JMAP                                                        K. Murchison
Internet-Draft                                                  Fastmail
Intended status: Standards Track                       December 17, 2020
Expires: June 20, 2021


                         JMAP for Sieve Scripts
                        draft-ietf-jmap-sieve-03

Abstract

   This document specifies a data model for managing Sieve scripts on a
   server using the JSON Meta Application Protocol (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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on June 20, 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.






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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Notational Conventions  . . . . . . . . . . . . . . . . .   3
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     1.3.  Addition to the Capabilities Object . . . . . . . . . . .   3
       1.3.1.  urn:ietf:params:jmap:sieve  . . . . . . . . . . . . .   3
   2.  Sieve Scripts . . . . . . . . . . . . . . . . . . . . . . . .   5
     2.1.  SieveScript/get . . . . . . . . . . . . . . . . . . . . .   6
     2.2.  SieveScript/set . . . . . . . . . . . . . . . . . . . . .   6
       2.2.1.  Examples  . . . . . . . . . . . . . . . . . . . . . .   8
     2.3.  SieveScript/query . . . . . . . . . . . . . . . . . . . .  15
     2.4.  SieveScript/validate  . . . . . . . . . . . . . . . . . .  15
     2.5.  SieveScript/test  . . . . . . . . . . . . . . . . . . . .  16
       2.5.1.  Example . . . . . . . . . . . . . . . . . . . . . . .  19
   3.  Compatibility with JMAP Vacation Response . . . . . . . . . .  22
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  22
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  22
     5.1.  JMAP Capability Registration for "sieve"  . . . . . . . .  22
     5.2.  JMAP Error Codes Registry . . . . . . . . . . . . . . . .  22
       5.2.1.  invalidScript . . . . . . . . . . . . . . . . . . . .  23
       5.2.2.  scriptIsActive  . . . . . . . . . . . . . . . . . . .  23
   6.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  23
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  23
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  23
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  24
   Appendix A.  Change History (To be removed by RFC Editor before
                publication) . . . . . . . . . . . . . . . . . . . .  25
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  26

1.  Introduction

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

   This specification defines a data model for managing Sieve [RFC5228]
   scripts on a server using JMAP.  The data model is designed to allow
   a server to provide consistent access to the same scripts via
   ManageSieve [RFC5804] as well as JMAP, however the functionality
   offered over the two protocols may differ.








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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].  Data
   types defined in the core specification are also used in this
   document.

   Servers MUST support all properties specified for the new data type
   defined in this document.

   For compatibility with publishing requirements, line breaks have been
   inserted inside long JSON strings, with the following continuation
   lines indented.  To form the valid JSON example, any line breaks
   inside a string must be replaced with a space and any other white
   space after the line break removed.

1.2.  Terminology

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

   The term SieveScript (with this specific capitalization) is used to
   refer to the data type defined in this document and instances of
   those data types.

1.3.  Addition to the Capabilities Object

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

1.3.1.  urn:ietf:params:jmap:sieve

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

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

   o  *supportsTest*: "Boolean"



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      If true, the server supports the SieveScript/test (Section 2.5)
      method.



   o  *maxSizeScriptName*: "UnsignedInt"

      The maximum length, in (UTF-8) octets, allowed for the name of a
      SieveScript.  For compatibility with ManageSieve, this MUST be at
      least 512 (up to 128 Unicode characters).



   o  *maxSizeScript*: "UnsignedInt|null"

      The maximum size (in octets) of a Sieve script the server is
      willing to store for the user, or "null" for no limit.



   o  *maxNumberScripts*: "UnsignedInt|null"

      The maximum number of Sieve scripts the server is willing to store
      for the user, or "null" for no limit.



   o  *maxNumberRedirects*: "UnsignedInt|null"

      The maximum number of Sieve "redirect" actions a script can
      perform during a single evaluation or "null" for no limit.  Note
      that this is different from the total number of "redirect" actions
      a script can contain.



   o  *sieveExtensions*: "String[]"

      A list of case-sensitive Sieve capability strings (as listed in
      Sieve "require" action; see [RFC5228], Section 3.2) indicating the
      extensions supported by the Sieve engine.



   o  *notificationMethods*: "String[]|null"






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      A list of URI schema parts [RFC3986] for notification methods
      supported by the Sieve "enotify" [RFC5435] extension, or "null" if
      the extension is not supported by the Sieve engine.



   o  *externalLists*: "String[]|null"

      A list of URI schema parts [RFC3986] for externally stored list
      types supported by the Sieve "extlists" [RFC6134] extension, or
      "null" if the extension is not supported by the Sieve engine.

