1.  Introduction

   This document describes a protocol for interacting with Transmission
   sessions remotely.

1.1  Terminology

   The JSON terminology in RFC 4627 is used.

   JSON is fairly common now, but for the benefit of
   torrent developers familiar with benc:
   a JSON array is equivalent to a benc list,
   a JSON object is equivalent to a benc dictionary,
   and a JSON object's keys are the dictionary's string keys.

1.2  Resources

   The command-line utility "transmission-remote" uses this RPC API.
   Several developers have reported using its --debug JSON output as
   a reference when developing/debugging their own code.
   
2.  Message Format

   Messages are formatted as objects.  There are two types:
   requests (described in 2.1) and responses (described in 2.2).

   All text MUST be UTF-8 encoded.

2.1.  Requests

   Requests support three keys:

   (1) A required "method" string telling the name of the method to invoke
   (2) An optional "arguments" object of key/value pairs
   (3) An optional "tag" number used by clients to track responses.
       If provided by a request, the response MUST include the same tag.

2.2.  Responses

   Reponses support three keys:

   (1) A required "result" string whose value MUST be "success" on success,
       or an error string on failure.
   (2) An optional "arguments" object of key/value pairs
   (3) An optional "tag" number as described in 2.1.

2.3.  Transport Mechanism

   HTTP POSTing a JSON-encoded request is the preferred way of communicating
   with a Transmission RPC server.  The current Transmission implementation
   has the default URL as http://host:9091/transmission/rpc.  Clients
   may use this as a default, but should allow the URL to be reconfigured,
   since the port and path may be changed to allow mapping and/or multiple
   daemons to run on a single server.

2.3.1.  CSRF Protection

   Most Transmission RPC servers require a X-Transmission-Session-Id
   header to be sent with requests, to prevent CSRF attacks.

   When your request has the wrong id -- such as when you send your first
   request, or when the server expires the CSRF token -- the
   Transmission RPC server will return an HTTP 409 error with the
   right X-Transmission-Session-Id in its own headers.

   So, the correct way to handle a 409 response is to update your
   X-Transmission-Session-Id and to resend the previous request.

3.  Torrent Requests

3.1.  Torrent Action Requests

   Method name          | libtransmission function
   ---------------------+-------------------------------------------------
   "torrent-start"      | tr_torrentStart
   "torrent-start-now"  | tr_torrentStartNow
   "torrent-stop"       | tr_torrentStop
   "torrent-verify"     | tr_torrentVerify
   "torrent-reannounce" | tr_torrentManualUpdate ("ask tracker for more peers")

   Request arguments: "ids", which specifies which torrents to use.
                  All torrents are used if the "ids" argument is omitted.
                  "ids" should be one of the following:
                  (1) an integer referring to a torrent id
                  (2) a list of torrent id numbers, sha1 hash strings, or both
                  (3) a string, "recently-active", for recently-active torrents

   Response arguments: none

3.2.  Torrent Mutators

   Method name: "torrent-set"

   Request arguments:

   string                | value type & description
   ----------------------+-------------------------------------------------
   "bandwidthPriority"   | number     this torrent's bandwidth tr_priority_t
   "downloadLimit"       | number     maximum download speed (KBps)
   "downloadLimited"     | boolean    true if "downloadLimit" is honored
   "files-wanted"        | array      indices of file(s) to download
   "files-unwanted"      | array      indices of file(s) to not download
   "honorsSessionLimits" | boolean    true if session upload limits are honored
   "ids"                 | array      torrent list, as described in 3.1
   "location"            | string     new location of the torrent's content
   "peer-limit"          | number     maximum number of peers
   "priority-high"       | array      indices of high-priority file(s)
   "priority-low"        | array      indices of low-priority file(s)
   "priority-normal"     | array      indices of normal-priority file(s)
   "queuePosition"       | number     position of this torrent in its queue [0...n)
   "seedIdleLimit"       | number     torrent-level number of minutes of seeding inactivity
   "seedIdleMode"        | number     which seeding inactivity to use.  See tr_idlelimit
   "seedRatioLimit"      | double     torrent-level seeding ratio
   "seedRatioMode"       | number     which ratio to use.  See tr_ratiolimit
   "trackerAdd"          | array      strings of announce URLs to add
   "trackerRemove"       | array      ids of trackers to remove
   "trackerReplace"      | array      pairs of <trackerId/new announce URLs>
   "uploadLimit"         | number     maximum upload speed (KBps)
   "uploadLimited"       | boolean    true if "uploadLimit" is honored

   Just as an empty "ids" value is shorthand for "all ids", using an empty array
   for "files-wanted", "files-unwanted", "priority-high", "priority-low", or
   "priority-normal" is shorthand for saying "all files".

