Internet DRAFT - draft-ietf-jmap-contacts

draft-ietf-jmap-contacts







JMAP                                                   N.M. Jenkins, Ed.
Internet-Draft                                                  Fastmail
Intended status: Standards Track                        20 February 2024
Expires: 23 August 2024


                           JMAP for Contacts
                      draft-ietf-jmap-contacts-04

Abstract

   This document specifies a data model for synchronising contacts data
   with a server using JMAP.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 23 August 2024.

Copyright Notice

   Copyright (c) 2024 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
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   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2



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     1.1.  Notational conventions  . . . . . . . . . . . . . . . . .   3
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     1.3.  Data Model Overview . . . . . . . . . . . . . . . . . . .   3
     1.4.  Addition to the Capabilities Object . . . . . . . . . . .   3
       1.4.1.  urn:ietf:params:jmap:contacts . . . . . . . . . . . .   3
   2.  AddressBooks  . . . . . . . . . . . . . . . . . . . . . . . .   4
     2.1.  AddressBook/get . . . . . . . . . . . . . . . . . . . . .   6
     2.2.  AddressBook/changes . . . . . . . . . . . . . . . . . . .   6
     2.3.  AddressBook/set . . . . . . . . . . . . . . . . . . . . .   6
   3.  ContactCards  . . . . . . . . . . . . . . . . . . . . . . . .   7
     3.1.  ContactCard/get . . . . . . . . . . . . . . . . . . . . .   8
     3.2.  ContactCard/changes . . . . . . . . . . . . . . . . . . .   8
     3.3.  ContactCard/query . . . . . . . . . . . . . . . . . . . .   8
       3.3.1.  Filtering . . . . . . . . . . . . . . . . . . . . . .   8
       3.3.2.  Sorting . . . . . . . . . . . . . . . . . . . . . . .  10
     3.4.  ContactCard/queryChanges  . . . . . . . . . . . . . . . .  11
     3.5.  ContactCard/set . . . . . . . . . . . . . . . . . . . . .  11
     3.6.  ContactCard/copy  . . . . . . . . . . . . . . . . . . . .  11
   4.  Examples  . . . . . . . . . . . . . . . . . . . . . . . . . .  11
     4.1.  Fetching initial data . . . . . . . . . . . . . . . . . .  11
     4.2.  Changing the default address book . . . . . . . . . . . .  13
   5.  Security considerations . . . . . . . . . . . . . . . . . . .  14
     5.1.  Privacy . . . . . . . . . . . . . . . . . . . . . . . . .  14
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
     6.1.  JMAP capability registration for "contacts" . . . . . . .  14
     6.2.  JSContact Property Registrations  . . . . . . . . . . . .  14
       6.2.1.  id  . . . . . . . . . . . . . . . . . . . . . . . . .  14
       6.2.2.  addressBookIds  . . . . . . . . . . . . . . . . . . .  15
       6.2.3.  blobId  . . . . . . . . . . . . . . . . . . . . . . .  15
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .  15
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   JMAP ([RFC8620] JSON Meta Application Protocol) is a generic protocol
   for synchronising data, such as mail, calendars or contacts, between
   a client and a server.  It is optimised for mobile and web
   environments, and aims to provide a consistent interface to different
   data types.

   This specification defines a data model for synchronising contacts
   between a client and a server using JMAP.









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1.1.  Notational conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   Type signatures, examples and property descriptions in this document
   follow the conventions established in Section 1.1 of [RFC8620].  The
   Id and UnsignedInt data types defined in Sections 1.2 and 1.3 of
   [RFC8620] are also used in this document.

1.2.  Terminology

   The same terminology is used in this document as in the core JMAP
   specification, see [RFC8620], Section 1.6.

   The terms AddressBook and ContactCard (with these specific
   capitalizations) are used to refer to the data types defined in this
   document and instances of those data types.

1.3.  Data Model Overview

   An Account (see [RFC8620], Section 1.6.2) with support for the
   contacts data model contains zero or more AddressBook objects, which
   is a named collection of zero or more ContactCards.  A ContactCard is
   a representation of a person, company, or other entity, or a group of
   such entities, in JSContact Card format, as defined in Section 2 of
   [I-D.ietf-calext-jscontact].  Each ContactCard belongs to one or more
   AddressBooks.

   In servers with support for JMAP Sharing [I-D.ietf-jmap-sharing],
   data may be shared with other users.  Sharing permissions are managed
   per AddressBook.

1.4.  Addition to the Capabilities Object

   The capabilities object is returned as part of the JMAP Session
   object; see [RFC8620], Section 2.  This document defines two
   additional capability URIs.

