利用node启动简单的静态http服务

http模块创建的是http服务
net模块创建的是tcp服务

1. 简单的

const http = require('http');
const fs = require('fs'); 
const path = require('path');
//静态资源的路径
const staticUrl = __dirname;
const server = http.createServer(function(req,res){
    //req,res均为对象，req是http.IncomingMessage的一个实例，res是http.ServerResponse的一个实例
    const url = req.url; 
    //浏览器输入localhost:9000/index.html, 那url == '/index.html'
    //console.log(url);
    const file = staticUrl + url,
        type = path.extname(url);  //path.extname 返回路径中文件的扩展名
    //console.log(type)
    type = type ? type.split('.')[1] : 'unknown'; 
    fs.readFile(file , function(err,data){
        if(err){
            console.log('访问'+staticUrl+req.url+'出错');
            res.writeHeader(404,{
                'content-type' : 'text/html;charset="utf-8"'
            });
            res.write('<h1>404错误</h1><p>你要找的页面不存在</p>');
        }else{
            res.write(data);  //将index.html显示在浏览器（客服端）
        }
        res.end();
    });
}).listen(9097,'127.0.0.1');

console.log('服务器开启成功\n\n访问路径为 http://127.0.0.1:9097/index.html\n');

node 开发调试工具

1. supervisor

监听并自动重启服务

#安装
npm install -g supervisor
#使用
supervisor 1.js

2. iron-node

简单的调试工具

#安装
npm install iron-node -g
#使用
iron-node 1.js

3. nodemon

监听并自动重启服务

#安装
npm install nodemon -g
#使用
nodemon 1.js

node 常用

执行bash命令

const exec = require('child_process').exec;
// 例如ls命令
let ls = exec('ls -al',{cwd:'/Users/mzh'},(err,stdout,stderr)=>{
    console.log(`stdout:${stdout}`);
    console.log(`stderr:${stderr}`);
    if(err !== null){
        console.log(`exec error: ${err}`);
    }
});
ls.on('exit',(code)=>{
    console.log(`child exited with code ${code}`);
});

等同于 bash

ls -al

执行特定的程序

const execFile = require('child_process').execFile;

let runFile = execFile('index.js');
runFile.stdout.on('data',data=>{
    console.log(data);
});

let runNode = execFile('node',['--version']);
let runBash = execFile('/bin/ls',['-al','/']);
runNode.stdout.on('data',data=>{
    console.log(data);
});
runBash.stdout.on('data',data=>{
    console.log(data);
});

创建一个子进程来执行特定命令

const spawn = require('child_process').spawn;
const ps = spawn('ps',['aux']);
const grep = spawn('grep',['zsh']);

ps.stdout.on('data',data=>{
    grep.stdin.write(data);
});
ps.on('close',code=>{
    if(code !== 0){
        console.log(`ps process exited with code ${code}`);
    }
    grep.stdin.end();
});
grep.stdout.on('data',data=>{
    console.log(data);
});

等同于bash

ps aux | grep zsh

开子进程运行

const fork = require('child_process').fork;
let child = fork('./child.js');
child.send('main process');
child.on('message',msg=>{
    console.log(`parent get message: ${msg}`);
});

child.js

console.log('child process running...');
process.on('message',msg=>{
    console.log(`child get message: ${msg}`);
});
setTimeout(()=>{
    process.send('child send message');
},1000);

让子进程的信息和父进程共享(父进程可以显示子进程信息)

const execSync = require('child_process').execSync;
execSync('rm -rf ./dist', {
    // stdio 设置父子进程共享的通道
    // 等同于[process.stdin, process.stdout, process.stderr];
    stdio: [0, 1, 2]
});