1 files changed, 104 insertions, 0 deletions
diff --git a/userapi/producers/syncapi.go b/userapi/producers/syncapi.go
new file mode 100644
index 00000000..4a206f33
--- /dev/null
+++ b/userapi/producers/syncapi.go
@@ -0,0 +1,104 @@
+package producers
+
+import (
+	"context"
+	"encoding/json"
+
+	"github.com/matrix-org/dendrite/internal/eventutil"
+	"github.com/matrix-org/dendrite/setup/jetstream"
+	"github.com/matrix-org/dendrite/userapi/storage"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/nats-io/nats.go"
+	log "github.com/sirupsen/logrus"
+)
+
+type JetStreamPublisher interface {
+	PublishMsg(*nats.Msg, ...nats.PubOpt) (*nats.PubAck, error)
+}
+
+// SyncAPI produces messages for the Sync API server to consume.
+type SyncAPI struct {
+	db                    storage.Database
+	producer              JetStreamPublisher
+	clientDataTopic       string
+	notificationDataTopic string
+}
+
+func NewSyncAPI(db storage.Database, js JetStreamPublisher, clientDataTopic string, notificationDataTopic string) *SyncAPI {
+	return &SyncAPI{
+		db:                    db,
+		producer:              js,
+		clientDataTopic:       clientDataTopic,
+		notificationDataTopic: notificationDataTopic,
+	}
+}
+
+// SendAccountData sends account data to the Sync API server.
+func (p *SyncAPI) SendAccountData(userID string, roomID string, dataType string) error {
+	m := &nats.Msg{
+		Subject: p.clientDataTopic,
+		Header:  nats.Header{},
+	}
+	m.Header.Set(jetstream.UserID, userID)
+
+	var err error
+	m.Data, err = json.Marshal(eventutil.AccountData{
+		RoomID: roomID,
+		Type:   dataType,
+	})
+	if err != nil {
+		return err
+	}
+
+	log.WithFields(log.Fields{
+		"user_id":   userID,
+		"room_id":   roomID,
+		"data_type": dataType,
+	}).Tracef("Producing to topic '%s'", p.clientDataTopic)
+
+	_, err = p.producer.PublishMsg(m)
+	return err
+}
+
+// GetAndSendNotificationData reads the database and sends data about unread
+// notifications to the Sync API server.
+func (p *SyncAPI) GetAndSendNotificationData(ctx context.Context, userID, roomID string) error {
+	localpart, _, err := gomatrixserverlib.SplitID('@', userID)
+	if err != nil {
+		return err
+	}
+
+	ntotal, nhighlight, err := p.db.GetRoomNotificationCounts(ctx, localpart, roomID)
+	if err != nil {
+		return err
+	}
+
+	return p.sendNotificationData(userID, &eventutil.NotificationData{
+		RoomID:                  roomID,
+		UnreadHighlightCount:    int(nhighlight),
+		UnreadNotificationCount: int(ntotal),
+	})
+}
+
+// sendNotificationData sends data about unread notifications to the Sync API server.
+func (p *SyncAPI) sendNotificationData(userID string, data *eventutil.NotificationData) error {
+	m := &nats.Msg{
+		Subject: p.notificationDataTopic,
+		Header:  nats.Header{},
+	}
+	m.Header.Set(jetstream.UserID, userID)
+
+	var err error
+	m.Data, err = json.Marshal(data)
+	if err != nil {
+		return err
+	}
+
+	log.WithFields(log.Fields{
+		"user_id": userID,
+		"room_id": data.RoomID,
+	}).Tracef("Producing to topic '%s'", p.clientDataTopic)
+
+	_, err = p.producer.PublishMsg(m)
+	return err
+}