cluster method in node js code example
Example 1: node cluster
const cluster = require('cluster');
const http = require('http');
const numCPUs = require('os').cpus().length;
if (cluster.isMaster) {
console.log(`Master ${process.pid} is running`);
for (let i = 0; i < numCPUs; i++) {
cluster.fork();
}
cluster.on('exit', (worker, code, signal) => {
console.log(`worker ${worker.process.pid} died`);
});
} else {
http.createServer((req, res) => {
res.writeHead(200);
res.end('hello world\n');
}).listen(8000);
console.log(`Worker ${process.pid} started`);
}
Example 2: nodejs cluster example
import http, { Server } from 'http'
import cluster, { Worker } from 'cluster'
import { cpus, CpuInfo } from 'os'
import consola from 'consola'
import chalk from 'chalk'
import app from './src/app'
const coreThread: CpuInfo[] = cpus()
if (cluster.isMaster) {
for (let i = 0; i < coreThread.length; i++) {
cluster.fork()
}
const workersTread: any = []
for (const id in cluster.workers) {
workersTread.push(id)
}
workersTread.forEach(
async (pid: number, _: number): Promise<void> => {
await cluster.workers[pid].send({
from: 'isMaster',
type: 'SIGKILL',
message: 'cleanup is worker dead and change to new worker'
})
}
)
if (process.env.NODE_ENV !== 'production') {
cluster.on('online', (worker: Worker): void => {
if (worker.isConnected()) {
console.info(`${chalk.greenBright('worker active pid')}: ${worker.process.pid}`)
}
})
cluster.on('exit', (worker: Worker, code: number, signal: string): void => {
if (worker.isDead()) {
console.info(`${chalk.redBright('worker dead pid')}: ${worker.process.pid}`)
}
cluster.fork()
})
}
} else {
const server = http.createServer(app) as Server
const host: any = process.env.HOST
const port: any = process.env.PORT
server.listen(port, host, (): void => consola.success(`server is running on ${port}`))
}