Read roomserver output log and remember position across restarts (#52)

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

@@ -25,4 +25,6 @@ type Sync struct {
 	RoomserverOutputTopic string
 	// A list of URIs to consume events from. These kafka logs should be produced by a Room Server.
 	KafkaConsumerURIs []string
+	// The postgres connection config for connecting to the database e.g a postgres:// URI
+	DataSource string
 }

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

@@ -48,8 +48,8 @@ func Setup(servMux *http.ServeMux, httpClient *http.Client, cfg config.ClientAPI
 	servMux.Handle("/api/", http.StripPrefix("/api", apiMux))
 }
 
-// SetupSyncServer configures the given mux with sync-server listeners
-func SetupSyncServer(servMux *http.ServeMux, httpClient *http.Client, cfg config.Sync) {
+// SetupSyncServerListeners configures the given mux with sync-server listeners
+func SetupSyncServerListeners(servMux *http.ServeMux, httpClient *http.Client, cfg config.Sync) {
 	apiMux := mux.NewRouter()
 	r0mux := apiMux.PathPrefix(pathPrefixR0).Subrouter()
 	r0mux.Handle("/sync", make("sync", util.NewJSONRequestHandler(func(req *http.Request) util.JSONResponse {

src/github.com/matrix-org/dendrite/clientapi/storage/syncserver.go

@@ -0,0 +1,39 @@
+package storage
+
+import (
+	"database/sql"
+
+	"github.com/matrix-org/dendrite/common"
+	// Import the postgres database driver.
+	_ "github.com/lib/pq"
+)
+
+// SyncServerDatabase represents a sync server database
+type SyncServerDatabase struct {
+	db         *sql.DB
+	partitions common.PartitionOffsetStatements
+}
+
+// NewSyncServerDatabase creates a new sync server database
+func NewSyncServerDatabase(dataSourceName string) (*SyncServerDatabase, error) {
+	var db *sql.DB
+	var err error
+	if db, err = sql.Open("postgres", dataSourceName); err != nil {
+		return nil, err
+	}
+	partitions := common.PartitionOffsetStatements{}
+	if err = partitions.Prepare(db); err != nil {
+		return nil, err
+	}
+	return &SyncServerDatabase{db, partitions}, nil
+}
+
+// PartitionOffsets implements common.PartitionStorer
+func (d *SyncServerDatabase) PartitionOffsets(topic string) ([]common.PartitionOffset, error) {
+	return d.partitions.SelectPartitionOffsets(topic)
+}
+
+// SetPartitionOffset implements common.PartitionStorer
+func (d *SyncServerDatabase) SetPartitionOffset(topic string, partition int32, offset int64) error {
+	return d.partitions.UpsertPartitionOffset(topic, partition, offset)
+}

src/github.com/matrix-org/dendrite/clientapi/sync/syncserver.go

@@ -0,0 +1,43 @@
+package sync
+
+import (
+	log "github.com/Sirupsen/logrus"
+	"github.com/matrix-org/dendrite/clientapi/config"
+	"github.com/matrix-org/dendrite/common"
+	sarama "gopkg.in/Shopify/sarama.v1"
+)
+
+// Server contains all the logic for running a sync server
+type Server struct {
+	roomServerConsumer *common.ContinualConsumer
+}
+
+// NewServer creates a new sync server. Call Start() to begin consuming from room servers.
+func NewServer(cfg *config.Sync, store common.PartitionStorer) (*Server, error) {
+	kafkaConsumer, err := sarama.NewConsumer(cfg.KafkaConsumerURIs, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	consumer := common.ContinualConsumer{
+		Topic:          cfg.RoomserverOutputTopic,
+		Consumer:       kafkaConsumer,
+		PartitionStore: store,
+	}
+	s := &Server{
+		roomServerConsumer: &consumer,
+	}
+	consumer.ProcessMessage = s.onMessage
+
+	return s, nil
+}
+
+// Start consuming from room servers
+func (s *Server) Start() error {
+	return s.roomServerConsumer.Start()
+}
+
+func (s *Server) onMessage(msg *sarama.ConsumerMessage) error {
+	log.WithField("key", string(msg.Key)).WithField("val", string(msg.Value)).Info("Recv")
+	return nil
+}

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

@@ -7,6 +7,8 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/config"
 	"github.com/matrix-org/dendrite/clientapi/routing"
+	"github.com/matrix-org/dendrite/clientapi/storage"
+	"github.com/matrix-org/dendrite/clientapi/sync"
 
 	log "github.com/Sirupsen/logrus"
 	"github.com/matrix-org/dugong"
@@ -40,10 +42,24 @@ func main() {
 	cfg := config.Sync{
 		KafkaConsumerURIs:     []string{"localhost:9092"},
 		RoomserverOutputTopic: "roomserverOutput",
+		DataSource:            "postgres://dendrite:itsasecret@localhost/syncserver?sslmode=disable",
 	}
 
 	log.Info("Starting sync server")
 
-	routing.SetupSyncServer(http.DefaultServeMux, http.DefaultClient, cfg)
+	db, err := storage.NewSyncServerDatabase(cfg.DataSource)
+	if err != nil {
+		log.Panicf("startup: failed to create sync server database with data source %s : %s", cfg.DataSource, err)
+	}
+
+	server, err := sync.NewServer(&cfg, db)
+	if err != nil {
+		log.Panicf("startup: failed to create sync server: %s", err)
+	}
+	if err = server.Start(); err != nil {
+		log.Panicf("startup: failed to start sync server")
+	}
+
+	routing.SetupSyncServerListeners(http.DefaultServeMux, http.DefaultClient, cfg)
 	log.Fatal(http.ListenAndServe(bindAddr, nil))
 }

src/github.com/matrix-org/dendrite/common/partition_offset_table.go

@@ -57,6 +57,7 @@ func (s *PartitionOffsetStatements) SelectPartitionOffsets(topic string) ([]Part
 		if err := rows.Scan(&offset.Partition, &offset.Offset); err != nil {
 			return nil, err
 		}
+		results = append(results, offset)
 	}
 	return results, nil
 }