Merge pull request #54 from qua3k/context

Add `/context` API

client.go

@@ -1296,6 +1296,28 @@ func (cli *Client) Messages(roomID id.RoomID, from, to string, dir rune, limit i
 	return
 }
 
+// Context returns a number of events that happened just before and after the
+// specified event. It use pagination query parameters to paginate history in
+// the room.
+// See https://spec.matrix.org/v1.1/client-server-api/#get_matrixclientv3roomsroomidcontexteventid
+func (cli *Client) Context(roomID id.RoomID, eventID id.EventID, filter *Filter, limit int) (resp *RespContext, err error) {
+	query := map[string]string{}
+	if filter != nil {
+		filterJSON, err := json.Marshal(filter)
+		if err != nil {
+			return nil, err
+		}
+		query["filter"] = string(filterJSON)
+	}
+	if limit != 0 {
+		query["limit"] = strconv.Itoa(limit)
+	}
+
+	urlPath := cli.BuildURLWithQuery(URLPath{"rooms", roomID, "context", eventID}, query)
+	_, err = cli.MakeRequest("GET", urlPath, nil, &resp)
+	return
+}
+
 func (cli *Client) GetEvent(roomID id.RoomID, eventID id.EventID) (resp *event.Event, err error) {
 	urlPath := cli.BuildURL("rooms", roomID, "event", eventID)
 	_, err = cli.MakeRequest("GET", urlPath, nil, &resp)

responses.go

@@ -78,6 +78,16 @@ type RespMessages struct {
 	End   string         `json:"end"`
 }
 
+// RespContext is the JSON response for https://spec.matrix.org/v1.1/client-server-api/#get_matrixclientv3roomsroomidcontexteventid
+type RespContext struct {
+	End          string         `json:"end"`
+	Event        *event.Event   `json:"event"`
+	EventsAfter  []*event.Event `json:"events_after"`
+	EventsBefore []*event.Event `json:"events_before"`
+	Start        string         `json:"start"`
+	State        []*event.Event `json:"state"`
+}
+
 // RespSendEvent is the JSON response for http://matrix.org/docs/spec/client_server/r0.2.0.html#put-matrix-client-r0-rooms-roomid-send-eventtype-txnid
 type RespSendEvent struct {
 	EventID id.EventID `json:"event_id"`