   Response arguments: none

3.3.  Torrent Accessors

   Method name: "torrent-get".

   Request arguments:

   (1) An optional "ids" array as described in 3.1.
   (2) A required "fields" array of keys. (see list below)

   Response arguments:

   (1) A "torrents" array of objects, each of which contains
       the key/value pairs matching the request's "fields" argument.
   (2) If the request's "ids" field was "recently-active",
       a "removed" array of torrent-id numbers of recently-removed
       torrents.

   Note: For more information on what these fields mean, see the comments
   in libtransmission/transmission.h.  The "source" column here
   corresponds to the data structure there.

   key                         | type                        | source 
   ----------------------------+-----------------------------+---------
   activityDate                | number                      | tr_stat
   addedDate                   | number                      | tr_stat
   bandwidthPriority           | number                      | tr_priority_t
   comment                     | string                      | tr_info
   corruptEver                 | number                      | tr_stat
   creator                     | string                      | tr_info
   dateCreated                 | number                      | tr_info
   desiredAvailable            | number                      | tr_stat
   doneDate                    | number                      | tr_stat
   downloadDir                 | string                      | tr_torrent
   downloadedEver              | number                      | tr_stat
   downloadLimit               | number                      | tr_torrent
   downloadLimited             | boolean                     | tr_torrent
   error                       | number                      | tr_stat
   errorString                 | string                      | tr_stat
   eta                         | number                      | tr_stat
   etaIdle                     | number                      | tr_stat
   files                       | array (see below)           | n/a
   fileStats                   | array (see below)           | n/a
   hashString                  | string                      | tr_info
   haveUnchecked               | number                      | tr_stat
   haveValid                   | number                      | tr_stat
   honorsSessionLimits         | boolean                     | tr_torrent
   id                          | number                      | tr_torrent
   isFinished                  | boolean                     | tr_stat
   isPrivate                   | boolean                     | tr_torrent
   isStalled                   | boolean                     | tr_stat
   leftUntilDone               | number                      | tr_stat
   magnetLink                  | string                      | n/a
   manualAnnounceTime          | number                      | tr_stat
   maxConnectedPeers           | number                      | tr_torrent
   metadataPercentComplete     | double                      | tr_stat
   name                        | string                      | tr_info
   peer-limit                  | number                      | tr_torrent
   peers                       | array (see below)           | n/a
   peersConnected              | number                      | tr_stat
   peersFrom                   | object (see below)          | n/a
   peersGettingFromUs          | number                      | tr_stat
   peersSendingToUs            | number                      | tr_stat
   percentDone                 | double                      | tr_stat
   pieces                      | string (see below)          | tr_torrent
   pieceCount                  | number                      | tr_info
   pieceSize                   | number                      | tr_info
   priorities                  | array (see below)           | n/a
   queuePosition               | number                      | tr_stat
   rateDownload (B/s)          | number                      | tr_stat
   rateUpload (B/s)            | number                      | tr_stat
   recheckProgress             | double                      | tr_stat
   secondsDownloading          | number                      | tr_stat
   secondsSeeding              | number                      | tr_stat
   seedIdleLimit               | number                      | tr_torrent
   seedIdleMode                | number                      | tr_inactvelimit
   seedRatioLimit              | double                      | tr_torrent
   seedRatioMode               | number                      | tr_ratiolimit
   sizeWhenDone                | number                      | tr_stat
   startDate                   | number                      | tr_stat
   status                      | number                      | tr_stat
   trackers                    | array (see below)           | n/a
   trackerStats                | array (see below)           | n/a
   totalSize                   | number                      | tr_info
   torrentFile                 | string                      | tr_info
   uploadedEver                | number                      | tr_stat
   uploadLimit                 | number                      | tr_torrent
   uploadLimited               | boolean                     | tr_torrent
   uploadRatio                 | double                      | tr_stat
   wanted                      | array (see below)           | n/a
   webseeds                    | array (see below)           | n/a
   webseedsSendingToUs         | number                      | tr_stat
                               |                             |
                               |                             |
   -------------------+--------+-----------------------------+
   files              | array of objects, each containing:   |
                      +-------------------------+------------+
                      | bytesCompleted          | number     | tr_torrent
                      | length                  | number     | tr_info
                      | name                    | string     | tr_info
   -------------------+--------------------------------------+
   fileStats          | a file's non-constant properties.    |
                      | array of tr_info.filecount objects,  |
