Implement GET /rooms/{roomAlias} (#494)

* Query whether a room alias exists on app services

Signed-off-by: Andrew Morgan <andrewm@matrix.org>

* URL encode room alias before sending to AS

* Add /room/ to path

* Query AS /alias/ API at a lower level

* Don't verify self-signed AS certificates

* Don't skip cert validation on appservices, fix logging

* Separate req.WithContext

* Linting

* Do not warn when an AS room alias does not exist

src/github.com/matrix-org/dendrite/appservice/api/query.go

@@ -18,16 +18,41 @@
 package api
 
 import (
+	"context"
 	"net/http"
+
+	commonHTTP "github.com/matrix-org/dendrite/common/http"
+	opentracing "github.com/opentracing/opentracing-go"
 )
 
+// RoomAliasExistsRequest is a request to an application service
+// about whether a room alias exists
+type RoomAliasExistsRequest struct {
+	// Alias we want to lookup
+	Alias string `json:"alias"`
+}
+
+// RoomAliasExistsResponse is a response from an application service
+// about whether a room alias exists
+type RoomAliasExistsResponse struct {
+	AliasExists bool `json:"exists"`
+}
+
 // AppServiceQueryAPI is used to query user and room alias data from application
 // services
 type AppServiceQueryAPI interface {
-	// TODO: Check whether a room alias exists within any application service namespaces
+	// Check whether a room alias exists within any application service namespaces
+	RoomAliasExists(
+		ctx context.Context,
+		req *RoomAliasExistsRequest,
+		response *RoomAliasExistsResponse,
+	) error
 	// TODO: QueryUserIDExists
 }
 
+// AppServiceRoomAliasExistsPath is the HTTP path for the RoomAliasExists API
+const AppServiceRoomAliasExistsPath = "/api/appservice/RoomAliasExists"
+
 // httpAppServiceQueryAPI contains the URL to an appservice query API and a
 // reference to a httpClient used to reach it
 type httpAppServiceQueryAPI struct {
@@ -47,3 +72,16 @@ func NewAppServiceQueryAPIHTTP(
 	}
 	return &httpAppServiceQueryAPI{appserviceURL, httpClient}
 }
+
+// RoomAliasExists implements AppServiceQueryAPI
+func (h *httpAppServiceQueryAPI) RoomAliasExists(
+	ctx context.Context,
+	request *RoomAliasExistsRequest,
+	response *RoomAliasExistsResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "appserviceRoomAliasExists")
+	defer span.Finish()
+
+	apiURL := h.appserviceURL + AppServiceRoomAliasExistsPath
+	return commonHTTP.PostJSON(ctx, span, h.httpClient, apiURL, request, response)
+}

src/github.com/matrix-org/dendrite/appservice/appservice.go

@@ -74,14 +74,12 @@ func SetupAppServiceAPIComponent(
 		}
 	}
 
-	// Create a HTTP client that this component will use for all outbound and
-	// inbound requests (inbound only for the internal API)
-	httpClient := &http.Client{
-		Timeout: time.Second * 30,
-	}
-
+	// Create appserivce query API with an HTTP client that will be used for all
+	// outbound and inbound requests (inbound only for the internal API)
 	appserviceQueryAPI := query.AppServiceQueryAPI{
-		HTTPClient: httpClient,
+		HTTPClient: &http.Client{
+			Timeout: time.Second * 30,
+		},
 		Cfg: base.Cfg,
 	}
 

src/github.com/matrix-org/dendrite/appservice/consumers/roomserver.go

@@ -185,6 +185,7 @@ func (s *OutputRoomEventConsumer) appserviceIsInterestedInEvent(ctx context.Cont
 		return false
 	}
 
+	// Check Room ID and Sender of the event
 	if appservice.IsInterestedInUserID(event.Sender()) ||
 		appservice.IsInterestedInRoomID(event.RoomID()) {
 		return true

src/github.com/matrix-org/dendrite/appservice/query/query.go

@@ -17,18 +17,118 @@
 package query
 
 import (
+	"context"
+	"encoding/json"
 	"net/http"
+	"net/url"
+	"time"
 