1.4.1.  urn:ietf:params:jmap:contacts

   This represents support for the AddressBook and ContactCard data
   types and associated API methods.  The value of this property in the
   JMAP Session capabilities property is an empty object.




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   The value of this property in an account's accountCapabilities
   property is an object that MUST contain the following information on
   server capabilities and permissions for that account:

   *  *maxAddressBooksPerCard*: UnsignedInt|null
      The maximum number of AddressBooks (see Section 2) that can be can
      assigned to a single ContactCard object (see Section 3).  This
      MUST be an integer >= 1, or null for no limit (or rather, the
      limit is always the number of AddressBooks in the account).
   *  *mayCreateAddressBook*: Boolean
      If true, the user may create an AddressBook in this account.

2.  AddressBooks

   An AddressBook is a named collection of ContactCards.  All
   ContactCards are associated with one or more AddressBook.

   A *AddressBook* object has the following properties:

   *  *id*: Id (immutable; server-set)

      The id of the AddressBook.

   *  *name*: String

      The user-visible name of the AddressBook.  This may be any UTF-8
      string of at least 1 character in length and maximum 255 octets in
      size.

   *  *description*: String|null (default: null)

      An optional longer-form description of the AddressBook, to provide
      context in shared environments where users need more than just the
      name.

   *  *sortOrder*: UnsignedInt (default: 0)

      Defines the sort order of AddressBooks when presented in the
      client's UI, so it is consistent between devices.  The number MUST
      be an integer in the range 0 <= sortOrder < 2^(31.)

      An AddressBook with a lower order should be displayed before a
      AddressBook with a higher order in any list of AddressBooks in the
      client's UI.  AddressBooks with equal order SHOULD be sorted in
      alphabetical order by name.  The sorting should take into account
      locale-specific character order convention.

   *  *isDefault*: Boolean (server-set)



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      This SHOULD be true for exactly one AddressBook in any account,
      and MUST NOT be true for more than one AddressBook within an
      account.  The default AddressBook should be used by clients
      whenever they need to choose an AddressBook for the user within
      this account, and they do not have any other information on which
      to make a choice.  For example, if the user creates a new contact
      card, the client may automatically set the card as belonging to
      the default AddressBook from the user's primary account.

   *  *isSubscribed*: Boolean

      True if the user has indicated they wish to see this AddressBook
      in their client.  This SHOULD default to false for AddressBooks in
      shared accounts the user has access to and true for any new
      AddressBooks created by the user themself.

      If false, the AddressBook and its contents SHOULD only be
      displayed when the user explicitly requests it or to offer it for
      the user to subscribe to.

   *  *shareWith*: Id[AddressBookRights]|null (default: null)

      A map of Principal id to rights for principals this AddressBook is
      shared with.  The principal to which this AddressBook belongs MUST
      NOT be in this set.  This is null if the AddressBook is not shared
      with anyone.  May be modified only if the user has the mayAdmin
      right.  The account id for the principals may be found in the
      urn:ietf:params:jmap:principals:owner capability of the Account to
      which the AddressBook belongs.

   *  *myRights*: AddressBookRights (server-set)

      The set of access rights the user has in relation to this
      AddressBook.

   An *AddressBookRights* object has the following properties:

   *  *mayRead*: Boolean
      The user may fetch the ContactCards in this AddressBook.
   *  *mayWrite*: Boolean
      The user may create, modify or destroy all ContactCards in this
      AddressBook, or move them to or from this AddressBook.
   *  *mayAdmin*: Boolean
      The user may modify the "shareWith" property for this AddressBook.
   *  *mayDelete*: Boolean
      The user may delete the AddressBook itself.





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2.1.  AddressBook/get

   This is a standard "/get" method as described in [RFC8620],
   Section 5.1.  The _ids_ argument may be null to fetch all at once.

2.2.  AddressBook/changes

   This is a standard "/changes" method as described in [RFC8620],
   Section 5.2.

2.3.  AddressBook/set

   This is a standard "/set" method as described in [RFC8620],
   Section 5.3 but with the following additional request argument:

   *  *onDestroyRemoveContents*: Boolean (default: false)

      If false, any attempt to destroy an AddressBook that still has
      ContactCard in it will be rejected with an addressBookHasContents
      SetError.  If true, any ContactCards that were in the AddressBook
      will be removed from it, and if in no other AddressBooks they will
      be destroyed.

   *  *onSuccessSetIsDefault*: Id|null

      If an id is given, and all creates, updates and destroys (if any)
      succeed without error, the server will try to set this AddressBook
      as the default.  (For references to AddressBook creations, this is
      equivalent to a creation-reference, so the id will be the creation
      id prefixed with a "#".)

