Hook up federation event receiving

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

@@ -18,11 +18,14 @@ import (
 	"encoding/base64"
 	"net/http"
 	"os"
+	"strings"
 	"time"
 
+	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/federationapi/config"
 	"github.com/matrix-org/dendrite/federationapi/routing"
+	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
 
 	log "github.com/Sirupsen/logrus"
@@ -40,7 +43,10 @@ var (
 	//  openssl x509 -noout -fingerprint -sha256 -inform pem -in server.crt |\
 	//     python -c 'print raw_input()[19:].replace(":","").decode("hex").encode("base64").rstrip("=\n")'
 	//
-	tlsFingerprint = os.Getenv("TLS_FINGERPRINT")
+	tlsFingerprint       = os.Getenv("TLS_FINGERPRINT")
+	kafkaURIs            = strings.Split(os.Getenv("KAFKA_URIS"), ",")
+	roomserverURL        = os.Getenv("ROOMSERVER_URL")
+	roomserverInputTopic = os.Getenv("TOPIC_INPUT_ROOM_EVENT")
 )
 
 func main() {
@@ -57,6 +63,18 @@ func main() {
 		log.Panic("No TLS_FINGERPRINT environment variable found.")
 	}
 
+	if len(kafkaURIs) == 0 {
+		// the kafka default is :9092
+		kafkaURIs = []string{"localhost:9092"}
+	}
+
+	if roomserverURL == "" {
+		log.Panic("No ROOMSERVER_URL environment variable found.")
+	}
+
+	if roomserverInputTopic == "" {
+		log.Panic("No TOPIC_INPUT_ROOM_EVENT environment variable found. This should match the roomserver input topic.")
+	}
 	cfg := config.FederationAPI{
 		ServerName: serverName,
 		// TODO: make the validity period configurable.
@@ -75,6 +93,37 @@ func main() {
 	}
 	cfg.TLSFingerPrints = []gomatrixserverlib.TLSFingerprint{{fingerprintSHA256}}
 
-	routing.Setup(http.DefaultServeMux, cfg)
+	federation := gomatrixserverlib.NewFederationClient(cfg.ServerName, cfg.KeyID, cfg.PrivateKey)
+
+	keyRing := gomatrixserverlib.KeyRing{
+		KeyFetchers: []gomatrixserverlib.KeyFetcher{
+			// TODO: Use perspective key fetchers for production.
+			&gomatrixserverlib.DirectKeyFetcher{federation.Client},
+		},
+		KeyDatabase: &dummyKeyDatabase{},
+	}
+	queryAPI := api.NewRoomserverQueryAPIHTTP(roomserverURL, nil)
+
+	roomserverProducer, err := producers.NewRoomserverProducer(kafkaURIs, roomserverInputTopic)
+	if err != nil {
+		log.Panicf("Failed to setup kafka producers(%s): %s", kafkaURIs, err)
+	}
+
+	routing.Setup(http.DefaultServeMux, cfg, queryAPI, roomserverProducer, keyRing)
 	log.Fatal(http.ListenAndServe(bindAddr, nil))
 }
+
+// TODO: Implement a proper key database.
+type dummyKeyDatabase struct{}
+
+func (d *dummyKeyDatabase) FetchKeys(
+	requests map[gomatrixserverlib.PublicKeyRequest]gomatrixserverlib.Timestamp,
+) (map[gomatrixserverlib.PublicKeyRequest]gomatrixserverlib.ServerKeys, error) {
+	return nil, nil
+}
+
+func (d *dummyKeyDatabase) StoreKeys(
+	map[gomatrixserverlib.PublicKeyRequest]gomatrixserverlib.ServerKeys,
+) error {
+	return nil
+}

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

@@ -16,21 +16,34 @@ package routing
 
 import (
 	"github.com/gorilla/mux"
+	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/federationapi/config"
 	"github.com/matrix-org/dendrite/federationapi/readers"
+	"github.com/matrix-org/dendrite/federationapi/writers"
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
 	"github.com/prometheus/client_golang/prometheus"
 	"net/http"
+	"time"
 )
 
 const (
-	pathPrefixV2Keys = "/_matrix/key/v2"
+	pathPrefixV2Keys       = "/_matrix/key/v2"
+	pathPrefixV1Federation = "/_matrix/federation/v1"
 )
 
 // Setup registers HTTP handlers with the given ServeMux.
-func Setup(servMux *http.ServeMux, cfg config.FederationAPI) {
+func Setup(
+	servMux *http.ServeMux,
+	cfg config.FederationAPI,
+	query api.RoomserverQueryAPI,
+	producer *producers.RoomserverProducer,
+	keys gomatrixserverlib.KeyRing,
+) {
 	apiMux := mux.NewRouter()
 	v2keysmux := apiMux.PathPrefix(pathPrefixV2Keys).Subrouter()
+	v1fedmux := apiMux.PathPrefix(pathPrefixV1Federation).Subrouter()
 
 	localKeys := makeAPI("localkeys", func(req *http.Request) util.JSONResponse {
 		return readers.LocalKeys(req, cfg)
@@ -43,6 +56,17 @@ func Setup(servMux *http.ServeMux, cfg config.FederationAPI) {
 	v2keysmux.Handle("/server/{keyID}", localKeys)
 	v2keysmux.Handle("/server/", localKeys)
 
