Add websocket_idle_timeout_seconds config for idle WebSocket cleanup (#21493)

bbb-graphql-middleware/cmd/bbb-graphql-middleware/main.go

@@ -40,6 +40,9 @@ func main() {
 		log.Infof("Json Patch Disabled!")
 	}
 
+	// Routine to check for idle connections and close them
+	go websrv.InvalidateIdleBrowserConnectionsRoutine()
+
 	// Websocket listener
 
 	rateLimiter := common.NewCustomRateLimiter(cfg.Server.MaxConnectionsPerSecond)

bbb-graphql-middleware/config/Config.go

@@ -29,6 +29,7 @@ type Config struct {
 		JsonPatchDisabled             bool   `yaml:"json_patch_disabled"`
 		SubscriptionAllowedList       string `yaml:"subscriptions_allowed_list"`
 		SubscriptionsDeniedList       string `yaml:"subscriptions_denied_list"`
+		WebsocketIdleTimeoutSeconds   int    `yaml:"websocket_idle_timeout_seconds"`
 	} `yaml:"server"`
 	Redis struct {
 		Host     string `yaml:"host"`

bbb-graphql-middleware/config/config.yml

@@ -12,6 +12,7 @@ server:
   json_patch_disabled: false
   subscriptions_allowed_list:
   subscriptions_denied_list:
+  websocket_idle_timeout_seconds: 60
 redis:
   host: 127.0.0.1
   port: 6379

bbb-graphql-middleware/internal/common/types.go

@@ -6,6 +6,7 @@ import (
 	"github.com/sirupsen/logrus"
 	"net/http"
 	"sync"
+	"time"
 
 	"nhooyr.io/websocket"
 )
@@ -56,6 +57,8 @@ type BrowserConnection struct {
 	FromBrowserToHasuraChannel     *SafeChannelByte               // channel to transmit messages from Browser to Hasura
 	FromBrowserToGqlActionsChannel *SafeChannelByte               // channel to transmit messages from Browser to Graphq-Actions
 	FromHasuraToBrowserChannel     *SafeChannelByte               // channel to transmit messages from Hasura/GqlActions to Browser
+	LastBrowserMessageTime         time.Time                      // stores the time of the last message to control browser idleness
+	LastBrowserMessageTimeMutex    sync.RWMutex                   // mutex for LastBrowserMessageTime
 	Logger                         *logrus.Entry                  // connection logger populated with connection info
 }
 

bbb-graphql-middleware/internal/hasura/client.go

@@ -70,6 +70,7 @@ func HasuraClient(
 	defer func() {
 		//When Hasura sends an CloseError, it will forward the error to the browser and close the connection
 		if thisConnection.WebsocketCloseError != nil {
+			browserConnection.Logger.Infof("Closing browser connection because Hasura connection was closed, reason: %s", thisConnection.WebsocketCloseError.Reason)
 			browserConnection.Websocket.Close(thisConnection.WebsocketCloseError.Code, thisConnection.WebsocketCloseError.Reason)
 			browserConnection.ContextCancelFunc()
 		}

bbb-graphql-middleware/internal/websrv/connhandler.go

@@ -98,6 +98,7 @@ func ConnectionHandler(w http.ResponseWriter, r *http.Request) {
 		FromBrowserToHasuraChannel:     common.NewSafeChannelByte(bufferSize),
 		FromBrowserToGqlActionsChannel: common.NewSafeChannelByte(bufferSize),
 		FromHasuraToBrowserChannel:     common.NewSafeChannelByte(bufferSize),
+		LastBrowserMessageTime:         time.Now(),
 		Logger:                         connectionLogger,
 	}
 
@@ -494,3 +495,27 @@ func disconnectWithError(
 
 	return
 }
+
+var websocketIdleTimeoutSeconds = config.GetConfig().Server.WebsocketIdleTimeoutSeconds
+
+func InvalidateIdleBrowserConnectionsRoutine() {
+	for {
+		time.Sleep(15 * time.Second)
+
+		BrowserConnectionsMutex.RLock()
+		for _, browserConnection := range BrowserConnections {
+			browserConnection.LastBrowserMessageTimeMutex.RLock()
+			browserIdleSince := time.Since(browserConnection.LastBrowserMessageTime)
+			browserConnection.LastBrowserMessageTimeMutex.RUnlock()
+
+			if browserIdleSince > time.Duration(websocketIdleTimeoutSeconds)*time.Second {
+				browserConnection.Logger.Info("Closing browser connection, reason: idle timeout")
+				errCloseWs := browserConnection.Websocket.Close(websocket.StatusNormalClosure, "idle timeout")
+				if errCloseWs != nil {
+					browserConnection.Logger.Debugf("Error on close websocket: %v", errCloseWs)
+				}
+			}
+		}
+		BrowserConnectionsMutex.RUnlock()
+	}
+}

bbb-graphql-middleware/internal/websrv/reader/reader.go

@@ -35,6 +35,7 @@ func BrowserConnectionReader(
 
 	for {
 		messageType, message, err := browserConnection.Websocket.Read(browserConnection.Context)
+
 		if err != nil {
 			if errors.Is(err, context.Canceled) {
 				browserConnection.Logger.Debugf("Closing Browser ws connection as Context was cancelled!")
@@ -45,6 +46,9 @@ func BrowserConnectionReader(
 		}
 
 		browserConnection.Logger.Tracef("received from browser: %s", string(message))
+		browserConnection.LastBrowserMessageTimeMutex.Lock()
+		browserConnection.LastBrowserMessageTime = time.Now()
+		browserConnection.LastBrowserMessageTimeMutex.Unlock()
 
 		if messageType != websocket.MessageText {
 			browserConnection.Logger.Warnf("received non-text message: %v", messageType)