示例:发送服务器对象


例如,可以使用 sendHandle 参数将 TCP 服务器对象的句柄传给子进程,如下例所示:

const subprocess = require('node:child_process').fork('subprocess.js');

// 打开服务器对象并发送句柄。
const server = require('node:net').createServer();
server.on('connection', (socket) => {
  socket.end('handled by parent');
});
server.listen(1337, () => {
  subprocess.send('server', server);
});

然后子进程将收到服务器对象:

process.on('message', (m, server) => {
  if (m === 'server') {
    server.on('connection', (socket) => {
      socket.end('handled by child');
    });
  }
});

一旦服务器现在在父进程和子进程之间共享,则一些连接可以由父进程处理,一些连接由子进程处理。

虽然上面的示例使用使用 node:net 模块创建的服务器,但 node:dgram 模块服务器使用完全相同的工作流程,除了监听 'message' 事件而不是 'connection' 和使用 server.bind() 而不是 server.listen()。 但是,这仅在 Unix 平台上受支持。

The sendHandle argument can be used, for instance, to pass the handle of a TCP server object to the child process as illustrated in the example below:

const subprocess = require('node:child_process').fork('subprocess.js');

// Open up the server object and send the handle.
const server = require('node:net').createServer();
server.on('connection', (socket) => {
  socket.end('handled by parent');
});
server.listen(1337, () => {
  subprocess.send('server', server);
});

The child would then receive the server object as:

process.on('message', (m, server) => {
  if (m === 'server') {
    server.on('connection', (socket) => {
      socket.end('handled by child');
    });
  }
});

Once the server is now shared between the parent and child, some connections can be handled by the parent and some by the child.

While the example above uses a server created using the node:net module, node:dgram module servers use exactly the same workflow with the exceptions of listening on a 'message' event instead of 'connection' and using server.bind() instead of server.listen(). This is, however, only supported on Unix platforms.