Add NATS JetStream support (#1866)

* Add NATS JetStream support
Update shopify/sarama

* Fix addresses

* Don't change Addresses in Defaults

* Update saramajetstream

* Add missing error check

Keep typing events for at least one minute

* Use all configured NATS addresses

* Update saramajetstream

* Try setting up with NATS

* Make sure NATS uses own persistent directory (TODO: make this configurable)

* Update go.mod/go.sum

* Jetstream package

* Various other refactoring

* Build fixes

* Config tweaks, make random jetstream storage path for CI

* Disable interest policies

* Try to sane default on jetstream base path

* Try to use in-memory for CI

* Restore storage/retention

* Update nats.go dependency

* Adapt changes to config

* Remove unneeded TopicFor

* Dep update

* Revert "Remove unneeded TopicFor"

This reverts commit f5a4e4a339.

* Revert changes made to streams

* Fix build problems

* Update nats-server

* Update go.mod/go.sum

* Roomserver input API queuing using NATS

* Fix topic naming

* Prometheus metrics

* More refactoring to remove saramajetstream

* Add missing topic

* Don't try to populate map that doesn't exist

* Roomserver output topic

* Update go.mod/go.sum

* Message acknowledgements

* Ack tweaks

* Try to resume transaction re-sends

* Try to resume transaction re-sends

* Update to matrix-org/gomatrixserverlib@91dadfb

* Remove internal.PartitionStorer from components that don't consume keychanges

* Try to reduce re-allocations a bit in resolveConflictsV2

* Tweak delivery options on RS input

* Publish send-to-device messages into correct JetStream subject

* Async and sync roomserver input

* Update dendrite-config.yaml

* Remove roomserver tests for now (they need rewriting)

* Remove roomserver test again (was merged back in)

* Update documentation

* Docker updates

* More Docker updates

* Update Docker readme again

* Fix lint issues

* Send final event in `processEvent` synchronously (since this might stop Sytest from being so upset)

* Don't report event rejection errors via `/send`, since apparently this is upsetting tests that don't expect that

* Go 1.16 instead of Go 1.13 for upgrade tests and Complement

* Revert "Don't report event rejection errors via `/send`, since apparently this is upsetting tests that don't expect that"

This reverts commit 368675283f.

* Don't report any errors on `/send` to see what fun that creates

* Fix panics on closed channel sends

* Enforce state key matches sender

* Do the same for leave

* Various tweaks to make tests happier

Squashed commit of the following:

commit 13f9028e7a
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 15:47:14 2022 +0000

    Do the same for leave

commit e6be7f05c3
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 15:33:42 2022 +0000

    Enforce state key matches sender

commit 85ede6d64b
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 14:07:04 2022 +0000

    Fix panics on closed channel sends

commit 9755494a98
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 13:38:22 2022 +0000

    Don't report any errors on `/send` to see what fun that creates

commit 3bb4f87b5d
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 13:00:26 2022 +0000

    Revert "Don't report event rejection errors via `/send`, since apparently this is upsetting tests that don't expect that"

    This reverts commit 368675283f.

commit fe2673ed7b
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 12:09:34 2022 +0000

    Go 1.16 instead of Go 1.13 for upgrade tests and Complement

commit 368675283f
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 11:51:45 2022 +0000

    Don't report event rejection errors via `/send`, since apparently this is upsetting tests that don't expect that

commit b028dfc085
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 10:29:08 2022 +0000

    Send final event in `processEvent` synchronously (since this might stop Sytest from being so upset)

* Merge in NATS Server v2.6.6 and nats.go v1.13 into the in-process connection fork

* Add `jetstream.WithJetStreamMessage` to make ack/nak-ing less messy, use process context in consumers

* Fix consumer component name in  federation API

* Add comment explaining where streams are defined

* Tweaks to roomserver input with comments

* Finish that sentence that I apparently forgot to finish in INSTALL.md

* Bump version number of config to 2

* Add comments around asynchronous sends to roomserver in processEventWithMissingState

* More useful error message when the config version does not match

* Set version in generate-config

* Fix version in config.Defaults

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

setup/jetstream/helpers.go

@@ -0,0 +1,11 @@
+package jetstream
+
+import "github.com/nats-io/nats.go"
+
+func WithJetStreamMessage(msg *nats.Msg, f func(msg *nats.Msg) bool) {
+	if f(msg) {
+		_ = msg.Ack()
+	} else {
+		_ = msg.Nak()
+	}
+}

