added a dedicated error handler service

libs/common/src/auth/services/auth.service.ts

@@ -6,6 +6,7 @@ import { UserRepository } from '../../../../common/src/modules/user/repositories
 import { UserSessionRepository } from '../../../../common/src/modules/session/repositories/session.repository';
 import { UserSessionEntity } from '../../../../common/src/modules/session/entities';
 import { ConfigService } from '@nestjs/config';
+import { OAuth2Client } from 'google-auth-library';
 
 @Injectable()
 export class AuthService {

libs/common/src/common.module.ts

@@ -6,10 +6,16 @@ import { AuthModule } from './auth/auth.module';
 import { ConfigModule } from '@nestjs/config';
 import config from './config';
 import { EmailService } from './util/email.service';
-
+import { ErrorMessageService } from 'src/error-message/error-message.service';
 @Module({
-  providers: [CommonService, EmailService],
+  providers: [CommonService, EmailService, ErrorMessageService],
-  exports: [CommonService, HelperModule, AuthModule, EmailService],
+  exports: [
+    CommonService,
+    HelperModule,
+    AuthModule,
+    EmailService,
+    ErrorMessageService,
+  ],
   imports: [
     ConfigModule.forRoot({
       load: config,

src/common/filters/http-exception/http-exception.filter.spec.ts

@@ -0,0 +1,7 @@
+import { HttpExceptionFilter } from './http-exception.filter';
+
+describe('HttpExceptionFilter', () => {
+  it('should be defined', () => {
+    expect(new HttpExceptionFilter()).toBeDefined();
+  });
+});

src/common/filters/http-exception/http-exception.filter.ts

@@ -0,0 +1,38 @@
+import {
+  ExceptionFilter,
+  Catch,
+  ArgumentsHost,
+  HttpException,
+  HttpStatus,
+} from '@nestjs/common';
+import { Response } from 'express';
+
+@Catch()
+export class HttpExceptionFilter implements ExceptionFilter {
+  catch(exception: unknown, host: ArgumentsHost) {
+    const ctx = host.switchToHttp();
+    const response = ctx.getResponse<Response>();
+    const request = ctx.getRequest<Request>();
+    const status =
+      exception instanceof HttpException
+        ? exception.getStatus()
+        : HttpStatus.INTERNAL_SERVER_ERROR;
+
+    const message =
+      exception instanceof HttpException
+        ? exception.getResponse()
+        : 'Internal server error';
+
+    const errorResponse = {
+      statusCode: status,
+      timestamp: new Date().toISOString(),
+      path: request.url,
+      error: message,
+    };
+
+    // Optionally log the exception
+    console.error(`Error occurred:`, exception);
+
+    response.status(status).json(errorResponse);
+  }
+}

src/error-message/error-message.service.spec.ts

@@ -0,0 +1,18 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { ErrorMessageService } from './error-message.service';
+
+describe('ErrorMessageService', () => {
+  let service: ErrorMessageService;
+
+  beforeEach(async () => {
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [ErrorMessageService],
+    }).compile();
+
+    service = module.get<ErrorMessageService>(ErrorMessageService);
+  });
+
+  it('should be defined', () => {
+    expect(service).toBeDefined();
+  });
+});

src/error-message/error-message.service.ts

@@ -0,0 +1,40 @@
+// src/common/services/error-message.service.ts
+import { Injectable } from '@nestjs/common';
+type ErrorMessageKey = keyof typeof ErrorMessageService.prototype.messages;
+
+@Injectable()
+export class ErrorMessageService {
+  public readonly messages = {
+    NOT_FOUND: '{entity} not found', // Single key for "not found" errors
+    INVALID_MINUTES: 'Invalid minutes value',
+    INVALID_TIME_FORMAT: 'Invalid time format',
+    USER_NOT_FOUND: '{entity} not found', // Can reuse NOT_FOUND if desired
+    INTERNAL_SERVER_ERROR: 'Internal server error',
+    ERROR_ADDING_TEMP_PASSWORD:
+      'Error adding {type} temporary password from Tuya',
+    INVALID_UUID: 'Invalid {entity} UUID',
+    USER_ALREADY_BELONGS: 'This user already belongs to this {entity}',
+    USER_HAS_NO_ENTITIES: 'This user has no {entity}',
+    DEVICE_OPERATION_FAILED: 'All device operations failed',
+    REQUEST_FAILED: 'Error processing {operation} request',
+    COOLDOWN_ERROR:
+      'Please wait {time} more seconds before requesting a new OTP.',
+  };
+
+  getMessage(
+    key: ErrorMessageKey,
+    params?: Record<string, string | number>,
+  ): string {
+    let message = this.messages[key] || 'Unknown error';
+
+    // Replace placeholders with provided params
+    if (params) {
+      Object.keys(params).forEach((param) => {
+        const regex = new RegExp(`{${param}}`, 'g');
+        message = message.replace(regex, params[param].toString());
+      });
+    }
+
+    return message;
+  }
+}

src/main.ts

@@ -6,6 +6,7 @@ import { setupSwaggerAuthentication } from '../libs/common/src/util/user-auth.sw
 import { ValidationPipe } from '@nestjs/common';
 import { json, urlencoded } from 'body-parser';
 import { SeederService } from '@app/common/seed/services/seeder.service';
+import { HttpExceptionFilter } from './common/filters/http-exception/http-exception.filter';
 
 async function bootstrap() {
   const app = await NestFactory.create(AppModule);
@@ -15,6 +16,7 @@ async function bootstrap() {
   // Set the body parser limit to 1 MB
   app.use(json({ limit: '1mb' }));
   app.use(urlencoded({ limit: '1mb', extended: true }));
+  app.useGlobalFilters(new HttpExceptionFilter());
 
   app.use(
     rateLimit({

src/region/region.module.ts

@@ -3,9 +3,10 @@ import { RegionService } from './services/region.service';
 import { RegionController } from './controllers/region.controller';
 import { ConfigModule } from '@nestjs/config';
 import { RegionRepository } from '@app/common/modules/region/repositories';
+import { CommonModule } from '@app/common';
 
 @Module({
-  imports: [ConfigModule],
+  imports: [ConfigModule, CommonModule],
   controllers: [RegionController],
   providers: [RegionService, RegionRepository],
   exports: [RegionService],

src/region/services/region.service.ts

@@ -2,23 +2,33 @@ import {
   BadRequestException,
   HttpException,
   HttpStatus,
+  Inject,
   Injectable,
 } from '@nestjs/common';
 import { RegionRepository } from '@app/common/modules/region/repositories';
+import { ErrorMessageService } from 'src/error-message/error-message.service';
 
 @Injectable()
 export class RegionService {
-  constructor(private readonly regionRepository: RegionRepository) {}
+  constructor(
+    private readonly regionRepository: RegionRepository,
+    @Inject(ErrorMessageService)
+    private readonly errorMessageService: ErrorMessageService,
+  ) {}
   async getAllRegions() {
     try {
       const regions = await this.regionRepository.find();
-
       return regions;
     } catch (err) {
       if (err instanceof BadRequestException) {
         throw err; // Re-throw BadRequestException
       } else {
-        throw new HttpException('Regions found', HttpStatus.NOT_FOUND);
+        throw new HttpException(
+          this.errorMessageService.getMessage('NOT_FOUND', {
+            entity: 'Regions',
+          }),
+          HttpStatus.NOT_FOUND,
+        );
       }
     }
   }