2.  Sieve Scripts

   A *SieveScript* object represents a single Sieve [RFC5228] script for
   filtering email messages at time of final delivery.

   A *SieveScript* object has the following properties:

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

      The id of the script.



   o  *name*: "String|null" (optional; default is server-dependent)

      User-visible name for the SieveScript.  If non-null, this MUST be
      a Net-Unicode [RFC5198] string of at least 1 character in length,
      subject to the maximum size given in the capability object.  For
      compatibility with ManageSieve, servers MUST reject names that
      contain control characters.  Servers MAY reject names that violate
      server policy (e.g., names containing slash (/)).  The name MUST
      be unique among all SieveScripts within an account.



   o  *blobId*: "Id"

      The id of the blob containing the raw octets of the script.

      The script MUST be UTF-8 [RFC3629] content of at least 1 character
      in length, subject to the syntax of Sieve [RFC5228].  The script
      MUST NOT contain any "require" statement(s) mentioning Sieve
      capabiltity strings not present in the capability (Section 1.3.1)
      object.  Note that if the Sieve "ihave" [RFC5463] capability
      string is present in the capability object, the script MAY mention
      unrecognized/unsupported extensions in the "ihave" test.



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   o  *isActive*: "Boolean" (server-set; default: false)

      A user may have multiple SieveScripts on the server, yet only one
      script may be used for filtering of incoming messages.  This is
      the active script.  Users may have zero or one active script.  The
      SieveScript/set (Section 2.2) method is used for changing the
      active script or disabling Sieve processing.



2.1.  SieveScript/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.

   This method provides similar functionality to the GETSCRIPT and
   LISTSCRIPTS commands in [RFC5804].

2.2.  SieveScript/set

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

   o  *onSuccessActivateScript*: "Id|null" (optional)

      If "null", the currently active SieveScript (if any) will be
      deactivated if and only if all of the creations, modifications,
      and destructions (if any) succeed.  Otherwise, the id of the
      SieveScript to activate if and only if all of the creations,
      modifications, and destructions (if any) succeed.  (For references
      to SieveScript creations, this is equivalent to a creation-
      reference, so the id will be the creation id prefixed with a "#".)
      If this argument is not present in the request, the currently
      active SieveScript (if any) will remain as such.

      The id of any activated SieveScript MUST be reported in either the
      "created" or "updated" argument in the response as appropriate.
      The id of any deactivated SieveScript MUST be reported in the
      "updated" argument in the response.



   This method provides similar functionality to the PUTSCRIPT,
   DELETESCRIPT, RENAMESCRIPT, and SETACTIVE commands in [RFC5804].






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   Script content must first be uploaded as a blob using either the
   standard upload mechanism (see [RFC8620] Section 6.1) or the JMAP
   Blob management extension (see [I-D.gondwana-jmap-blob] Section 3.1).

   If the SieveScript can not be created or updated because it would
   result in two SieveScripts with the same name, the server MUST reject
   the request with an "alreadyExists" SetError.  An "existingId"
   property of type "Id" MUST be included on the SetError object with
   the id of the existing SieveScript.

   If the SieveScript can not be created or updated because its size
   exceeds the "maxSizeScript" limit, the server MUST reject the request
   with a "tooLarge" SetError.

   If the Sieve Script can not be created because it would exceed the
   "maxNumberScripts" limit, the server MUST reject the request with an
   "overQuota" SetError.

   The active SieveScript MUST NOT be destroyed unless it is first
   deactivated in a separate SieveScript/set method call.

   The following extra SetError types are defined:

   For "create" and "update":

   o  *invalidScript*:

      The SieveScript content violates the Sieve [RFC5228] grammar and/
      or one or more extensions mentioned in the script's "require"
      statement(s) are not supported by the Sieve interpreter.  The
      _description_ property on the SetError object SHOULD contain a
      specific error message giving at least the line number of the
      first error.



   For "destroy":

   o  *scriptIsActive*:

      The SieveScript is active.










