor is not found, the
2532 call is rejected with an "anchorNotFound" error.
2534 If an "anchor" is specified, any position argument supplied by the
2535 client MUST be ignored. If no "anchor" is supplied, any
2536 "anchorOffset" argument MUST be ignored.
2538 A client can use "anchor" instead of "position" to find the index of
2539 an id within a large set of results.
2541 The response has the following arguments:
2545 The id of the account used for the call.
2547 o queryState: "String"
2549 A string encoding the current state of the query on the server.
2550 This string MUST change if the results of the query (i.e., the
2551 matching ids and their sort order) have changed. The queryState
2552 string MAY change if something has changed on the server, which
2553 means the results may have changed but the server doesn't know for
2556 The queryState string only represents the ordered list of ids that
2557 match the particular query (including its sort/filter). There is
2558 no requirement for it to change if a property on an object
2559 matching the query changes but the query results are unaffected
2560 (indeed, it is more efficient if the queryState string does not
2561 change in this case). The queryState string only has meaning when
2562 compared to future responses to a query with the same type/sort/
2563 filter or when used with /queryChanges to fetch changes.
2565 Should a client receive back a response with a different
2566 queryState string to a previous call, it MUST either throw away
2567 the currently cached query and fetch it again (note, this does not
2568 require fetching the records again, just the list of ids) or call
2569 "Foo/queryChanges" to get the difference.
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2580RFC 8620 JMAP July 2019
2583 o canCalculateChanges: "Boolean"
2585 This is true if the server supports calling "Foo/queryChanges"
2586 with these "filter"/"sort" parameters. Note, this does not
2587 guarantee that the "Foo/queryChanges" call will succeed, as it may
2588 only be possible for a limited time afterwards due to server
2589 internal implementation details.
2591 o position: "UnsignedInt"
2593 The zero-based index of the first result in the "ids" array within
2594 the complete list of query results.
2598 The list of ids for each Foo in the query results, starting at the
2599 index given by the "position" argument of this response and
2600 continuing until it hits the end of the results or reaches the
2601 "limit" number of ids. If "position" is >= "total", this MUST be
2604 o total: "UnsignedInt" (only if requested)
2606 The total number of Foos in the results (given the "filter").
2607 This argument MUST be omitted if the "calculateTotal" request
2608 argument is not true.
2610 o limit: "UnsignedInt" (if set by the server)
2612 The limit enforced by the server on the maximum number of results
2613 to return. This is only returned if the server set a limit or
2614 used a different limit than that given in the request.
2616 The following additional errors may be returned instead of the "Foo/
2619 "anchorNotFound": An anchor argument was supplied, but it cannot be
2620 found in the results of the query.
2622 "unsupportedSort": The "sort" is syntactically valid, but it includes
2623 a property the server does not support sorting on or a collation
2624 method it does not recognise.
2626 "unsupportedFilter": The "filter" is syntactically valid, but the
2627 server cannot process it. If the filter was the result of a user's
2628 search input, the client SHOULD suggest that the user simplify their
2634Jenkins & Newman Standards Track [Page 47]
2636RFC 8620 JMAP July 2019
2641 The "Foo/queryChanges" method allows a client to efficiently update
2642 the state of a cached query to match the new state on the server. It
2643 takes the following arguments:
2647 The id of the account to use.
2649 o filter: "FilterOperator|FilterCondition|null"
2651 The filter argument that was used with "Foo/query".
2653 o sort: "Comparator[]|null"
2655 The sort argument that was used with "Foo/query".
2657 o sinceQueryState: "String"
2659 The current state of the query in the client. This is the string
2660 that was returned as the "queryState" argument in the "Foo/query"
2661 response with the same sort/filter. The server will return the
2662 changes made to the query since this state.
2664 o maxChanges: "UnsignedInt|null"
2666 The maximum number of changes to return in the response. See
2667 error descriptions below for more details.
2671 The last (highest-index) id the client currently has cached from
2672 the query results. When there are a large number of results, in a
2673 common case, the client may have only downloaded and cached a
2674 small subset from the beginning of the results. If the sort and
2675 filter are both only on immutable properties, this allows the
2676 server to omit changes after this point in the results, which can
2677 significantly increase efficiency. If they are not immutable,
2678 this argument is ignored.
2680 o calculateTotal: "Boolean" (default: false)
2682 Does the client wish to know the total number of results now in
2683 the query? This may be slow and expensive for servers to
2684 calculate, particularly with complex filters, so clients should
2685 take care to only request the total when needed.
2690Jenkins & Newman Standards Track [Page 48]
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2695 The response has the following arguments:
2699 The id of the account used for the call.
2701 o oldQueryState: "String"
2703 This is the "sinceQueryState" argument echoed back; that is, the
2704 state from which the server is returning changes.
2706 o newQueryState: "String"
2708 This is the state the query will be in after applying the set of
2709 changes to the old state.
2711 o total: "UnsignedInt" (only if requested)
2713 The total number of Foos in the results (given the "filter").
2714 This argument MUST be omitted if the "calculateTotal" request
2715 argument is not true.
2719 The "id" for every Foo that was in the query results in the old
2720 state and that is not in the results in the new state.
2722 If the server cannot calculate this exactly, the server MAY return
2723 the ids of extra Foos in addition that may have been in the old
2724 results but are not in the new results.
2726 If the sort and filter are both only on immutable properties and
2727 an "upToId" is supplied and exists in the results, any ids that
2728 were removed but have a higher index than "upToId" SHOULD be
2731 If the "filter" or "sort" includes a mutable property, the server
2732 MUST include all Foos in the current results for which this
2733 property may have changed. The position of these may have moved
2734 in the results, so they must be reinserted by the client to ensure
2735 its query cache is correct.
2746Jenkins & Newman Standards Track [Page 49]
2748RFC 8620 JMAP July 2019
2751 o added: "AddedItem[]"
2753 The id and index in the query results (in the new state) for every
2754 Foo that has been added to the results since the old state AND
2755 every Foo in the current results that was included in the
2756 "removed" array (due to a filter or sort based upon a mutable
2759 If the sort and filter are both only on immutable properties and
2760 an "upToId" is supplied and exists in the results, any ids that
2761 were added but have a higher index than "upToId" SHOULD be
2764 The array MUST be sorted in order of index, with the lowest index
2767 An *AddedItem* object has the following properties:
2771 * index: "UnsignedInt"
2773 The result of this is that if the client has a cached sparse array of
2774 Foo ids corresponding to the results in the old state, then:
2776 fooIds = [ "id1", "id2", null, null, "id3", "id4", null, null, null ]
2778 If it *splices out* all ids in the removed array that it has in its
2779 cached results, then:
2781 removed = [ "id2", "id31", ... ];
2782 fooIds => [ "id1", null, null, "id3", "id4", null, null, null ]
2784 and *splices in* (one by one in order, starting with the lowest
2785 index) all of the ids in the added array:
2787 added = [{ id: "id5", index: 0, ... }];
2788 fooIds => [ "id5", "id1", null, null, "id3", "id4", null, null, null ]
2790 and *truncates* or *extends* to the new total length, then the
2791 results will now be in the new state.
2793 Note: splicing in adds the item at the given index, incrementing the
2794 index of all items previously at that or a higher index. Splicing
2795 out is the inverse, removing the item and decrementing the index of
2796 every item after it in the array.
2802Jenkins & Newman Standards Track [Page 50]
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2807 The following additional errors may be returned instead of the "Foo/
2808 queryChanges" response:
2810 "tooManyChanges": There are more changes than the client's
2811 "maxChanges" argument. Each item in the removed or added array is
2812 considered to be one change. The client may retry with higher max
2813 changes or invalidate its cache of the query results.
2815 "cannotCalculateChanges": The server cannot calculate the changes
2816 from the queryState string given by the client, usually due to the
2817 client's state being too old. The client MUST invalidate its cache
2818 of the query results.
2822 Suppose we have a type *Todo* with the following properties:
2824 o id: "Id" (immutable; server-set)
2826 The id of the object.
2830 A brief summary of what is to be done.
2832 o keywords: "String[Boolean]" (default: {})
2834 A set of keywords that apply to the Todo. The set is represented
2835 as an object, with the keys being the "keywords". The value for
2836 each key in the object MUST be true. (This format allows you to
2837 update an individual key using patch syntax rather than having to
2838 update the whole set of keywords as one, which a "String[]"
2839 representation would require.)
2841 o neuralNetworkTimeEstimation: "Number" (server-set)
2843 The title and keywords are fed into the server's state-of-the-art
2844 neural network to get an estimation of how long this Todo will
2847 o subTodoIds: "Id[]|null"
2849 The ids of a list of other Todos to complete as part of this Todo.
2851 Suppose also that all the standard methods are defined for this type
2852 and the FilterCondition object supports a "hasKeyword" property to
2853 match Todos with the given keyword.
