Common Library

Common shared library between microservices with common definitions like errors types, filters, transformers, base entities, services and utilities.

Bootstrapping

• configureMicroservice: Function that configures a nest application with the transformers, filters and logger services.

Common

• BaseEntity: It is an abstract class that works as base type for all the entities, this base entity depend of typeorm.

• BusinessError: It is a base class for all custom errors, it is required that custom errors inherit from this class so that they could be interpreted and formatted by our error filters.

Filter

• CustomExceptionFilter: This is a nestjs filter that handle custom error responses.

Interceptor

• TransformInterceptor: This is a nestjs interceptor that apples a common controller response for all requests.

Modules

• SharedModule: This is a shared module that exports some shared services within the application like the logger service, it is recommended to import this function in the main module (ex. AppModule).
• JwtAuthModule: Reusable module that adds JWT validation using Passport strategy jwt. Useful to protect microservices with shared auth logic. Exports strategy, PassportModule, and JwtModule.
  See JWT Auth Module section for detailed configuration and usage.

Requirements

• NodeJs v16 or greater
• NestJs framework v.9 or equivalent

Usage

1. Install the library in you project

   npm install incident-managment-commons

2. Import IncidentManagementSharedModule in the main module of your application.

   import { Module } from '@nestjs/common';
   
   import { IncidentManagementSharedModule } from 'incident-managment-commons';
   
   import { AppController } from './app.controller';
   
   @Module({
     imports: [
       IncidentManagementSharedModule,
     ],
     controllers: [AppController],
   })
   export class AppModule {}
   

3. Import and run the configureMicroservice function within your bootstrap application function

   import { ConfigService } from '@nestjs/config';
   import { NestFactory } from '@nestjs/core';
   
   import { configureMicroservice } from 'incident-managment-commons';
   
   import { AppModule } from './app.module';
   
   async function bootstrap() {
     const app = await NestFactory.create(AppModule);
   
     configureMicroservice(app, {
       title: 'Example Service',
       description: 'API for example service',
       version: '1.0',
       basePath: 'example',
     });
   
     const configService = app.select(AppModule).get(ConfigService);
   
     const port = configService.get('PORT') || 3001;
   
     await app.listen(port);
   }
   bootstrap();

JWT Auth Module

1. Add the following environment variables to your .env file:

     JWT_SECRET=your-jwt-secret

2. Import JwtAuthModule in the main module of your application:

   import { Module } from '@nestjs/common';
   import { JwtAuthModule } from 'incident-managment-commons';
   
   @Module({
     imports: [
       JwtAuthModule,
     ],
   })
   export class AppModule {}

3. The JwtAuthGuard is typically applied globally using app.useGlobalGuards(...) during application bootstrap, so you don't need to use @UseGuards(JwtAuthGuard) manually on each controller.

4. If you want to make a route public (no authentication required), use the @Public() decorator:

   import { Controller, Get } from '@nestjs/common';
   import { Public } from 'incident-managment-commons';
   
   @Controller('healthz')
   export class HealthController {
     @Get()
     @Public()
     getHealthStatus() {
       return { status: 'ok' };
     }
   }