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 f5a4e4a339b6f94ec215778dca22204adaa893d1.

* 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 368675283fc44501f227639811bdb16dd5deef8c.

* 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 13f9028e7a63662759ce7c55504a9d2423058668
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 15:47:14 2022 +0000

    Do the same for leave

commit e6be7f05c349fafbdddfe818337a17a60c867be1
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 15:33:42 2022 +0000

    Enforce state key matches sender

commit 85ede6d64bf10ce9b91cdd6d80f87350ee55242f
Author: Neil Alexander <neilalexander@users.noreply.github.com>
Date:   Tue Jan 4 14:07:04 2022 +0000

    Fix panics on closed channel sends

commit 9755494a98bed62450f8001d8128e40481d27e15
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 3bb4f87b5dd56882febb4db5621db484c8789b7c
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 368675283fc44501f227639811bdb16dd5deef8c.

commit fe2673ed7be9559eaca134424e403a4faca100b0
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 368675283fc44501f227639811bdb16dd5deef8c
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 b028dfc08577bcf52e6cb498026e15fa5d46d07c
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>

5 files changed, 53 insertions, 71 deletions

diff --git a/setup/config/config.go b/setup/config/config.go
index 404b7178..eb371a54 100644
--- a/setup/config/config.go
+++ b/setup/config/config.go
@@ -40,7 +40,7 @@ var keyIDRegexp = regexp.MustCompile("^ed25519:[a-zA-Z0-9_]+$")
 
 // Version is the current version of the config format.
 // This will change whenever we make breaking changes to the config format.
-const Version = 1
+const Version = 2
 
 // Dendrite contains all the config used by a dendrite process.
 // Relative paths are resolved relative to the current working directory
@@ -292,7 +292,7 @@ func (config *Dendrite) Derive() error {
 
 // SetDefaults sets default config values if they are not explicitly set.
 func (c *Dendrite) Defaults(generate bool) {
-	c.Version = 1
+	c.Version = Version
 
 	c.Global.Defaults(generate)
 	c.ClientAPI.Defaults(generate)
@@ -325,6 +325,7 @@ func (c *Dendrite) Verify(configErrs *ConfigErrors, isMonolith bool) {
 }
 
 func (c *Dendrite) Wiring() {
+	c.Global.JetStream.Matrix = &c.Global
 	c.ClientAPI.Matrix = &c.Global
 	c.EDUServer.Matrix = &c.Global
 	c.FederationAPI.Matrix = &c.Global
@@ -420,7 +421,11 @@ func (config *Dendrite) check(_ bool) error { // monolithic
 
 	if config.Version != Version {
 		configErrs.Add(fmt.Sprintf(
-			"unknown config version %q, expected %q", config.Version, Version,
+			"config version is %q, expected %q - this means that the format of the configuration "+
+				"file has changed in some significant way, so please revisit the sample config "+
+				"and ensure you are not missing any important options that may have been added "+
+				"or changed recently!",
+			config.Version, Version,
 		))
 		return configErrs
 	}
diff --git a/setup/config/config_global.go b/setup/config/config_global.go
index 20ee6d37..6f2306a6 100644
--- a/setup/config/config_global.go
+++ b/setup/config/config_global.go
@@ -46,8 +46,8 @@ type Global struct {
 	// Defaults to an empty array.
 	TrustedIDServers []string `yaml:"trusted_third_party_id_servers"`
 
-	// Kafka/Naffka configuration
-	Kafka Kafka `yaml:"kafka"`
+	// JetStream configuration
+	JetStream JetStream `yaml:"jetstream"`
 
 	// Metrics configuration
 	Metrics Metrics `yaml:"metrics"`
@@ -68,7 +68,7 @@ func (c *Global) Defaults(generate bool) {
 	}
 	c.KeyValidityPeriod = time.Hour * 24 * 7
 
-	c.Kafka.Defaults(generate)
+	c.JetStream.Defaults(generate)
 	c.Metrics.Defaults(generate)
 	c.DNSCache.Defaults()
 	c.Sentry.Defaults()
@@ -78,7 +78,7 @@ func (c *Global) Verify(configErrs *ConfigErrors, isMonolith bool) {
 	checkNotEmpty(configErrs, "global.server_name", string(c.ServerName))
 	checkNotEmpty(configErrs, "global.private_key", string(c.PrivateKeyPath))
 
