lint: introduce stricter lints

Author: daniel-abramov

.golangci.yaml

@@ -1,20 +1,32 @@
 linters-settings:
-  lll:
-    line-length: 120
+  nlreturn:
+    block-size: 2
   wsl:
-    allow-cuddle-declarations: true
+    enforce-err-cuddling: true
+  funlen:
+    lines: 100
+    statements: 50
+  gomoddirectives:
+    replace-allow-list:
+      - maunium.net/go/mautrix # currently needed for the PoC to work (custom mautrix)
 
 linters:
   enable-all: true
   disable:
-    - nlreturn
-    - exhaustivestruct
-    - exhaustruct
-    - cyclop
-    - gochecknoglobals
-    - gomoddirectives
-    - exhaustive
-    - funlen
-    - gofumpt
-    - interfacer
-    - godox # We ought to enable this at some point
+    - ifshort # deprecated
+    - nosnakecase # deprecated
+    - interfacer # deprecated
+    - deadcode # deprecated
+    - exhaustivestruct # deprecated
+    - varcheck # deprecated
+    - structcheck # deprecated
+    - maligned # deprecated
+    - scopelint # deprecated
+    - golint # deprecated
+    - rowserrcheck # https://github.com/golangci/golangci-lint/issues/2649
+    - sqlclosecheck # https://github.com/golangci/golangci-lint/issues/2649
+    - wastedassign # https://github.com/golangci/golangci-lint/issues/2649
+    - gomnd # we use status code numbers and for our use case it's not practical
+    - godox # we have TODOs at this stage of the project, enable in future
+    - forbidigo # we use things like fmt.Printf for debugging, enable in future
+  fast: true

src/call.go

@@ -513,7 +513,7 @@ func (c *Call) SendDataChannelMessage(msg event.SFUMessage) {
 }
 
 func (c *Call) CheckKeepAliveTimestamp() {
-	timeout := time.Second * time.Duration(config.KeepAliveTimeout)
+	timeout := time.Second * time.Duration(c.conf.Config.KeepAliveTimeout)
 	for range time.Tick(timeout) {
 		if c.lastKeepAliveTimestamp.Add(timeout).Before(time.Now()) {
 			if c.PeerConnection.ConnectionState() != webrtc.PeerConnectionStateClosed {

src/conference.go

@@ -25,21 +25,32 @@ import (
 	"maunium.net/go/mautrix/id"
 )
 
-var ErrNoSuchCall = errors.New("no such call")
-var ErrFoundExistingCallWithSameSessionAndDeviceID = errors.New("found existing call with equal DeviceID and SessionID")
+var (
+	ErrNoSuchCall                                  = errors.New("no such call")
+	ErrFoundExistingCallWithSameSessionAndDeviceID = errors.New("found existing call with equal DeviceID and SessionID")
+)
+
+// Configuration for the group conferences (calls).
+type ConferenceConfig struct {
+	// Keep-alive timeout for WebRTC connections. If no keep-alive has been received
+	// from the client for this duration, the connection is considered dead.
+	KeepAliveTimeout int
+}
 
 type Conference struct {
 	ConfID string
-	Calls  map[string]*Call // By callID
+	Calls  map[string]*Call  // By callID
+	Config *ConferenceConfig // TODO: this must be protected by a mutex actually
 
 	mutex    sync.RWMutex
 	logger   *logrus.Entry
 	Metadata *Metadata
 }
 
-func NewConference(confID string) *Conference {
+func NewConference(confID string, config *ConferenceConfig) *Conference {
 	conference := new(Conference)
 
+	conference.Config = config
 	conference.ConfID = confID
 	conference.Calls = make(map[string]*Call)
 	conference.Metadata = NewMetadata(conference)

src/focus.go

@@ -38,15 +38,17 @@ type Focus struct {
 	client *mautrix.Client
 	confs  Confs
 	logger *logrus.Entry
+	config *ConferenceConfig
 }
 
