Log websocket statistics

backend/src/api/websocket-handler.ts

@@ -26,6 +26,10 @@ class WebsocketHandler {
   private wss: WebSocket.Server | undefined;
   private extraInitProperties = {};
 
+  private numClients = 0;
+  private numConnected = 0;
+  private numDisconnected = 0;
+
   constructor() { }
 
   setWebsocketServer(wss: WebSocket.Server) {
@@ -42,7 +46,11 @@ class WebsocketHandler {
     }
 
     this.wss.on('connection', (client: WebSocket) => {
+      this.numConnected++;
       client.on('error', logger.info);
+      client.on('close', () => {
+        this.numDisconnected++;
+      });
       client.on('message', async (message: string) => {
         try {
           const parsedMessage: WebsocketResponse = JSON.parse(message);
@@ -232,6 +240,8 @@ class WebsocketHandler {
       throw new Error('WebSocket.Server is not set');
     }
 
+    this.printLogs();
+
     this.wss.clients.forEach((client) => {
       if (client.readyState !== WebSocket.OPEN) {
         return;
@@ -253,6 +263,8 @@ class WebsocketHandler {
       throw new Error('WebSocket.Server is not set');
     }
 
+    this.printLogs();
+
     if (config.MEMPOOL.ADVANCED_GBT_MEMPOOL) {
       await mempoolBlocks.$updateBlockTemplates(newMempool, newTransactions, deletedTransactions.map(tx => tx.txid), true);
     } else {
@@ -421,6 +433,8 @@ class WebsocketHandler {
       throw new Error('WebSocket.Server is not set');
     }
 
+    this.printLogs();
+
     const _memPool = memPool.getMempool();
 
     if (config.MEMPOOL.AUDIT) {
@@ -597,6 +611,17 @@ class WebsocketHandler {
       client.send(JSON.stringify(response));
     });
   }
+
+  private printLogs(): void {
+    if (this.wss) {
+      const count = this.wss?.clients?.size || 0;
+      const diff = count - this.numClients;
+      this.numClients = count;
+      logger.debug(`${count} websocket clients | ${this.numConnected} connected | ${this.numDisconnected} disconnected | (${diff >= 0 ? '+' : ''}${diff})`);
+      this.numConnected = 0;
+      this.numDisconnected = 0;
+    }
+  }
 }
 
 export default new WebsocketHandler();