Nodejs搭建多进程Web服务器实现过程

// main.js
const { fork } = require('child_process');
const normal = fork('subprocess.js', ['normal']);
const special = fork('subprocess.js', ['special']);
// Open up the server and send sockets to child. Use pauseOnConnect to prevent
// 套接字在发送给子进程之前不会被读取
const server = require('net').createServer({ pauseOnConnect: true });
let flag = 0;
server.on('connection', (socket) => {
  flag++;
  // this is special priority.
  if (flag % 2 === 0) {
    special.send('socket', socket);
    return;
  }
  // This is normal priority.
  normal.send('socket', socket);
});
server.listen(1337);

// subprocess.js
process.on('message', (m, socket) => {
  if (m === 'socket') {
    // Check that the client socket exists. 
    // It is possible for the socket to be closed between the time it is
    if (socket) {
      // console.log(`Request handled with ${process.argv[2]} priority`);
      socket.end(`Request handled with ${process.argv[2]} priority, running on ${process.pid}`);
    }
  }
});

const cp = require("child_process");
for (let i = 0; i < 10; i++) {
  cp.exec(`curl --http0.9 "http://127.0.0.1:1337"`, (err, stdout, stderr) => {
    console.log(`finished: ${i}, and received: `, stdout);
  })
}

child.send(message, [sendHandle]);

// 子进程
child.kill([signal]);
// 当前进程
process.kill(pid, [signal]);
// 监听
process.on(signal, callback)

process.on('SIGTERM', () => {
    console.log("got sigterm, exiting...");
    process.exit(1);
});
console.log("process running on: ", process.pid);
process.kill(process.pid, "SIGTERM");

// master.js
// master.js
const { fork } = require('child_process');
const cpus = require('os').cpus();
const server = require('net').createServer();
server.listen(1337);
const workers = {};
// process.on('uncaughtException', function (err) {
//   console.log(`Master uncaughtException:\r\n`);
//   console.log(err);
// });
const createWorker = () => {
  const worker = fork('./worker.js');
  // 收到信号后立即重启新进程
  worker.on('message', function (message) {
    if (message.act === 'suicide') {
      createWorker();
    }
  });
  // 某个进程终止时重新启动新的进程
  worker.on('exit', () => {
    console.log('Worker ' + worker.pid + ' exited.');
    delete workers[worker.pid];
    // createWorker();
  });
  // 句柄转发
  worker.send('server', server);
  workers[worker.pid] = worker;
  console.log('Create worker. pid: ' + worker.pid);
};
for (let i = 0; i < cpus.length; i++) {
  createWorker();
}
// server.close();
// 进程自己退出时，让所有工作进程退出
process.on('exit', () => {
  for (let pid in workers) {
    workers[pid].kill();
  }
});

// worker.js
const http = require('http');
const server = http.createServer((req, res) => {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('handled by child, pid is ' + process.pid + '\n');
  // 抛出异常，捕获后终止进程
  throw new Error('throw exception');
});
var worker;
process.on('message', (m, tcp) => {
  if (m === 'server') {
    worker = tcp;
    worker.on('connection', (socket) => {
      server.emit('connection', socket);
    });
  }
});
// 捕获异常后终止进程
process.on('uncaughtException', (err) => {
  // 主动发出信号，避免等待连接断开时收到新请求而缺少进程无法响应
  process.send({
    act: 'suicide'
  });
  // 停止接收新的连接
  worker.close(function () {
    // 所有已有连接断开后，退出进程
    process.exit(1);
  });
  // 避免长连接请求长时间无法终止，5s后自动终止
  setTimeout(() => {
    process.exit(1);
  }, 5000)
});

const cp = require("child_process");
const cpus = require("os").cpus();
const sleep = (delay) => {
  const now = Date.now();
  while (Date.now() - now < delay);
  return;
}
for (let i = 0; i < cpus.length; i++) {
  const out = cp.execSync(`curl --http0.9 "http://127.0.0.1:1337"`);
  sleep(1000);
  console.log(out.toString());
}