nestjs

NestJS Microservices Development

Project Structure

This project uses NestJS for three microservices:

• apps/auth - Authentication (JWT, Passport)
• apps/order - Order management (integrates with Temporal)
• apps/product - Product catalog

Shared modules are in packages/core.

Creating a New Module

1. Create Module File

// feature/feature.module.ts
import { Module } from '@nestjs/common';
import { FeatureController } from './feature.controller';
import { FeatureService } from './feature.service';

@Module({
  controllers: [FeatureController],
  providers: [FeatureService],
  exports: [FeatureService],
})
export class FeatureModule {}

2. Create Service with Repository Pattern

// feature/feature.service.ts
import { Injectable } from '@nestjs/common';
import { PrismaService } from '@projectx/db';

@Injectable()
export class FeatureService {
  constructor(private readonly prisma: PrismaService) {}

  async findAll() {
    return this.prisma.feature.findMany();
  }

  async findOne(id: string) {
    return this.prisma.feature.findUnique({ where: { id } });
  }

  async create(data: CreateFeatureDto) {
    return this.prisma.feature.create({ data });
  }
}

3. Create Controller with Swagger

// feature/feature.controller.ts
import { Controller, Get, Post, Body, Param } from '@nestjs/common';
import { ApiTags, ApiOperation, ApiResponse } from '@nestjs/swagger';
import { FeatureService } from './feature.service';

@ApiTags('features')
@Controller('features')
export class FeatureController {
  constructor(private readonly featureService: FeatureService) {}

  @Get()
  @ApiOperation({ summary: 'Get all features' })
  @ApiResponse({ status: 200, description: 'Returns all features' })
  findAll() {
    return this.featureService.findAll();
  }

  @Get(':id')
  @ApiOperation({ summary: 'Get feature by ID' })
  findOne(@Param('id') id: string) {
    return this.featureService.findOne(id);
  }

  @Post()
  @ApiOperation({ summary: 'Create a feature' })
  create(@Body() createFeatureDto: CreateFeatureDto) {
    return this.featureService.create(createFeatureDto);
  }
}