2858Jenkins & Newman Standards Track [Page 51]
2860RFC 8620 JMAP July 2019
2863 A client might want to display the list of Todos with either a
2864 "music" keyword or a "video" keyword, so it makes the following
2872 { "hasKeyword": "music" },
2873 { "hasKeyword": "video" }
2876 "sort": [{ "property": "title" }],
2884 "name": "Todo/query",
2914Jenkins & Newman Standards Track [Page 52]
2916RFC 8620 JMAP July 2019
2919 This would query the server for the set of Todos with a keyword of
2920 either "music" or "video", sorted by title, and limited to the first
2921 10 results. It fetches the full object for each of these Todos using
2922 back-references to reference the result of the query. The response
2923 might look something like:
2927 "queryState": "y13213",
2928 "canCalculateChanges": true,
2930 "ids": [ "a", "b", "c", "d", "e", "f", "g", "h", "i", "j" ]
2937 "title": "Practise Piano",
2945 "neuralNetworkTimeEstimation": 3600
2948 "title": "Watch Daft Punk music video",
2954 "neuralNetworkTimeEstimation": 18000
2970Jenkins & Newman Standards Track [Page 53]
2972RFC 8620 JMAP July 2019
2975 Now, suppose the user adds a keyword "chopin" and removes the keyword
2976 "mozart" from the "Practise Piano" task. The client may send the
2977 whole object to the server, as this is a valid PatchObject:
2981 "ifInState": "10324",
2985 "title": "Practise Piano",
2993 "neuralNetworkTimeEstimation": 360
2998 or it may send a minimal patch:
3002 "ifInState": "10324",
3005 "keywords/chopin": true,
3006 "keywords/mozart": null
3026Jenkins & Newman Standards Track [Page 54]
3028RFC 8620 JMAP July 2019
3031 The effect is exactly the same on the server in either case, and
3032 presuming the server is still in state "10324", it will probably
3037 "oldState": "10324",
3038 "newState": "10329",
3041 "neuralNetworkTimeEstimation": 5400
3046 The server changed the "neuralNetworkTimeEstimation" property on the
3047 object as part of this change; as this changed in a way *not*
3048 explicitly requested by the PatchObject sent to the server, it is
3049 returned with the "updated" confirmation.
3051 Let us now add a sub-Todo to our new "Practise Piano" Todo. In this
3052 example, we can see the use of a reference to a creation id to allow
3053 us to set a foreign key reference to a record created in the same
3060 "title": "Warm up with scales"
3065 "subTodoIds": [ "#k15" ]
3082Jenkins & Newman Standards Track [Page 55]
3084RFC 8620 JMAP July 2019
3087 Now, suppose another user deleted the "Listen to Daft Punk" Todo.
3088 The first user will receive a push notification (see Section 7) with
3089 the changed state string for the "Todo" type. Since the new string
3090 does not match its current state, it knows it needs to check for
3091 updates. It may make a request like:
3093 [[ "Todo/changes", {
3095 "sinceState": "10324",
3098 [ "Todo/queryChanges", {
3103 { "hasKeyword": "music" },
3104 { "hasKeyword": "video" }
3107 "sort": [{ "property": "title" }],
3108 "sinceQueryState": "y13213",
3112 and receive in response:
3114 [[ "Todo/changes", {
3116 "oldState": "10324",
3117 "newState": "871903",
3118 "hasMoreChanges": false,
3123 [ "Todo/queryChanges", {
3125 "oldQueryState": "y13213",
3126 "newQueryState": "y13218",
3138Jenkins & Newman Standards Track [Page 56]
3140RFC 8620 JMAP July 2019
3143 Suppose the user has access to another account "y", for example, a
3144 team account shared between multiple users. To move an existing Todo
3145 from account "x", the client would call:
3148 "fromAccountId": "x",
3155 "onSuccessDestroyOriginal": true
3158 The server successfully copies the Todo to a new account (where it
3159 receives a new id) and deletes the original. Due to the implicit
3160 call to "Todo/set", there are two responses to the single method
3161 call, both with the same method call id:
3164 "fromAccountId": "x",
3171 "oldState": "c1d64ecb038c",
3172 "newState": "33844835152b"
3176 "oldState": "871903",
3177 "newState": "871909",
3178 "destroyed": [ "a" ],
3194Jenkins & Newman Standards Track [Page 57]
3196RFC 8620 JMAP July 2019
31995.8. Proxy Considerations
3201 JMAP has been designed to allow an API endpoint to easily proxy
3202 through to one or more JMAP servers. This may be useful for load
3203 balancing, augmenting capabilities, or presenting a single endpoint
3204 to accounts hosted on different JMAP servers (splitting the request
3205 based on each method's "accountId" argument). The proxy need only
3206 understand the general structure of a JMAP Request object; it does
3207 not need to know anything specifically about the methods and
3208 arguments it will pass through to other servers.
3210 If splitting up the methods in a request to call them on different
3211 backend servers, the proxy must do two things to ensure back-
3212 references and creation-id references resolve the same as if the
3213 entire request were processed on a single server:
3215 1. It must pass a "createdIds" property with each subrequest. If
3216 this is not given by the client, an empty object should be used
3217 for the first subrequest. The "createdIds" property of each
3218 subresponse should be passed on in the next subrequest.
3220 2. It must resolve back-references to previous method results that
3221 were processed on a different server. This is a relatively
3222 simple syntactic substitution, described in Section 3.7.
3224 When splitting a request based on accountId, proxy implementors do
3225 need to be aware of "/copy" methods that copy between accounts. If
3226 the accounts are on different servers, the proxy will have to
3227 implement this functionality directly.
3231 Binary data is referenced by a *blobId* in JMAP and uploaded/
3232 downloaded separately to the core API. The blobId solely represents
3233 the raw bytes of data, not any associated metadata such as a file
3234 name or content type. Such metadata is stored alongside the blobId
3235 in the object referencing it. The data represented by a blobId is
3238 Any blobId that exists within an account may be used when creating/
3239 updating another object in that account. For example, an Email type
3240 may have a blobId that represents the object in Internet Message
3241 Format [RFC5322]. A client could create a new Email object with an
3242 attachment and use this blobId, in effect attaching the old message
3243 to the new one. Similarly, it could attach any existing attachment
3244 of an old message without having to download and upload it again.
3250Jenkins & Newman Standards Track [Page 58]
3252RFC 8620 JMAP July 2019
3255 When the client uses a blobId in a create/update, the server MAY
3256 assign a new blobId to refer to the same binary data within the new/
3257 updated object. If it does so, it MUST return any properties that
3258 contain a changed blobId in the created/updated response, so the
3259 client gets the new ids.
3261 A blob that is not referenced by a JMAP object (e.g., as a message
3262 attachment) MAY be deleted by the server to free up resources.
3263 Uploads (see below) are initially unreferenced blobs. To ensure
3266 o The server SHOULD use a separate quota for unreferenced blobs to
3267 the account's usual quota. In the case of shared accounts, this
3268 quota SHOULD be separate per user.
3270 o This quota SHOULD be at least the maximum total size that a single
3271 object can reference on this server. For example, if supporting
3272 JMAP Mail, this should be at least the maximum total attachments
3275 o When an upload would take the user over quota, the server MUST
3276 delete unreferenced blobs in date order, oldest first, until there
3277 is room for the new blob.
3279 o Except where quota restrictions force early deletion, an
3280 unreferenced blob MUST NOT be deleted for at least 1 hour from the
3281 time of upload; if reuploaded, the same blobId MAY be returned,
3282 but this SHOULD reset the expiry time.
3284 o A blob MUST NOT be deleted during the method call that removed the
3285 last reference, so that a client can issue a create and a destroy
3286 that both reference the blob within the same method call.
32886.1. Uploading Binary Data
3290 There is a single endpoint that handles all file uploads for an
3291 account, regardless of what they are to be used for. The Session
3292 object (see Section 2) has an "uploadUrl" property in URI Template
3293 (level 1) format [RFC6570], which MUST contain a variable called
3294 "accountId". The client may use this template in combination with an
3295 "accountId" to get the URL of the file upload resource.
3297 To upload a file, the client submits an authenticated POST request to
3298 the file upload resource.
3306Jenkins & Newman Standards Track [Page 59]
3308RFC 8620 JMAP July 2019
3311 A successful request MUST return a single JSON object with the
3312 following properties as the response:
3316 The id of the account used for the call.
3320 The id representing the binary data uploaded. The data for this
3321 id is immutable. The id *only* refers to the binary data, not any
3326 The media type of the file (as specified in [RFC6838],
3327 Section 4.2) as set in the Content-Type header of the upload HTTP
3330 o size: "UnsignedInt"
3332 The size of the file in octets.
3334 If identical binary content to an existing blob in the account is
3335 uploaded, the existing blobId MAY be returned.