+	v1fedmux.Handle("/send/{txnID}/", makeAPI("send",
+		func(req *http.Request) util.JSONResponse {
+			vars := mux.Vars(req)
+			return writers.Send(
+				req, gomatrixserverlib.TransactionID(vars["txnID"]),
+				time.Now(),
+				cfg, query, producer, keys,
+			)
+		},
+	))
+
 	servMux.Handle("/metrics", prometheus.Handler())
 	servMux.Handle("/api/", http.StripPrefix("/api", apiMux))
 }

src/github.com/matrix-org/dendrite/federationapi/writers/send.go

@@ -3,7 +3,9 @@ package writers
 import (
 	"encoding/json"
 	"fmt"
+	"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/federationapi/config"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -18,6 +20,8 @@ func Send(
 	txnID gomatrixserverlib.TransactionID,
 	now time.Time,
 	cfg config.FederationAPI,
+	query api.RoomserverQueryAPI,
+	producer *producers.RoomserverProducer,
 	keys gomatrixserverlib.KeyRing,
 ) util.JSONResponse {
 	request, errResp := gomatrixserverlib.VerifyHTTPRequest(req, now, cfg.ServerName, keys)
@@ -37,21 +41,76 @@ func Send(
 	content.TransactionID = txnID
 	content.Destination = cfg.ServerName
 
-	// TODO: process the transaction.
+	resp, err := processTransaction(content, query, producer, keys)
+	if err != nil {
+		return httputil.LogThenError(req, err)
+	}
 
 	return util.JSONResponse{
 		Code: 200,
-		JSON: gomatrixserverlib.RespSend{},
+		JSON: resp,
 	}
 }
 
-func processTransaction(t gomatrixserverlib.Transaction, query api.RoomserverQueryAPI) {
+func processTransaction(
+	t gomatrixserverlib.Transaction,
+	query api.RoomserverQueryAPI,
+	producer *producers.RoomserverProducer,
+	keys gomatrixserverlib.KeyRing,
+) (*gomatrixserverlib.RespSend, error) {
+	// Check the event signatures
+	if err := gomatrixserverlib.VerifyEventSignatures(t.PDUs, keys); err != nil {
+		return nil, err
+	}
 
+	// Process the events.
+	results := map[string]gomatrixserverlib.PDUResult{}
+	for _, e := range t.PDUs {
+		err := processEvent(e, query, producer)
+		if err != nil {
+			// If the error is due to the event itself being bad then we skip
+			// it and move onto the next event. We report an error so that the
+			// sender knows that we have skipped processing it.
+			//
+			// However if the event is due to a temporary failure in our server
+			// such as a database being unavailable then we should bail, and
+			// hope that the sender will retry when we are feeling better.
+			//
+			// It is uncertain what we should do if an event fails because
+			// we failed to fetch more information from the sending server.
+			// For example if a request to /state fails.
+			// If we skip the event then we risk missing the event until we
+			// receive another event referencing it.
+			// If we bail and stop processing then we risk wedging incoming
+			// transactions from that server forever.
+			switch err.(type) {
+			case unknownRoomError:
+			case *gomatrixserverlib.NotAllowed:
+			default:
+				// Any other error should be the result of a temporary error in
+				// our server so we should bail processing the transaction entirely.
+				return nil, err
+			}
+			results[e.EventID()] = gomatrixserverlib.PDUResult{err.Error()}
+		} else {
+			results[e.EventID()] = gomatrixserverlib.PDUResult{}
+		}
+	}
+
+	// TODO: Process the EDUs.
+
+	return &gomatrixserverlib.RespSend{PDUs: results}, nil
 }
 
-var errUnknownRoom = fmt.Errorf("unknown room")
+type unknownRoomError string
 
-func processEvent(e gomatrixserverlib.Event, query api.RoomserverQueryAPI) error {
+func (e unknownRoomError) Error() string { return fmt.Sprintf("unknown room %q", e) }
+
+func processEvent(
+	e gomatrixserverlib.Event,
+	query api.RoomserverQueryAPI,
+	producer *producers.RoomserverProducer,
+) error {
 	refs := e.PrevEvents()
 	prevEventIDs := make([]string, len(refs))
 	for i := range refs {
@@ -77,7 +136,7 @@ func processEvent(e gomatrixserverlib.Event, query api.RoomserverQueryAPI) error
 		// that this server is unaware of.
 		// However generally speaking we should reject events for rooms we
 		// aren't a member of.
-		return errUnknownRoom
+		return unknownRoomError(e.RoomID())
 	}
 
 	if !stateResp.PrevEventsExist {
@@ -101,6 +160,7 @@ func processEvent(e gomatrixserverlib.Event, query api.RoomserverQueryAPI) error
 		panic(fmt.Errorf("Receiving events with missing prev_events is no implemented"))
 	}
 
+	// Check that the event is allowed by the state at the event.
 	authUsingState := gomatrixserverlib.NewAuthEvents(nil)
 	for i := range stateResp.StateEvents {
 		authUsingState.AddEvent(&stateResp.StateEvents[i])
@@ -110,5 +170,13 @@ func processEvent(e gomatrixserverlib.Event, query api.RoomserverQueryAPI) error
 		return err
 	}
 
+	// TODO: Check that the roomserver has a copy of all of the auth_events.
+	// TODO: Check that the event is allowed by its auth_events.
+
+	// pass the event to the roomserver
+	if err := producer.SendEvents([]gomatrixserverlib.Event{e}); err != nil {
+		return err
+	}
+
 	return nil
 }