Fix redis connection issues

src/app.ts

@@ -32,14 +32,31 @@ app.use(cookieParser());
 if (getEnv() === Env.prod) {
     const redisClient = createClient({
         url: config.get('redis.url'),
+        // Periodically PING so a half-open connection (e.g. after the Redis
+        // server restarts behind a stable ClusterIP) is detected and a
+        // reconnect is triggered. Without this, node-redis keeps queueing
+        // commands on the dead socket and express-session never gets a reply,
+        // so every session-writing request (e.g. /auth-oidc) hangs forever
+        // until the pod is restarted.
+        pingInterval: 10000,
+        socket: {
+            keepAlive: 5000,
+            connectTimeout: 10000,
+            // Keep retrying with capped backoff instead of giving up.
+            reconnectStrategy: (retries) => Math.min(retries * 100, 3000),
+        },
     });
 
+    // node-redis throws (and can crash the process) if an 'error' is emitted
+    // with no listener; log it and let the reconnect strategy recover.
+    redisClient.on('error', (err) => logger.error(`Redis session store error: ${err}`));
+
     sessionStore = new RedisStore({
         prefix: 'walias:',
         client: redisClient,
     });
 
-    redisClient.connect().catch(console.error);
+    redisClient.connect().catch((err) => logger.error(`Redis initial connect failed: ${err}`));
 }
 
 app.use(