setup/jetstream/nats.go

@@ -0,0 +1,93 @@
+package jetstream
+
+import (
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/Shopify/sarama"
+	"github.com/matrix-org/dendrite/setup/config"
+	"github.com/sirupsen/logrus"
+
+	saramajs "github.com/S7evinK/saramajetstream"
+	natsserver "github.com/nats-io/nats-server/v2/server"
+	"github.com/nats-io/nats.go"
+	natsclient "github.com/nats-io/nats.go"
+)
+
+var natsServer *natsserver.Server
+var natsServerMutex sync.Mutex
+
+func Prepare(cfg *config.JetStream) (nats.JetStreamContext, sarama.Consumer, sarama.SyncProducer) {
+	// check if we need an in-process NATS Server
+	if len(cfg.Addresses) != 0 {
+		return setupNATS(cfg, nil)
+	}
+	natsServerMutex.Lock()
+	if natsServer == nil {
+		var err error
+		natsServer, err = natsserver.NewServer(&natsserver.Options{
+			ServerName:       "monolith",
+			DontListen:       true,
+			JetStream:        true,
+			StoreDir:         string(cfg.StoragePath),
+			NoSystemAccount:  true,
+			AllowNewAccounts: false,
+		})
+		if err != nil {
+			panic(err)
+		}
+		natsServer.ConfigureLogger()
+		go natsServer.Start()
+	}
+	natsServerMutex.Unlock()
+	if !natsServer.ReadyForConnections(time.Second * 10) {
+		logrus.Fatalln("NATS did not start in time")
+	}
+	nc, err := natsclient.Connect("", natsclient.InProcessServer(natsServer))
+	if err != nil {
+		logrus.Fatalln("Failed to create NATS client")
+	}
+	return setupNATS(cfg, nc)
+}
+
+func setupNATS(cfg *config.JetStream, nc *natsclient.Conn) (nats.JetStreamContext, sarama.Consumer, sarama.SyncProducer) {
+	if nc == nil {
+		var err error
+		nc, err = nats.Connect(strings.Join(cfg.Addresses, ","))
+		if err != nil {
+			logrus.WithError(err).Panic("Unable to connect to NATS")
+			return nil, nil, nil
+		}
+	}
+
+	s, err := nc.JetStream()
+	if err != nil {
+		logrus.WithError(err).Panic("Unable to get JetStream context")
+		return nil, nil, nil
+	}
+
+	for _, stream := range streams { // streams are defined in streams.go
+		name := cfg.TopicFor(stream.Name)
+		info, err := s.StreamInfo(name)
+		if err != nil && err != natsclient.ErrStreamNotFound {
+			logrus.WithError(err).Fatal("Unable to get stream info")
+		}
+		if info == nil {
+			stream.Subjects = []string{name}
+			// If we're trying to keep everything in memory (e.g. unit tests)
+			// then overwrite the storage policy.
+			if cfg.InMemory {
+				stream.Storage = nats.MemoryStorage
+			}
+
+			if _, err = s.AddStream(stream); err != nil {
+				logrus.WithError(err).WithField("stream", name).Fatal("Unable to add stream")
+			}
+		}
+	}
+
+	consumer := saramajs.NewJetStreamConsumer(nc, s, "")
+	producer := saramajs.NewJetStreamProducer(nc, s, "")
+	return s, consumer, producer
+}

setup/jetstream/streams.go

@@ -0,0 +1,61 @@
+package jetstream
+
+import (
+	"time"
+
+	"github.com/nats-io/nats.go"
+)
+
+const (
+	UserID = "user_id"
+	RoomID = "room_id"
+)
+
+var (
+	InputRoomEvent          = "InputRoomEvent"
+	OutputRoomEvent         = "OutputRoomEvent"
+	OutputSendToDeviceEvent = "OutputSendToDeviceEvent"
+	OutputKeyChangeEvent    = "OutputKeyChangeEvent"
+	OutputTypingEvent       = "OutputTypingEvent"
+	OutputClientData        = "OutputClientData"
+	OutputReceiptEvent      = "OutputReceiptEvent"
+)
+
+var streams = []*nats.StreamConfig{
+	{
+		Name:      InputRoomEvent,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.FileStorage,
+	},
+	{
+		Name:      OutputRoomEvent,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.FileStorage,
+	},
+	{
+		Name:      OutputSendToDeviceEvent,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.FileStorage,
+	},
+	{
+		Name:      OutputKeyChangeEvent,
+		Retention: nats.LimitsPolicy,
+		Storage:   nats.FileStorage,
+	},
+	{
+		Name:      OutputTypingEvent,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.MemoryStorage,
+		MaxAge:    time.Second * 60,
+	},
+	{
+		Name:      OutputClientData,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.FileStorage,
+	},
+	{
+		Name:      OutputReceiptEvent,
+		Retention: nats.InterestPolicy,
+		Storage:   nats.FileStorage,
+	},
+}