From b978b3bc2f8beb099632465dc8b00c03af10b338 Mon Sep 17 00:00:00 2001
From: Dave Horton <daveh@beachdognet.com>
Date: Mon, 5 Jun 2023 11:00:14 -0400
Subject: [PATCH] add optional ws ping (#370)

---
 lib/config.js             |  3 ++-
 lib/utils/ws-requestor.js | 16 ++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/lib/config.js b/lib/config.js
index 7dd1b1d3..268eab83 100644
--- a/lib/config.js
+++ b/lib/config.js
@@ -51,7 +51,7 @@ const JAMBONES_SBCS = process.env.JAMBONES_SBCS;
 /* websockets */
 const JAMBONES_WS_HANDSHAKE_TIMEOUT_MS = parseInt(process.env.JAMBONES_WS_HANDSHAKE_TIMEOUT_MS, 10) || 1500;
 const JAMBONES_WS_MAX_PAYLOAD = parseInt(process.env.JAMBONES_WS_MAX_PAYLOAD, 10) || 24 * 1024;
-
+const JAMBONES_WS_PING_INTERVAL_MS = parseInt(process.env.JAMBONES_WS_PING_INTERVAL_MS, 10) || 0;
 const MAX_RECONNECTS = 5;
 const RESPONSE_TIMEOUT_MS = parseInt(process.env.JAMBONES_WS_API_MSG_RESPONSE_TIMEOUT, 10) || 5000;
 
@@ -186,6 +186,7 @@ module.exports = {
   RESPONSE_TIMEOUT_MS,
   JAMBONES_WS_HANDSHAKE_TIMEOUT_MS,
   JAMBONES_WS_MAX_PAYLOAD,
+  JAMBONES_WS_PING_INTERVAL_MS,
   MAX_RECONNECTS,
   GCP_JSON_KEY,
   MICROSOFT_REGION,
diff --git a/lib/utils/ws-requestor.js b/lib/utils/ws-requestor.js
index ffc58903..2c0f14d4 100644
--- a/lib/utils/ws-requestor.js
+++ b/lib/utils/ws-requestor.js
@@ -6,6 +6,7 @@ const Websocket = require('ws');
 const snakeCaseKeys = require('./snakecase-keys');
 const {
   RESPONSE_TIMEOUT_MS,
+  JAMBONES_WS_PING_INTERVAL_MS,
   MAX_RECONNECTS,
   JAMBONES_WS_HANDSHAKE_TIMEOUT_MS,
   JAMBONES_WS_MAX_PAYLOAD
@@ -178,9 +179,17 @@ class WsRequestor extends BaseRequestor {
     });
   }
 
+  _stopPingTimer() {
+    if (this._pingTimer) {
+      clearInterval(this._pingTimer);
+      this._pingTimer = null;
+    }
+  }
+
   close() {
     this.closedGracefully = true;
     this.logger.debug('WsRequestor:close closing socket');
+    this._stopPingTimer();
     try {
       if (this.ws) {
         this.ws.close(1000);
@@ -195,6 +204,7 @@ class WsRequestor extends BaseRequestor {
 
   _connect() {
     assert(!this.ws);
+    this._stopPingTimer();
     return new Promise((resolve, reject) => {
       const handshakeTimeout = JAMBONES_WS_HANDSHAKE_TIMEOUT_MS ?
         parseInt(JAMBONES_WS_HANDSHAKE_TIMEOUT_MS) :
@@ -255,10 +265,15 @@ class WsRequestor extends BaseRequestor {
     this.connectInProgress = false;
     this.connections++;
     this.emit('ready', ws);
+
+    if (JAMBONES_WS_PING_INTERVAL_MS > 15000) {
+      this._pingTimer = setInterval(() => this.ws?.ping(), JAMBONES_WS_PING_INTERVAL_MS);
+    }
   }
 
   _onClose(code) {
     this.logger.info(`WsRequestor(${this.id}) - closed from far end ${code}`);
+    this._stopPingTimer();
     if (this.connections > 0 && code !== 1000) {
       this.logger.info({url: this.url}, 'WsRequestor - socket closed unexpectedly from remote side');
       this.emit('socket-closed');
@@ -283,6 +298,7 @@ class WsRequestor extends BaseRequestor {
   _onSocketClosed() {
     this.ws = null;
     this.emit('connection-dropped');
+    this._stopPingTimer();
     if (this.connections > 0 && this.connections < MAX_RECONNECTS && !this.closedGracefully) {
       if (!this._initMsgId) this._clearPendingMessages();
       this.logger.debug(`WsRequestor:_onSocketClosed waiting ${this.backoffMs} to reconnect`);