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2.2.1.  Examples

   Request (and response) to upload a script requiring the Imap4Flags
   [RFC5232] Extension (assuming that the JMAP Upload URL has been
   advertised in the JMAP Session object as having a path of "/jmap/
   upload/{accountId}/"):

   POST /jmap/upload/ken/ HTTP/1.1
   Host: jmap.example.com
   Authorization: Basic a2VuOnBhc3N3b3Jk
   Content-Type: application/sieve
   Content-Length: 98

   require "imapflags";

   if address :is ["To", "Cc"] "jmap@ietf.org" {
     setflag "\\Flagged";
   }


   HTTP/1.1 201 Created
   Date: Thu, 10 Dec 2020 17:14:31 GMT
   Content-Type: application/json; charset=utf-8
   Content-Length: 171

   {
     "accountId": "ken",
     "blobId": "Gabcc83e44a6e19991c4568d0b94e1767c83dd123",
     "type": "application/sieve"
     "size": 98
   }




















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   Request (and response) to create and activate a script using the
   uploaded blob:

   {
     "using": [ "urn:ietf:params:jmap:core",
                "urn:ietf:params:jmap:sieve" ],
     "methodCalls": [
       ["SieveScript/set", {
         "accountId": "ken",
         "create": { "A": {
           "name": null,
           "blobId": "Gabcc83e44a6e19991c4568d0b94e1767c83dd123"
         },
         "onSuccessActivateScript": "#A"
       }, "0"]
     ]
   }

   {
     "methodResponses": [
       [
         "SieveScript/set",
         {
           "oldState": "1603741717.50737918-4096",
           "newState": "1603741751.227268529-4096",
           "created": {
             "A": {
               "id": "dd1b164f-8cdc-448c-9f54-60210b5f14ae",
               "name": "ken-20201210T171432-0",
               "blobId": "Sdd1b164f-8cdc-448c-9f54-60210b5f14ae",
               "isActive": true
             }
           },
           "updated": null,
           "destroyed": null,
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "0"
       ]
     ]
   }

   Request (and response) to update script content using the JMAP Blob
   management extension [I-D.gondwana-jmap-blob]:




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   {
     "using": [ "urn:ietf:params:jmap:core",
                "urn:ietf:params:jmap:sieve",
                "urn:ietf:params:jmap:blob" ],
     "methodCalls": [
       ["Blob/set", {
         "accountId": "ken",
         "create": { "B": {
           "data:asText": "redirect \"ken@example.com\"\r\n;",
           "type": "application/sieve"
         }
       }, "1"],
       ["SieveScript/set", {
         "accountId": "ken",
         "update": { "dd1b164f-8cdc-448c-9f54-60210b5f14ae": {
           "blobId": "#B"
           }
         }
       }, "2"]
     ]
   }

   {
     "methodResponses": [
       [
         "Blob/set",
         {
           "oldState": null,
           "newState": "1603741700.309607123-0128",
           "created": {
             "B": {
               "id": "G969c83e44a6e10871c4568d0b94e1767c83ddeae",
               "blobId": "G969c83e44a6e10871c4568d0b94e1767c83ddeae",
               "type": "application/sieve",
               "size": 29
             }
           },
           "updated": null,
           "destroyed": null,
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "1"
       ],
       [
         "SieveScript/set",



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         {
           "oldState": "1603741751.227268529-4096",
           "newState": "1603742603.309607868-4096",
           "created": null,
           "updated": {
             "dd1b164f-8cdc-448c-9f54-60210b5f14ae": null
           },
           "destroyed": null,
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "2"
       ]
     ]
   }


































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   Request (and response) to update script name and deactivate:

   {
     "using": [ "urn:ietf:params:jmap:core",
                "urn:ietf:params:jmap:sieve" ],
     "methodCalls": [
       ["SieveScript/set", {
         "accountId": "ken",
         "update": { "dd1b164f-8cdc-448c-9f54-60210b5f14ae": {
           "name": "myscript"
           }
         },
         "onSuccessActivateScript": null
       }, "3"]
     ]
   }

   {
     "methodResponses": [
       [
         "SieveScript/set",
         {
           "oldState": "1603742603.309607868-4096",
           "newState": "1603742967.852315428-4096",
           "created": null,
           "updated": {
             "dd1b164f-8cdc-448c-9f54-60210b5f14ae": {
               "isActive": false
             }
           },
           "destroyed": null,
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "3"
       ]
     ]
   }