3337 Clients should use the blobId returned in a timely manner. Under
3338 rare circumstances, the server may have deleted the blob before the
3339 client uses it; the client should keep a reference to the local file
3340 so it can upload it again in such a situation.
3342 When an HTTP error response is returned to the client, the server
3343 SHOULD return a JSON "problem details" object as the response body,
3346 As access controls are often determined by the object holding the
3347 reference to a blob, unreferenced blobs MUST only be accessible to
3348 the uploader, even in shared accounts.
33506.2. Downloading Binary Data
3352 The Session object (see Section 2) has a "downloadUrl" property,
3353 which is in URI Template (level 1) format [RFC6570]. The URL MUST
3354 contain variables called "accountId", "blobId", "type", and "name".
3362Jenkins & Newman Standards Track [Page 60]
3364RFC 8620 JMAP July 2019
3367 To download a file, the client makes an authenticated GET request to
3368 the download URL with the appropriate variables substituted in:
3370 o "accountId": The id of the account to which the record with the
3373 o "blobId": The blobId representing the data of the file to
3376 o "type": The type for the server to set in the "Content-Type"
3377 header of the response; the blobId only represents the binary data
3378 and does not have a content-type innately associated with it.
3380 o "name": The name for the file; the server MUST return this as the
3381 filename if it sets a "Content-Disposition" header.
3383 As the data for a particular blobId is immutable, and thus the
3384 response in the generated download URL is too, implementors are
3385 recommended to set long cache times and use the "immutable" Cache-
3386 Control extension [RFC8246] for successful responses, for example,
3387 "Cache-Control: private, immutable, max-age=31536000".
3389 When an HTTP error response is returned to the client, the server
3390 SHOULD return a JSON "problem details" object as the response body,
3395 Binary data may be copied *between* two different accounts using the
3396 "Blob/copy" method rather than having to download and then reupload
3399 The "Blob/copy" method takes the following arguments:
3401 o fromAccountId: "Id"
3403 The id of the account to copy blobs from.
3407 The id of the account to copy blobs to.
3411 A list of ids of blobs to copy to the other account.
3418Jenkins & Newman Standards Track [Page 61]
3420RFC 8620 JMAP July 2019
3423 The response has the following arguments:
3425 o fromAccountId: "Id"
3427 The id of the account blobs were copied from.
3431 The id of the account blobs were copied to.
3433 o copied: "Id[Id]|null"
3435 A map of the blobId in the fromAccount to the id for the blob in
3436 the account it was copied to, or null if none were successfully
3439 o notCopied: "Id[SetError]|null"
3441 A map of blobId to a SetError object for each blob that failed to
3442 be copied, or null if none.
3444 The SetError may be any of the standard set errors that may be
3445 returned for a create, as defined in Section 5.3. In addition, the
3446 "notFound" SetError error may be returned if the blobId to be copied
3449 The following additional method-level error may be returned instead
3450 of the "Blob/copy" response:
3452 "fromAccountNotFound": The "fromAccountId" included with the request
3453 does not correspond to a valid account.
3457 Push notifications allow clients to efficiently update (almost)
3458 instantly to stay in sync with data changes on the server. The
3459 general model for push is simple and sends minimal data over the push
3460 channel: just enough for the client to know whether it needs to
3461 resync. The format allows multiple changes to be coalesced into a
3462 single push update and the frequency of pushes to be rate limited by
3463 the server. It doesn't matter if some push events are dropped before
3464 they reach the client; the next time it gets/sets any records of a
3465 changed type, it will discover the data has changed and still sync
3474Jenkins & Newman Standards Track [Page 62]
3476RFC 8620 JMAP July 2019
3479 There are two different mechanisms by which a client can receive push
3480 notifications, to allow for the different environments in which a
3481 client may exist. An event source resource (see Section 7.3) allows
3482 clients that can hold transport connections open to receive push
3483 notifications directly from the JMAP server. This is simple and
3484 avoids third parties, but it is often not feasible on constrained
3485 platforms such as mobile devices. Alternatively, clients can make
3486 use of any push service supported by their environment. A URL for
3487 the push service is registered with the JMAP server (see
3488 Section 7.2); the server then POSTs each notification to that URL.
3489 The push service is then responsible for routing these to the client.
34917.1. The StateChange Object
3493 When something changes on the server, the server pushes a StateChange
3494 object to the client. A *StateChange* object has the following
3499 This MUST be the string "StateChange".
3501 o changed: "Id[TypeState]"
3503 A map of an "account id" to an object encoding the state of data
3504 types that have changed for that account since the last
3505 StateChange object was pushed, for each of the accounts to which
3506 the user has access and for which something has changed.
3508 A *TypeState* object is a map. The keys are the type name "Foo"
3509 (e.g., "Mailbox" or "Email"), and the value is the "state"
3510 property that would currently be returned by a call to "Foo/get".
3512 The client can compare the new state strings with its current
3513 values to see whether it has the current data for these types. If
3514 not, the changes can then be efficiently fetched in a single
3515 standard API request (using the /changes type methods).
3530Jenkins & Newman Standards Track [Page 63]
3532RFC 8620 JMAP July 2019
3537 In this example, the server has amalgamated a few changes together
3538 across two different accounts the user has access to, before pushing
3539 the following StateChange object to the client:
3542 "@type": "StateChange",
3545 "Email": "d35ecb040aab",
3546 "EmailDelivery": "428d565f2440",
3547 "CalendarEvent": "87accfac587a"
3550 "Mailbox": "0af7a512ce70",
3551 "CalendarEvent": "7a4297cecd76"
3556 The client can compare the state strings with its current state for
3557 the Email, CalendarEvent, etc., object types in the appropriate
3558 accounts to see if it needs to fetch changes.
3560 If the client is itself making changes, it may receive a StateChange
3561 object while the /set API call is in flight. It can wait until the
3562 call completes and then compare if the new state string after the
3563 /set is the same as was pushed in the StateChange object; if so, and
3564 the old state of the /set response matches the client's previous
3565 state, it does not need to waste a request asking for changes it
35687.2. PushSubscription
3570 Clients may create a PushSubscription to register a URL with the JMAP
3571 server. The JMAP server will then make an HTTP POST request to this
3572 URL for each push notification it wishes to send to the client.
3574 As a push subscription causes the JMAP server to make a number of
3575 requests to a previously unknown endpoint, it can be used as a vector
3576 for launching a denial-of-service attack. To prevent this, when a
3577 subscription is created, the JMAP server immediately sends a
3578 PushVerification object to that URL (see Section 7.2.2). The JMAP
3579 server MUST NOT make any further requests to the URL until the client
3580 receives the push and updates the subscription with the correct
3586Jenkins & Newman Standards Track [Page 64]
3588RFC 8620 JMAP July 2019
3591 A *PushSubscription* object has the following properties:
3593 o id: "Id" (immutable; server-set)
3595 The id of the push subscription.
3597 o deviceClientId: "String" (immutable)
3599 An id that uniquely identifies the client + device it is running
3600 on. The purpose of this is to allow clients to identify which
3601 PushSubscription objects they created even if they lose their
3602 local state, so they can revoke or update them. This string MUST
3603 be different on different devices and be different from apps from
3604 other vendors. It SHOULD be easy to regenerate and not depend on
3605 persisted state. It is RECOMMENDED to use a secure hash of a
3606 string that contains:
3608 1. A unique identifier associated with the device where the JMAP
3609 client is running, normally supplied by the device's operating
3612 2. A custom vendor/app id, including a domain controlled by the
3613 vendor of the JMAP client.
3615 To protect the privacy of the user, the deviceClientId id MUST NOT
3616 contain an unobfuscated device id.
3618 o url: "String" (immutable)
3620 An absolute URL where the JMAP server will POST the data for the
3621 push message. This MUST begin with "https://".
3623 o keys: "Object|null" (immutable)
3625 Client-generated encryption keys. If supplied, the server MUST
3626 use them as specified in [RFC8291] to encrypt all data sent to the
3627 push subscription. The object MUST have the following properties:
3631 The P-256 Elliptic Curve Diffie-Hellman (ECDH) public key as
3632 described in [RFC8291], encoded in URL-safe base64
3633 representation as defined in [RFC4648].
3637 The authentication secret as described in [RFC8291], encoded in
3638 URL-safe base64 representation as defined in [RFC4648].
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3644RFC 8620 JMAP July 2019
3647 o verificationCode: "String|null"
3649 This MUST be null (or omitted) when the subscription is created.
3650 The JMAP server then generates a verification code and sends it in
3651 a push message, and the client updates the PushSubscription object
3652 with the code; see Section 7.2.2 for details.