                      | each containing:                     |
                      +-------------------------+------------+
                      | bytesCompleted          | number     | tr_torrent
                      | wanted                  | boolean    | tr_info
                      | priority                | number     | tr_info
   -------------------+--------------------------------------+
   peers              | array of objects, each containing:   |
                      +-------------------------+------------+
                      | address                 | string     | tr_peer_stat
                      | clientName              | string     | tr_peer_stat
                      | clientIsChoked          | boolean    | tr_peer_stat
                      | clientIsInterested      | boolean    | tr_peer_stat
                      | flagStr                 | string     | tr_peer_stat
                      | isDownloadingFrom       | boolean    | tr_peer_stat
                      | isEncrypted             | boolean    | tr_peer_stat
                      | isIncoming              | boolean    | tr_peer_stat
                      | isUploadingTo           | boolean    | tr_peer_stat
                      | isUTP                   | boolean    | tr_peer_stat
                      | peerIsChoked            | boolean    | tr_peer_stat
                      | peerIsInterested        | boolean    | tr_peer_stat
                      | port                    | number     | tr_peer_stat
                      | progress                | double     | tr_peer_stat
                      | rateToClient (B/s)      | number     | tr_peer_stat
                      | rateToPeer (B/s)        | number     | tr_peer_stat
   -------------------+--------------------------------------+
   peersFrom          | an object containing:                |
                      +-------------------------+------------+
                      | fromCache               | number     | tr_stat
                      | fromDht                 | number     | tr_stat
                      | fromIncoming            | number     | tr_stat
                      | fromLpd                 | number     | tr_stat
                      | fromLtep                | number     | tr_stat
                      | fromPex                 | number     | tr_stat
                      | fromTracker             | number     | tr_stat
   -------------------+--------------------------------------+
   pieces             | A bitfield holding pieceCount flags  | tr_torrent
                      | which are set to 'true' if we have   |
                      | the piece matching that position.    |
                      | JSON doesn't allow raw binary data,  |
                      | so this is a base64-encoded string.  |
   -------------------+--------------------------------------+
   priorities         | an array of tr_info.filecount        | tr_info
                      | numbers. each is the tr_priority_t   |
                      | mode for the corresponding file.     |
   -------------------+--------------------------------------+
   trackers           | array of objects, each containing:   |
                      +-------------------------+------------+
                      | announce                | string     | tr_tracker_info
                      | id                      | number     | tr_tracker_info
                      | scrape                  | string     | tr_tracker_info
                      | tier                    | number     | tr_tracker_info
   -------------------+--------------------------------------+
   trackerStats       | array of objects, each containing:   |
                      +-------------------------+------------+
                      | announce                | string     | tr_tracker_stat
                      | announceState           | number     | tr_tracker_stat
                      | downloadCount           | number     | tr_tracker_stat
                      | hasAnnounced            | boolean    | tr_tracker_stat
                      | hasScraped              | boolean    | tr_tracker_stat
                      | host                    | string     | tr_tracker_stat
                      | id                      | number     | tr_tracker_stat
                      | isBackup                | boolean    | tr_tracker_stat
                      | lastAnnouncePeerCount   | number     | tr_tracker_stat
                      | lastAnnounceResult      | string     | tr_tracker_stat
                      | lastAnnounceStartTime   | number     | tr_tracker_stat
                      | lastAnnounceSucceeded   | boolean    | tr_tracker_stat
                      | lastAnnounceTime        | number     | tr_tracker_stat
                      | lastAnnounceTimedOut    | boolean    | tr_tracker_stat
                      | lastScrapeResult        | string     | tr_tracker_stat
                      | lastScrapeStartTime     | number     | tr_tracker_stat
                      | lastScrapeSucceeded     | boolean    | tr_tracker_stat
                      | lastScrapeTime          | number     | tr_tracker_stat
                      | lastScrapeTimedOut      | boolean    | tr_tracker_stat
                      | leecherCount            | number     | tr_tracker_stat
                      | nextAnnounceTime        | number     | tr_tracker_stat
                      | nextScrapeTime          | number     | tr_tracker_stat
                      | scrape                  | string     | tr_tracker_stat
                      | scrapeState             | number     | tr_tracker_stat
                      | seederCount             | number     | tr_tracker_stat
                      | tier                    | number     | tr_tracker_stat
   -------------------+-------------------------+------------+
   wanted             | an array of tr_info.fileCount        | tr_info
                      | 'booleans' true if the corresponding |
                      | file is to be downloaded.            |
   -------------------+--------------------------------------+
   webseeds           | an array of strings:                 |
                      +-------------------------+------------+
                      | webseed                 | string     | tr_info
                      +-------------------------+------------+