-func NewFocus(name string, client *mautrix.Client) *Focus {
+func NewFocus(name string, client *mautrix.Client, config *ConferenceConfig) *Focus {
 	focus := new(Focus)
 
 	focus.name = name
 	focus.client = client
 	focus.confs.confs = make(map[string]*Conference)
 	focus.logger = logrus.WithFields(logrus.Fields{})
+	focus.config = config
 
 	return focus
 }
@@ -58,7 +60,7 @@ func (f *Focus) GetConf(confID string, create bool) (*Conference, error) {
 
 	if conference == nil {
 		if create {
-			conference = NewConference(confID)
+			conference = NewConference(confID, f.config)
 			f.confs.confs[confID] = conference
 		} else {
 			return nil, ErrNoSuchConference
@@ -69,9 +71,11 @@ func (f *Focus) GetConf(confID string, create bool) (*Conference, error) {
 }
 
 func (f *Focus) getExistingCall(confID string, callID string) (*Call, error) {
-	var conf *Conference
-	var call *Call
-	var err error
+	var (
+		conf *Conference
+		call *Call
+		err  error
+	)
 
 	if conf, err = f.GetConf(confID, false); err != nil || conf == nil {
 		f.logger.Printf("failed to get conf %s: %s", confID, err)
@@ -110,9 +114,11 @@ func (f *Focus) onEvent(_ mautrix.EventSource, evt *event.Event) {
 		return
 	}
 
-	var conf *Conference
-	var call *Call
-	var err error
+	var (
+		conf *Conference
+		call *Call
+		err  error
+	)
 
 	switch evt.Type.Type {
 	case event.ToDeviceCallInvite.Type:

src/main.go

@@ -27,13 +27,6 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-var config *Config
-
-var logTime = flag.Bool("logTime", false, "whether or not to print time and date in logs")
-var configFilePath = flag.String("config", "config.yaml", "configuration file path")
-var cpuProfile = flag.String("cpuProfile", "", "write CPU profile to `file`")
-var memProfile = flag.String("memProfile", "", "write memory profile to `file`")
-
 func initCPUProfiling(cpuProfile *string) func() {
 	logrus.Info("initializing CPU profiling")
 
@@ -95,6 +88,13 @@ func killListener(c chan os.Signal, beforeExit []func()) {
 }
 
 func main() {
+	var (
+		logTime        = flag.Bool("logTime", false, "whether or not to print time and date in logs")
+		configFilePath = flag.String("config", "config.yaml", "configuration file path")
+		cpuProfile     = flag.String("cpuProfile", "", "write CPU profile to `file`")
+		memProfile     = flag.String("memProfile", "", "write memory profile to `file`")
+	)
+
 	flag.Parse()
 
 	initLogging(logTime)
@@ -115,12 +115,10 @@ func main() {
 
 	go killListener(c, beforeExit)
 
-	var err error
-	config, err = loadConfig(*configFilePath)
-
+	config, err := loadConfig(*configFilePath)
 	if err != nil {
 		logrus.WithError(err).Fatal("could not load config")
 	}
 
-	InitMatrix()
+	InitMatrix(config)
 }

src/matrix.go

@@ -25,7 +25,7 @@ import (
 
 const localSessionID = "sfu"
 
-func InitMatrix() {
+func InitMatrix(config *Config) {
 	client, err := mautrix.NewClient(config.HomeserverURL, config.UserID, config.AccessToken)
 	if err != nil {
 		logrus.WithError(err).Fatal("Failed to create client")
@@ -43,7 +43,11 @@ func InitMatrix() {
 	logrus.WithField("device_id", whoami.DeviceID).Info("Identified SFU as DeviceID")
 	client.DeviceID = whoami.DeviceID
 
-	focus := NewFocus(fmt.Sprintf("%s (%s)", config.UserID, client.DeviceID), client)
+	focus := NewFocus(
+		fmt.Sprintf("%s (%s)", config.UserID, client.DeviceID),
+		client,
+		&ConferenceConfig{KeepAliveTimeout: config.KeepAliveTimeout},
+	)
 
 	syncer, ok := client.Syncer.(*mautrix.DefaultSyncer)
 	if !ok {