3654 o expires: "UTCDate|null"
3656 The time this push subscription expires. If specified, the JMAP
3657 server MUST NOT make further requests to this resource after this
3658 time. It MAY automatically destroy the push subscription at or
3661 The server MAY choose to set an expiry if none is given by the
3662 client or modify the expiry time given by the client to a shorter
3665 o types: "String[]|null"
3667 A list of types the client is interested in (using the same names
3668 as the keys in the TypeState object defined in the previous
3669 section). A StateChange notification will only be sent if the
3670 data for one of these types changes. Other types are omitted from
3671 the TypeState object. If null, changes will be pushed for all
3674 The POST request MUST have a content type of "application/json" and
3675 contain the UTF-8 JSON-encoded object as the body. The request MUST
3676 have a "TTL" header and MAY have "Urgency" and/or "Topic" headers, as
3677 specified in Section 5 of [RFC8030]. The JMAP server is expected to
3678 understand and handle HTTP status responses in a reasonable manner.
3679 A "429" (Too Many Requests) response MUST cause the JMAP server to
3680 reduce the frequency of pushes; the JMAP push structure allows
3681 multiple changes to be coalesced into a single minimal StateChange
3682 object. See the security considerations in Section 8.6 for a
3683 discussion of the risks in connecting to unknown servers.
3685 The JMAP server acts as an application server as defined in
3686 [RFC8030]. A client MAY use the rest of [RFC8030] in combination
3687 with its own push service to form a complete end-to-end solution, or
3688 it MAY rely on alternative mechanisms to ensure the delivery of the
3689 pushed data after it leaves the JMAP server.
3691 The push subscription is tied to the credentials used to authenticate
3692 the API request that created it. Should these credentials expire or
3693 be revoked, the push subscription MUST be destroyed by the JMAP
3698Jenkins & Newman Standards Track [Page 66]
3700RFC 8620 JMAP July 2019
3703 server. Only subscriptions created by these credentials are returned
3704 when the client fetches existing subscriptions.
3706 When these credentials have their own expiry (i.e., it is a session
3707 with a timeout), the server SHOULD NOT set or bound the expiry time
3708 for the push subscription given by the client but MUST expire it when
3709 the session expires.
3711 When these credentials are not time bounded (e.g., Basic
3712 authentication [RFC7617]), the server SHOULD set an expiry time for
3713 the push subscription if none is given and limit the expiry time if
3714 set too far in the future. This maximum expiry time MUST be at least
3715 48 hours in the future and SHOULD be at least 7 days in the future.
3716 An app running on a mobile device may only be able to refresh the
3717 push subscription lifetime when it is in the foreground, so this
3718 gives a reasonable time frame to allow this to happen.
3720 In the case of separate access and refresh credentials, as in Oauth
3721 2.0 [RFC6749], the server SHOULD tie the push subscription to the
3722 validity of the refresh token rather than the access token and behave
3723 according to whether this is time-limited or not.
3725 When a push subscription is destroyed, the server MUST securely erase
3726 the URL and encryption keys from memory and storage as soon as
37297.2.1. PushSubscription/get
3731 Standard /get method as described in Section 5.1, except it does
3732 *not* take or return an "accountId" argument, as push subscriptions
3733 are not tied to specific accounts. It also does *not* return a
3734 "state" argument. The "ids" argument may be null to fetch all at
3737 The server MUST only return push subscriptions that were created
3738 using the same authentication credentials as for this
3739 "PushSubscription/get" request.
3741 As the "url" and "keys" properties may contain data that is private
3742 to a particular device, the values for these properties MUST NOT be
3743 returned. If the "properties" argument is null or omitted, the
3744 server MUST default to all properties excluding these two. If one of
3745 them is explicitly requested, the method call MUST be rejected with a
3754Jenkins & Newman Standards Track [Page 67]
3756RFC 8620 JMAP July 2019
37597.2.2. PushSubscription/set
3761 Standard /set method as described in Section 5.3, except it does
3762 *not* take or return an "accountId" argument, as push subscriptions
3763 are not tied to specific accounts. It also does *not* take an
3764 "ifInState" argument or return "oldState" or "newState" arguments.
3766 The "url" and "keys" properties are immutable; if the client wishes
3767 to change these, it must destroy the current push subscription and
3770 When a PushSubscription is created, the server MUST immediately push
3771 a *PushVerification* object to the URL. It has the following
3776 This MUST be the string "PushVerification".
3778 o pushSubscriptionId: "String"
3780 The id of the push subscription that was created.
3782 o verificationCode: "String"
3784 The verification code to add to the push subscription. This MUST
3785 contain sufficient entropy to avoid the client being able to guess
3786 the code via brute force.
3788 The client MUST update the push subscription with the correct
3789 verification code before the server makes any further requests to the
3790 subscription's URL. Attempts to update the subscription with an
3791 invalid verification code MUST be rejected by the server with an
3792 "invalidProperties" SetError.
3794 The client may update the "expires" property to extend (or, less
3795 commonly, shorten) the lifetime of a push subscription. The server
3796 MAY modify the proposed new expiry time to enforce server-defined
3797 limits. Extending the lifetime does not require the subscription to
3800 Clients SHOULD NOT update or destroy a push subscription that they
3801 did not create (i.e., has a "deviceClientId" that they do not
3810Jenkins & Newman Standards Track [Page 68]
3812RFC 8620 JMAP July 2019
3817 At "2018-07-06T02:14:29Z", a client with deviceClientId "a889-ffea-
3818 910" fetches the set of push subscriptions currently on the server,
3819 making an API request with:
3821 [[ "PushSubscription/get", {
3827 [[ "PushSubscription/get", {
3829 "id": "e50b2c1d-9553-41a3-b0a7-a7d26b599ee1",
3830 "deviceClientId": "b37ff8001ca0",
3831 "verificationCode": "b210ef734fe5f439c1ca386421359f7b",
3832 "expires": "2018-07-31T00:13:21Z",
3835 "id": "f2d0aab5-e976-4e8b-ad4b-b380a5b987e4",
3836 "deviceClientId": "X8980fc",
3837 "verificationCode": "f3d4618a9ae15c8b7f5582533786d531",
3838 "expires": "2018-07-12T05:55:00Z",
3839 "types": [ "Mailbox", "Email", "EmailDelivery" ]
3844 Since neither of the returned push subscription objects have the
3845 client's deviceClientId, it knows it does not have a current push
3846 subscription active on the server. So it creates one, sending this
3849[[ "PushSubscription/set", {
3852 "deviceClientId": "a889-ffea-910",
3853 "url": "https://example.com/push/?device=X8980fc&client=12c6d086",
3866Jenkins & Newman Standards Track [Page 69]
3868RFC 8620 JMAP July 2019
3871 The server creates the push subscription but limits the expiry time
3872 to 7 days in the future, returning this response:
3874 [[ "PushSubscription/set", {
3877 "id": "P43dcfa4-1dd4-41ef-9156-2c89b3b19c60",
3879 "expires": "2018-07-13T02:14:29Z"
3884 The server also immediately makes a POST request to
3885 "https://example.com/push/?device=X8980fc&client=12c6d086" with the
3889 "@type": "PushVerification",
3890 "pushSubscriptionId": "P43dcfa4-1dd4-41ef-9156-2c89b3b19c60",
3891 "verificationCode": "da1f097b11ca17f06424e30bf02bfa67"
3894 The client receives this and updates the subscription with the
3895 verification code (note there is a potential race condition here; the
3896 client MUST be able to handle receiving the push while the request
3897 creating the subscription is still in progress):
3899 [[ "PushSubscription/set", {
3901 "P43dcfa4-1dd4-41ef-9156-2c89b3b19c60": {
3902 "verificationCode": "da1f097b11ca17f06424e30bf02bfa67"
3907 The server confirms the update was successful and will now make
3908 requests to the registered URL when the state changes.
3922Jenkins & Newman Standards Track [Page 70]
3924RFC 8620 JMAP July 2019
3927 Two days later, the client updates the subscription to extend its
3928 lifetime, sending this request:
3930 [[ "PushSubscription/set", {
3932 "P43dcfa4-1dd4-41ef-9156-2c89b3b19c60": {
3933 "expires": "2018-08-13T00:00:00Z"
3938 The server extends the expiry time, but only again to its maximum
3939 limit of 7 days in the future, returning this response:
3941 [[ "PushSubscription/set", {
3943 "P43dcfa4-1dd4-41ef-9156-2c89b3b19c60": {
3944 "expires": "2018-07-15T02:22:50Z"
3951 Clients that can hold transport connections open can connect directly
3952 to the JMAP server to receive push notifications via a "text/event-
3953 stream" resource, as described in [EventSource]. This is a long
3954 running HTTP request, where the server can push data to the client by
3955 appending data without ending the response.