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   Request (and response) to activate a script:

 {
   "using": [ "urn:ietf:params:jmap:core",
              "urn:ietf:params:jmap:sieve" ],
   "methodCalls": [
     ["SieveScript/set", {
       "accountId": "ken",
       "onSuccessActivateScript": "dd1b164f-8cdc-448c-9f54-60210b5f14ae"
     }, "4"]
   ]
 }

 {
   "methodResponses": [
     [
       "SieveScript/set",
       {
         "oldState": "1603742967.852315428-4096",
         "newState": "1603744460.316617118-4096",
         "created": null,
         "updated": {
           "dd1b164f-8cdc-448c-9f54-60210b5f14ae": {
             "isActive": true
           }
         },
         "destroyed": null,
         "notCreated": null,
         "notUpdated": null,
         "notDestroyed": null,
         "accountId": "ken"
       },
       "4"
     ]
   ]
 }

   Requests (and responses) to deactivate and destroy the active script:

   {
     "using": [ "urn:ietf:params:jmap:core",
                "urn:ietf:params:jmap:sieve" ],
     "methodCalls": [
       ["SieveScript/set", {
         "accountId": "ken",
         "onSuccessActivateScript": null
       }, "5"],
       ["SieveScript/set", {



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         "accountId": "ken",
         "destroy": [ "dd1b164f-8cdc-448c-9f54-60210b5f14ae" ]
       }, "6"]
     ]
   }

   {
     "methodResponses": [
       [
         "SieveScript/set",
         {
           "oldState": "1603744460.316617118-4096",
           "newState": "1603744637.575375572-4096",
           "created": null,
           "updated": null,
           "updated": {
             "dd1b164f-8cdc-448c-9f54-60210b5f14ae": {
               "isActive": false
             }
           },
           "destroyed": null,
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "5"
       ],
       [
         "SieveScript/set",
         {
           "oldState": "1603744637.575375572-4096",
           "newState": "1603744637.854390875-4096",
           "created": null,
           "updated": null,
           "destroyed": [
             "dd1b164f-8cdc-448c-9f54-60210b5f14ae"
           ],
           "notCreated": null,
           "notUpdated": null,
           "notDestroyed": null,
           "accountId": "ken"
         },
         "6"
       ]
     ]
   }




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2.3.  SieveScript/query

   This is a standard "/query" method as described in [RFC8620],
   Section 5.5.  A _FilterCondition_ object has the following
   properties, either of which may be omitted:

   o  *name*: "String"

      The SieveScript "name" property contains the given string.



   o  *isActive*: "Boolean"

      The "isActive" property of the SieveScript must be identical to
      the value given to match the condition.



   The following SieveScript properties MUST be supported for sorting:

   o  *name*



   o  *isActive*

2.4.  SieveScript/validate

   This method is used by the client to verify Sieve script validity
   without storing the script on the server, providing similar
   functionality to the CHECKSCRIPT command in [RFC5804].

   The method takes the following arguments:

   o  *accountId*: "Id"

      The id of the account to use.



   o  *blobId*: "Id"

      The id of the blob containing the raw octets of the script to
      validate, subject to the same requirements in Section 2.






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   The response has the following arguments:

   o  *accountId*: "Id"

      The id of the account used for this call.



   o  *error*: "SetError|null"

      A "invalidScript" SetError object if the script content is invalid
      (see Section 2.2), or "null" if the script content is valid.



   As with the SieveScript/set (Section 2.2) method, script content must
   first be uploaded as a blob using either the standard upload
   mechanism (see [RFC8620] Section 6.1) or the JMAP Blob management
   extension (see [I-D.gondwana-jmap-blob] Section 3.1).

2.5.  SieveScript/test

   This method is used by the client to ask the Sieve interpreter to
   evaluate a Sieve script against a set of emails and report the
   actions that would be performed for each.

   When calling this method the "using" property of the Request object
   MUST contain the capabilities "urn:ietf:params:jmap:sieve" and
   "urn:ietf:params:jmap:mail".  The latter is required due to the use
   of blob ids which may reference Email objects and the use of the
   Envelope object, as described below.

