Added .well-known/matrix/server endpoint (#1988)

* Added .well-known/matrix/server endpoint

Signed-off-by: Ryan Whittington <twentybitdev@gmail.com>

* Replaced tabs with spaces

Signed-off-by: Ryan Whittington <twentybitdev@gmail.com>

build/docker/config/dendrite-config.yaml

@@ -52,6 +52,10 @@ global:
   # considered valid by other homeservers.
   key_validity_period: 168h0m0s
 
+  # The server name to delegate server-server communications to, with optional port
+  # e.g. localhost:443
+  well_known_server_name: ""
+
   # Lists of domains that the server will trust as identity servers to verify third
   # party identifiers such as phone numbers and email addresses.
   trusted_third_party_id_servers:

build/gobind-pinecone/monolith.go

@@ -332,6 +332,7 @@ func (m *DendriteMonolith) Start() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

build/gobind-yggdrasil/monolith.go

@@ -156,6 +156,7 @@ func (m *DendriteMonolith) Start() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

cmd/dendrite-demo-libp2p/main.go

@@ -198,6 +198,7 @@ func main() {
 		base.Base.PublicClientAPIMux,
 		base.Base.PublicFederationAPIMux,
 		base.Base.PublicKeyAPIMux,
+		base.Base.PublicWellKnownAPIMux,
 		base.Base.PublicMediaAPIMux,
 		base.Base.SynapseAdminMux,
 	)

cmd/dendrite-demo-pinecone/main.go

@@ -210,6 +210,7 @@ func main() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

cmd/dendrite-demo-yggdrasil/main.go

@@ -145,6 +145,7 @@ func main() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

cmd/dendrite-monolith-server/main.go

@@ -161,6 +161,7 @@ func main() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

cmd/dendrite-polylith-multi/personalities/federationapi.go

@@ -30,7 +30,7 @@ func FederationAPI(base *setup.BaseDendrite, cfg *config.Dendrite) {
 	keyAPI := base.KeyServerHTTPClient()
 
 	federationapi.AddPublicRoutes(
-		base.PublicFederationAPIMux, base.PublicKeyAPIMux,
+		base.PublicFederationAPIMux, base.PublicKeyAPIMux, base.PublicWellKnownAPIMux,
 		&base.Cfg.FederationAPI, userAPI, federation, keyRing,
 		rsAPI, fsAPI, base.EDUServerClient(), keyAPI,
 		&base.Cfg.MSCs, nil,

cmd/dendritejs-pinecone/main.go

@@ -221,6 +221,7 @@ func startup() {
 		base.PublicClientAPIMux,
 		base.PublicFederationAPIMux,
 		base.PublicKeyAPIMux,
+		base.PublicWellKnownAPIMux,
 		base.PublicMediaAPIMux,
 		base.SynapseAdminMux,
 	)

dendrite-config.yaml

@@ -54,6 +54,10 @@ global:
   # considered valid by other homeservers.
   key_validity_period: 168h0m0s
 
+  # The server name to delegate server-server communications to, with optional port
+  # e.g. localhost:443
+  well_known_server_name: ""
+
   # Lists of domains that the server will trust as identity servers to verify third
   # party identifiers such as phone numbers and email addresses.
   trusted_third_party_id_servers:

federationapi/federationapi.go

@@ -30,7 +30,7 @@ import (
 
 // AddPublicRoutes sets up and registers HTTP handlers on the base API muxes for the FederationAPI component.
 func AddPublicRoutes(
-	fedRouter, keyRouter *mux.Router,
+	fedRouter, keyRouter, wellKnownRouter *mux.Router,
 	cfg *config.FederationAPI,
 	userAPI userapi.UserInternalAPI,
 	federation *gomatrixserverlib.FederationClient,
@@ -43,7 +43,7 @@ func AddPublicRoutes(
 	servers federationAPI.ServersInRoomProvider,
 ) {
 	routing.Setup(
-		fedRouter, keyRouter, cfg, rsAPI,
+		fedRouter, keyRouter, wellKnownRouter, cfg, rsAPI,
 		eduAPI, federationSenderAPI, keyRing,
 		federation, userAPI, keyAPI, mscCfg,
 		servers,

federationapi/federationapi_test.go

@@ -31,7 +31,7 @@ func TestRoomsV3URLEscapeDoNot404(t *testing.T) {
 	fsAPI := base.FederationSenderHTTPClient()
 	// TODO: This is pretty fragile, as if anything calls anything on these nils this test will break.
 	// Unfortunately, it makes little sense to instantiate these dependencies when we just want to test routing.
-	federationapi.AddPublicRoutes(base.PublicFederationAPIMux, base.PublicKeyAPIMux, &cfg.FederationAPI, nil, nil, keyRing, nil, fsAPI, nil, nil, &cfg.MSCs, nil)
+	federationapi.AddPublicRoutes(base.PublicFederationAPIMux, base.PublicKeyAPIMux, base.PublicWellKnownAPIMux, &cfg.FederationAPI, nil, nil, keyRing, nil, fsAPI, nil, nil, &cfg.MSCs, nil)
 	baseURL, cancel := test.ListenAndServe(t, base.PublicFederationAPIMux, true)
 	defer cancel()
 	serverName := gomatrixserverlib.ServerName(strings.TrimPrefix(baseURL, "https://"))

federationapi/routing/routing.go

@@ -30,6 +30,7 @@ import (
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
+	"github.com/sirupsen/logrus"
 )
 