3957 When a change occurs in the data on the server, it pushes an event
3958 called "state" to any connected clients, with the StateChange object
3961 The server SHOULD also send a new event id that encodes the entire
3962 server state visible to the user immediately after sending a "state"
3963 event. When a new connection is made to the event-source endpoint, a
3964 client following the server-sent events specification will send a
3965 Last-Event-ID HTTP header field with the last id it saw, which the
3966 server can use to work out whether the client has missed some
3967 changes. If so, it SHOULD send these changes immediately on
3970 The Session object (see Section 2) has an "eventSourceUrl" property,
3971 which is in URI Template (level 1) format [RFC6570]. The URL MUST
3972 contain variables called "types", "closeafter", and "ping".
3978Jenkins & Newman Standards Track [Page 71]
3980RFC 8620 JMAP July 2019
3983 To connect to the resource, the client makes an authenticated GET
3984 request to the event-source URL with the appropriate variables
3987 o "types": This MUST be either:
3989 * A comma-separated list of type names, e.g.,
3990 "Email,CalendarEvent". The server MUST only push changes for
3991 the types in this list.
3993 * The single character: "*". Changes to all types are pushed.
3995 o "closeafter": This MUST be one of the following values:
3997 * "state": The server MUST end the HTTP response after pushing a
3998 state event. This can be used by clients in environments where
3999 buffering proxies prevent the pushed data from arriving
4000 immediately, or indeed at all, when operating in the usual
4003 * "no": The connection is persisted by the server as a standard
4004 event-source resource.
4006 o "ping": A positive integer value representing a length of time in
4007 seconds, e.g., "300". If non-zero, the server MUST send an event
4008 called "ping" whenever this time elapses since the previous event
4009 was sent. This MUST NOT set a new event id. If the value is "0",
4010 the server MUST NOT send ping events.
4012 The server MAY modify a requested ping interval to be subject to a
4013 minimum and/or maximum value. For interoperability, servers MUST
4014 NOT have a minimum allowed value higher than 30 or a maximum
4015 allowed value less than 300.
4017 The data for the ping event MUST be a JSON object containing an
4018 "interval" property, the value (type "UnsignedInt") being the
4019 interval in seconds the server is using to send pings (this may be
4020 different to the requested value if the server clamped it to be
4021 within a min/max value).
4023 Clients can monitor for the ping event to help determine when the
4024 closeafter mode may be required.
4026 A client MAY hold open multiple connections to the event-source
4027 resource, although it SHOULD try to use a single connection for
4034Jenkins & Newman Standards Track [Page 72]
4036RFC 8620 JMAP July 2019
40398. Security Considerations
40418.1. Transport Confidentiality
4043 To ensure the confidentiality and integrity of data sent and received
4044 via JMAP, all requests MUST use TLS 1.2 [RFC5246] [RFC8446] or later,
4045 following the recommendations in [RFC7525]. Servers SHOULD support
4046 TLS 1.3 [RFC8446] or later.
4048 Clients MUST validate TLS certificate chains to protect against
4049 man-in-the-middle attacks [RFC5280].
40518.2. Authentication Scheme
4053 A number of HTTP authentication schemes have been standardised (see
4054 <https://www.iana.org/assignments/http-authschemes/>). Servers
4055 should take care to assess the security characteristics of different
4056 schemes in relation to their needs when deciding what to implement.
4058 Use of the Basic authentication scheme is NOT RECOMMENDED. Services
4059 that choose to use it are strongly recommended to require generation
4060 of a unique "app password" via some external mechanism for each
4061 client they wish to connect. This allows connections from different
4062 devices to be differentiated by the server and access to be
4063 individually revoked.
40658.3. Service Autodiscovery
4067 Unless secured by something like DNSSEC, autodiscovery of server
4068 details using SRV DNS records is vulnerable to a DNS poisoning
4069 attack, which can lead to the client talking to an attacker's server
4070 instead of the real JMAP server. The attacker may then intercept
4071 requests to execute man-in-the-middle attacks and, depending on the
4072 authentication scheme, steal credentials to generate its own
4075 Clients that do not support SRV lookups are likely to try just using
4076 the "/.well-known/jmap" path directly against the domain of the
4077 username over HTTPS. Servers SHOULD ensure this path resolves or
4078 redirects to the correct JMAP Session resource to allow this to work.
4079 If this is not feasible, servers MUST ensure this path cannot be
4080 controlled by an attacker, as again it may be used to steal
4090Jenkins & Newman Standards Track [Page 73]
4092RFC 8620 JMAP July 2019
4097 The Security Considerations of [RFC8259] apply to the use of JSON as
4098 the data interchange format.
4100 As for any serialization format, parsers need to thoroughly check the
4101 syntax of the supplied data. JSON uses opening and closing tags for
4102 several types and structures, and it is possible that the end of the
4103 supplied data will be reached when scanning for a matching closing
4104 tag; this is an error condition, and implementations need to stop
4105 scanning at the end of the supplied data.
4107 JSON also uses a string encoding with some escape sequences to encode
4108 special characters within a string. Care is needed when processing
4109 these escape sequences to ensure that they are fully formed before
4110 the special processing is triggered, with special care taken when the
4111 escape sequences appear adjacent to other (non-escaped) special
4112 characters or adjacent to the end of data (as in the previous
4115 If parsing JSON into a non-textual structured data format,
4116 implementations may need to allocate storage to hold JSON string
4117 elements. Since JSON does not use explicit string lengths, the risk
4118 of denial of service due to resource exhaustion is small, but
4119 implementations may still wish to place limits on the size of
4120 allocations they are willing to make in any given context, to avoid
4121 untrusted data causing excessive memory allocation.
41238.5. Denial of Service
4125 A small request may result in a very large response and require
4126 considerable work on the server if resource limits are not enforced.
4127 JMAP provides mechanisms for advertising and enforcing a wide variety
4128 of limits for mitigating this threat, including limits on the number
4129 of objects fetched in a single method call, number of methods in a
4130 single request, number of concurrent requests, etc.
4132 JMAP servers MUST implement sensible limits to mitigate against
4133 resource exhaustion attacks.
41358.6. Connection to Unknown Push Server
4137 When a push subscription is registered, the application server will
4138 make POST requests to the given URL. There are a number of security
4139 considerations that MUST be considered when implementing this.
4146Jenkins & Newman Standards Track [Page 74]
4148RFC 8620 JMAP July 2019
4151 The server MUST ensure the URL is externally resolvable to avoid
4152 server-side request forgery, where the server makes a request to a
4153 resource on its internal network.
4155 A malicious client may use the push subscription to attempt to flood
4156 a third party server with requests, creating a denial-of-service
4157 attack and masking the attacker's true identity. There is no
4158 guarantee that the URL given to the JMAP server is actually a valid
4159 push server. Upon creation of a push subscription, the JMAP server
4160 sends a PushVerification object to the URL and MUST NOT send any
4161 further requests until the client verifies it has received the
4162 initial push. The verification code MUST contain sufficient entropy
4163 to prevent the client from being able to verify the subscription via
4166 The verification code does not guarantee the URL is a valid push
4167 server, only that the client is able to access the data submitted to
4168 it. While the verification step significantly reduces the set of
4169 potential targets, there is still a risk that the server is unrelated
4170 to the client and being targeted for a denial-of-service attack.
4172 The server MUST limit the number of push subscriptions any one user
4173 may have to ensure the user cannot cause the server to send a large
4174 number of push notifications at once, which could again be used as
4175 part of a denial-of-service attack. The rate of creation MUST also
4176 be limited to minimise the ability to abuse the verification request
4177 as an attack vector.
4181 When data changes, a small object is pushed with the new state
4182 strings for the types that have changed. While the data here is
4183 minimal, a passive man-in-the-middle attacker may be able to gain
4184 useful information. To ensure confidentiality and integrity, if the
4185 push is sent via a third party outside of the control of the client
4186 and JMAP server, the client MUST specify encryption keys when
4187 establishing the PushSubscription and ignore any push notification
4188 received that is not encrypted with those keys.
4190 The privacy and security considerations of [RFC8030] and [RFC8291]
4191 also apply to the use of the PushSubscription mechanism.
4193 As there is no crypto algorithm agility in Web Push Encryption
4194 [RFC8291], a new specification will be needed to provide this if new
4195 algorithms are required in the future.
