NestJS Hybrid App - microservice & app port conflict - EADDRINUSE address already in use-CodePudding

I have a basic nest app with following code


async function bootstrap(port: number) {
    const app = await NestFactory.create(AppModule);
    app.connectMicroservice<MicroserviceOptions>({
        transport: Transport.TCP,
        options: {
            port,
        },
    });
    await app.startAllMicroservices();
    app.enableCors();
    await app.listen(port, () => {
        logger.log(`HTTP Server listening at ${port}`);
    });
}

const port =  process.env?.PORT || 3001;
bootstrap(port);

This code throws error

Error: listen EADDRINUSE: address already in use :::3000

I have basic understanding what is happening, I am using same port for microservice as well as app.listen(). Even though they are pointing to same port, This should work according to nestjs doc, and this answer https://stackoverflow.com/a/64959626/550907

But I am getting the port already used error in my ubuntu server. When I run it in my local server it works. This makes me thinking perhaps something differently setup in the server.

Wondering if anyone else had the same issue and know how to solve this?

My Observation:

When I comment out the line await app.startAllMicroservices(); the application runs without an error.

So, Microservice starts on the given port

[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [NestMicroservice] Nest microservice successfully started  8ms

after that when app tries to start it fails.

Update 2

When I said it was running in my local machine. I didn't mention i was using docker in my local environment.

So, when I am running this in Docker (alpine node) it works, but not when running directly in ubuntu. I've tried it without docker in my local and it didn't work.

Update

Is port 3000 free?

Yes lsof -i tcp:3000 show empty output nothing running on the port.

Did you try changing port?

Yes, it didn't help

Did you try running it using npm instead of yarn?

Yes, it didn't help

Can you provide full console output?

Here is the console when I try to run in dev mode (yarn start creates same issue).

[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [NestFactory] Starting Nest application...
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] PrismaModule dependencies initialized  46ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] ClientsModule dependencies initialized  1ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] DiscoveryModule dependencies initialized  1ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] ConfigHostModule dependencies initialized  0ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] AppModule dependencies initialized  1ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] ConfigModule dependencies initialized  0ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] ScheduleModule dependencies initialized  0ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] ConfigModule dependencies initialized  1ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] CacheModule dependencies initialized  15ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [InstanceLoader] CongestionsModule dependencies initialized  6ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [NestMicroservice] Nest microservice successfully started  8ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [RoutesResolver] AppController {/}:  48ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [RouterExplorer] Mapped {/, GET} route  2ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [RoutesResolver] CongestionsController {/congestions}:  0ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [RouterExplorer] Mapped {/congestions, GET} route  1ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [RouterExplorer] Mapped {/congestions/clinic/:id, GET} route  0ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM     LOG [NestApplication] Nest application successfully started  162ms
[Nest] 2544  - 05/24/2022, 2:07:03 AM   ERROR [NestApplication] Error: listen EADDRINUSE: address already in use :::3000  1ms
Error: listen EADDRINUSE: address already in use :::3000
    at Server.setupListenHandle [as _listen2] (node:net:1372:16)
    at listenInCluster (node:net:1420:12)
    at Server.listen (node:net:1508:7)
    at ExpressAdapter.listen (/var/www/analyzer/node_modules/@nestjs/platform-express/adapters/express-adapter.js:63:32)
    at /var/www/analyzer/node_modules/@nestjs/core/nest-application.js:167:30
    at new Promise (<anonymous>)
    at NestApplication.listen (/var/www/analyzer/node_modules/@nestjs/core/nest-application.js:156:16)
    at bootstrap (/var/www/analyzer/src/main.ts:20:2)

CodePudding user response：

To determine what is using that port:

lsof -i tcp:3000

CodePudding user response：

You have two apps listening on port 3000

The microservice you connect to your app
The app itself

You can use a different port for the microservice. As in the snippet below:

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  app.connectMicroservice<MicroserviceOptions>({
    transport: Transport.TCP,
    options: {
      port: 8877
    }
  })
  
  app.startAllMicroservices();
  app.listen(3000);
}
bootstrap();