   If the id is not found, or the change is not permitted by the server
   for policy reasons, it MUST be ignored and the currently default
   AddressBook (if any) will remain as such.  No error is returned to
   the client in this case.

   As per [RFC8620], Section 5.3, if the default is successfully
   changed, any changed objects MUST be reported in either the "created"
   or "updated" argument in the response as appropriate, with the
   server-set value included.

   The "shareWith" property may only be set by users that have the
   mayAdmin right.  When modifying the shareWith property, the user
   cannot give a right to a principal if the principal did not already
   have that right and the user making the change also does not have
   that right.  Any attempt to do so must be rejected with a forbidden
   SetError.




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   Users can subscribe or unsubscribe to an AddressBook by setting the
   "isSubscribed" property.  The server MAY forbid users from
   subscribing to certain AddressBooks even though they have permission
   to see them, rejecting the update with a forbidden SetError.

   The following extra SetError types are defined:

   For "destroy":

   *  *addressBookHasContents*: The AddressBook has at least one
      ContactCard assigned to it, and the "onDestroyRemoveContents"
      argument was false.

3.  ContactCards

   A *ContactCard* object contains information about a person, company,
   or other entity, or represents a group of such entities.  It is a
   JSContact Card object, as defined in Section 2 of
   [I-D.ietf-calext-jscontact], with the following additional
   properties:

   *  *id*: Id (immutable; server-set)
      The id of the ContactCard.  The id uniquely identifies a
      ContactCard with a particular "uid" within a particular account.
   *  *addressBookIds*: Id[Boolean]
      The set of AddressBook ids this ContactCard belongs to.  A card
      MUST belong to at least one AddressBook at all times (until it is
      destroyed).  The set is represented as an object, with each key
      being an AddressBook id.  The value for each key in the object
      MUST be true.

   For any Media object in the card (see Section 2.6.4 of
   [I-D.ietf-calext-jscontact]), a new property is defined:

   *  *blobId*: Id
      An id for the Blob representing the binary contents of the
      resource.

   When returning ContactCards, any Media with a data: URI SHOULD return
   a blobId property and omit the uri property.  The "mediaType"
   property MUST also be set.  Similarly, when creating or updating a
   ContactCard, clients MAY send a blobId instead of the uri property
   for a Media object.

   A contact card with a "kind" property equal to "group" represents a
   group of contacts.  Clients often present these separately from other
   contact cards.  The "members" property, as defined in Section 2.1.6
   of [I-D.ietf-calext-jscontact], contains a set of UIDs for other



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   contacts that are the members of this group.  Clients should consider
   the group to contain any ContactCard with a matching UID, from any
   account they have access to with support for the
   urn:ietf:params:jmap:contacts capability.  UIDs that cannot be found
   SHOULD be ignored but preserved.  For example, suppose a user adds
   contacts from a shared address book to their private group, then
   temporarily loses access to this address book.  The UIDs cannot be
   resolved so the contacts will disappear from the group.  However, if
   they are given permission to access the data again the UIDs will be
   found and the contacts will reappear.

3.1.  ContactCard/get

   This is a standard "/get" method as described in [RFC8620],
   Section 5.1.

3.2.  ContactCard/changes

   This is a standard "/changes" method as described in [RFC8620],
   Section 5.2.

3.3.  ContactCard/query

   This is a standard "/query" method as described in [RFC8620],
   Section 5.5.

3.3.1.  Filtering

   A *FilterCondition* object has the following properties, any of which
   may be omitted:

   *  *inAddressBook*: Id
      An AddressBook id.  A card must be in this address book to match
      the condition.
   *  *uid*: String
      A card must have this string exactly as its uid to match.
   *  *hasMember*: String
      A card must have a "members" property that contains this string as
      one of the uids in the set to match.
   *  *kind*: String
      A card must have a type property that equals this string exactly
      to match.
   *  *createdBefore*: UTCDate
      The "created" date-time of the ContactCard must be before this
      date-time to match the condition.
   *  *createdAfter*: UTCDate
      The "created" date-time of the ContactCard must be the same or
      after this date-time to match the condition.