-	c.Kafka.Verify(configErrs, isMonolith)
+	c.JetStream.Verify(configErrs, isMonolith)
 	c.Metrics.Verify(configErrs, isMonolith)
 	c.Sentry.Verify(configErrs, isMonolith)
 	c.DNSCache.Verify(configErrs, isMonolith)
diff --git a/setup/config/config_jetstream.go b/setup/config/config_jetstream.go
new file mode 100644
index 00000000..0bd84899
--- /dev/null
+++ b/setup/config/config_jetstream.go
@@ -0,0 +1,40 @@
+package config
+
+import (
+	"fmt"
+)
+
+type JetStream struct {
+	Matrix *Global `yaml:"-"`
+
+	// Persistent directory to store JetStream streams in.
+	StoragePath Path `yaml:"storage_path"`
+	// A list of NATS addresses to connect to. If none are specified, an
+	// internal NATS server will be used when running in monolith mode only.
+	Addresses []string `yaml:"addresses"`
+	// The prefix to use for stream names for this homeserver - really only
+	// useful if running more than one Dendrite on the same NATS deployment.
+	TopicPrefix string `yaml:"topic_prefix"`
+	// Keep all storage in memory. This is mostly useful for unit tests.
+	InMemory bool `yaml:"in_memory"`
+}
+
+func (c *JetStream) TopicFor(name string) string {
+	return fmt.Sprintf("%s%s", c.TopicPrefix, name)
+}
+
+func (c *JetStream) Defaults(generate bool) {
+	c.Addresses = []string{}
+	c.TopicPrefix = "Dendrite"
+	if generate {
+		c.StoragePath = Path("./")
+	}
+}
+
+func (c *JetStream) Verify(configErrs *ConfigErrors, isMonolith bool) {
+	// If we are running in a polylith deployment then we need at least
+	// one NATS JetStream server to talk to.
+	if !isMonolith {
+		checkNotZero(configErrs, "global.jetstream.addresses", int64(len(c.Addresses)))
+	}
+}
diff --git a/setup/config/config_kafka.go b/setup/config/config_kafka.go
deleted file mode 100644
index 5a61f17e..00000000
--- a/setup/config/config_kafka.go
+++ /dev/null
@@ -1,63 +0,0 @@
-package config
-
-import "fmt"
-
-// Defined Kafka topics.
-const (
-	TopicOutputTypingEvent       = "OutputTypingEvent"
-	TopicOutputSendToDeviceEvent = "OutputSendToDeviceEvent"
-	TopicOutputKeyChangeEvent    = "OutputKeyChangeEvent"
-	TopicOutputRoomEvent         = "OutputRoomEvent"
-	TopicOutputClientData        = "OutputClientData"
-	TopicOutputReceiptEvent      = "OutputReceiptEvent"
-)
-
-type Kafka struct {
-	// A list of kafka addresses to connect to.
-	Addresses []string `yaml:"addresses"`
-	// The prefix to use for Kafka topic names for this homeserver - really only
-	// useful if running more than one Dendrite on the same Kafka deployment.
-	TopicPrefix string `yaml:"topic_prefix"`
-	// Whether to use naffka instead of kafka.
-	// Naffka can only be used when running dendrite as a single monolithic server.
-	// Kafka can be used both with a monolithic server and when running the
-	// components as separate servers.
-	UseNaffka bool `yaml:"use_naffka"`
-	// The Naffka database is used internally by the naffka library, if used.
-	Database DatabaseOptions `yaml:"naffka_database"`
-	// The max size a Kafka message passed between consumer/producer can have
-	// Equals roughly max.message.bytes / fetch.message.max.bytes in Kafka
-	MaxMessageBytes *int `yaml:"max_message_bytes"`
-}
-
-func (k *Kafka) TopicFor(name string) string {
-	return fmt.Sprintf("%s%s", k.TopicPrefix, name)
-}
-
-func (c *Kafka) Defaults(generate bool) {
-	c.UseNaffka = true
-	c.Database.Defaults(10)
-	if generate {
-		c.Addresses = []string{"localhost:2181"}
-		c.Database.ConnectionString = DataSource("file:naffka.db")
-	}
-	c.TopicPrefix = "Dendrite"
-
-	maxBytes := 1024 * 1024 * 8 // about 8MB
-	c.MaxMessageBytes = &maxBytes
-}
-
-func (c *Kafka) Verify(configErrs *ConfigErrors, isMonolith bool) {
-	if c.UseNaffka {
-		if !isMonolith {
-			configErrs.Add("naffka can only be used in a monolithic server")
-		}
-		checkNotEmpty(configErrs, "global.kafka.database.connection_string", string(c.Database.ConnectionString))
-	} else {
-		// If we aren't using naffka then we need to have at least one kafka
-		// server to talk to.
-		checkNotZero(configErrs, "global.kafka.addresses", int64(len(c.Addresses)))
-	}
-	checkNotEmpty(configErrs, "global.kafka.topic_prefix", string(c.TopicPrefix))
-	checkPositive(configErrs, "global.kafka.max_message_bytes", int64(*c.MaxMessageBytes))
-}
diff --git a/setup/config/config_test.go b/setup/config/config_test.go
index ffe9edab..5aa54929 100644
--- a/setup/config/config_test.go
+++ b/setup/config/config_test.go
@@ -33,7 +33,7 @@ func TestLoadConfigRelative(t *testing.T) {
 }
 
 const testConfig = `
-version: 1
+version: 2
 global:
   server_name: localhost
   private_key: matrix_key.pem