--- layout: post title: Client Server API categories: guides --- .. TODO kegan Room config (specifically: message history, public rooms). How to use the client-server API ================================ .. NOTE:: The git version of this document is ``{% project_version %}`` This guide focuses on how the client-server APIs *provided by the reference homeserver* can be used. Since this is specific to a homeserver implementation, there may be variations in relation to registering/logging in which are not covered in extensive detail in this guide. If you haven't already, get a homeserver up and running on ``https://localhost:8448``. Accounts ======== Before you can send and receive messages, you must **register** for an account. If you already have an account, you must **login** into it. .. NOTE:: `Try out the fiddle`__ .. __: http://jsfiddle.net/gh/get/jquery/1.8.3/matrix-org/matrix-doc/tree/master/supporting-docs/howtos/jsfiddles/register_login Registration ------------ The aim of registration is to get a user ID and access token which you will need when accessing other APIs:: curl -XPOST -d '{"username":"example", "password":"wordpass", "auth": {"type":"m.login.dummy"}}' "https://localhost:8448/_matrix/client/r0/register" { "access_token": "QGV4YW1wbGU6bG9jYWxob3N0.AqdSzFmFYrLrTmteXc", "home_server": "localhost", "user_id": "@example:localhost" } NB: If a ``user`` is not specified, one will be randomly generated for you. If you do not specify a ``password``, you will be unable to login to the account if you forget the ``access_token``. Implementation note: The matrix specification does not enforce how users register with a server. It just specifies the URL path and absolute minimum keys. The reference homeserver uses a username/password to authenticate user, but other homeservers may use different methods. This is why you need to specify the ``type`` of method. Login ----- The aim when logging in is to get an access token for your existing user ID:: curl -XGET "https://localhost:8448/_matrix/client/r0/login" { "flows": [ { "type": "m.login.password" } ] } curl -XPOST -d '{"type":"m.login.password", "user":"example", "password":"wordpass"}' "https://localhost:8448/_matrix/client/r0/login" { "access_token": "QGV4YW1wbGU6bG9jYWxob3N0.vRDLTgxefmKWQEtgGd", "home_server": "localhost", "user_id": "@example:localhost" } Implementation note: Different homeservers may implement different methods for logging in to an existing account. In order to check that you know how to login to this homeserver, you must perform a ``GET`` first and make sure you recognise the login type. If you do not know how to login, you can ``GET /login/fallback`` which will return a basic webpage which you can use to login. The reference homeserver implementation support username/password login, but other homeservers may support different login methods (e.g. OAuth2). Communicating ============= In order to communicate with another user, you must **create a room** with that user and **send a message** to that room. .. NOTE:: `Try out the fiddle`__ .. __: http://jsfiddle.net/gh/get/jquery/1.8.3/matrix-org/matrix-doc/tree/master/supporting-docs/howtos/jsfiddles/create_room_send_msg Creating a room --------------- If you want to send a message to someone, you have to be in a room with them. To create a room:: curl -XPOST -d '{"room_alias_name":"tutorial"}' "https://localhost:8448/_matrix/client/r0/createRoom?access_token=YOUR_ACCESS_TOKEN" { "room_alias": "#tutorial:localhost", "room_id": "!asfLdzLnOdGRkdPZWu:localhost" } The "room alias" is a human-readable string which can be shared with other users so they can join a room, rather than the room ID which is a randomly generated string. You can have multiple room aliases per room. .. TODO(kegan) How to add/remove aliases from an existing room. Sending messages ---------------- You can now send messages to this room:: curl -XPOST -d '{"msgtype":"m.text", "body":"hello"}' "https://localhost:8448/_matrix/client/r0/rooms/%21asfLdzLnOdGRkdPZWu:localhost/send/m.room.message?access_token=YOUR_ACCESS_TOKEN" { "event_id": "YUwRidLecu" } The event ID returned is a unique ID which identifies this message. NB: There are no limitations to the types of messages which can be exchanged. The only requirement is that ``"msgtype"`` is specified. The Matrix specification outlines the following standard types: ``m.text``, ``m.image``, ``m.audio``, ``m.video``, ``m.location``, ``m.emote``. See the specification for more information on these types. Users and rooms =============== Each room can be configured to allow or disallow certain rules. In particular, these rules may specify if you require an **invitation** from someone already in the room in order to **join the room**. In addition, you may also be able to join a room **via a room alias** if one was set up. .. NOTE:: `Try out the fiddle`__ .. __: http://jsfiddle.net/gh/get/jquery/1.8.3/matrix-org/matrix-doc/tree/master/supporting-docs/howtos/jsfiddles/room_memberships Inviting a user to a room ------------------------- You can directly invite a user to a room like so:: curl -XPOST -d '{"user_id":"@myfriend:localhost"}' "https://localhost:8448/_matrix/client/r0/rooms/%21asfLdzLnOdGRkdPZWu:localhost/invite?access_token=YOUR_ACCESS_TOKEN" This informs ``@myfriend:localhost`` of the room ID ``!CvcvRuDYDzTOzfKKgh:localhost`` and allows them to join the room. Joining a room via an invite ---------------------------- If you receive an invite, you can join the room:: curl -XPOST -d '{}' "https://localhost:8448/_matrix/client/r0/rooms/%21asfLdzLnOdGRkdPZWu:localhost/join?access_token=YOUR_ACCESS_TOKEN" NB: Only the person invited (``@myfriend:localhost``) can change the membership state to ``"join"``. Repeatedly joining a room does nothing. Joining a room via an alias --------------------------- Alternatively, if you know the room alias for this room and the room config allows it, you can directly join a room via the alias:: curl -XPOST -d '{}' "https://localhost:8448/_matrix/client/r0/join/%21asfLdzLnOdGRkdPZWu:localhost?access_token=YOUR_ACCESS_TOKEN" { "room_id": "!CvcvRuDYDzTOzfKKgh:localhost" } You will need to use the room ID when sending messages, not the room alias. NB: If the room is configured to be an invite-only room, you will still require an invite in order to join the room even though you know the room alias. As a result, it is more common to see a room alias in relation to a public room, which do not require invitations. Getting events ============== An event is some interesting piece of data that a client may be interested in. It can be a message in a room, a room invite, etc. There are many different ways of getting events, depending on what the client already knows. .. NOTE:: `Try out the fiddle`__ .. __: http://jsfiddle.net/gh/get/jquery/1.8.3/matrix-org/matrix-doc/tree/master/supporting-docs/howtos/jsfiddles/event_stream Getting all state ----------------- If the client doesn't know any information on the rooms the user is invited/joined on, they can get all the user's state for all rooms:: curl -XGET "https://localhost:8448/_matrix/client/r0/sync?access_token=YOUR_ACCESS_TOKEN" { "account_data": { "events": [ { ... } ] }, "next_batch": "s9_3_0_1_1_1", "presence": { "events": [ { "content": { "currently_active": true, "last_active_ago": 19, "presence": "online" }, "sender": "@example:localhost", "type": "m.presence" } ] }, "rooms": { "invite": {}, "join": { "!asfLdzLnOdGRkdPZWu:localhost": { "account_data": { "events": [] }, "ephemeral": { "events": [] }, "state": { "events": [] }, "timeline": { "events": [ { "content": { "creator": "@example:localhost" }, "event_id": "$14606534990LhqHt:localhost", "origin_server_ts": 1460653499699, "sender": "@example:localhost", "state_key": "", "type": "m.room.create", "unsigned": { "age": 239192 } }, { "content": { "avatar_url": null, "displayname": null, "membership": "join" }, "event_id": "$14606534991nsZKk:localhost", "membership": "join", "origin_server_ts": 1460653499727, "sender": "@example:localhost", "state_key": "@example:localhost", "type": "m.room.member", "unsigned": { "age": 239164 } }, ... ], "limited": false, "prev_batch": "s9_3_0_1_1_1" }, "unread_notifications": {} } }, "leave": {} } } This returns all the room information the user is invited/joined on, as well as all of the presences relevant for these rooms. This can be a LOT of data. You may just want the most recent event for each room. This can be achieved by applying a filter that asks for a limit of 1 timeline event per room:: curl --globoff -XGET "https://localhost:8448/_matrix/client/r0/sync?filter={'room':{'timeline':{'limit':1}}}&access_token=YOUR_ACCESS_TOKEN" { ... "rooms": { "invite": {}, "join": { "!asfLdzLnOdGRkdPZWu:localhost": { ... "timeline": { "events": [ { "content": { "body": "hello", "msgtype": "m.text" }, "event_id": "$14606535757KCGXo:localhost", "origin_server_ts": 1460653575105, "sender": "@example:localhost", "type": "m.room.message", "unsigned": { "age": 800348 } } ], "limited": true, "prev_batch": "t8-8_7_0_1_1_1" }, "unread_notifications": {} } }, "leave": {} } } (additionally we have to ask ``curl`` not to try to interpret any ``{}`` characters in the URL, which is what the ``--globoff`` option is for) Getting live state ------------------ In the response to this ``sync`` request the server includes a token that can be used to obtain updates since this point under the object key ``next_batch``. To use this token, specify its value as the ``since`` parameter to another ``/sync`` request.:: curl -XGET "https://localhost:8448/_matrix/client/r0/sync?since=s9_7_0_1_1_1&access_token=YOUR_ACCESS_TOKEN" { "account_data": { "events": [] }, "next_batch": "s9_9_0_1_1_1", "presence": { "events": [ { "content": { "currently_active": true, "last_active_ago": 12, "presence": "online" }, "sender": "@example:localhost", "type": "m.presence" } ] }, "rooms": { "invite": {}, "join": {}, "leave": {} } } By default this request will not wait in the server, always returning a value even if nothing interesting happened. However, by applying the ``timeout`` query parameter, which gives a duration in miliseconds, we can ask the server to wait for up to that amount of time before it returns. If no interesting events have happened since then, the response will be relatively empty.:: curl -XGET "https://localhost:8448/_matrix/client/r0/sync?since=s9_13_0_1_1_1&access_token=YOUR_ACCESS_TOKEN" { "account_data": { "events": [] }, "next_batch": "s9_13_0_1_1_1", "presence": { "events": [] }, "rooms": { "invite": {}, "join": {}, "leave": {} } } Example application ------------------- The following example demonstrates registration and login, live event streaming, creating and joining rooms, sending messages, getting member lists and getting historical messages for a room. This covers most functionality of a messaging application. .. NOTE:: `Try out the fiddle`__ .. __: http://jsfiddle.net/gh/get/jquery/1.8.3/matrix-org/matrix-doc/tree/master/supporting-docs/howtos/jsfiddles/example_app