periodically send a ping message on the WS to avoid proxy auto-termin…

…ation of the socket. fixes #221

back-end/hub-editing/src/main/java/io/apicurio/hub/editing/EditApiDesignEndpoint.java

@@ -207,6 +207,9 @@ public void onMessage(Session session, JsonNode message) {
             // TODO send the new content version back to the originating user (with some sort of correlation) so the command can be properly sequenced
             editingSession.sendCommandToOthers(session, user, command);
             return;
+        } else if (msgType.equals("ping")) {
+            logger.debug("PING message received.");
+            return;
         }
         logger.error("Unknown message type: {}", msgType);
         // TODO something went wrong if we got here - report an error of some kind

front-end/app/studio/services/apis-hub.service.ts

@@ -47,24 +47,32 @@ class ApiEditingSession implements IApiEditingSession {
     private _commandHandler: ICommandHandler;
     private _oasLibrary: OasLibraryUtils;
 
+    private _connected: boolean;
+    private _pingIntervalId: number;
+
     /**
      * Constructor.
      * @param {EditableApiDefinition} api
      * @param {WebSocket} socket
      */
     constructor(private api: EditableApiDefinition, private socket: WebSocket) {
         this._oasLibrary = new OasLibraryUtils();
+        this._connected = false;
     }
 
     /**
      * Connects the websocket to the server.
      * @param {IConnectionHandler} handler
      */
     connect(handler: IConnectionHandler): void {
+        let me: ApiEditingSession = this;
         this._connectionHandler = handler;
         this.socket.onopen = () => {
             console.info("[ApiEditingSession] WS connection to server OPEN.");
+            this._connected = true;
             this._connectionHandler.onConnected();
+            // Start the 45s ping.
+            me.ping();
         };
         this.socket.onmessage = (msgEvent) => {
             console.info("[ApiEditingSession] Message received from server.");
@@ -83,13 +91,14 @@ class ApiEditingSession implements IApiEditingSession {
             }
         };
         this.socket.onclose = (event) => {
-            // TODO handle unexpected closure here somehow
             console.info("[ApiEditingSession] WS connection to server CLOSED: %o", event);
             if (event.code === 1000) {
                 this._connectionHandler.onClosed();
             } else {
                 this._connectionHandler.onDisconnected(event.code);
             }
+            this._connected = false;
+            window.clearInterval(this._pingIntervalId);
         };
     }
 
@@ -114,13 +123,32 @@ class ApiEditingSession implements IApiEditingSession {
         this.socket.send(dataStr);
     }
 
+    /**
+     * Called to send a ping message to the server.
+     */
+    sendPing(): void {
+        console.info("[ApiEditingSession] Sending PING.");
+        let data: any = {
+            type: "ping"
+        };
+        let dataStr: string = JSON.stringify(data);
+        this.socket.send(dataStr);
+    }
+
     /**
      * Called to close the connection with the server.  Should only be called
      * when the user leaves the editor.
      */
-    close() {
+    close(): void {
         this.socket.close();
     }
+
+    private ping(): void {
+        console.info("[ApiEditingSession] Starting the ping interval.");
+        this._pingIntervalId = window.setInterval(() => {
+            this.sendPing();
+        }, 45000);
+    }
 }