request: expose httpServer to app context

I’m submitting a…

[ ] Regression 
[ ] Bug report
[x] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead post your question on Stack Overflow.

I want to be able to access the httpServer from the application context. Specifically, in my case I want to simply register a graphql subscriptions server (I saw the example, but it’s too complicated and creates a new server instead of reusing the existing one)

class MyModule implements NestModule {

// ...

configure(consumer: MiddlewaresConsumer) {
  // get schema

    new SubscriptionServer({
      execute,
      subscribe,
      schema
    }, {
      // server: appHttpServer, // ?? how do I get reference to the app server?
      path: '/subscriptions',
    });

[kamilmysliwiec]

You can inject HTTP server reference using HTTP_SERVER_REF token. The reference is an HTTP adapter currently used by the application. Each adapter implements HttpServer interface:

@Inject(HTTP_SERVER_REF) httpServerRef: HttpServer

The HTTP_SERVER_REF is exported from @nestjs/core while HttpServer interface from @nestjs/common. Also, this instance exposes getHttpServer() method that allows picking up the underlying object (express instance by default).

[Melse]

@blissi try this.httpServerRef.getHttpServer()

@Injectable()
export class SubscriptionsService implements OnModuleDestroy {
    private subscriptionServer: SubscriptionServer;

    constructor(
        @Inject(HTTP_SERVER_REF) private readonly httpServerRef: HttpServer,
    ) {}

    createSubscriptionServer(
        schema: any,
        options: ServerOptions = {},
        socketOptions: WebSocket.ServerOptions = {},
    ) {
        this.subscriptionServer = new SubscriptionServer(
            {
                execute,
                subscribe,
                schema,
                ...options,
            },
            {
                server: this.httpServerRef.getHttpServer(),
                path: '/subscriptions',
                ...socketOptions,
            },
        );
    }

    onModuleDestroy() {
        this.subscriptionServer.close();
    }
}