Start implementing the join room API

src/github.com/matrix-org/dendrite/clientapi/routing/routing.go

@@ -28,6 +28,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/writers"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
 	"github.com/prometheus/client_golang/prometheus"
 )
@@ -36,8 +37,13 @@ const pathPrefixR0 = "/_matrix/client/r0"
 
 // Setup registers HTTP handlers with the given ServeMux. It also supplies the given http.Client
 // to clients which need to make outbound HTTP requests.
-func Setup(servMux *http.ServeMux, httpClient *http.Client, cfg config.ClientAPI, producer *producers.RoomserverProducer,
-	queryAPI api.RoomserverQueryAPI, accountDB *accounts.Database, deviceDB *devices.Database) {
+func Setup(
+	servMux *http.ServeMux, httpClient *http.Client, cfg config.ClientAPI,
+	producer *producers.RoomserverProducer, queryAPI api.RoomserverQueryAPI,
+	accountDB *storage.AccountDatabase,
+	deviceDB *devices.Database,
+	federation *gomatrixserverlib.FederationClient,
+) {
 	apiMux := mux.NewRouter()
 	r0mux := apiMux.PathPrefix(pathPrefixR0).Subrouter()
 	r0mux.Handle("/createRoom",
@@ -45,6 +51,14 @@ func Setup(servMux *http.ServeMux, httpClient *http.Client, cfg config.ClientAPI
 			return writers.CreateRoom(req, device, cfg, producer)
 		}),
 	)
+	r0mux.Handle("/join/{roomIDOrAlias}",
+		makeAPI("join", func(req *http.Request) util.JSONResponse {
+			vars := mux.Vars(req)
+			return writers.JoinRoomByIDOrAlias(
+				req, vars["roomIDOrAlias"], cfg, federation, producer, queryAPI,
+			)
+		}),
+	)
 	r0mux.Handle("/rooms/{roomID}/send/{eventType}/{txnID}",
 		common.MakeAuthAPI("send_message", deviceDB, func(req *http.Request, device *authtypes.Device) util.JSONResponse {
 			vars := mux.Vars(req)