4202Jenkins & Newman Standards Track [Page 75]
4204RFC 8620 JMAP July 2019
42078.8. Traffic Analysis
4209 While the data is encrypted, a passive observer with the ability to
4210 monitor network traffic may be able to glean information from the
4211 timing of API requests and push notifications. For example, suppose
4212 an email or calendar invitation is sent from User A (hosted on Server
4213 X) to User B (hosted on Server Y). If Server X hosts data for many
4214 users, a passive observer can see that the two servers connected but
4215 does not know who the data was for. However, if a push notification
4216 is immediately sent to User B and the attacker can observe this as
4217 well, they may reasonably conclude that someone on Server X is
4218 connecting to User B.
42209. IANA Considerations
42229.1. Assignment of jmap Service Name
4224 IANA has assigned the 'jmap' service name in the "Service Name and
4225 Transport Protocol Port Number Registry" [RFC6335].
4229 Transport Protocol(s): tcp
4235 Description: JSON Meta Application Protocol
4239 Assignment Notes: This service name was previously assigned under the
4240 name "JSON Mail Access Protocol". This has been de-assigned and
4241 re-assigned with the approval of the previous assignee.
42439.2. Registration of Well-Known URI Suffix for JMAP
4245 IANA has registered the following suffix in the "Well-Known URIs"
4246 registry for JMAP, as described in [RFC8615]:
4250 Change Controller: IETF
4252 Specification Document: RFC 8620, Section 2.2.
4258Jenkins & Newman Standards Track [Page 76]
4260RFC 8620 JMAP July 2019
42639.3. Registration of the jmap URN Sub-namespace
4265 IANA has registered the following URN sub-namespace in the "IETF URN
4266 Sub-namespace for Registered Protocol Parameter Identifiers" registry
4267 within the "Uniform Resource Name (URN) Namespace for IETF Use"
4268 registry as described in [RFC3553].
4270 Registered Parameter Identifier: jmap
4272 Reference: RFC 8620, Section 9.4
4274 IANA Registry Reference: http://www.iana.org/assignments/jmap
42769.4. Creation of "JMAP Capabilities" Registry
4278 IANA has created the "JMAP Capabilities" registry as described in
4279 Section 2. JMAP capabilities are advertised in the "capabilities"
4280 property of the JMAP Session resource. They are used to extend the
4281 functionality of a JMAP server. A capability is referenced by a URI.
4282 The JMAP capability URI can be a URN starting with
4283 "urn:ietf:params:jmap:" plus a unique suffix that is the index value
4284 in the jmap URN sub-namespace. Registration of a JMAP capability
4285 with another form of URI has no impact on the jmap URN sub-namespace.
4287 This registry follows the expert review process unless the "intended
4288 use" field is "common" or "placeholder", in which case registration
4289 follows the specification required process.
4291 A JMAP capability registration can have an intended use of "common",
4292 "placeholder", "limited", or "obsolete". IANA will list common-use
4293 registrations prominently and separately from those with other
4294 intended use values.
4296 The JMAP capability registration procedure is not a formal standards
4297 process but rather an administrative procedure intended to allow
4298 community comment and sanity checking without excessive time delay.
4300 A "placeholder" registration reserves part of the jmap URN namespace
4301 for another purpose but is typically not included in the
4302 "capabilities" property of the JMAP Session resource.
43049.4.1. Preliminary Community Review
4306 Notice of a potential JMAP common-use registration SHOULD be sent to
4307 the JMAP mailing list <jmap@ietf.org> for review. This mailing list
4308 is appropriate to solicit community feedback on a proposed JMAP
4314Jenkins & Newman Standards Track [Page 77]
4316RFC 8620 JMAP July 2019
4319 capability. Registrations that are not intended for common use MAY
4320 be sent to the list for review as well; doing so is entirely
4321 OPTIONAL, but is encouraged.
4323 The intent of the public posting to this list is to solicit comments
4324 and feedback on the choice of the capability name, the unambiguity of
4325 the specification document, and a review of any interoperability or
4326 security considerations. The submitter may submit a revised
4327 registration proposal or abandon the registration completely at any
43309.4.2. Submit Request to IANA
4332 Registration requests can be sent to <iana@iana.org>.
43349.4.3. Designated Expert Review
4336 For a limited-use registration, the primary concern of the designated
4337 expert (DE) is preventing name collisions and encouraging the
4338 submitter to document security and privacy considerations; a
4339 published specification is not required. For a common-use
4340 registration, the DE is expected to confirm that suitable
4341 documentation, as described in Section 4.6 of [RFC8126], is
4342 available. The DE should also verify that the capability does not
4343 conflict with work that is active or already published within the
4346 Before a period of 30 days has passed, the DE will either approve or
4347 deny the registration request and publish a notice of the decision to
4348 the JMAP WG mailing list or its successor, as well as inform IANA. A
4349 denial notice must be justified by an explanation, and, in the cases
4350 where it is possible, concrete suggestions on how the request can be
4351 modified so as to become acceptable should be provided.
4353 If the DE does not respond within 30 days, the registrant may request
4354 the IESG take action to process the request in a timely manner.
43569.4.4. Change Procedures
4358 Once a JMAP capability has been published by the IANA, the change
4359 controller may request a change to its definition. The same
4360 procedure that would be appropriate for the original registration
4361 request is used to process a change request.
4363 JMAP capability registrations may not be deleted; capabilities that
4364 are no longer believed appropriate for use can be declared obsolete
4365 by a change to their "intended use" field; such capabilities will be
4366 clearly marked in the lists published by the IANA.
4370Jenkins & Newman Standards Track [Page 78]
4372RFC 8620 JMAP July 2019
4375 Significant changes to a capability's definition should be requested
4376 only when there are serious omissions or errors in the published
4377 specification. When review is required, a change request may be
4378 denied if it renders entities that were valid under the previous
4379 definition invalid under the new definition.
4381 The owner of a JMAP capability may pass responsibility to another
4382 person or agency by informing the IANA; this can be done without
4383 discussion or review.
4385 The IESG may reassign responsibility for a JMAP capability. The most
4386 common case of this will be to enable changes to be made to
4387 capabilities where the author of the registration has died, moved out
4388 of contact, or is otherwise unable to make changes that are important
43919.4.5. JMAP Capabilities Registry Template
4393 Capability name: (see capability property in Section 2)
4395 Specification document:
4397 Intended use: (one of common, limited, placeholder, or obsolete)
4399 Change controller: ("IETF" for Standards Track / BCP RFCs)
4401 Security and privacy considerations:
44039.4.6. Initial Registration for JMAP Core
4405 Capability Name: "urn:ietf:params:jmap:core"
4407 Specification document: RFC 8620, Section 2
4409 Intended use: common
4411 Change Controller: IETF
4413 Security and privacy considerations: RFC 8620, Section 8.
4426Jenkins & Newman Standards Track [Page 79]
4428RFC 8620 JMAP July 2019
44319.4.7. Registration for JMAP Error Placeholder in JMAP Capabilities
4434 Capability Name: "urn:ietf:params:jmap:error:"
4436 Specification document: RFC 8620, Section 9.5
4438 Intended use: placeholder
4440 Change Controller: IETF
4442 Security and privacy considerations: RFC 8620, Section 8.
44449.5. Creation of "JMAP Error Codes" Registry
4446 IANA has created the "JMAP Error Codes" registry. JMAP error codes
4447 appear in the "type" member of a JSON problem details object (as
4448 described in Section 3.6.1), the "type" member in a JMAP error object
4449 (as described in Section 3.6.2), or the "type" member of a JMAP
4450 method-specific error object (such as SetError in Section 5.3). When
4451 used in a problem details object, the prefix
4452 "urn:ietf:params:jmap:error:" is always included; when used in JMAP
4453 objects, the prefix is always omitted.
4455 This registry follows the expert review process. Preliminary
4456 community review for this registry follows the same procedures as the
4457 "JMAP Capabilities" registry, but it is optional. The change
4458 procedures for this registry are the same as the change procedures
4459 for the "JMAP Capabilities" registry.
4463 The designated expert should review the following aspects of the
4466 1. Verify the error code does not conflict with existing names.
4468 2. Verify the error code follows the syntax limitations (does not
4469 require URI encoding).
4471 3. Encourage the submitter to follow the naming convention of
4472 previously registered errors.
4474 4. Encourage the submitter to describe client behaviours that are
4475 recommended in response to the error code. These may distinguish
4476 the error code from other error codes.
4482Jenkins & Newman Standards Track [Page 80]
4484RFC 8620 JMAP July 2019
4487 5. Encourage the submitter to describe when the server should issue
4488 the error as opposed to some other error code.
4490 6. Encourage the submitter to note any security considerations
4491 associated with the error, if any (e.g., an error code that might
4492 disclose existence of data the authenticated user does not have
4493 permission to know about).
