How to add a route prefix to specific modules using NestJS?

Adding route prefixes to specific modules in NestJS is a straightforward process. This is typically achieved by setting the controllers property within the @Module decorator of the module. To add prefixes to all controllers under a specific module, use the @Controller decorator at the module level and specify the prefix within it. Below are the steps to follow:

1. Import the Module and Controller decorators:

typescript
import { Module, Controller } from '@nestjs/common';

1. Use the @Controller decorator in the module's controller and specify the route prefix:

typescript
@Controller('prefix')
export class YourController {
  // ...
}

In the above code, 'prefix' is the route prefix set for this controller. This means that if your controller has a route decorator like @Get('example'), the final route will be /prefix/example.

1. Of course, you can also set a prefix at the module level to automatically apply it to all controllers registered within the module. First, ensure your module is defined using the @Module decorator, like this:

typescript
@Module({
  controllers: [YourController],
  // ... (other properties like providers, exports, etc.)
})
export class YourModule {}

1. Next, to add route prefixes to all controllers within the entire module, utilize the module class's constructor and the setGlobalPrefix method. For example, you can do this in the main.ts file:

typescript
import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  app.setGlobalPrefix('api');
  await app.listen(3000);
}
bootstrap();

The above code sets a global prefix api for all routes in the application. However, if you only want to set a prefix for a specific module rather than globally, do not use the setGlobalPrefix method.

1. For setting prefixes on specific modules, create a base controller class that uses the @Controller decorator to add the prefix, and have all controllers within the module inherit this base controller.

Example:

typescript
@Controller('modulePrefix')
export class BaseModuleController {}

export class ActualController extends BaseModuleController {
  @Get('example')
  exampleMethod() {
    // ...
  }
}

In this example, ActualController inherits from BaseModuleController, meaning all routes defined in ActualController automatically include the modulePrefix prefix. Therefore, the final route for the exampleMethod method is /modulePrefix/example.

By following these steps, you can effectively add route prefixes to specific modules in your NestJS application to organize and manage your API endpoints.