   Example:

   Say we want to get the name and total size of torrents #7 and #10.

   Request: 

      {
         "arguments": {
             "fields": [ "id", "name", "totalSize" ],
             "ids": [ 7, 10 ]
         },
         "method": "torrent-get",
         "tag": 39693
      }


   Response:

      {
         "arguments": {
            "torrents": [ 
               { 
                   "id": 10,
                   "name": "Fedora x86_64 DVD",
                   "totalSize": 34983493932,
               },
               {
                   "id": 7,
                   "name": "Ubuntu x86_64 DVD",
                   "totalSize", 9923890123,
               } 
            ]
         },
         "result": "success",
         "tag": 39693
      }

3.4.  Adding a Torrent

   Method name: "torrent-add"

   Request arguments:

   key                  | value type & description
   ---------------------+-------------------------------------------------
   "cookies"            | string      pointer to a string of one or more cookies.
   "download-dir"       | string      path to download the torrent to
   "filename"           | string      filename or URL of the .torrent file
   "metainfo"           | string      base64-encoded .torrent content
   "paused"             | boolean     if true, don't start the torrent
   "peer-limit"         | number      maximum number of peers
   "bandwidthPriority"  | number      torrent's bandwidth tr_priority_t 
   "files-wanted"       | array       indices of file(s) to download
   "files-unwanted"     | array       indices of file(s) to not download
   "priority-high"      | array       indices of high-priority file(s)
   "priority-low"       | array       indices of low-priority file(s)
   "priority-normal"    | array       indices of normal-priority file(s)

   Either "filename" OR "metainfo" MUST be included.
   All other arguments are optional.

   The format of the "cookies" should be NAME=CONTENTS, where NAME is the
   cookie name and CONTENTS is what the cookie should contain.
   Set multiple cookies like this: "name1=content1; name2=content2;" etc. 
   <http://curl.haxx.se/libcurl/c/curl_easy_setopt.html#CURLOPTCOOKIE>

   Response arguments: On success, a "torrent-added" object in the
                       form of one of 3.3's tr_info objects with the
                       fields for id, name, and hashString.

                       On failure due to a duplicate torrent existing,
                       a "torrent-duplicate" object in the same form.

3.5.  Removing a Torrent

   Method name: "torrent-remove"

   Request arguments:

   string                     | value type & description
   ---------------------------+-------------------------------------------------
   "ids"                      | array      torrent list, as described in 3.1
   "delete-local-data"        | boolean    delete local data. (default: false)

   Response arguments: none


3.6.  Moving a Torrent

   Method name: "torrent-set-location"

   Request arguments:

   string                           | value type & description
   ---------------------------------+-------------------------------------------------
   "ids"                            | array      torrent list, as described in 3.1
   "location"                       | string     the new torrent location
   "move"                           | boolean    if true, move from previous location.
                                    |            otherwise, search "location" for files
                                    |            (default: false)

   Response arguments: none


3.7.  Renaming a Torrent's Path

   Method name: "torrent-rename-path"

   For more information on the use of this function, see the transmission.h
   documentation of tr_torrentRenamePath(). In particular, note that if this
   call succeeds you'll want to update the torrent's "files" and "name" field
   with torrent-get.