+	"github.com/matrix-org/dendrite/appservice/api"
+	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/common/config"
+	"github.com/matrix-org/util"
+	opentracing "github.com/opentracing/opentracing-go"
+	log "github.com/sirupsen/logrus"
 )
 
+const roomAliasExistsPath = "/rooms/"
+
 // AppServiceQueryAPI is an implementation of api.AppServiceQueryAPI
 type AppServiceQueryAPI struct {
 	HTTPClient *http.Client
 	Cfg        *config.Dendrite
 }
 
+// RoomAliasExists performs a request to '/room/{roomAlias}' on all known
+// handling application services until one admits to owning the room
+func (a *AppServiceQueryAPI) RoomAliasExists(
+	ctx context.Context,
+	request *api.RoomAliasExistsRequest,
+	response *api.RoomAliasExistsResponse,
+) error {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "ApplicationServiceRoomAlias")
+	defer span.Finish()
+
+	// Create an HTTP client if one does not already exist
+	if a.HTTPClient == nil {
+		a.HTTPClient = makeHTTPClient()
+	}
+
+	// Determine which application service should handle this request
+	for _, appservice := range a.Cfg.Derived.ApplicationServices {
+		if appservice.URL != "" && appservice.IsInterestedInRoomAlias(request.Alias) {
+			// The full path to the rooms API, includes hs token
+			URL, err := url.Parse(appservice.URL + roomAliasExistsPath)
+			URL.Path += request.Alias
+			apiURL := URL.String() + "?access_token=" + appservice.HSToken
+
+			// Send a request to each application service. If one responds that it has
+			// created the room, immediately return.
+			req, err := http.NewRequest(http.MethodGet, apiURL, nil)
+			if err != nil {
+				return err
+			}
+			req = req.WithContext(ctx)
+
+			resp, err := a.HTTPClient.Do(req)
+			if resp != nil {
+				defer func() {
+					err = resp.Body.Close()
+					if err != nil {
+						log.WithFields(log.Fields{
+							"appservice_id": appservice.ID,
+							"status_code":   resp.StatusCode,
+						}).WithError(err).Error("Unable to close application service response body")
+					}
+				}()
+			}
+			if err != nil {
+				log.WithError(err).Errorf("Issue querying room alias on application service %s", appservice.ID)
+				return err
+			}
+			switch resp.StatusCode {
+			case http.StatusOK:
+				// OK received from appservice. Room exists
+				response.AliasExists = true
+				return nil
+			case http.StatusNotFound:
+				// Room does not exist
+			default:
+				// Application service reported an error. Warn
+				log.WithFields(log.Fields{
+					"appservice_id": appservice.ID,
+					"status_code":   resp.StatusCode,
+				}).Warn("Application service responded with non-OK status code")
+			}
+		}
+	}
+
+	response.AliasExists = false
+	return nil
+}
+
+// makeHTTPClient creates an HTTP client with certain options that will be used for all query requests to application services
+func makeHTTPClient() *http.Client {
+	return &http.Client{
+		Timeout: time.Second * 30,
+	}
+}
+
 // SetupHTTP adds the AppServiceQueryPAI handlers to the http.ServeMux. This
 // handles and muxes incoming api requests the to internal AppServiceQueryAPI.
 func (a *AppServiceQueryAPI) SetupHTTP(servMux *http.ServeMux) {
+	servMux.Handle(
+		api.AppServiceRoomAliasExistsPath,
+		common.MakeInternalAPI("appserviceRoomAliasExists", func(req *http.Request) util.JSONResponse {
+			var request api.RoomAliasExistsRequest
+			var response api.RoomAliasExistsResponse
+			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
+				return util.ErrorResponse(err)
+			}
+			if err := a.RoomAliasExists(req.Context(), &request, &response); err != nil {
+				return util.ErrorResponse(err)
+			}
+			return util.JSONResponse{Code: http.StatusOK, JSON: &response}
+		}),
+	)
 }

src/github.com/matrix-org/dendrite/appservice/workers/transaction_scheduler.go

@@ -17,7 +17,6 @@ package workers
 import (
 	"bytes"
 	"context"
-	"crypto/tls"
 	"encoding/json"
 	"fmt"
 	"math"
@@ -68,12 +67,6 @@ func worker(db *storage.Database, ws types.ApplicationServiceWorkerState) {
 	// Create a HTTP client for sending requests to app services
 	client := &http.Client{
 		Timeout: transactionTimeout,
-		// TODO: Verify certificates
-		Transport: &http.Transport{
-			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: true, // nolint: gas
-			},
-		},
 	}
 
