NestJS Integration

OPRA is designed to work alongside NestJS. Rather than replacing NestJS's module system, dependency injection, or lifecycle hooks, OPRA plugs into them — your controllers are registered as standard NestJS controllers, your services are injected as usual, and OPRA adds the contract layer on top.

tip

NestJS is the recommended way to build OPRA applications.

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How it fits together

NestJS AppModule
└── OpraHttpModule.forRoot(...)
    ├── types: [Customer, Order, ...]      ← data model types
    ├── controllers: [CustomersController] ← OPRA controllers (NestJS controllers)
    └── providers: [CustomersService]      ← injected as usual

OPRA provides a dedicated module for each supported transport:

Package	Transport
@opra/nestjs-http	HTTP (Express)
@opra/nestjs-socketio	Socket.IO
@opra/nestjs-kafka	Kafka
@opra/nestjs-rabbitmq	RabbitMQ

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Setup

import { Module } from '@nestjs/common';
import { OpraHttpModule } from '@opra/nestjs-http';
import { CustomersController } from './customers/customers.controller.js';
import { CustomersService } from './customers/customers.service.js';
import * as models from './models/index.js';

@Module({
  imports: [
    OpraHttpModule.forRoot({
      name: 'MyApi',
      info: { title: 'My API', version: '1.0' },
      types: Object.values(models),
      controllers: [CustomersController],
      providers: [CustomersService],
    }),
  ],
})
export class AppModule {}

Controllers declared in controllers are standard NestJS controllers — they receive injected dependencies through the constructor in the normal way:

@HttpController({ path: 'customers' })
export class CustomersController {
  constructor(private readonly service: CustomersService) {}

  @HttpOperation.Entity.FindMany(Customer)
  async findMany(ctx: HttpContext) {
    const { options } = await MongoAdapter.parseRequest(ctx);
    return this.service.for(ctx).findMany(options);
  }
}

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What NestJS brings, what OPRA adds

NestJS	OPRA
Module system & DI container	End-to-end request validation & encoding
Guards, interceptors, pipes	Data model type system
Lifecycle hooks	Multi-protocol transport (HTTP, MQ, WS)
Application structure	API schema generation & publication

Neither framework interferes with the other. NestJS guards run before OPRA's request parsing; NestJS interceptors wrap the full OPRA execution. You can use both freely.

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→ NestJS Setup · HTTP Module · Kafka Module · RabbitMQ Module · Socket.IO Module