Docs:

λ yarn add @nestjs/websockets

λ nest g ga events

events.gateway.js

import { SubscribeMessage, WebSocketGateway, WsResponse, WebSocketServer } from '@nestjs/websockets';import { Observable, of } from 'rxjs';import { map } from 'rxjs/operators'const l = console.log@WebSocketGateway()export class EventsGateway {  @WebSocketServer() server;  @SubscribeMessage('events')  onEvent(client: any, payload: any): Observable
    
     
      > | any {    // this.server.emit('resmsg', data);  // io.emit('resmsg', payload)    let { name } = payload;    if (name === 'ajanuw') {      return of({        event: 'events',        data: {          msg: 'hello ajanuw!'        }      })    }    if (name === 'alone') {      return of('hi', '实打实')        .pipe(          map($_ =>            ({              event: 'events', data: {                msg: $_              }            }))        );    }    return of(payload);  }}
     
    

app.module.ts

import { EventsGateway } from './events/events.gateway'@Module({  providers: [EventsGateway],})

客户端

监听进入与离开

import {  SubscribeMessage,  WebSocketGateway,  WsResponse,  WebSocketServer,} from '@nestjs/websockets';import { Observable, of } from 'rxjs';const l = console.log;let num = 0;@WebSocketGateway()export class EventsGateway {  @SubscribeMessage('message')  onEvent(client: any, payload: any): Observable
    
     
      > {    num++    console.log(`有一位用户链接!> ${num}`);    client.on('disconnect', () => {      num--      console.log(`有人离开了...> ${num}`);    })    return of({ event: 'message', data: '233' });  }}