   Request arguments:

   string                           | value type & description
   ---------------------------------+-------------------------------------------------
   "ids"                            | array      the torrent torrent list, as described in 3.1
                                    |            (must only be 1 torrent)
   "path"                           | string     the path to the file or folder that will be renamed
   "name"                           | string     the file or folder's new name

   Response arguments: "path", "name", and "id", holding the torrent ID integer


4.   Session Requests

4.1.  Session Arguments

   string                           | value type | description
   ---------------------------------+------------+-------------------------------------
   "alt-speed-down"                 | number     | max global download speed (KBps)
   "alt-speed-enabled"              | boolean    | true means use the alt speeds
   "alt-speed-time-begin"           | number     | when to turn on alt speeds (units: minutes after midnight)
   "alt-speed-time-enabled"         | boolean    | true means the scheduled on/off times are used
   "alt-speed-time-end"             | number     | when to turn off alt speeds (units: same)
   "alt-speed-time-day"             | number     | what day(s) to turn on alt speeds (look at tr_sched_day)
   "alt-speed-up"                   | number     | max global upload speed (KBps)
   "blocklist-url"                  | string     | location of the blocklist to use for "blocklist-update"
   "blocklist-enabled"              | boolean    | true means enabled
   "blocklist-size"                 | number     | number of rules in the blocklist
   "cache-size-mb"                  | number     | maximum size of the disk cache (MB)
   "config-dir"                     | string     | location of transmission's configuration directory
   "download-dir"                   | string     | default path to download torrents
   "download-queue-size"            | number     | max number of torrents to download at once (see download-queue-enabled)
   "download-queue-enabled"         | boolean    | if true, limit how many torrents can be downloaded at once
   "dht-enabled"                    | boolean    | true means allow dht in public torrents
   "encryption"                     | string     | "required", "preferred", "tolerated"
   "idle-seeding-limit"             | number     | torrents we're seeding will be stopped if they're idle for this long
   "idle-seeding-limit-enabled"     | boolean    | true if the seeding inactivity limit is honored by default
   "incomplete-dir"                 | string     | path for incomplete torrents, when enabled
   "incomplete-dir-enabled"         | boolean    | true means keep torrents in incomplete-dir until done
   "lpd-enabled"                    | boolean    | true means allow Local Peer Discovery in public torrents
   "peer-limit-global"              | number     | maximum global number of peers
   "peer-limit-per-torrent"         | number     | maximum global number of peers
   "pex-enabled"                    | boolean    | true means allow pex in public torrents
   "peer-port"                      | number     | port number
   "peer-port-random-on-start"      | boolean    | true means pick a random peer port on launch
   "port-forwarding-enabled"        | boolean    | true means enabled
   "queue-stalled-enabled"          | boolean    | whether or not to consider idle torrents as stalled
   "queue-stalled-minutes"          | number     | torrents that are idle for N minuets aren't counted toward seed-queue-size or download-queue-size
   "rename-partial-files"           | boolean    | true means append ".part" to incomplete files
   "rpc-version"                    | number     | the current RPC API version
   "rpc-version-minimum"            | number     | the minimum RPC API version supported
   "script-torrent-done-filename"   | string     | filename of the script to run
   "script-torrent-done-enabled"    | boolean    | whether or not to call the "done" script
   "seedRatioLimit"                 | double     | the default seed ratio for torrents to use
   "seedRatioLimited"               | boolean    | true if seedRatioLimit is honored by default
   "seed-queue-size"                | number     | max number of torrents to uploaded at once (see seed-queue-enabled)
   "seed-queue-enabled"             | boolean    | if true, limit how many torrents can be uploaded at once
   "speed-limit-down"               | number     | max global download speed (KBps)
   "speed-limit-down-enabled"       | boolean    | true means enabled
   "speed-limit-up"                 | number     | max global upload speed (KBps)
   "speed-limit-up-enabled"         | boolean    | true means enabled
   "start-added-torrents"           | boolean    | true means added torrents will be started right away
   "trash-original-torrent-files"   | boolean    | true means the .torrent file of added torrents will be deleted
   "units"                          | object     | see below
   "utp-enabled"                    | boolean    | true means allow utp
   "version"                        | string     | long version string "$version ($revision)"
   ---------------------------------+------------+-----------------------------+
   units                            | object containing:                       |
                                    +--------------+--------+------------------+
                                    | speed-units  | array  | 4 strings: KB/s, MB/s, GB/s, TB/s
                                    | speed-bytes  | number | number of bytes in a KB (1000 for kB; 1024 for KiB)
                                    | size-units   | array  | 4 strings: KB/s, MB/s, GB/s, TB/s
                                    | size-bytes   | number | number of bytes in a KB (1000 for kB; 1024 for KiB)
                                    | memory-units | array  | 4 strings: KB/s, MB/s, GB/s, TB/s
                                    | memory-bytes | number | number of bytes in a KB (1000 for kB; 1024 for KiB)
                                    +--------------+--------+------------------+

   "rpc-version" indicates the RPC interface version supported by the RPC server.
   It is incremented when a new version of Transmission changes the RPC interface.