 	// Initial check for any leftover events to send from last time

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

@@ -15,13 +15,14 @@
 package routing
 
 import (
+	"fmt"
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
 	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/common/config"
-	"github.com/matrix-org/dendrite/roomserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
@@ -33,7 +34,7 @@ func DirectoryRoom(
 	roomAlias string,
 	federation *gomatrixserverlib.FederationClient,
 	cfg *config.Dendrite,
-	aliasAPI api.RoomserverAliasAPI,
+	rsAPI roomserverAPI.RoomserverAliasAPI,
 ) util.JSONResponse {
 	_, domain, err := gomatrixserverlib.SplitID('#', roomAlias)
 	if err != nil {
@@ -43,51 +44,48 @@ func DirectoryRoom(
 		}
 	}
 
-	var resp gomatrixserverlib.RespDirectory
-
 	if domain == cfg.Matrix.ServerName {
-		queryReq := api.GetRoomIDForAliasRequest{Alias: roomAlias}
-		var queryRes api.GetRoomIDForAliasResponse
-		if err = aliasAPI.GetRoomIDForAlias(req.Context(), &queryReq, &queryRes); err != nil {
+		// Query the roomserver API to check if the alias exists locally
+		queryReq := roomserverAPI.GetRoomIDForAliasRequest{Alias: roomAlias}
+		var queryRes roomserverAPI.GetRoomIDForAliasResponse
+		if err = rsAPI.GetRoomIDForAlias(req.Context(), &queryReq, &queryRes); err != nil {
 			return httputil.LogThenError(req, err)
 		}
 
+		// List any roomIDs found associated with this alias
 		if len(queryRes.RoomID) > 0 {
-			// TODO: List servers that are aware of this room alias
-			resp = gomatrixserverlib.RespDirectory{
-				RoomID:  queryRes.RoomID,
-				Servers: []gomatrixserverlib.ServerName{},
-			}
-		} else {
-			// If the response doesn't contain a non-empty string, return an error
 			return util.JSONResponse{
-				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound("Room alias " + roomAlias + " not found."),
+				Code: http.StatusOK,
+				JSON: queryRes,
 			}
 		}
 	} else {
-		resp, err = federation.LookupRoomAlias(req.Context(), domain, roomAlias)
+		// Query the federation for this room alias
+		resp, err := federation.LookupRoomAlias(req.Context(), domain, roomAlias)
 		if err != nil {
-			switch x := err.(type) {
+			switch err.(type) {
 			case gomatrix.HTTPError:
-				if x.Code == http.StatusNotFound {
-					return util.JSONResponse{
-						Code: http.StatusNotFound,
-						JSON: jsonerror.NotFound("Room alias not found"),
-					}
-				}
-			}
+			default:
 				// TODO: Return 502 if the remote server errored.
 				// TODO: Return 504 if the remote server timed out.
 				return httputil.LogThenError(req, err)
 			}
 		}
-
+		if len(resp.RoomID) > 0 {
 			return util.JSONResponse{
 				Code: http.StatusOK,
 				JSON: resp,
 			}
 		}
+	}
+
+	return util.JSONResponse{
+		Code: http.StatusNotFound,
+		JSON: jsonerror.NotFound(
+			fmt.Sprintf("Room alias %s not found", roomAlias),
+		),
+	}
+}
 
 // SetLocalAlias implements PUT /directory/room/{roomAlias}
 // TODO: Check if the user has the power level to set an alias
@@ -96,7 +94,7 @@ func SetLocalAlias(
 	device *authtypes.Device,
 	alias string,
 	cfg *config.Dendrite,
-	aliasAPI api.RoomserverAliasAPI,
+	aliasAPI roomserverAPI.RoomserverAliasAPI,
 ) util.JSONResponse {
 	_, domain, err := gomatrixserverlib.SplitID('#', alias)
 	if err != nil {
@@ -138,12 +136,12 @@ func SetLocalAlias(
 		return *resErr
 	}
 