src/github.com/matrix-org/dendrite/clientapi/writers/joinroom.go

@@ -0,0 +1,223 @@
+// Copyright 2017 Vector Creations 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.
+
+package writers
+
+import (
+	"fmt"
+	"github.com/matrix-org/dendrite/clientapi/auth"
+	"github.com/matrix-org/dendrite/clientapi/config"
+	"github.com/matrix-org/dendrite/clientapi/httputil"
+	"github.com/matrix-org/dendrite/clientapi/jsonerror"
+	"github.com/matrix-org/dendrite/clientapi/producers"
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/gomatrix"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+	"net/http"
+	"strings"
+	"time"
+)
+
+// JoinRoomByIDOrAlias implements the "/join/{roomIDOrAlias}" API.
+// https://matrix.org/docs/spec/client_server/r0.2.0.html#post-matrix-client-r0-join-roomidoralias
+func JoinRoomByIDOrAlias(
+	req *http.Request,
+	roomIDOrAlias string,
+	cfg config.ClientAPI,
+	federation *gomatrixserverlib.FederationClient,
+	producer *producers.RoomserverProducer,
+	queryAPI api.RoomserverQueryAPI,
+) util.JSONResponse {
+	userID, resErr := auth.VerifyAccessToken(req)
+	if resErr != nil {
+		return *resErr
+	}
+	var content map[string]interface{} // must be a JSON object
+	if resErr := httputil.UnmarshalJSONRequest(req, &content); resErr != nil {
+		return *resErr
+	}
+
+	content["membership"] = "join"
+
+	r := joinRoomReq{req, content, userID, cfg, federation, producer, queryAPI}
+
+	if strings.HasPrefix(roomIDOrAlias, "!") {
+		return r.joinRoomByID()
+	}
+	if strings.HasPrefix(roomIDOrAlias, "#") {
+		return r.joinRoomByAlias(roomIDOrAlias)
+	}
+	return util.JSONResponse{
+		Code: 400,
+		JSON: jsonerror.BadJSON("Invalid first character for room ID or alias"),
+	}
+}
+
+type joinRoomReq struct {
+	req        *http.Request
+	content    map[string]interface{}
+	userID     string
+	cfg        config.ClientAPI
+	federation *gomatrixserverlib.FederationClient
+	producer   *producers.RoomserverProducer
+	queryAPI   api.RoomserverQueryAPI
+}
+
+// joinRoomByID joins a room by roomID
+func (r joinRoomReq) joinRoomByID() util.JSONResponse {
+	// TODO: Implement joining rooms by ID.
+	// A client should only join a room by roomID when it has an invite
+	// to the room. If the server is already in the room then we can
+	// lookup the invite and process the request as a normal state event.
+	// If the server is not in the room the we will need to look up the
+	// remote server the invite came from in order to request a join event
+	// from that server.
+	panic(fmt.Errorf("Joining rooms by ID is not implemented"))
+}
+
+// joinRoomByAlias joins a room using a room alias.
+func (r joinRoomReq) joinRoomByAlias(roomAlias string) util.JSONResponse {
+	domain, err := domainFromID(roomAlias)
+	if err != nil {
+		return util.JSONResponse{
+			Code: 400,
+			JSON: jsonerror.BadJSON("Room alias must be in the form '#localpart:domain'"),
+		}
+	}
+	if domain == r.cfg.ServerName {
+		// TODO: Implement joining local room aliases.
+		panic(fmt.Errorf("Joining local room aliases is not implemented"))
+	} else {
+		return r.joinRoomByRemoteAlias(domain, roomAlias)
+	}
+}
+
+func (r joinRoomReq) joinRoomByRemoteAlias(
+	domain gomatrixserverlib.ServerName, roomAlias string,
+) util.JSONResponse {
+	resp, err := r.federation.LookupRoomAlias(domain, roomAlias)
+	if err != nil {
+		switch x := err.(type) {
+		case gomatrix.HTTPError:
+			if x.Code == 404 {
+				return util.JSONResponse{
+					Code: 404,
+					JSON: jsonerror.NotFound("Room alias not found"),
+				}
+			}
+		}
+		return util.ErrorResponse(err)
+	}
+
+	return r.joinRoomUsingServers(resp.RoomID, resp.Servers)
+}
+
+func (r joinRoomReq) writeToBuilder(eb *gomatrixserverlib.EventBuilder, roomID string) {
+	eb.Type = "m.room.member"
+	eb.SetContent(r.content) // TODO: Set avatar_url / displayname
+	eb.SetUnsigned(struct{}{})
+	eb.Sender = r.userID
+	eb.StateKey = &r.userID
+	eb.RoomID = roomID
+	eb.Redacts = ""
+}
+
+func (r joinRoomReq) joinRoomUsingServers(
+	roomID string, servers []gomatrixserverlib.ServerName,
+) util.JSONResponse {
+	var eb gomatrixserverlib.EventBuilder
+	r.writeToBuilder(&eb, roomID)
+
+	needed, err := gomatrixserverlib.StateNeededForEventBuilder(&eb)
+	if err != nil {
+		return httputil.LogThenError(r.req, err)
+	}
+
+	// Ask the roomserver for information about this room
+	queryReq := api.QueryLatestEventsAndStateRequest{
+		RoomID:       roomID,
+		StateToFetch: needed.Tuples(),
+	}
+	var queryRes api.QueryLatestEventsAndStateResponse
+	if queryErr := r.queryAPI.QueryLatestEventsAndState(&queryReq, &queryRes); queryErr != nil {
+		return httputil.LogThenError(r.req, queryErr)
+	}
+
+	if queryRes.RoomExists {
+		// TODO: Implement joining rooms that already the server is already in.
+		// This should just fall through to the usual event sending code.
+		panic(fmt.Errorf("Joining rooms that the server already in is not implemented"))
+	}
+
+	var event gomatrixserverlib.Event
+	var respMakeJoin gomatrixserverlib.RespMakeJoin
+	//var respSendJoin gomatrixserverlib.RespSendJoin
+	for _, server := range servers {
+		respMakeJoin, err = r.federation.MakeJoin(server, roomID, r.userID)
+		if err != nil {
+			// TODO: Check if the user was not allowed to join the room.
+
+			// Try the next server in the list.
+			continue
+		}
+
+		// Set all the fields to be what they should be, this should be a no-op
+		// but it's possible that the remote server returned us something "odd"
+		r.writeToBuilder(&respMakeJoin.JoinEvent, roomID)
+
+		now := time.Now()
+		eventID := fmt.Sprintf("$%s:%s", util.RandomString(16), r.cfg.ServerName)
+		if event, err = respMakeJoin.JoinEvent.Build(
+			eventID, now, r.cfg.ServerName, r.cfg.KeyID, r.cfg.PrivateKey,
+		); err != nil {
+			return util.ErrorResponse(err)
+		}
+
+		_, err = r.federation.SendJoin(server, event)
+		if err != nil {
+			// Try the next server in the list.
+			continue
+		}
+
+		// TODO: validate the state response.
+		// TODO: check that the join event passes auth against the state response.
+		// TODO: send the state and the join event to the room server.
+	}
+
+	if err != nil {
+		return util.ErrorResponse(err)
+	}
+
+	return util.JSONResponse{
+		Code: 404,
+		JSON: jsonerror.NotFound("No candidate servers found for room"),
+	}
+}
+
+// domainFromID returns everything after the first ":" character to extract
+// the domain part of a matrix ID.
+// TODO: duplicated from gomatrixserverlib.
+func domainFromID(id string) (gomatrixserverlib.ServerName, error) {
+	// IDs have the format: SIGIL LOCALPART ":" DOMAIN
+	// Split on the first ":" character since the domain can contain ":"
+	// characters.
+	parts := strings.SplitN(id, ":", 2)
+	if len(parts) != 2 {
+		// The ID must have a ":" character.
+		return "", fmt.Errorf("invalid ID: %q", id)
+	}
+	// Return everything after the first ":" character.
+	return gomatrixserverlib.ServerName(parts[1]), nil
+}

src/github.com/matrix-org/dendrite/cmd/dendrite-client-api-server/main.go

@@ -26,6 +26,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/routing"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/roomserver/api"
+
 	"github.com/matrix-org/gomatrixserverlib"
 
 	log "github.com/Sirupsen/logrus"
@@ -81,6 +82,8 @@ func main() {
 		log.Panicf("Failed to setup kafka producers(%s): %s", cfg.KafkaProducerURIs, err)
 	}
 
+	federation := gomatrixserverlib.NewFederationClient(cfg.ServerName, cfg.KeyID, cfg.PrivateKey)
+
 	queryAPI := api.NewRoomserverQueryAPIHTTP(cfg.RoomserverURL, nil)
 	accountDB, err := accounts.NewDatabase(accountDataSource, serverName)
 	if err != nil {
@@ -91,6 +94,6 @@ func main() {
 		log.Panicf("Failed to setup device database(%s): %s", accountDataSource, err.Error())
 	}
 
-	routing.Setup(http.DefaultServeMux, http.DefaultClient, cfg, roomserverProducer, queryAPI, accountDB, deviceDB)
+	routing.Setup(http.DefaultServeMux, http.DefaultClient, cfg, roomserverProducer, queryAPI, accountDB, deviceDB, federation)
 	log.Fatal(http.ListenAndServe(bindAddr, nil))
 }