4495 Steps 3-6 are meant to promote a higher-quality registry. However,
4496 the expert is encouraged to approve any registration that would not
4497 actively harm JMAP interoperability to make this a relatively
4498 lightweight process.
45009.5.2. JMAP Error Codes Registry Template
4504 Intended use: (one of "common", "limited", "obsolete")
4506 Change Controller: ("IETF" for Standards Track / BCP RFCs)
4508 Reference: (Optional. Only required if defined in an RFC.)
45129.5.3. Initial Contents for the JMAP Error Codes Registry
4514 o JMAP Error Code: accountNotFound
4515 Intended Use: Common
4516 Change Controller: IETF
4517 Reference: RFC 8620, Section 3.6.2
4518 Description: The accountId does not correspond to a valid account.
4520 o JMAP Error Code: accountNotSupportedByMethod
4521 Intended Use: Common
4522 Change Controller: IETF
4523 Reference: RFC 8620, Section 3.6.2
4524 Description: The accountId given corresponds to a valid account,
4525 but the account does not support this method or data type.
4527 o JMAP Error Code: accountReadOnly
4528 Intended Use: Common
4529 Change Controller: IETF
4530 Reference: RFC 8620, Section 3.6.2
4531 Description: This method modifies state, but the account is read-
4532 only (as returned on the corresponding Account object in the JMAP
4538Jenkins & Newman Standards Track [Page 81]
4540RFC 8620 JMAP July 2019
4543 o JMAP Error Code: anchorNotFound
4544 Intended Use: Common
4545 Change Controller: IETF
4546 Reference: RFC 8620, Section 5.5
4547 Description: An anchor argument was supplied, but it cannot be
4548 found in the results of the query.
4550 o JMAP Error Code: alreadyExists
4551 Intended Use: Common
4552 Change Controller: IETF
4553 Reference: RFC 8620, Section 5.4
4554 Description: The server forbids duplicates, and the record already
4555 exists in the target account. An existingId property of type Id
4556 MUST be included on the SetError object with the id of the
4559 o JMAP Error Code: cannotCalculateChanges
4560 Intended Use: Common
4561 Change Controller: IETF
4562 Reference: RFC 8620, Sections 5.2 and 5.6
4563 Description: The server cannot calculate the changes from the
4564 state string given by the client.
4566 o JMAP Error Code: forbidden
4567 Intended Use: Common
4568 Change Controller: IETF
4569 Reference: RFC 8620, Sections 3.6.2, 5.3, and 7.2.1
4570 Description: The action would violate an ACL or other permissions
4573 o JMAP Error Code: fromAccountNotFound
4574 Intended Use: Common
4575 Change Controller: IETF
4576 Reference: RFC 8620, Sections 5.4 and 6.3
4577 Description: The fromAccountId does not correspond to a valid
4580 o JMAP Error Code: fromAccountNotSupportedByMethod
4581 Intended Use: Common
4582 Change Controller: IETF
4583 Reference: RFC 8620, Section 5.4
4584 Description: The fromAccountId given corresponds to a valid
4585 account, but the account does not support this data type.
4594Jenkins & Newman Standards Track [Page 82]
4596RFC 8620 JMAP July 2019
4599 o JMAP Error Code: invalidArguments
4600 Intended Use: Common
4601 Change Controller: IETF
4602 Reference: RFC 8620, Section 3.6.2
4603 Description: One of the arguments is of the wrong type or
4604 otherwise invalid, or a required argument is missing.
4606 o JMAP Error Code: invalidPatch
4607 Intended Use: Common
4608 Change Controller: IETF
4609 Reference: RFC 8620, Section 5.3
4610 Description: The PatchObject given to update the record was not a
4613 o JMAP Error Code: invalidProperties
4614 Intended Use: Common
4615 Change Controller: IETF
4616 Reference: RFC 8620, Section 5.3
4617 Description: The record given is invalid.
4619 o JMAP Error Code: notFound
4620 Intended Use: Common
4621 Change Controller: IETF
4622 Reference: RFC 8620, Section 5.3
4623 Description: The id given cannot be found.
4625 o JMAP Error Code: notJSON
4626 Intended Use: Common
4627 Change Controller: IETF
4628 Reference: RFC 8620, Section 3.6.1
4629 Description: The content type of the request was not application/
4630 json, or the request did not parse as I-JSON.
4632 o JMAP Error Code: notRequest
4633 Intended Use: Common
4634 Change Controller: IETF
4635 Reference: RFC 8620, Section 3.6.1
4636 Description: The request parsed as JSON but did not match the type
4637 signature of the Request object.
4639 o JMAP Error Code: overQuota
4640 Intended Use: Common
4641 Change Controller: IETF
4642 Reference: RFC 8620, Section 5.3
4643 Description: The create would exceed a server-defined limit on the
4644 number or total size of objects of this type.
4650Jenkins & Newman Standards Track [Page 83]
4652RFC 8620 JMAP July 2019
4655 o JMAP Error Code: rateLimit
4656 Intended Use: Common
4657 Change Controller: IETF
4658 Reference: RFC 8620, Section 5.3
4659 Description: Too many objects of this type have been created
4660 recently, and a server-defined rate limit has been reached. It
4661 may work if tried again later.
4663 o JMAP Error Code: requestTooLarge
4664 Intended Use: Common
4665 Change Controller: IETF
4666 Reference: RFC 8620, Sections 5.1 and 5.3
4667 Description: The total number of actions exceeds the maximum
4668 number the server is willing to process in a single method call.
4670 o JMAP Error Code: invalidResultReference
4671 Intended Use: Common
4672 Change Controller: IETF
4673 Reference: RFC 8620, Section 3.6.2
4674 Description: The method used a result reference for one of its
4675 arguments, but this failed to resolve.
4677 o JMAP Error Code: serverFail
4678 Intended Use: Common
4679 Change Controller: IETF
4680 Reference: RFC 8620, Section 3.6.2
4681 Description: An unexpected or unknown error occurred during the
4682 processing of the call. The method call made no changes to the
4685 o JMAP Error Code: serverPartialFail
4686 Intended Use: Limited
4687 Change Controller: IETF
4688 Reference: RFC 8620, Section 3.6.2
4689 Description: Some, but not all, expected changes described by the
4690 method occurred. The client MUST resynchronise impacted data to
4691 determine the server state. Use of this error is strongly
4694 o JMAP Error Code: serverUnavailable
4695 Intended Use: Common
4696 Change Controller: IETF
4697 Reference: RFC 8620, Section 3.6.2
4698 Description: Some internal server resource was temporarily
4699 unavailable. Attempting the same operation later (perhaps after a
4700 backoff with a random factor) may succeed.
4706Jenkins & Newman Standards Track [Page 84]
4708RFC 8620 JMAP July 2019
4711 o JMAP Error Code: singleton
4712 Intended Use: Common
4713 Change Controller: IETF
4714 Reference: RFC 8620, Section 5.3
4715 Description: This is a singleton type, so you cannot create
4716 another one or destroy the existing one.
4718 o JMAP Error Code: stateMismatch
4719 Intended Use: Common
4720 Change Controller: IETF
4721 Reference: RFC 8620, Section 5.3
4722 Description: An ifInState argument was supplied, and it does not
4723 match the current state.
4725 o JMAP Error Code: tooLarge
4726 Intended Use: Common
4727 Change Controller: IETF
4728 Reference: RFC 8620, Section 5.3
4729 Description: The action would result in an object that exceeds a
4730 server-defined limit for the maximum size of a single object of
4733 o JMAP Error Code: tooManyChanges
4734 Intended Use: Common
4735 Change Controller: IETF
4736 Reference: RFC 8620, Section 5.6
4737 Description: There are more changes than the client's maxChanges
4740 o JMAP Error Code: unknownCapability
4741 Intended Use: Common
4742 Change Controller: IETF
4743 Reference: RFC 8620, Section 3.6.1
4744 Description: The client included a capability in the "using"
4745 property of the request that the server does not support.
4747 o JMAP Error Code: unknownMethod
4748 Intended Use: Common
4749 Change Controller: IETF
4750 Reference: RFC 8620, Section 3.6.2
4751 Description: The server does not recognise this method name.
4753 o JMAP Error Code: unsupportedFilter
4754 Intended Use: Common
4755 Change Controller: IETF
4756 Reference: RFC 8620, Section 5.5
4757 Description: The filter is syntactically valid, but the server
4762Jenkins & Newman Standards Track [Page 85]
4764RFC 8620 JMAP July 2019
4767 o JMAP Error Code: unsupportedSort
4768 Intended Use: Common
4769 Change Controller: IETF
4770 Reference: RFC 8620, Section 5.5
4771 Description: The sort is syntactically valid but includes a
4772 property the server does not support sorting on or a collation
4773 method it does not recognise.