-	queryReq := api.SetRoomAliasRequest{
+	queryReq := roomserverAPI.SetRoomAliasRequest{
 		UserID: device.UserID,
 		RoomID: r.RoomID,
 		Alias:  alias,
 	}
-	var queryRes api.SetRoomAliasResponse
+	var queryRes roomserverAPI.SetRoomAliasResponse
 	if err := aliasAPI.SetRoomAlias(req.Context(), &queryReq, &queryRes); err != nil {
 		return httputil.LogThenError(req, err)
 	}
@@ -167,13 +165,13 @@ func RemoveLocalAlias(
 	req *http.Request,
 	device *authtypes.Device,
 	alias string,
-	aliasAPI api.RoomserverAliasAPI,
+	aliasAPI roomserverAPI.RoomserverAliasAPI,
 ) util.JSONResponse {
-	queryReq := api.RemoveRoomAliasRequest{
+	queryReq := roomserverAPI.RemoveRoomAliasRequest{
 		Alias:  alias,
 		UserID: device.UserID,
 	}
-	var queryRes api.RemoveRoomAliasResponse
+	var queryRes roomserverAPI.RemoveRoomAliasResponse
 	if err := aliasAPI.RemoveRoomAlias(req.Context(), &queryReq, &queryRes); err != nil {
 		return httputil.LogThenError(req, err)
 	}

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

@@ -29,7 +29,7 @@ import (
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/common/config"
 	"github.com/matrix-org/dendrite/common/transactions"
-	"github.com/matrix-org/dendrite/roomserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
 )
@@ -42,8 +42,9 @@ const pathPrefixUnstable = "/_matrix/client/unstable"
 // to clients which need to make outbound HTTP requests.
 func Setup(
 	apiMux *mux.Router, cfg config.Dendrite,
-	producer *producers.RoomserverProducer, queryAPI api.RoomserverQueryAPI,
-	aliasAPI api.RoomserverAliasAPI,
+	producer *producers.RoomserverProducer,
+	queryAPI roomserverAPI.RoomserverQueryAPI,
+	aliasAPI roomserverAPI.RoomserverAliasAPI,
 	accountDB *accounts.Database,
 	deviceDB *devices.Database,
 	federation *gomatrixserverlib.FederationClient,
@@ -142,7 +143,7 @@ func Setup(
 	})).Methods(http.MethodGet, http.MethodOptions)
 
 	r0mux.Handle("/directory/room/{roomAlias}",
-		common.MakeAuthAPI("directory_room", authData, func(req *http.Request, device *authtypes.Device) util.JSONResponse {
+		common.MakeExternalAPI("directory_room", func(req *http.Request) util.JSONResponse {
 			vars := mux.Vars(req)
 			return DirectoryRoom(req, vars["roomAlias"], federation, &cfg, aliasAPI)
 		}),

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

@@ -19,6 +19,8 @@ import (
 	"github.com/matrix-org/dendrite/common/basecomponent"
 	"github.com/matrix-org/dendrite/common/keydb"
 	"github.com/matrix-org/dendrite/common/transactions"
+	"github.com/matrix-org/dendrite/typingserver"
+	"github.com/matrix-org/dendrite/typingserver/cache"
 )
 
 func main() {
@@ -34,12 +36,11 @@ func main() {
 	keyRing := keydb.CreateKeyRing(federation.Client, keyDB)
 
 	alias, input, query := base.CreateHTTPRoomserverAPIs()
-	typingInputAPI := base.CreateHTTPTypingServerAPIs()
-	cache := transactions.New()
+	typingInputAPI := typingserver.SetupTypingServerComponent(base, cache.NewTypingCache())
 
 	clientapi.SetupClientAPIComponent(
 		base, deviceDB, accountDB, federation, &keyRing,
-		alias, input, query, typingInputAPI, cache,
+		alias, input, query, typingInputAPI, transactions.New(),
 	)
 
 	base.SetupAndServeHTTP(string(base.Cfg.Listen.ClientAPI))