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   *  *updatedBefore*: UTCDate
      The "updated" date-time of the ContactCard must be before this
      date-time to match the condition.
   *  *updatedAfter*: UTCDate
      The "updated" date-time of the ContactCard must be the same or
      after this date-time to match the condition.
   *  *text*: String
      A card matches this condition if the text matches with text in the
      card.
   *  *name*: String
      A card matches this condition if the value of any NameComponent in
      the "name" property, or the "full" property in the "name" property
      of the card matches the value.
   *  *name/given*: String
      A card matches this condition if the value of a NameComponent with
      kind "given" inside the "name" property of the card matches the
      value.
   *  *name/surname*: String
      A card matches this condition if the value of a NameComponent with
      kind "surname" inside the "name" property of the card matches the
      value.
   *  *name/surname2*: String
      A card matches this condition if the value of a NameComponent with
      kind "surname2" inside the "name" property of the card matches the
      value.
   *  *nickName*: String
      A card matches this condition if the "name" of any NickName in the
      "nickNames" property of the card matches the value.
   *  *organization*: String
      A card matches this condition if the "name" of any Organization in
      the "organizations" property of the card matches the value.
   *  *email*: String
      A card matches this condition if the "address" or "label" of any
      EmailAddress in the "emails" property of the card matches the
      value.
   *  *phone*: String
      A card matches this condition if the "number" or "label" of any
      Phone in the "phones" property of the card matches the value.
   *  *onlineService*: String
      A card matches this condition if the "service", "uri", "user", or
      "label" of any OnlineService in the "onlineServices" property of
      the card matches the value.
   *  *address*: String
      A card matches this condition if the value of any StreetComponent
      in the "street" property, or the "locality", "region", "country",
      or "postcode" property in any Address in the "addresses" property
      of the card matches the value.
   *  *note*: String



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      A card matches this condition if the "note" of any Note in the
      "notes" property of the card matches the value.

   If zero properties are specified on the FilterCondition, the
   condition MUST always evaluate to true.  If multiple properties are
   specified, ALL must apply for the condition to be true (it is
   equivalent to splitting the object into one-property conditions and
   making them all the child of an AND filter operator).

   The exact semantics for matching String fields is *deliberately not
   defined* to allow for flexibility in indexing implementation, subject
   to the following:

   *  Text SHOULD be matched in a case-insensitive manner.
   *  Text contained in either (but matched) single or double quotes
      SHOULD be treated as a *phrase search*, that is a match is
      required for that exact sequence of words, excluding the
      surrounding quotation marks.  Use \", \' and \\ to match a literal
      ", ' and \ respectively in a phrase.
   *  Outside of a phrase, white-space SHOULD be treated as dividing
      separate tokens that may be searched for separately in the
      contact, but MUST all be present for the contact to match the
      filter.
   *  Tokens MAY be matched on a whole-word basis using stemming (so for
      example a text search for bus would match "buses" but not
      "business").

3.3.2.  Sorting

   The following value for the "property" field on the Comparator object
   MUST be supported for sorting:

   *  "created" - The "created" date on the ContactCard.
   *  "updated" - The "updated" date on the ContactCard.

   The following values for the "property" field on the Comparator
   object SHOULD be supported for sorting:

   *  "name/given" - The value of the first NameComponent in the "name"
      property whose "kind" is "given".
   *  "name/surname" - The value of the first NameComponent in the
      "name" property whose "kind" is "surname".
   *  "name/surname2" - The value of the first NameComponent in the
      "name" property whose "kind" is "surname2".







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3.4.  ContactCard/queryChanges

   This is a standard "/queryChanges" method as described in [RFC8620],
   Section 5.6.

3.5.  ContactCard/set

   This is a standard "/set" method as described in [RFC8620],
   Section 5.3.

   To set a new photo, the file must first be uploaded using the upload
   mechanism as described in [RFC8620], Section 6.1.  This will give the
   client a valid blobId/size/type to use.  The server SHOULD reject
   attempts to set a file that is not a recognised image type as the
   photo for a card.

3.6.  ContactCard/copy

   This is a standard "/copy" method as described in [RFC8620],
   Section 5.4.

4.  Examples

   For brevity, in the following examples only the "methodCalls"
   property of the Request object, and the "methodResponses" property of
   the Response object is shown.

4.1.  Fetching initial data

   A user has authenticated and the client has fetched the JMAP Session
   object.  It finds a single Account with the
   "urn:ietf:params:jmap:contacts" capability, with id "a0x9", and wants
   to fetch all the address books and contacts.  It might make the
   following request:

   [
     ["AddressBook/get", {
       "accountId": "a0x9"
     }, "0"],
     ["ContactCard/get", {
       "accountId": "a0x9"
     }, "1"]
   ]

   The server might respond with something like:






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   [
     ["AddressBook/get", {
       "accountId": "a0x9",
       "list": [{
           "id": "062adcfa-105d-455c-bc60-6db68b69c3f3",
           "name": "Personal",
           "description": null,
           "sortOrder": 0,
           "isDefault": true,
           "isSubscribed": true,
           "shareWith": null,
           "myRights": {
             "mayRead": true,
             "mayWrite": true,
             "mayAdmin": true,
             "mayDelete": false
           }
         }, {
           "id": "cd40089d-35f9-4fd7-980b-ba3a9f1d74fe",
           "name": "Autosaved",
           "description": null,
           "sortOrder": 1,
           "isDefault": false,
           "isSubscribed": true,
           "shareWith": null,
           "myRights": {
             "mayRead": true,
             "mayWrite": true,
             "mayAdmin": true,
             "mayDelete": false
           }
         }],
         "notFound": [],
         "state": "~4144"
     }, "0"],
     ["Contact/get", {
       "accountId": "a0x9",
       "list": [{
           "id": "3",
           "addressBookIds": {
             "062adcfa-105d-455c-bc60-6db68b69c3f3": true
           },
           "name": {
             "components": [
               { "kind": "given", "value": "Joe" },
               { "kind": "surname", "value": "Bloggs" }
             ],
             "isOrdered": true



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           },
           "emails": {
             "0": {
             "contexts": {
               "private": true
             },
             "address": "joe.bloggs@example.com"
             }
           }
         }],
         "notFound": [],
         "state": "ewarbckaqJ::112"
     }, "1"]
   ]

4.2.  Changing the default address book

   The client tries to change the default address book from "Personal"
   to "Autosaved" (and makes no other change):

   [
     ["AddressBook/set", {
       "accountId": "a0x9",
       "onSuccessSetIsDefault": "cd40089d-35f9-4fd7-980b-ba3a9f1d74fe"
     }, "0"]
   ]

   The server allows the change, returning the following response:

   [
     ["AddressBook/set", {
       "accountId": "a0x9",
       "updated": {
         "cd40089d-35f9-4fd7-980b-ba3a9f1d74fe": {
           "isDefault": true
         },
         "062adcfa-105d-455c-bc60-6db68b69c3f3": {
           "isDefault": false
         }
       }
     }, "0"]
   ]









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5.  Security considerations

   All security considerations of JMAP ([RFC8620]) apply to this
   specification.  Additional considerations specific to the data types
   and functionality introduced by this document are described in the
   following subsection.

5.1.  Privacy

   Contacts consist almost entirely of private, personally identifiable
   information, and represent the social connections of users.  Privacy
   leaks can have real world consequences, and contacts servers and
   clients MUST be mindful of the need to keep all data secure.

   Servers MUST enforce the ACLs set on address books to ensure only
   authorised data is shared.

6.  IANA Considerations

6.1.  JMAP capability registration for "contacts"

   IANA will register the "contacts" JMAP Capability as follows:

   Capability Name: urn:ietf:params:jmap:contacts

   Specification document: this document

   Intended use: common

   Change Controller: IETF

   Security and privacy considerations: this document, Section 5

6.2.  JSContact Property Registrations

   IANA will register the following additional properties in the
   JSContact Properties Registry.

6.2.1.  id

   Property Name: id

   Property Type: Id

   Property Context: Card

   Intended Use: Reserved




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   Since Version: 1.0

   Change Controller: IETF

6.2.2.  addressBookIds

   Property Name: addressBookIds

   Property Type: Id

   Property Context: Card

   Intended Use: Reserved

   Since Version: 1.0

   Change Controller: IETF

6.2.3.  blobId

   Property Name: blobId

   Property Type: Id

   Property Context: Media

   Intended Use: Reserved

   Since Version: 1.0

   Change Controller: IETF

7.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8620]  Jenkins, N. and C. Newman, "The JSON Meta Application
              Protocol (JMAP)", RFC 8620, DOI 10.17487/RFC8620, July
              2019, <https://www.rfc-editor.org/info/rfc8620>.





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   [I-D.ietf-jmap-sharing]
              Jenkins, N., "JMAP Sharing", Work in Progress, Internet-
              Draft, draft-ietf-jmap-sharing-05, 5 February 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-jmap-
              sharing-05>.

   [I-D.ietf-calext-jscontact]
              Stepanek, R. and M. Loffredo, "JSContact: A JSON
              representation of contact data", Work in Progress,
              Internet-Draft, draft-ietf-calext-jscontact-16, 8 November
              2023, <https://datatracker.ietf.org/doc/html/draft-ietf-
              calext-jscontact-16>.

Author's Address

   Neil Jenkins (editor)
   Fastmail
   PO Box 234, Collins St West
   Melbourne  VIC 8007
   Australia
   Email: neilj@fastmailteam.com
   URI:   https://www.fastmail.com





























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