4775 o JMAP Error Code: willDestroy
4776 Intended Use: Common
4777 Change Controller: IETF
4778 Reference: RFC 8620, Section 5.3
4779 Description: The client requested an object be both updated and
4780 destroyed in the same /set request, and the server has decided to
4781 therefore ignore the update.
478510.1. Normative References
4788 Hickson, I., "Server-Sent Events", World Wide Web
4789 Consortium Recommendation REC-eventsource-20150203,
4790 February 2015, <https://www.w3.org/TR/eventsource/>.
4792 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
4793 Requirement Levels", BCP 14, RFC 2119,
4794 DOI 10.17487/RFC2119, March 1997,
4795 <https://www.rfc-editor.org/info/rfc2119>.
4797 [RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
4798 specifying the location of services (DNS SRV)", RFC 2782,
4799 DOI 10.17487/RFC2782, February 2000,
4800 <https://www.rfc-editor.org/info/rfc2782>.
4802 [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
4803 DOI 10.17487/RFC2818, May 2000,
4804 <https://www.rfc-editor.org/info/rfc2818>.
4806 [RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
4807 Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
4808 <https://www.rfc-editor.org/info/rfc3339>.
4810 [RFC3553] Mealling, M., Masinter, L., Hardie, T., and G. Klyne, "An
4811 IETF URN Sub-namespace for Registered Protocol
4812 Parameters", BCP 73, RFC 3553, DOI 10.17487/RFC3553, June
4813 2003, <https://www.rfc-editor.org/info/rfc3553>.
4818Jenkins & Newman Standards Track [Page 86]
4820RFC 8620 JMAP July 2019
4823 [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
4824 10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
4825 2003, <https://www.rfc-editor.org/info/rfc3629>.
4827 [RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
4828 Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
4829 <https://www.rfc-editor.org/info/rfc4648>.
4831 [RFC4790] Newman, C., Duerst, M., and A. Gulbrandsen, "Internet
4832 Application Protocol Collation Registry", RFC 4790,
4833 DOI 10.17487/RFC4790, March 2007,
4834 <https://www.rfc-editor.org/info/rfc4790>.
4836 [RFC5051] Crispin, M., "i;unicode-casemap - Simple Unicode Collation
4837 Algorithm", RFC 5051, DOI 10.17487/RFC5051, October 2007,
4838 <https://www.rfc-editor.org/info/rfc5051>.
4840 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
4841 (TLS) Protocol Version 1.2", RFC 5246,
4842 DOI 10.17487/RFC5246, August 2008,
4843 <https://www.rfc-editor.org/info/rfc5246>.
4845 [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
4846 Housley, R., and W. Polk, "Internet X.509 Public Key
4847 Infrastructure Certificate and Certificate Revocation List
4848 (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
4849 <https://www.rfc-editor.org/info/rfc5280>.
4851 [RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
4852 DOI 10.17487/RFC5322, October 2008,
4853 <https://www.rfc-editor.org/info/rfc5322>.
4855 [RFC6186] Daboo, C., "Use of SRV Records for Locating Email
4856 Submission/Access Services", RFC 6186,
4857 DOI 10.17487/RFC6186, March 2011,
4858 <https://www.rfc-editor.org/info/rfc6186>.
4860 [RFC6335] Cotton, M., Eggert, L., Touch, J., Westerlund, M., and S.
4861 Cheshire, "Internet Assigned Numbers Authority (IANA)
4862 Procedures for the Management of the Service Name and
4863 Transport Protocol Port Number Registry", BCP 165,
4864 RFC 6335, DOI 10.17487/RFC6335, August 2011,
4865 <https://www.rfc-editor.org/info/rfc6335>.
4867 [RFC6570] Gregorio, J., Fielding, R., Hadley, M., Nottingham, M.,
4868 and D. Orchard, "URI Template", RFC 6570,
4869 DOI 10.17487/RFC6570, March 2012,
4870 <https://www.rfc-editor.org/info/rfc6570>.
4874Jenkins & Newman Standards Track [Page 87]
4876RFC 8620 JMAP July 2019
4879 [RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
4880 RFC 6749, DOI 10.17487/RFC6749, October 2012,
4881 <https://www.rfc-editor.org/info/rfc6749>.
4883 [RFC6764] Daboo, C., "Locating Services for Calendaring Extensions
4884 to WebDAV (CalDAV) and vCard Extensions to WebDAV
4885 (CardDAV)", RFC 6764, DOI 10.17487/RFC6764, February 2013,
4886 <https://www.rfc-editor.org/info/rfc6764>.
4888 [RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
4889 Specifications and Registration Procedures", BCP 13,
4890 RFC 6838, DOI 10.17487/RFC6838, January 2013,
4891 <https://www.rfc-editor.org/info/rfc6838>.
4893 [RFC6901] Bryan, P., Ed., Zyp, K., and M. Nottingham, Ed.,
4894 "JavaScript Object Notation (JSON) Pointer", RFC 6901,
4895 DOI 10.17487/RFC6901, April 2013,
4896 <https://www.rfc-editor.org/info/rfc6901>.
4898 [RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
4899 Protocol (HTTP/1.1): Message Syntax and Routing",
4900 RFC 7230, DOI 10.17487/RFC7230, June 2014,
4901 <https://www.rfc-editor.org/info/rfc7230>.
4903 [RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
4904 Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
4905 DOI 10.17487/RFC7231, June 2014,
4906 <https://www.rfc-editor.org/info/rfc7231>.
4908 [RFC7493] Bray, T., Ed., "The I-JSON Message Format", RFC 7493,
4909 DOI 10.17487/RFC7493, March 2015,
4910 <https://www.rfc-editor.org/info/rfc7493>.
4912 [RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
4913 "Recommendations for Secure Use of Transport Layer
4914 Security (TLS) and Datagram Transport Layer Security
4915 (DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
4916 2015, <https://www.rfc-editor.org/info/rfc7525>.
4918 [RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
4919 RFC 7617, DOI 10.17487/RFC7617, September 2015,
4920 <https://www.rfc-editor.org/info/rfc7617>.
4922 [RFC7807] Nottingham, M. and E. Wilde, "Problem Details for HTTP
4923 APIs", RFC 7807, DOI 10.17487/RFC7807, March 2016,
4924 <https://www.rfc-editor.org/info/rfc7807>.
4930Jenkins & Newman Standards Track [Page 88]
4932RFC 8620 JMAP July 2019
4935 [RFC8030] Thomson, M., Damaggio, E., and B. Raymor, Ed., "Generic
4936 Event Delivery Using HTTP Push", RFC 8030,
4937 DOI 10.17487/RFC8030, December 2016,
4938 <https://www.rfc-editor.org/info/rfc8030>.
4940 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
4941 Writing an IANA Considerations Section in RFCs", BCP 26,
4942 RFC 8126, DOI 10.17487/RFC8126, June 2017,
4943 <https://www.rfc-editor.org/info/rfc8126>.
4945 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
4946 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
4947 May 2017, <https://www.rfc-editor.org/info/rfc8174>.
4949 [RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
4950 Interchange Format", STD 90, RFC 8259,
4951 DOI 10.17487/RFC8259, December 2017,
4952 <https://www.rfc-editor.org/info/rfc8259>.
4954 [RFC8264] Saint-Andre, P. and M. Blanchet, "PRECIS Framework:
4955 Preparation, Enforcement, and Comparison of
4956 Internationalized Strings in Application Protocols",
4957 RFC 8264, DOI 10.17487/RFC8264, October 2017,
4958 <https://www.rfc-editor.org/info/rfc8264>.
4960 [RFC8291] Thomson, M., "Message Encryption for Web Push", RFC 8291,
4961 DOI 10.17487/RFC8291, November 2017,
4962 <https://www.rfc-editor.org/info/rfc8291>.
4964 [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
4965 Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
4966 <https://www.rfc-editor.org/info/rfc8446>.
4968 [RFC8615] Nottingham, M., "Well-Known Uniform Resource Identifiers
4969 (URIs)", RFC 8615, DOI 10.17487/RFC8615, May 2019,
4970 <https://www.rfc-editor.org/info/rfc8615>.
497210.2. Informative References
4974 [RFC8246] McManus, P., "HTTP Immutable Responses", RFC 8246,
4975 DOI 10.17487/RFC8246, September 2017,
4976 <https://www.rfc-editor.org/info/rfc8246>.
4986Jenkins & Newman Standards Track [Page 89]
4988RFC 8620 JMAP July 2019
4995 PO Box 234, Collins St. West
4999 Email: neilj@fastmailteam.com
5000 URI: https://www.fastmail.com
5005 440 E. Huntington Dr., Suite 400
5007 United States of America
5009 Email: chris.newman@oracle.com
5042Jenkins & Newman Standards Track [Page 90]