   The *SieveScript/test* method takes the following arguments:

   o  *accountId*: "Id"

      The id of the account to use.



   o  *scriptBlobId*: "String"

      The id of the blob containing the raw octets of the script to
      validate, subject to the same requirements in Section 2.



   o  *emailBlobIds*: "Id[]"



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      The ids representing the raw octets of the [RFC5322] messages to
      test against.



   o  *envelope*: "Envelope|null"

      Information that the Sieve interpreter should assume was present
      in the SMTP transaction that delivered the message when evaluating
      "envelope" tests.  If "null", all "envelope" tests MUST evaluate
      to false.  See Section 7 of [RFC8621] for the contents of the
      Envelope object.



   o  *lastVacationResponse*: "UTCDate|null"

      The UTC date-time at which the Sieve interpreter should assume
      that it last auto-replied to the sender of the message, or "null"
      if the Sieve interpreter should assume that it has not auto-
      replied to the sender.



   The response has the following arguments:

   o  *accountId*: "Id"

      The id of the account used for this call.



   o  *completed*: "Id[Action[]]|null"

      A map of the blob id to a set of _Action_ types for each message
      successfully processed by the script, or "null" if none.  The
      _Action_ data type is a tuple, represented as a JSON array
      containing two elements:



      1.  A "String" *name* of the Sieve action (e.g., "keep").



      2.  A "String[*]" object containing named *arguments* for that
          action (e.g., "flags" or "mailbox").




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   o  *notCompleted*: "Id[SetError]|null"

      A map of the blob id to a SetError object for each message that
      was not successfully processed by the script, or "null" if none.
      A "serverFail" SetError (see Section 3.6.2 of [RFC8620]) MUST be
      used to indicate a Sieve interpreter run-time error.



   The following additional errors may be returned instead of the
   "SieveScript/test" response:

   o  "invalidScript": The script content is invalid (see Section 2.2).

   o  "notFound": The script referenced by the id could not be found.

   o  "rateLimit": The number of recent test method calls has reached a
      server-defined limit.

   o  "requestTooLarge": The total number of emailBlobIds exceeds the
      maximum number the server is willing to process in a single test
      method call.

   o  "serverFail": The script failed preparation to be executed for
      some other reason.


   The name to use for each action argument in the response is a direct
   mapping of the argument names as given in the specification of each
   action.  Tagged and optional arguments MUST use the name of the tag,
   minus the leading ":".  Positional arguments MUST use the name of the
   argument inside of the angle brackets ("<" and ">") in the "Usage"
   line in the specification for the action.

   The JSON data type to use for each argument value is a direct mapping
   from its Sieve data type, per the following table:

                     +-------------+----------------+
                     |  Sieve Type |   JSON Type    |
                     +-------------+----------------+
                     |    Number   |     Number     |
                     |    String   |     String     |
                     | String List |    String[]    |
                     |   no value  | Boolean (true) |
                     +-------------+----------------+

   Recommendations for constructing the list of arguments are as
   follows:



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   o  Optional arguments in which the value is supplied by the Sieve
      interpreter SHOULD be included (e.g., ":from" and ":subject"
      arguments to the "vacation" [RFC5230] action).

   o  Optional arguments in which the value is implicitly supplied by a
      Sieve variable SHOULD be included (e.g., "keep" or "fileinto"
      actions without an explicit ":flags" argument, but "imap4flags"
      [RFC5232] have been set on the internal variable).

   o  Optional arguments in which the value is the specfied default MAY
      be omitted.

   o  Tagged arguments that are only used to determine whether the
      action will be executed and have no impact on the result of the
      action MAY be omitted (e.g., ":days" and ":addresses" arguments to
      the vacation action).

2.5.1.  Example

   Assume that the following script has been created and has blob id
   "S123".

   require [ "imapflags", "editheader", "vacation", "fcc" ];
   setflag "$SieveFiltered";
   addheader :last "X-Sieve-Filtered" "yes";
   vacation :days 3 :fcc "INBOX.Sent" :flags "\\Answered" text:
   Gone fishing.
   .
   ;

   Assume that the following email has been uploaded and assigned blob
   id "B456".

   From: "Some Example Sender" <example@example.net>
   To: ken@example.com
   Subject: test email
   Date: Wed, 23 Sep 2020 12:11:11 -0500
   Content-Type: text/plain; charset="UTF-8"
   MIME-Version: 1.0

   This is a test email.










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   The following request executes the script against the email and
   provides envelope information for use by the "vacation" action.

