如何搭建一个 websocket-编程知识

如何搭建一个 websocket

环境:

NodeJs
socket.io 4.7.2

安装依赖

yarn add socket.io

创建服务器

引入文件

特别注意: 涉及到 colors 的代码，请采取 console.log() 打印

// 基础老三样
import http from "http";
import fs from "fs";
import { Server } from "socket.io";// 下面2个是我本地开发的,你们可能没有
import colors from "colors-console";
import constant_color from "./colors.js";

createServer

请在当前目录下创建 index.html 文件。【客户端需要连接 socket.io】

<script src="/socket.io/socket.io.js"></script><script>constsocket = io();
</script>

服务端代码：

const server = http.createServer((req, res) => {fs.readFile("./index.html", "utf-8", (err, data) => {if (err) {res.writeHead(500, "utf-8", e);res.end();}res.writeHead(200, {"Content-Type": "text/html"});res.end(data, "utf-8");});
});

websocket

简单判断客户端是否连接，断开。

const io = new Server(server);io.on("connection", socket => {console.succ("User connected.");// 用户断开连接socket.on("disconnect", () => {console.err("User disconnected.");})
});server.listen(3000, "127.0.0.1");

启动服务器

yarn app

在这里插入图片描述

附录

再次提醒：请去除所有 console.err console.succ colors 等有关颜色内容
在这里插入图片描述
项目结构：【它们都是同级目录，最顶层】

D:.
│  app.js
│  colors.js
│  index.html
│  package.json
│  yarn.lock
│
└─node_modules

app.js 代码：

import http from "http";
import fs from "fs";
import { Server } from "socket.io";
import colors from "colors-console";
import constant_color from "./colors.js";// 重写 console.err 
console.err = (...msg) => {let str = "";for (let i = 0; i < msg.length; i++) {str += msg[i] + " ";}console.log(colors(constant_color.red, str));
}// 定义 console.succ
console.succ = (...msg) => {let str = "";for (let i = 0; i < msg.length; i++) {str += msg[i] + " ";}console.log(colors(constant_color.green, str));
}const server = http.createServer((req, res) => {fs.readFile("./index.html", "utf-8", (err, data) => {if (err) {res.writeHead(500, "utf-8", e);res.end();}res.writeHead(200, {"Content-Type": "text/html"});res.end(data, "utf-8");});
});const io = new Server(server);io.on("connection", socket => {console.succ("User connected.");// 用户断开连接socket.on("disconnect", () => {console.err("User disconnected.");})
});server.listen(3000, "127.0.0.1");console.log("Server running at \x1B[36m\x1B[4mhttp://127.0.0.1:3000\x1B[0m");

index.html 代码：

<!DOCTYPE html>
<html lang="zh-CN"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><script src="/socket.io/socket.io.js"></script>
</head><body><h1>Hello Friend! 😀</h1><script>const socket = io();</script>
</body></html>