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

@@ -18,7 +18,6 @@ import (
 	"flag"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/appservice"
 	"github.com/matrix-org/dendrite/clientapi"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/common/basecomponent"
@@ -68,7 +67,6 @@ func main() {
 	mediaapi.SetupMediaAPIComponent(base, deviceDB)
 	publicroomsapi.SetupPublicRoomsAPIComponent(base, deviceDB)
 	syncapi.SetupSyncAPIComponent(base, deviceDB, accountDB, query)
-	appservice.SetupAppServiceAPIComponent(base, accountDB, deviceDB, federation, alias, query, transactions.New())
 
 	httpHandler := common.WrapHandlerInCORS(base.APIMux)
 

src/github.com/matrix-org/dendrite/federationapi/routing/query.go

@@ -21,7 +21,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/httputil"
 	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/common/config"
-	"github.com/matrix-org/dendrite/roomserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
@@ -32,7 +32,7 @@ func RoomAliasToID(
 	httpReq *http.Request,
 	federation *gomatrixserverlib.FederationClient,
 	cfg config.Dendrite,
-	aliasAPI api.RoomserverAliasAPI,
+	aliasAPI roomserverAPI.RoomserverAliasAPI,
 ) util.JSONResponse {
 	roomAlias := httpReq.FormValue("room_alias")
 	if roomAlias == "" {
@@ -52,8 +52,8 @@ func RoomAliasToID(
 	var resp gomatrixserverlib.RespDirectory
 
 	if domain == cfg.Matrix.ServerName {
-		queryReq := api.GetRoomIDForAliasRequest{Alias: roomAlias}
-		var queryRes api.GetRoomIDForAliasResponse
+		queryReq := roomserverAPI.GetRoomIDForAliasRequest{Alias: roomAlias}
+		var queryRes roomserverAPI.GetRoomIDForAliasResponse
 		if err = aliasAPI.GetRoomIDForAlias(httpReq.Context(), &queryReq, &queryRes); err != nil {
 			return httputil.LogThenError(httpReq, err)
 		}

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

@@ -23,7 +23,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/common/config"
-	"github.com/matrix-org/dendrite/roomserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
 )
@@ -37,8 +37,8 @@ const (
 func Setup(
 	apiMux *mux.Router,
 	cfg config.Dendrite,
-	query api.RoomserverQueryAPI,
-	aliasAPI api.RoomserverAliasAPI,
+	query roomserverAPI.RoomserverQueryAPI,
+	aliasAPI roomserverAPI.RoomserverAliasAPI,
 	producer *producers.RoomserverProducer,
 	keys gomatrixserverlib.KeyRing,
 	federation *gomatrixserverlib.FederationClient,

src/github.com/matrix-org/dendrite/roomserver/alias/alias.go

@@ -21,9 +21,10 @@ import (
 	"net/http"
 	"time"
 
+	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/common/config"
-	"github.com/matrix-org/dendrite/roomserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
 )
@@ -44,19 +45,20 @@ type RoomserverAliasAPIDatabase interface {
 	RemoveRoomAlias(ctx context.Context, alias string) error
 }
 
-// RoomserverAliasAPI is an implementation of api.RoomserverAliasAPI
+// RoomserverAliasAPI is an implementation of alias.RoomserverAliasAPI
 type RoomserverAliasAPI struct {
 	DB            RoomserverAliasAPIDatabase
 	Cfg           *config.Dendrite
-	InputAPI api.RoomserverInputAPI
-	QueryAPI api.RoomserverQueryAPI
+	InputAPI      roomserverAPI.RoomserverInputAPI
+	QueryAPI      roomserverAPI.RoomserverQueryAPI
+	AppserviceAPI appserviceAPI.AppServiceQueryAPI
 }
 
