Refactor notifications (#2688)

This PR changes the handling of notifications
- removes the `StreamEvent` and `ReadUpdate` stream
- listens on the `OutputRoomEvent` stream in the UserAPI to inform the
SyncAPI about unread notifications
- listens on the `OutputReceiptEvent` stream in the UserAPI to set
receipts/update notifications
- sets the `read_markers` directly from within the internal UserAPI

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>

userapi/consumers/clientapi.go

@@ -0,0 +1,127 @@
+// Copyright 2022 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package consumers
+
+import (
+	"context"
+
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/nats-io/nats.go"
+	log "github.com/sirupsen/logrus"
+
+	"github.com/matrix-org/dendrite/internal/pushgateway"
+	"github.com/matrix-org/dendrite/userapi/storage"
+
+	"github.com/matrix-org/dendrite/setup/config"
+	"github.com/matrix-org/dendrite/setup/jetstream"
+	"github.com/matrix-org/dendrite/setup/process"
+	"github.com/matrix-org/dendrite/userapi/producers"
+	"github.com/matrix-org/dendrite/userapi/util"
+)
+
+// OutputReceiptEventConsumer consumes events that originated in the clientAPI.
+type OutputReceiptEventConsumer struct {
+	ctx          context.Context
+	jetstream    nats.JetStreamContext
+	durable      string
+	topic        string
+	db           storage.Database
+	serverName   gomatrixserverlib.ServerName
+	syncProducer *producers.SyncAPI
+	pgClient     pushgateway.Client
+}
+
+// NewOutputReceiptEventConsumer creates a new OutputReceiptEventConsumer.
+// Call Start() to begin consuming from the EDU server.
+func NewOutputReceiptEventConsumer(
+	process *process.ProcessContext,
+	cfg *config.UserAPI,
+	js nats.JetStreamContext,
+	store storage.Database,
+	syncProducer *producers.SyncAPI,
+	pgClient pushgateway.Client,
+) *OutputReceiptEventConsumer {
+	return &OutputReceiptEventConsumer{
+		ctx:          process.Context(),
+		jetstream:    js,
+		topic:        cfg.Matrix.JetStream.Prefixed(jetstream.OutputReceiptEvent),
+		durable:      cfg.Matrix.JetStream.Durable("UserAPIReceiptConsumer"),
+		db:           store,
+		serverName:   cfg.Matrix.ServerName,
+		syncProducer: syncProducer,
+		pgClient:     pgClient,
+	}
+}
+
+// Start consuming receipts events.
+func (s *OutputReceiptEventConsumer) Start() error {
+	return jetstream.JetStreamConsumer(
+		s.ctx, s.jetstream, s.topic, s.durable, 1,
+		s.onMessage, nats.DeliverAll(), nats.ManualAck(),
+	)
+}
+
+func (s *OutputReceiptEventConsumer) onMessage(ctx context.Context, msgs []*nats.Msg) bool {
+	msg := msgs[0] // Guaranteed to exist if onMessage is called
+
+	userID := msg.Header.Get(jetstream.UserID)
+	roomID := msg.Header.Get(jetstream.RoomID)
+	readPos := msg.Header.Get(jetstream.EventID)
+	evType := msg.Header.Get("type")
+
+	if readPos == "" || evType != "m.read" {
+		return true
+	}
+
+	log := log.WithFields(log.Fields{
+		"room_id": roomID,
+		"user_id": userID,
+	})
+
+	localpart, domain, err := gomatrixserverlib.SplitID('@', userID)
+	if err != nil {
+		log.WithError(err).Error("userapi clientapi consumer: SplitID failure")
+		return true
+	}
+	if domain != s.serverName {
+		return true
+	}
+
+	metadata, err := msg.Metadata()
+	if err != nil {
+		return false
+	}
+
+	updated, err := s.db.SetNotificationsRead(ctx, localpart, roomID, uint64(gomatrixserverlib.AsTimestamp(metadata.Timestamp)), true)
+	if err != nil {
+		log.WithError(err).Error("userapi EDU consumer")
+		return false
+	}
+
+	if err = s.syncProducer.GetAndSendNotificationData(ctx, userID, roomID); err != nil {
+		log.WithError(err).Error("userapi EDU consumer: GetAndSendNotificationData failed")
+		return false
+	}
+
+	if !updated {
+		return true
+	}
+	if err = util.NotifyUserCountsAsync(ctx, s.pgClient, localpart, s.db); err != nil {
+		log.WithError(err).Error("userapi EDU consumer: NotifyUserCounts failed")
+		return false
+	}
+
+	return true
+}