 // Setup registers HTTP handlers with the given ServeMux.
@@ -41,7 +42,7 @@ import (
 // applied:
 // nolint: gocyclo
 func Setup(
-	fedMux, keyMux *mux.Router,
+	fedMux, keyMux, wkMux *mux.Router,
 	cfg *config.FederationAPI,
 	rsAPI roomserverAPI.RoomserverInternalAPI,
 	eduAPI eduserverAPI.EDUServerInputAPI,
@@ -85,6 +86,21 @@ func Setup(
 		return NotaryKeys(req, cfg, fsAPI, pkReq)
 	})
 
+	if cfg.Matrix.WellKnownServerName != "" {
+		logrus.Infof("Setting m.server as %s at /.well-known/matrix/server", cfg.Matrix.WellKnownServerName)
+		wkMux.Handle("/server", httputil.MakeExternalAPI("wellknown", func(req *http.Request) util.JSONResponse {
+			return util.JSONResponse{
+				Code: http.StatusOK,
+				JSON: struct {
+					ServerName string `json:"m.server"`
+				}{
+					ServerName: cfg.Matrix.WellKnownServerName,
+				},
+			}
+		}),
+		).Methods(http.MethodGet, http.MethodOptions)
+	}
+
 	// Ignore the {keyID} argument as we only have a single server key so we always
 	// return that key.
 	// Even if we had more than one server key, we would probably still ignore the

internal/httputil/paths.go

@@ -19,5 +19,6 @@ const (
 	PublicFederationPathPrefix = "/_matrix/federation/"
 	PublicKeyPathPrefix        = "/_matrix/key/"
 	PublicMediaPathPrefix      = "/_matrix/media/"
+	PublicWellKnownPrefix      = "/.well-known/matrix/"
 	InternalPathPrefix         = "/api/"
 )

setup/base.go

@@ -76,6 +76,7 @@ type BaseDendrite struct {
 	PublicFederationAPIMux *mux.Router
 	PublicKeyAPIMux        *mux.Router
 	PublicMediaAPIMux      *mux.Router
+	PublicWellKnownAPIMux  *mux.Router
 	InternalAPIMux         *mux.Router
 	SynapseAdminMux        *mux.Router
 	UseHTTPAPIs            bool
@@ -198,6 +199,7 @@ func NewBaseDendrite(cfg *config.Dendrite, componentName string, useHTTPAPIs boo
 		PublicFederationAPIMux: mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicFederationPathPrefix).Subrouter().UseEncodedPath(),
 		PublicKeyAPIMux:        mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicKeyPathPrefix).Subrouter().UseEncodedPath(),
 		PublicMediaAPIMux:      mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicMediaPathPrefix).Subrouter().UseEncodedPath(),
+		PublicWellKnownAPIMux:  mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicWellKnownPrefix).Subrouter().UseEncodedPath(),
 		InternalAPIMux:         mux.NewRouter().SkipClean(true).PathPrefix(httputil.InternalPathPrefix).Subrouter().UseEncodedPath(),
 		SynapseAdminMux:        mux.NewRouter().SkipClean(true).PathPrefix("/_synapse/").Subrouter().UseEncodedPath(),
 		apiHttpClient:          &apiClient,
@@ -394,6 +396,7 @@ func (b *BaseDendrite) SetupAndServeHTTP(
 	}
 	externalRouter.PathPrefix("/_synapse/").Handler(b.SynapseAdminMux)
 	externalRouter.PathPrefix(httputil.PublicMediaPathPrefix).Handler(b.PublicMediaAPIMux)
+	externalRouter.PathPrefix(httputil.PublicWellKnownPrefix).Handler(b.PublicWellKnownAPIMux)
 
 	if internalAddr != NoListener && internalAddr != externalAddr {
 		go func() {

setup/config/config_global.go

@@ -34,6 +34,9 @@ type Global struct {
 	// Defaults to 24 hours.
 	KeyValidityPeriod time.Duration `yaml:"key_validity_period"`
 
+	// The server name to delegate server-server communications to, with optional port
+	WellKnownServerName string `yaml:"well_known_server_name"`
+
 	// Disables federation. Dendrite will not be able to make any outbound HTTP requests
 	// to other servers and the federation API will not be exposed.
 	DisableFederation bool `yaml:"disable_federation"`

setup/config/config_test.go

@@ -39,6 +39,7 @@ global:
   private_key: matrix_key.pem
   key_id: ed25519:auto
   key_validity_period: 168h0m0s
+  well_known_server_name: "localhost:443"
   trusted_third_party_id_servers:
   - matrix.org
   - vector.im

setup/monolith.go

@@ -57,7 +57,7 @@ type Monolith struct {
 }
 
 // AddAllPublicRoutes attaches all public paths to the given router
-func (m *Monolith) AddAllPublicRoutes(process *process.ProcessContext, csMux, ssMux, keyMux, mediaMux, synapseMux *mux.Router) {
+func (m *Monolith) AddAllPublicRoutes(process *process.ProcessContext, csMux, ssMux, keyMux, wkMux, mediaMux, synapseMux *mux.Router) {
 	clientapi.AddPublicRoutes(
 		csMux, synapseMux, &m.Config.ClientAPI, m.AccountDB,
 		m.FedClient, m.RoomserverAPI,
@@ -66,7 +66,7 @@ func (m *Monolith) AddAllPublicRoutes(process *process.ProcessContext, csMux, ss
 		&m.Config.MSCs,
 	)
 	federationapi.AddPublicRoutes(
-		ssMux, keyMux, &m.Config.FederationAPI, m.UserAPI, m.FedClient,
+		ssMux, keyMux, wkMux, &m.Config.FederationAPI, m.UserAPI, m.FedClient,
 		m.KeyRing, m.RoomserverAPI, m.FederationSenderAPI,
 		m.EDUInternalAPI, m.KeyAPI, &m.Config.MSCs, nil,
 	)