From 21796e6283bce1c66741ed6e023ce9e21ac9358b Mon Sep 17 00:00:00 2001
From: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Date: Mon, 4 May 2026 11:20:32 +0000
Subject: [PATCH] fix(instance): handle stale DB records after restart +
 prevent Redis spam

- Instance guard: when creating an instance, detect if the name exists
  in the database but not in memory (stale after server restart). Auto
  cleanup the stale DB record so re-creation succeeds instead of
  returning 403 'name already in use' followed by 404 on all operations.

- Redis client: skip connection when CACHE_REDIS_ENABLED is false or
  CACHE_REDIS_URI is empty. Previously the client would attempt to
  connect regardless, flooding logs with 'redis disconnected' errors
  every second when no Redis server is available.

- .env.example: change defaults to CACHE_REDIS_ENABLED=false and
  CACHE_LOCAL_ENABLED=true so deployments without Redis work out of
  the box (Dockerfile copies .env.example as .env).

Co-Authored-By: Chris Tolu <eksucampusmarketplace@gmail.com>
---
 .env.example                     |  8 +++++---
 src/api/guards/instance.guard.ts | 29 ++++++++++++++++++++++++++++-
 src/cache/rediscache.client.ts   |  9 +++++++++
 3 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/.env.example b/.env.example
index 73a3b40d35..df4cadb7c6 100644
--- a/.env.example
+++ b/.env.example
@@ -346,15 +346,17 @@ EVOAI_ENABLED=false
 
 # Cache - Environment variables
 # Redis Cache enabled
-CACHE_REDIS_ENABLED=true
+# Set to true only if you have a Redis server available.
+# When false (or URI is empty), the app uses local cache instead.
+CACHE_REDIS_ENABLED=false
 CACHE_REDIS_URI=redis://localhost:6379/6
 CACHE_REDIS_TTL=604800
 # Prefix serves to differentiate data from one installation to another that are using the same redis
 CACHE_REDIS_PREFIX_KEY=evolution
 # Enabling this variable will save the connection information in Redis and not in the database.
 CACHE_REDIS_SAVE_INSTANCES=false
-# Local Cache enabled
-CACHE_LOCAL_ENABLED=false
+# Local Cache enabled (recommended when Redis is not available)
+CACHE_LOCAL_ENABLED=true
 
 # Amazon S3 - Environment variables
 S3_ENABLED=false
diff --git a/src/api/guards/instance.guard.ts b/src/api/guards/instance.guard.ts
index e692f3622e..b74eaf77ab 100644
--- a/src/api/guards/instance.guard.ts
+++ b/src/api/guards/instance.guard.ts
@@ -1,9 +1,12 @@
 import { InstanceDto } from '@api/dto/instance.dto';
 import { cache, prismaRepository, waMonitor } from '@api/server.module';
 import { CacheConf, configService } from '@config/env.config';
+import { Logger } from '@config/logger.config';
 import { BadRequestException, ForbiddenException, InternalServerErrorException, NotFoundException } from '@exceptions';
 import { NextFunction, Request, Response } from 'express';
 
+const logger = new Logger('InstanceGuard');
+
 async function getInstance(instanceName: string) {
   try {
     const cacheConf = configService.get<CacheConf>('CACHE');
@@ -22,6 +25,23 @@ async function getInstance(instanceName: string) {
   }
 }
 
+async function isInstanceOnlyInDatabase(instanceName: string): Promise<boolean> {
+  const inMemory = !!waMonitor.waInstances[instanceName];
+  if (inMemory) return false;
+
+  const dbRecords = await prismaRepository.instance.findMany({ where: { name: instanceName } });
+  return dbRecords.length > 0;
+}
+
+async function removeStaleInstance(instanceName: string): Promise<void> {
+  try {
+    await waMonitor.cleaningStoreData(instanceName);
+    logger.warn(`Removed stale database record for instance "${instanceName}" (not loaded in memory)`);
+  } catch (error) {
+    logger.error(`Failed to remove stale instance "${instanceName}": ${error}`);
+  }
+}
+
 export async function instanceExistsGuard(req: Request, _: Response, next: NextFunction) {
   if (req.originalUrl.includes('/instance/create') || req.originalUrl.includes('/instance/fetchInstances')) {
     return next();
@@ -43,7 +63,14 @@ export async function instanceLoggedGuard(req: Request, _: Response, next: NextF
   if (req.originalUrl.includes('/instance/create')) {
     const instance = req.body as InstanceDto;
     if (await getInstance(instance.instanceName)) {
-      throw new ForbiddenException(`This name "${instance.instanceName}" is already in use.`);
+      if (await isInstanceOnlyInDatabase(instance.instanceName)) {
+        logger.warn(
+          `Instance "${instance.instanceName}" exists in database but not in memory (stale after restart). Cleaning up for re-creation.`,
+        );
+        await removeStaleInstance(instance.instanceName);
+      } else {
+        throw new ForbiddenException(`This name "${instance.instanceName}" is already in use.`);
+      }
     }
 
     if (waMonitor.waInstances[instance.instanceName]) {
diff --git a/src/cache/rediscache.client.ts b/src/cache/rediscache.client.ts
index 45a0321ff9..d3505ee468 100644
--- a/src/cache/rediscache.client.ts
+++ b/src/cache/rediscache.client.ts
@@ -13,6 +13,15 @@ class Redis {
   }
 
   getConnection(): RedisClientType {
+    if (!this.conf?.ENABLED) {
+      return null;
+    }
+
+    if (!this.conf?.URI) {
+      this.logger.warn('CACHE_REDIS_ENABLED is true but CACHE_REDIS_URI is empty — skipping Redis connection');
+      return null;
+    }
+
     if (this.connected) {
       return this.client;
     } else {