-// SetRoomAlias implements api.RoomserverAliasAPI
+// SetRoomAlias implements alias.RoomserverAliasAPI
 func (r *RoomserverAliasAPI) SetRoomAlias(
 	ctx context.Context,
-	request *api.SetRoomAliasRequest,
-	response *api.SetRoomAliasResponse,
+	request *roomserverAPI.SetRoomAliasRequest,
+	response *roomserverAPI.SetRoomAliasResponse,
 ) error {
 	// Check if the alias isn't already referring to a room
 	roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
@@ -82,11 +84,11 @@ func (r *RoomserverAliasAPI) SetRoomAlias(
 	return r.sendUpdatedAliasesEvent(context.TODO(), request.UserID, request.RoomID)
 }
 
-// GetRoomIDForAlias implements api.RoomserverAliasAPI
+// GetRoomIDForAlias implements alias.RoomserverAliasAPI
 func (r *RoomserverAliasAPI) GetRoomIDForAlias(
 	ctx context.Context,
-	request *api.GetRoomIDForAliasRequest,
-	response *api.GetRoomIDForAliasResponse,
+	request *roomserverAPI.GetRoomIDForAliasRequest,
+	response *roomserverAPI.GetRoomIDForAliasResponse,
 ) error {
 	// Look up the room ID in the database
 	roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
@@ -94,15 +96,23 @@ func (r *RoomserverAliasAPI) GetRoomIDForAlias(
 		return err
 	}
 
+	// No rooms found locally, try our application services by making a call to
+	// the appservice component
+	aliasReq := appserviceAPI.RoomAliasExistsRequest{Alias: request.Alias}
+	var aliasResp appserviceAPI.RoomAliasExistsResponse
+	if err = r.AppserviceAPI.RoomAliasExists(ctx, &aliasReq, &aliasResp); err != nil {
+		return err
+	}
+
 	response.RoomID = roomID
 	return nil
 }
 
-// GetAliasesForRoomID implements api.RoomserverAliasAPI
+// GetAliasesForRoomID implements alias.RoomserverAliasAPI
 func (r *RoomserverAliasAPI) GetAliasesForRoomID(
 	ctx context.Context,
-	request *api.GetAliasesForRoomIDRequest,
-	response *api.GetAliasesForRoomIDResponse,
+	request *roomserverAPI.GetAliasesForRoomIDRequest,
+	response *roomserverAPI.GetAliasesForRoomIDResponse,
 ) error {
 	// Look up the aliases in the database for the given RoomID
 	aliases, err := r.DB.GetAliasesForRoomID(ctx, request.RoomID)
@@ -114,11 +124,11 @@ func (r *RoomserverAliasAPI) GetAliasesForRoomID(
 	return nil
 }
 
-// RemoveRoomAlias implements api.RoomserverAliasAPI
+// RemoveRoomAlias implements alias.RoomserverAliasAPI
 func (r *RoomserverAliasAPI) RemoveRoomAlias(
 	ctx context.Context,
-	request *api.RemoveRoomAliasRequest,
-	response *api.RemoveRoomAliasResponse,
+	request *roomserverAPI.RemoveRoomAliasRequest,
+	response *roomserverAPI.RemoveRoomAliasResponse,
 ) error {
 	// Look up the room ID in the database
 	roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
@@ -177,11 +187,11 @@ func (r *RoomserverAliasAPI) sendUpdatedAliasesEvent(
 	if err != nil {
 		return err
 	}
-	req := api.QueryLatestEventsAndStateRequest{
+	req := roomserverAPI.QueryLatestEventsAndStateRequest{
 		RoomID:       roomID,
 		StateToFetch: eventsNeeded.Tuples(),
 	}
-	var res api.QueryLatestEventsAndStateResponse
+	var res roomserverAPI.QueryLatestEventsAndStateResponse
 	if err = r.QueryAPI.QueryLatestEventsAndState(ctx, &req, &res); err != nil {
 		return err
 	}
@@ -213,16 +223,16 @@ func (r *RoomserverAliasAPI) sendUpdatedAliasesEvent(
 	}
 
