Middleware

Nestjs middleware is equivalent to Express middleware

Custom middleware is implemented either in either a function, or in a class with an @Injectable() decorator.

• The class should implement the NestMiddleware interface, while the function does not have any special requirements.

Middleware fully supports dependency injection.

We set up middleware using the configure() method of the module class.

• Modules that include middleware have to implement the NestModule interface.

@Module({
  imports: [CatsModule],
})
export class AppModule implements NestModule {
  configure(consumer: MiddlewareConsumer) {
    consumer
      .apply(LoggerMiddleware)
      .forRoutes('cats');
  }
}

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Backlinks

• Nestjs