   "rpc-version-minimum" indicates the oldest API supported by the RPC server.
   It is changes when a new version of Transmission changes the RPC interface
   in a way that is not backwards compatible.  There are no plans for this
   to be common behavior.

4.1.1.  Mutators

   Method name: "session-set"
   Request arguments: one or more of 4.1's arguments, except: "blocklist-size",
                      "config-dir", "rpc-version", "rpc-version-minimum", and
                      "version"
   Response arguments: none

4.1.2.  Accessors

   Method name: "session-get"
   Request arguments: none
   Response arguments: all of 4.1's arguments

4.2.  Session Statistics

   Method name: "session-stats"

   Request arguments: none

   Response arguments:

   string                     | value type
   ---------------------------+-------------------------------------------------
   "activeTorrentCount"       | number
   "downloadSpeed"            | number
   "pausedTorrentCount"       | number
   "torrentCount"             | number
   "uploadSpeed"              | number
   ---------------------------+-------------------------------+
   "cumulative-stats"         | object, containing:           |
                              +------------------+------------+
                              | uploadedBytes    | number     | tr_session_stats
                              | downloadedBytes  | number     | tr_session_stats
                              | filesAdded       | number     | tr_session_stats
                              | sessionCount     | number     | tr_session_stats
                              | secondsActive    | number     | tr_session_stats
   ---------------------------+-------------------------------+
   "current-stats"            | object, containing:           |
                              +------------------+------------+
                              | uploadedBytes    | number     | tr_session_stats
                              | downloadedBytes  | number     | tr_session_stats
                              | filesAdded       | number     | tr_session_stats
                              | sessionCount     | number     | tr_session_stats
                              | secondsActive    | number     | tr_session_stats

4.3.  Blocklist

   Method name: "blocklist-update"
   Request arguments: none
   Response arguments: a number "blocklist-size"

4.4.  Port Checking

   This method tests to see if your incoming peer port is accessible
   from the outside world.

   Method name: "port-test"
   Request arguments: none
   Response arguments: a bool, "port-is-open"

4.5.  Session shutdown

   This method tells the transmission session to shut down.

   Method name: "session-close"
   Request arguments: none
   Response arguments: none

4.6.  Queue Movement Requests

   Method name          | libtransmission function
   ---------------------+-------------------------------------------------
   "queue-move-top"     | tr_torrentQueueMoveTop()
   "queue-move-up"      | tr_torrentQueueMoveUp()
   "queue-move-down"    | tr_torrentQueueMoveDown()
   "queue-move-bottom"  | tr_torrentQueueMoveBottom()

   Request arguments:

   string      | value type & description
   ------------+----------------------------------------------------------
   "ids"       | array   torrent list, as described in 3.1.

   Response arguments: none

4.7.  Free Space

   This method tests how much free space is available in a
   client-specified folder.

   Method name: "free-space"

   Request arguments:

   string      | value type & description
   ------------+----------------------------------------------------------
   "path"      | string  the directory to query

   Response arguments:

   string      | value type & description
   ------------+----------------------------------------------------------
   "path"      | string  same as the Request argument
   "size-bytes"| number  the size, in bytes, of the free space in that directory


5.0.  Protocol Versions

  The following changes have been made to the RPC interface:

   RPC   | Release | Backwards |                      |
   Vers. | Version | Compat?   | Method               | Description
   ------+---------+-----------+----------------------+-------------------------------
   1     | 1.30    | n/a       | n/a                  | Initial version
   ------+---------+-----------+----------------------+-------------------------------
   2     | 1.34    | yes       | torrent-get          | new arg "peers"
   ------+---------+-----------+----------------------+-------------------------------
   3     | 1.41    | yes       | torrent-get          | added "port" to "peers"
         |         | yes       | torrent-get          | new arg "downloaders"
         |         | yes       | session-get          | new arg "version"
         |         | yes       | torrent-remove       | new method
   ------+---------+-----------+----------------------+-------------------------------
   4     | 1.50    | yes       | session-get          | new arg "rpc-version"
         |         | yes       | session-get          | new arg "rpc-version-minimum"
         |         | yes       | session-stats        | added "cumulative-stats"
         |         | yes       | session-stats        | added "current-stats"
         |         | yes       | torrent-get          | new arg "downloadDir"
   ------+---------+-----------+----------------------+-------------------------------
   5     | 1.60    | yes       |                      | new method "torrent-reannounce"
         |         | yes       |                      | new method "blocklist-update"
         |         | yes       |                      | new method "port-test"
         |         |           |                      |
         |         | yes       | session-get          | new arg "alt-speed-begin"
         |         | yes       | session-get          | new arg "alt-speed-down"
         |         | yes       | session-get          | new arg "alt-speed-enabled"
         |         | yes       | session-get          | new arg "alt-speed-end"
         |         | yes       | session-get          | new arg "alt-speed-time-enabled"
         |         | yes       | session-get          | new arg "alt-speed-up"
         |         | yes       | session-get          | new arg "blocklist-enabled"
         |         | yes       | session-get          | new arg "blocklist-size"
         |         | yes       | session-get          | new arg "peer-limit-per-torrent"
         |         | yes       | session-get          | new arg "seedRatioLimit"
         |         | yes       | session-get          | new arg "seedRatioLimited"
         |         |        NO | session-get          | renamed "pex-allowed" to "pex-enabled"
         |         |        NO | session-get          | renamed "port" to "peer-port"
         |         |        NO | session-get          | renamed "peer-limit" to "peer-limit-global"
         |         |           |                      |
         |         | yes       | torrent-add          | new arg "files-unwanted"
         |         | yes       | torrent-add          | new arg "files-wanted"
         |         | yes       | torrent-add          | new arg "priority-high"
         |         | yes       | torrent-add          | new arg "priority-low"
         |         | yes       | torrent-add          | new arg "priority-normal"
         |         |           |                      |
         |         | yes       | torrent-set          | new arg "bandwidthPriority"
         |         | yes       | torrent-set          | new arg "honorsSessionLimits"
         |         | yes       | torrent-set          | new arg "seedRatioLimit" 
         |         | yes       | torrent-set          | new arg "seedRatioLimited" 
         |         |        NO | torrent-set          | renamed "speed-limit-down" to "downloadLimit" 
         |         |        NO | torrent-set          | renamed "speed-limit-down-enabled" to "downloadLimited" 
         |         |        NO | torrent-set          | renamed "speed-limit-up" to "uploadLimit" 
         |         |        NO | torrent-set          | renamed "speed-limit-up-enabled" to "uploadLimited" 
         |         |           |                      |
         |         | yes       | torrent-get          | new arg "bandwidthPriority"
         |         | yes       | torrent-get          | new arg "fileStats"
         |         | yes       | torrent-get          | new arg "honorsSessionLimits"
         |         | yes       | torrent-get          | new arg "percentDone"
         |         | yes       | torrent-get          | new arg "pieces"
         |         | yes       | torrent-get          | new arg "seedRatioLimit"
         |         | yes       | torrent-get          | new arg "seedRatioMode"
         |         | yes       | torrent-get          | new arg "torrentFile"
         |         | yes       | torrent-get          | new ids option "recently-active"
         |         |        NO | torrent-get          | removed arg "downloadLimitMode"
         |         |        NO | torrent-get          | removed arg "uploadLimitMode"
   ------+---------+-----------+----------------------+-------------------------------
   6     | 1.70    | yes       |                      | new "method torrent-set-location"
   ------+---------+-----------+----------------------+-------------------------------
   7     | 1.80    |        NO | torrent-get          | removed arg "announceResponse"
         |         |        NO | torrent-get          | removed arg "announceURL"
         |         |        NO | torrent-get          | removed arg "downloaders"
         |         |        NO | torrent-get          | removed arg "lastAnnounceTime"
         |         |        NO | torrent-get          | removed arg "lastScrapeTime"
         |         |        NO | torrent-get          | removed arg "leechers"
         |         |        NO | torrent-get          | removed arg "nextAnnounceTime"
         |         |        NO | torrent-get          | removed arg "nextScrapeTime"