 	// Create the request
-	ire := api.InputRoomEvent{
-		Kind:         api.KindNew,
+	ire := roomserverAPI.InputRoomEvent{
+		Kind:         roomserverAPI.KindNew,
 		Event:        event,
 		AuthEventIDs: event.AuthEventIDs(),
 		SendAsServer: serverName,
 	}
-	inputReq := api.InputRoomEventsRequest{
-		InputRoomEvents: []api.InputRoomEvent{ire},
+	inputReq := roomserverAPI.InputRoomEventsRequest{
+		InputRoomEvents: []roomserverAPI.InputRoomEvent{ire},
 	}
-	var inputRes api.InputRoomEventsResponse
+	var inputRes roomserverAPI.InputRoomEventsResponse
 
 	// Send the request
 	return r.InputAPI.InputRoomEvents(ctx, &inputReq, &inputRes)
@@ -231,10 +241,10 @@ func (r *RoomserverAliasAPI) sendUpdatedAliasesEvent(
 // SetupHTTP adds the RoomserverAliasAPI handlers to the http.ServeMux.
 func (r *RoomserverAliasAPI) SetupHTTP(servMux *http.ServeMux) {
 	servMux.Handle(
-		api.RoomserverSetRoomAliasPath,
+		roomserverAPI.RoomserverSetRoomAliasPath,
 		common.MakeInternalAPI("setRoomAlias", func(req *http.Request) util.JSONResponse {
-			var request api.SetRoomAliasRequest
-			var response api.SetRoomAliasResponse
+			var request roomserverAPI.SetRoomAliasRequest
+			var response roomserverAPI.SetRoomAliasResponse
 			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
 				return util.ErrorResponse(err)
 			}
@@ -245,10 +255,10 @@ func (r *RoomserverAliasAPI) SetupHTTP(servMux *http.ServeMux) {
 		}),
 	)
 	servMux.Handle(
-		api.RoomserverGetRoomIDForAliasPath,
+		roomserverAPI.RoomserverGetRoomIDForAliasPath,
 		common.MakeInternalAPI("GetRoomIDForAlias", func(req *http.Request) util.JSONResponse {
-			var request api.GetRoomIDForAliasRequest
-			var response api.GetRoomIDForAliasResponse
+			var request roomserverAPI.GetRoomIDForAliasRequest
+			var response roomserverAPI.GetRoomIDForAliasResponse
 			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
 				return util.ErrorResponse(err)
 			}
@@ -259,10 +269,10 @@ func (r *RoomserverAliasAPI) SetupHTTP(servMux *http.ServeMux) {
 		}),
 	)
 	servMux.Handle(
-		api.RoomserverRemoveRoomAliasPath,
+		roomserverAPI.RoomserverRemoveRoomAliasPath,
 		common.MakeInternalAPI("removeRoomAlias", func(req *http.Request) util.JSONResponse {
-			var request api.RemoveRoomAliasRequest
-			var response api.RemoveRoomAliasResponse
+			var request roomserverAPI.RemoveRoomAliasRequest
+			var response roomserverAPI.RemoveRoomAliasResponse
 			if err := json.NewDecoder(req.Body).Decode(&request); err != nil {
 				return util.ErrorResponse(err)
 			}

src/github.com/matrix-org/dendrite/roomserver/roomserver.go

@@ -19,6 +19,7 @@ import (
 
 	"github.com/matrix-org/dendrite/roomserver/api"
 
+	asQuery "github.com/matrix-org/dendrite/appservice/query"
 	"github.com/matrix-org/dendrite/common/basecomponent"
 	"github.com/matrix-org/dendrite/roomserver/alias"
 	"github.com/matrix-org/dendrite/roomserver/input"
@@ -51,11 +52,14 @@ func SetupRoomServerComponent(
 
 	queryAPI.SetupHTTP(http.DefaultServeMux)
 
+	asAPI := asQuery.AppServiceQueryAPI{Cfg: base.Cfg}
+
 	aliasAPI := alias.RoomserverAliasAPI{
 		DB:            roomserverDB,
 		Cfg:           base.Cfg,
 		InputAPI:      &inputAPI,
 		QueryAPI:      &queryAPI,
+		AppserviceAPI: &asAPI,
 	}
 
 	aliasAPI.SetupHTTP(http.DefaultServeMux)