Node.js C++ 插件：线程

Node.js 是一个基于 Chrome V8 引擎的 JavaScript 运行环境，它允许开发者使用 JavaScript 构建高性能的网络应用程序。Node.js 作为一个事件驱动、非阻塞 I/O 的平台，具备了处理高并发请求的能力。虽然 Node.js 在单线程的情况下就能胜任大多数任务，但有些场景下需要借助 C++ 插件来实现多线程的功能。

javascript
const { Worker } = require('worker_threads');
function runWorker() {
  return new Promise((resolve, reject) => {
    const worker = new Worker('./worker.js');
    worker.on('message', (message) => {
      console.log('Received message from worker:', message);
      resolve();
    });
    worker.on('error', (error) => {
      console.error('Error occurred in worker:', error);
      reject(error);
    });
    worker.on('exit', (code) => {
      console.log('Worker exited with code:', code);
    });
  });
}
runWorker().catch((error) => {
  console.error('An error occurred:', error);
});

javascript
// worker.js
const { parentPort } = require('worker_threads');
parentPort.postMessage('Hello from worker');
parentPort.on('message', (message) => {
  console.log('Received message from main thread:', message);
});
// main.js
const { Worker } = require('worker_threads');
function runWorker() {
  return new Promise((resolve, reject) => {
    const worker = new Worker('./worker.js');
    worker.on('message', (message) => {
      console.log('Received message from worker:', message);
      resolve();
    });
    worker.on('error', (error) => {
      console.error('Error occurred in worker:', error);
      reject(error);
    });
    worker.on('exit', (code) => {
      console.log('Worker exited with code:', code);
    });
    worker.postMessage('Hello from main thread');
  });
}
runWorker().catch((error) => {
  console.error('An error occurred:', error);
});

javascript
// worker.js
const { parentPort } = require('worker_threads');
parentPort.on('message', (message) => {
  const result = computeResult(message);
  parentPort.postMessage(result);
});
function computeResult(data) {
  // Perform complex calculations here
  return data * 2;
}
// main.js
const { Worker } = require('worker_threads');
function runWorkers() {
  const data = [1, 2, 3, 4, 5];
  const workers = [];
  for (let i = 0; i < data.length; i++) {
    const worker = new Worker('./worker.js');
    workers.push(worker);
    worker.on('message', (message) => {
      console.log('Received result:', message);
    });
    worker.postMessage(data[i]);
  }
  return new Promise((resolve, reject) => {
    let completed = 0;
    workers.forEach((worker) => {
      worker.on('message', () => {
        completed++;
        if (completed === data.length) {
          resolve();
        }
      });
      worker.on('error', (error) => {
        reject(error);
      });
    });
  });
}
runWorkers().catch((error) => {
  console.error('An error occurred:', error);
});