@nmime/nestjs-asyncapi

AsyncAPI module for NestJS. Generate AsyncAPI documentation for event-based services (WebSockets, microservices, Kafka, AMQP, etc.) similar to @nestjs/swagger.

Features

• AsyncAPI 3.0 support (default) - Latest specification
• Full backward compatibility - Supports AsyncAPI 2.x (2.6.0 - 2.0.0) and 1.x (1.2.0 - 1.0.0)
• Decorator-based documentation
• Support for WebSocket gateways and controllers
• Kafka and AMQP bindings support
• HTML documentation generation
• YAML/JSON spec export
• Compatible with NestJS 9, 10, and 11

Demo

• Live Preview
• AsyncAPI Playground

Installation

npm install @nmime/nestjs-asyncapi

To skip Chromium installation (used by AsyncAPI generator for PDF generation):

PUPPETEER_SKIP_CHROMIUM_DOWNLOAD=true npm install @nmime/nestjs-asyncapi

Quick Start

1. Configure AsyncAPI in your bootstrap function

import { NestFactory } from '@nestjs/core';
import { NestExpressApplication } from '@nestjs/platform-express';
import { AsyncApiModule, AsyncApiDocumentBuilder } from '@nmime/nestjs-asyncapi';

async function bootstrap() {
  const app = await NestFactory.create<NestExpressApplication>(AppModule);

  const asyncApiOptions = new AsyncApiDocumentBuilder()
    .setTitle('Feline')
    .setDescription('Feline server description here')
    .setVersion('1.0')
    .setDefaultContentType('application/json')
    .addSecurity('user-password', { type: 'userPassword' })
    .addServer('feline-ws', {
      url: 'ws://localhost:3000',
      protocol: 'socket.io',
    })
    .build();

  const asyncapiDocument = await AsyncApiModule.createDocument(app, asyncApiOptions);
  await AsyncApiModule.setup('/async-api', app, asyncapiDocument);

  await app.listen(3000);
}

bootstrap();

2. Specify AsyncAPI Version (Optional)

By default, the module uses AsyncAPI 3.0.0. You can specify a different version:

const asyncApiOptions = new AsyncApiDocumentBuilder()
  .setAsyncApiVersion('3.0.0')  // Default - AsyncAPI 3.0
  // .setAsyncApiVersion('2.6.0')  // Use AsyncAPI 2.6
  // .setAsyncApiVersion('2.5.0')  // Use AsyncAPI 2.5
  // .setAsyncApiVersion('1.2.0')  // Use AsyncAPI 1.x
  .setTitle('My API')
  .build();

Supported versions: 3.0.0, 2.6.0, 2.5.0, 2.4.0, 2.3.0, 2.2.0, 2.1.0, 2.0.0, 1.2.0, 1.1.0, 1.0.0

3. Add decorators to your controllers/gateways

The module automatically explores Controllers and WebSocketGateway classes. Use @AsyncApi() decorator for other classes that need AsyncAPI documentation.

import { Controller } from '@nestjs/common';
import { ApiProperty } from '@nestjs/swagger';
import { AsyncApiPub, AsyncApiSub } from '@nmime/nestjs-asyncapi';

class CreateFelineDto {
  @ApiProperty()
  name: string;

  @ApiProperty()
  breed: string;
}

@Controller()
class FelineController {
  @AsyncApiPub({
    channel: 'feline/created',
    message: {
      payload: CreateFelineDto,
    },
  })
  async publishFelineCreated() {
    // Publish logic
  }

  @AsyncApiSub({
    channel: 'feline/create',
    message: {
      payload: CreateFelineDto,
    },
  })
  async onCreateFeline() {
    // Subscribe logic
  }
}

Templates

This package includes support for multiple AsyncAPI templates:

Template	Description
@asyncapi/html-template	Static HTML documentation (default)
@asyncapi/nodejs-template	Node.js service using Hermes package
@asyncapi/nodejs-ws-template	Node.js service with WebSockets support

API Endpoints

When you call AsyncApiModule.setup('/async-api', app, document), the following endpoints are available:

Endpoint	Description
/async-api	HTML documentation
/async-api-json	JSON specification
/async-api-yaml	YAML specification

Examples

For detailed examples, check out the sample application.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Credits

This project is a fork of the original nestjs-asyncapi by Ilya Moroz. Thank you for the excellent foundation!

License

MIT - see LICENSE for details.

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