   {
     "using": [
       "urn:ietf:params:jmap:core",
       "urn:ietf:params:jmap:sieve",
       "urn:ietf:params:jmap:mail"
     ],
     "methodCalls": [
       [
         "SieveScript/test",
         {
           "accountId": "ken",
           "scriptBlobId": "S123",
           "emailBlobIds": [
             "B456"
           ],
           "envelope": {
             "mailFrom": {
               "email": "example@example.net",
               "parameters": null
             },
             "rcptTo": [
               {
                 "email": "ken@example.com",
                 "parameters": null
               }
             ]
           },
           "lastVacationResponse": null
         },
         "R1"
       ]
     ]
   }















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   The following response lists the actions that would be performed by
   the script.

   {
     "methodResponses": [
       [
         "SieveScript/test",
         {
           "completed": {
             "B456": [
               [
                 "addheader",
                 {
                   "last": true,
                   "field-name": "X-Sieve-Filtered",
                   "value": "yes"
                 }
               ],
               [
                 "vacation",
                 {
                   "fcc": "INBOX.Sent",
                   "flags": [
                     "\\answered"
                   ],
                   "subject": "Auto: test email",
                   "from": "ken@example.com",
                   "reason": "Gone fishing."
                 }
               ],
               [
                 "keep",
                 {
                   "flags": [
                     "$SieveFiltered"
                   ]
                 }
               ]
             ]
           },
           "notCompleted": null,
           "accountId": "ken",
         },
         "R1"
       ]
     ]
   }




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3.  Compatibility with JMAP Vacation Response

   Section 8 of [RFC8621] defines a VacationResponse object to represent
   an autoresponder to incoming email messages.  Servers that implement
   the VacationResponse as a Sieve script that resides amongst other
   user scripts are subject to the following requirements:

   o  MUST allow the VacationResponse Sieve script to be fetched by the
      SieveScript/get (Section 2.1) method.

   o  MUST allow the VacationResponse Sieve script to be [de]activated
      via the "onSuccessActivateScript" argument to the SieveScript/set
      (Section 2.2) method.

   o  MUST NOT allow the VacationResponse Sieve script to be destroyed
      or have its content updated by the SieveScript/set (Section 2.2)
      method.  Any such request MUST be rejected with a "forbidden"
      SetError.  A "description" property MAY be present with an
      explanation that the script can only be modified by a
      VacationResponse/set method.

4.  Security Considerations

   All security considerations of JMAP [RFC8620] and Sieve [RFC5228]
   apply to this specification.

5.  IANA Considerations

5.1.  JMAP Capability Registration for "sieve"

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

   Capability Name: "urn:ietf:params:jmap:sieve"

   Specification document: this document

   Intended use: common

   Change Controller: IETF

   Security and privacy considerations: this document, Section 4

5.2.  JMAP Error Codes Registry

   The following sub-sections register two new error codes in the JMAP
   Error Codes registry, as defined in [RFC8620].





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5.2.1.  invalidScript

   JMAP Error Code: invalidScript

   Intended use: common

   Change controller: IETF

   Reference: This document, Section 2.2

   Description: The SieveScript violates the Sieve grammar [RFC5228]
   and/or one or more extensions mentioned in the script's "require"
   statement(s) are not supported by the Sieve interpreter.

5.2.2.  scriptIsActive

   JMAP Error Code: scriptIsActive

   Intended use: common

   Change controller: IETF

   Reference: This document, Section 2.2

   Description: The client tried to destroy the active SieveScript.

6.  Acknowledgments

   The concepts in this document are based largely on those in
   [RFC5804].  The author would like to thank the authors of that
   document for providing both inspiration and some borrowed text for
   this document.

   The author would also like to thank the following individuals for
   contributing their ideas and support for writing this specification:
   Bron Gondwana, Neil Jenkins, Alexey Melnikov, and Ricardo Signes.

7.  References

7.1.  Normative References

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






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   [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO
              10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
              2003, <https://www.rfc-editor.org/info/rfc3629>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.

   [RFC5198]  Klensin, J. and M. Padlipsky, "Unicode Format for Network
              Interchange", RFC 5198, DOI 10.17487/RFC5198, March 2008,
              <https://www.rfc-editor.org/info/rfc5198>.

