# Copyright 2018-2020 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
openapi: 3.1.0
info:
  title: Matrix Federation Events API
  version: 1.0.0
paths:
  "/state/{roomId}":
    get:
      summary: Get all the state of a given room
      description: Retrieves a snapshot of a room's state at a given event.
      operationId: getRoomState
      security:
        - signedRequest: []
      parameters:
        - in: path
          name: roomId
          description: The room ID to get state for.
          required: true
          example: "!abc123:matrix.org"
          schema:
            type: string
        - in: query
          name: event_id
          description: An event ID in the room to retrieve the state at.
          required: true
          example: $helloworld:matrix.org
          schema:
            type: string
      responses:
        "200":
          description: |-
            The fully resolved state for the room, prior to considering any state
            changes induced by the requested event. Includes the authorization
            chain for the events.
          content:
            application/json:
              schema:
                type: object
                properties:
                  auth_chain:
                    type: array
                    description: |-
                      The full set of authorization events that make up the state
                      of the room, and their authorization events, recursively. Note that
                      events have a different format depending on the room version -
                      check the [room version specification](/rooms) for precise event formats.
                    items:
                      type: object
                      title: PDU
                      description: |-
                        The [PDUs](/server-server-api/#pdus) contained in the auth chain. The event format
                        varies depending on the room version - check the [room version specification](/rooms)
                        for precise event formats.
                      properties: {}
                      example:
                        $ref: examples/minimal_pdu.json
                  pdus:
                    type: array
                    description: |-
                      The fully resolved state of the room at the given event. Note that
                      events have a different format depending on the room version -
                      check the [room version specification](/rooms) for precise event formats.
                    items:
                      type: object
                      title: PDU
                      description: |-
                        The [PDUs](/server-server-api/#pdus) for the fully resolved state of the room. The event format
                        varies depending on the room version - check the [room version specification](/rooms)
                        for precise event formats.
                      properties: {}
                      example:
                        $ref: examples/minimal_pdu.json
                required:
                  - auth_chain
                  - pdus
  "/state_ids/{roomId}":
    get:
      summary: Get all the state event IDs of a given room
      description: |-
        Retrieves a snapshot of a room's state at a given event, in the form of
        event IDs. This performs the same function as calling `/state/{roomId}`,
        however this returns just the event IDs rather than the full events.
      operationId: getRoomStateIds
      security:
        - signedRequest: []
      parameters:
        - in: path
          name: roomId
          description: The room ID to get state for.
          required: true
          example: "!abc123:matrix.org"
          schema:
            type: string
        - in: query
          name: event_id
          description: An event ID in the room to retrieve the state at.
          required: true
          example: $helloworld:matrix.org
          schema:
            type: string
      responses:
        "200":
          description: |-
            The fully resolved state for the room, prior to considering any state
            changes induced by the requested event. Includes the authorization
            chain for the events.
          content:
            application/json:
              schema:
                type: object
                properties:
                  auth_chain_ids:
                    type: array
                    description: |-
                      The full set of authorization events that make up the state
                      of the room, and their authorization events, recursively.
                    items:
                      type: string
                    example:
                      - $an_event:example.org
                  pdu_ids:
                    type: array
                    description: The fully resolved state of the room at the given event.
                    items:
                      type: string
                    example:
                      - $an_event:example.org
                required:
                  - auth_chain_ids
                  - pdu_ids
        "403":
          description: |-
            The host is not in the room or the host is banned from the room via its ACL.
          content:
            application/json:
              schema:
                $ref: ../client-server/definitions/errors/error.yaml
              examples:
                response:
                  value: {
                    "errcode": "M_FORBIDDEN",
                    "error": "You do not have permission to access the state at the requested event."
                  }
        "404":
          description: |-
            The given `event_id` was not found or the server doesn't know about the state at
            that event to return anything useful.
          content:
            application/json:
              schema:
                $ref: ../client-server/definitions/errors/error.yaml
              examples:
                response:
                  value: {
                    "errcode": "M_NOT_FOUND",
                    "error": "Could not find event $Rqnc-F-dvnEYJTyHq_iKxU2bZ1CI92-kuZq3a5lr5Zg"
                  }
  "/event/{eventId}":
    get:
      summary: Get a single event
      description: Retrieves a single event.
      operationId: getEvent
      security:
        - signedRequest: []
      parameters:
        - in: path
          name: eventId
          description: The event ID to get.
          required: true
          example: $abc123:matrix.org
          schema:
            type: string
      responses:
        "200":
          description: A transaction containing a single PDU which is the event requested.
          content:
            application/json:
              schema:
                $ref: definitions/single_pdu_transaction.yaml
  "/timestamp_to_event/{roomId}":
    get:
      summary: Get the closest event ID to the given timestamp
      x-addedInMatrixVersion: "1.6"
      description: |-
        Get the ID of the event closest to the given timestamp, in the
        direction specified by the `dir` parameter.

        This is primarily used when handling the corresponding
        [client-server endpoint](/client-server-api/#get_matrixclientv1roomsroomidtimestamp_to_event)
        when the server does not have all of the room history, and does not
        have an event suitably close to the requested timestamp.

        The heuristics for deciding when to ask another homeserver for a closer
        event if your homeserver doesn't have something close, are left up to
        the homeserver implementation, although the heuristics will probably be
        based on whether the closest event is a forward/backward extremity
        indicating it's next to a gap of events which are potentially closer.

        A good heuristic for which servers to try first is to sort by servers
        that have been in the room the longest because they're most likely to
        have anything we ask about.

        After the local homeserver receives the response, it should determine,
        using the `origin_server_ts` property, whether the returned event is
        closer to the requested timestamp than the closest event that it could
        find locally.  If so, it should try to backfill this event via the
        [`/event/{event_id}`](#get_matrixfederationv1eventeventid) endpoint so
        that it is available to for a client to query.
      operationId: getEventByTimestamp
      security:
        - accessToken: []
      parameters:
        - in: path
          name: roomId
          description: The ID of the room to search
          required: true
          example: "!636q39766251:matrix.org"
          schema:
            type: string
        - in: query
          name: ts
          description: |-
            The timestamp to search from, as given in milliseconds
            since the Unix epoch.
          required: true
          example: 1432684800000
          schema:
            type: integer
        - in: query
          name: dir
          description: The direction in which to search.  `f` for forwards, `b` for
            backwards.
          required: true
          example: f
          schema:
            type: string
            enum:
              - f
              - b
      responses:
        "200":
          description: An event was found matching the search parameters.
          content:
            application/json:
              schema:
                type: object
                properties:
                  event_id:
                    type: string
                    description: The ID of the event found
                  origin_server_ts:
                    type: integer
                    description: The event's timestamp, in milliseconds since the Unix epoch.
                required:
                  - event_id
                  - origin_server_ts
              examples:
                response:
                  value: {
                    "event_id": "$143273582443PhrSn:example.org",
                    "origin_server_ts": 1432735824653
                  }
        "404":
          description: No event was found.
          content:
            application/json:
              schema:
                $ref: ../client-server/definitions/errors/error.yaml
              examples:
                response:
                  value: {
                    "errcode": "M_NOT_FOUND",
                    "error": "Unable to find event from 1432684800000 in forward direction"
                  }
servers:
  - url: "{protocol}://{hostname}{basePath}"
    variables:
      protocol:
        enum:
          - http
          - https
        default: https
      hostname:
        default: localhost:8448
      basePath:
        default: /_matrix/federation/v1
components:
  securitySchemes:
    signedRequest:
      $ref: definitions/security.yaml#/signedRequest
