my-chat-room/apps/chat-room/src/app/app.module.ts

import { HttpClientModule } from '@angular/common/http';
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { SocketIoModule, SocketIoConfig } from 'ngx-socket-io';

import { AppComponent } from './app.component';
import { FormsModule } from '@angular/forms';

const config: SocketIoConfig = {
  url: ':4001',
  options: {},
};

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    HttpClientModule,
    FormsModule,
    SocketIoModule.forRoot(config),
  ],
  providers: [],
  bootstrap: [AppComponent],
})
export class AppModule {}