   [RFC5228]  Guenther, P., Ed. and T. Showalter, Ed., "Sieve: An Email
              Filtering Language", RFC 5228, DOI 10.17487/RFC5228,
              January 2008, <https://www.rfc-editor.org/info/rfc5228>.

   [RFC5322]  Resnick, P., Ed., "Internet Message Format", RFC 5322,
              DOI 10.17487/RFC5322, October 2008,
              <https://www.rfc-editor.org/info/rfc5322>.

   [RFC5435]  Melnikov, A., Ed., Leiba, B., Ed., Segmuller, W., and T.
              Martin, "Sieve Email Filtering: Extension for
              Notifications", RFC 5435, DOI 10.17487/RFC5435, January
              2009, <https://www.rfc-editor.org/info/rfc5435>.

   [RFC6134]  Melnikov, A. and B. Leiba, "Sieve Extension: Externally
              Stored Lists", RFC 6134, DOI 10.17487/RFC6134, July 2011,
              <https://www.rfc-editor.org/info/rfc6134>.

   [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>.

   [RFC8621]  Jenkins, N. and C. Newman, "The JSON Meta Application
              Protocol (JMAP) for Mail", RFC 8621, DOI 10.17487/RFC8621,
              August 2019, <https://www.rfc-editor.org/info/rfc8621>.

7.2.  Informative References

   [I-D.gondwana-jmap-blob]
              Gondwana, B., "JMAP Blob management extension", draft-
              gondwana-jmap-blob-01 (work in progress), November 2020.




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   [RFC5230]  Showalter, T. and N. Freed, Ed., "Sieve Email Filtering:
              Vacation Extension", RFC 5230, DOI 10.17487/RFC5230,
              January 2008, <https://www.rfc-editor.org/info/rfc5230>.

   [RFC5232]  Melnikov, A., "Sieve Email Filtering: Imap4flags
              Extension", RFC 5232, DOI 10.17487/RFC5232, January 2008,
              <https://www.rfc-editor.org/info/rfc5232>.

   [RFC5463]  Freed, N., "Sieve Email Filtering: Ihave Extension",
              RFC 5463, DOI 10.17487/RFC5463, March 2009,
              <https://www.rfc-editor.org/info/rfc5463>.

   [RFC5804]  Melnikov, A., Ed. and T. Martin, "A Protocol for Remotely
              Managing Sieve Scripts", RFC 5804, DOI 10.17487/RFC5804,
              July 2010, <https://www.rfc-editor.org/info/rfc5804>.

Appendix A.  Change History (To be removed by RFC Editor before
             publication)

   Changes since ietf-02:

   o  Removed open issues.

   o  Reverted back to using only blob ids for script content.

   o  Added "rateLimit" and "requestTooLarge" to the list of possible
      error codes for /set method.

   o  Added Compatibility with JMAP Vacation Response section.

   o  Added RFC5228 to Security Considerations.

   o  Miscellaneous editorial changes.

   Changes since ietf-01:

   o  Removed normative references to ManageSieve (RFC 5804).

   o  Added the 'maxSizeScriptName' capability.

   o  Made the 'name' property in the SieveScript object optional.

   o  Added requirements for the 'name' property in the SieveScript
      object.

   o  Removed the 'blobId' property from the SieveScript object.

   o  Removed the 'replaceOnCreate' argument from the /set method.



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   o  Removed the 'blobId' argument from the /validate method.

   o  Removed the 'scriptBlobId' argument from, and added the
      'scriptContent' argument to, the /test method.

   o  Editorial fixes from Neil Jenkins and Ricardo Signes.

   o  Other miscellaneous text reorganization and editorial fixes.

   Changes since ietf-00:

   o  Specified that changes made by onSuccessActivateScript MUST be
      reported in the /set response as created and/or updated as
      appropriate.

   o  Reworked and specified more of the /test response based on
      implementation experience.

   Changes since murchison-01:

   o  Explicitly stated that Sieve capability strings are case-
      sensitive.

   o  errorDescription is now String|null.

   o  Added /query method.

   o  Added /test method.

   Changes since murchison-00:

   o  Added IANA registration for "scriptIsActive" JMAP error code.

   o  Added open issue about /set{create} with an existing script name.

Author's Address

   Kenneth Murchison
   Fastmail US LLC
   1429 Walnut Street - Suite 1201
   Philadelphia, PA  19102
   USA

   Email: murch@fastmailteam.com







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