refactor: improve session handling and validation in N8n integration

This commit enhances the N8n integration by refining session management and validation logic. Key changes include:
- Added error handling for session creation failures in the BaseChatbotService.
- Removed unused methods and properties in N8nService and N8nDto to streamline the codebase.
- Updated N8n schema to enforce required fields and improve validation checks.
- Simplified message processing logic to utilize base class methods, enhancing maintainability.

These improvements contribute to a more robust and efficient N8n integration.

Author: gomessguii

src/api/integrations/chatbot/base-chatbot.service.ts

@@ -353,20 +353,25 @@ export abstract class BaseChatbotService<BotType = any, SettingsType = any> {
             ? pushName
             : null;
 
-      session = (
-        await this.createNewSession(
-          {
-            instanceName: instance.instanceName,
-            instanceId: instance.instanceId,
-          },
-          {
-            remoteJid,
-            pushName: pushNameValue,
-            botId: (bot as any).id,
-          },
-          this.getBotType(),
-        )
-      )?.session;
+      const sessionResult = await this.createNewSession(
+        {
+          instanceName: instance.instanceName,
+          instanceId: instance.instanceId,
+        },
+        {
+          remoteJid,
+          pushName: pushNameValue,
+          botId: (bot as any).id,
+        },
+        this.getBotType(),
+      );
+
+      if (!sessionResult || !sessionResult.session) {
+        this.logger.error('Failed to create new session');
+        return;
+      }
+
+      session = sessionResult.session;
     }
 
     // Update session status to opened

src/api/integrations/chatbot/n8n/controllers/n8n.controller.ts

@@ -110,58 +110,6 @@ export class N8nController extends BaseChatbotController<N8nModel, N8nDto> {
     return super.createBot(instance, data);
   }
 
-  public async findBot(instance: InstanceDto) {
-    if (!this.integrationEnabled) throw new BadRequestException('N8n is disabled');
-
-    const instanceId = await this.prismaRepository.instance
-      .findFirst({
-        where: {
-          name: instance.instanceName,
-        },
-      })
-      .then((instance) => instance.id);
-
-    const bots = await this.botRepository.findMany({
-      where: {
-        instanceId: instanceId,
-      },
-    });
-
-    if (!bots.length) {
-      return null;
-    }
-
-    return bots;
-  }
-
-  public async fetchBot(instance: InstanceDto, botId: string) {
-    if (!this.integrationEnabled) throw new BadRequestException('N8n is disabled');
-
-    const instanceId = await this.prismaRepository.instance
-      .findFirst({
-        where: {
-          name: instance.instanceName,
-        },
-      })
-      .then((instance) => instance.id);
-
-    const bot = await this.botRepository.findFirst({
-      where: {
-        id: botId,
-      },
-    });
-
-    if (!bot) {
-      throw new Error('N8n not found');
-    }
-
-    if (bot.instanceId !== instanceId) {
-      throw new Error('N8n not found');
-    }
-
-    return bot;
-  }
-
   // Process N8n-specific bot logic
   protected async processBot(
     instance: any,
@@ -173,6 +121,7 @@ export class N8nController extends BaseChatbotController<N8nModel, N8nDto> {
     pushName?: string,
     msg?: any,
   ) {
-    this.n8nService.process(instance, remoteJid, bot, session, settings, content, pushName, msg);
+    // Use the base class pattern instead of calling n8nService.process directly
+    await this.n8nService.process(instance, remoteJid, bot, session, settings, content, pushName, msg);
   }
 }

src/api/integrations/chatbot/n8n/dto/n8n.dto.ts

@@ -1,32 +1,14 @@
-import { TriggerOperator, TriggerType } from '@prisma/client';
-
 import { BaseChatbotDto, BaseChatbotSettingDto } from '../../base-chatbot.dto';
 
 export class N8nDto extends BaseChatbotDto {
   // N8n specific fields
   webhookUrl?: string;
   basicAuthUser?: string;
   basicAuthPass?: string;
-
-  // Advanced bot properties (copied from DifyDto style)
-  triggerType: TriggerType;
-  triggerOperator?: TriggerOperator;
-  triggerValue?: string;
-  expire?: number;
-  keywordFinish?: string;
-  delayMessage?: number;
-  unknownMessage?: string;
-  listeningFromMe?: boolean;
-  stopBotFromMe?: boolean;
-  keepOpen?: boolean;
-  debounceTime?: number;
-  ignoreJids?: string[];
-  splitMessages?: boolean;
-  timePerChar?: number;
 }
 
 export class N8nSettingDto extends BaseChatbotSettingDto {
-  // N8n specific fields
+  // N8n has no specific fields
 }
 
 export class N8nMessageDto {