         |         |        NO | torrent-get          | removed arg "scrapeResponse"
         |         |        NO | torrent-get          | removed arg "scrapeURL"
         |         |        NO | torrent-get          | removed arg "seeders"
         |         |        NO | torrent-get          | removed arg "timesCompleted"
         |         |        NO | torrent-get          | removed arg "swarmSpeed"
         |         | yes       | torrent-get          | new arg "magnetLink"
         |         | yes       | torrent-get          | new arg "metadataPercentComplete"
         |         | yes       | torrent-get          | new arg "trackerStats"
         |         | yes       | session-set          | new arg "incomplete-dir"
         |         | yes       | session-set          | new arg "incomplete-dir-enabled"
   ------+---------+-----------+----------------------+-------------------------------
   8     | 1.90    | yes       | session-set          | new arg "rename-partial-files"
         |         | yes       | session-get          | new arg "rename-partial-files"
         |         | yes       | session-get          | new arg "config-dir"
         |         | yes       | torrent-add          | new arg "bandwidthPriority"
         |         | yes       | torrent-get          | new trackerStats arg "lastAnnounceTimedOut"
   ------+---------+-----------+----------------------+-------------------------------
   8     | 1.92    | yes       | torrent-get          | new trackerStats arg "lastScrapeTimedOut"
   ------+---------+-----------+----------------------+-------------------------------
   9     | 2.00    | yes       | session-set          | new arg "start-added-torrents"
         |         | yes       | session-set          | new arg "trash-original-torrent-files"
         |         | yes       | session-get          | new arg "start-added-torrents"
         |         | yes       | session-get          | new arg "trash-original-torrent-files"
         |         | yes       | torrent-get          | new arg "isFinished"
   ------+---------+-----------+----------------------+-------------------------------
   10    | 2.10    | yes       | session-get          | new arg "cache-size-mb"
         |         | yes       | torrent-set          | new arg "trackerAdd"
         |         | yes       | torrent-set          | new arg "trackerRemove"
         |         | yes       | torrent-set          | new arg "trackerReplace"
         |         | yes       | session-set          | new arg "idle-seeding-limit"
         |         | yes       | session-set          | new arg "idle-seeding-limit-enabled"
         |         | yes       | session-get          | new arg "units"
         |         | yes       | torrent-set          | new arg "seedIdleLimit"
         |         | yes       | torrent-set          | new arg "seedIdleMode"
   ------+---------+-----------+----------------------+-------------------------------
   11    | 2.12    | yes       | session-get          | new arg "blocklist-url"
         |         | yes       | session-set          | new arg "blocklist-url"
   ------+---------+-----------+----------------------+-------------------------------
   12    | 2.20    | yes       | session-get          | new arg "download-dir-free-space"
         |         | yes       | session-close        | new method
   ------+---------+-----------+----------------------+-------------------------------
   13    | 2.30    | yes       | session-get          | new arg "isUTP" to the "peers" list
         |         | yes       | torrent-add          | new arg "cookies"
         |         |        NO | torrent-get          | removed arg "peersKnown"
   ------+---------+-----------+--------------------------+-------------------------------
   14    | 2.40    |        NO | torrent-get          | values of "status" field changed
         |         | yes       | torrent-get          | new arg "queuePosition"
         |         | yes       | torrent-get          | new arg "isStalled"
         |         | yes       | torrent-get          | new arg "fromLpd" in peersFrom
         |         | yes       | torrent-set          | new arg "queuePosition"
         |         | yes       | session-set          | new arg "download-queue-size"
         |         | yes       | session-set          | new arg "download-queue-enabled"
         |         | yes       | session-set          | new arg "seed-queue-size"
         |         | yes       | session-set          | new arg "seed-queue-enabled"
         |         | yes       | session-set          | new arg "queue-stalled-enabled"
         |         | yes       | session-set          | new arg "queue-stalled-minutes"
         |         | yes       |                      | new method "queue-move-top"
         |         | yes       |                      | new method "queue-move-up"
         |         | yes       |                      | new method "queue-move-down"
         |         | yes       |                      | new method "queue-move-bottom"
         |         | yes       |                      | new method "torrent-start-now"
   ------+---------+-----------+--------------------------+-------------------------------
   15    | 2.80    | yes       | torrent-get          | new arg "etaIdle"
         |         | yes       | torrent-rename-path  | new method
         |         | yes       | free-space           | new method
         |         | yes       | torrent-add          | new return return arg "torrent-duplicate"

5.1.  Upcoming Breakage

   These features will be removed three months after 2.80's release:

   1. session-get's 'download-dir-free-space' argument will be removed.
      Its functionality has been superceded by the 'free-space' method.

   2. HTTP POSTs to http://server:port/transmission/upload will fail.
      This was an undocumented hack to allow web clients to add files without
      client-side access to the file. This functionality is superceded by
      using HTML5's FileReader object + the documented 'torrent-add' method.
