feat(server): add keep-alive ping to prevent PaaS services from sleeping

.env.example

@@ -45,6 +45,13 @@ LOG_BAILEYS=error
 # Set the maximum number of listeners that can be registered for an event
 EVENT_EMITTER_MAX_LISTENERS=50
 
+# Keep-alive - Periodically ping URLs to prevent PaaS services (Render, etc.) from sleeping.
+# KEEP_ALIVE_URLS accepts a comma-separated list of external URLs to ping (e.g. your BotWave URL).
+# SERVER_URL is always pinged automatically when keep-alive is enabled.
+KEEP_ALIVE_ENABLED=false
+KEEP_ALIVE_INTERVAL=10
+KEEP_ALIVE_URLS=
+
 # Determine how long the instance should be deleted from memory in case of no connection.
 # Default time: 5 minutes
 # If you don't even want an expiration, enter the value false

src/config/env.config.ts

@@ -389,6 +389,12 @@ export type EventEmitter = {
   MAX_LISTENERS: number;
 };
 
+export type KeepAlive = {
+  ENABLED: boolean;
+  INTERVAL: number;
+  URLS: string[];
+};
+
 export type Production = boolean;
 
 export interface Env {
@@ -428,6 +434,7 @@ export interface Env {
   FACEBOOK: Facebook;
   SENTRY: Sentry;
   EVENT_EMITTER: EventEmitter;
+  KEEP_ALIVE: KeepAlive;
   PRODUCTION?: Production;
 }
 
@@ -903,6 +910,14 @@ export class ConfigService {
       EVENT_EMITTER: {
         MAX_LISTENERS: Number.parseInt(process.env?.EVENT_EMITTER_MAX_LISTENERS) || 50,
       },
+      KEEP_ALIVE: {
+        ENABLED: process.env?.KEEP_ALIVE_ENABLED === 'true',
+        INTERVAL: Number.parseInt(process.env?.KEEP_ALIVE_INTERVAL) || 10,
+        URLS:
+          process.env?.KEEP_ALIVE_URLS?.split(',')
+            .map((url) => url.trim())
+            .filter(Boolean) || [],
+      },
     };
   }
 }

src/main.ts

@@ -11,6 +11,7 @@ import {
   configService,
   Cors,
   HttpServer,
+  KeepAlive,
   ProviderSession,
   Sentry as SentryConfig,
   Webhook,
@@ -159,6 +160,29 @@ async function bootstrap() {
 
   server.listen(httpServer.PORT, () => logger.log(httpServer.TYPE.toUpperCase() + ' - ON: ' + httpServer.PORT));
 
+  const keepAlive = configService.get<KeepAlive>('KEEP_ALIVE');
+  if (keepAlive.ENABLED) {
+    const intervalMs = keepAlive.INTERVAL * 60 * 1000;
+    const urls = [...keepAlive.URLS];
+
+    if (httpServer.URL) {
+      urls.unshift(httpServer.URL);
+    }
+
+    if (urls.length > 0) {
+      logger.info(`Keep-alive pinging ${urls.length} URL(s) every ${keepAlive.INTERVAL}m`);
+
+      setInterval(() => {
+        for (const url of urls) {
+          axios
+            .get(url, { timeout: 15000 })
+            .then(() => logger.verbose(`Keep-alive OK: ${url}`))
+            .catch((err) => logger.warn(`Keep-alive failed: ${url} - ${err.message}`));
+        }
+      }, intervalMs);
+    }
+  }
+
   initWA().catch((error) => {
     logger.error('Error loading instances: ' + error);
   });