如何正确停止Node API群集服务器？

如何解决如何正确停止Node API群集服务器？

我只是在学习在Koa + TypeScript API中使用集群。我找到了一篇博客文章，并从中引用了文章。

// server.ts

import {app} from './app' // Koa

export function server() {
  const http = app.listen(8000,async () => {
    console.info(`Listening at 8000`)
  })
  return http
}

// main.ts

async function main() {
  try {
    // Create or migrate
    await knex.migrate.latest()
    return server()
  } catch (err) {
    logger.error('Failed to start: ',err.stack)
    process.exit(1)
  }
}

// Clustering
const numCPUs = cpus().length

if (cluster.isMaster) {
  logger.info(`${numCPUs} CPUs available`)
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork()
  }

  cluster.on('online',worker => {
    logger.info(`Worker ${worker.process.pid} is online`)
  })

  cluster.on('disconnect',worker => {
    logger.error(`${worker.process.pid} disconnect!`)
    cluster.fork()
  })

  /** I do not think I need this block,right?
   *
  cluster.on('exit',(worker,code,signal) => {
    logger.info(
      `Worker ${worker.process.pid} died with code: ${code} and signal: ${signal}`,)
    logger.info('Starting a new worker...')
    cluster.fork()
  })
   */
} else {
  main()
}

我有这个正常的关机功能：

// Graceful shutdown
async function shutdown() {
  try {
    await knex.destroy().then(() => {
      logger.warn('Destroyed Knex pool')
    })
    // Make sure we close down within 30 seconds
    const killtimer = setTimeout(() => {
      process.exit(1)
    },30000)
    // But don't keep the process open just for that!
    killtimer.unref()
    server().close(() => {
      logger.warn('Closed server')
      process.exit()
    })
    // Let the maste know w're dead.
    // return cluster.worker.disconnect()
  } catch (e) {
    logger.error(`Error during disconnection: ${e.stack}`)
    process.exit(1)
  }
}

function awaitHardStop() {
  const timeout = SHUTDOWN_TIMEOUT ? +SHUTDOWN_TIMEOUT : 1000 * 30
  return setTimeout(() => {
    logger.error(`Process did not terminate within ${timeout}ms. Stopping now!`)
    process.nextTick(process.exit(1))
  },timeout)
}

// Catch unhandling unexpected exceptions
process.on('uncaughtException',e => {
  logger.error(`Uncaught exception: ${e.message}`)
  process.nextTick(process.exit(1))
})

// Catch unhandling rejected promises
process.on('unhandledRejection',(reason,promise) => {
  logger.error(`Unhandled rejection at ${promise},reason: ${reason}`)
  process.nextTick(process.exit(1))
})

process.on('SIGINT',async () => {
  logger.warn(`[ SIGNAL ] - SIGINT`)
  const timer = awaitHardStop()
  await shutdown()
  clearTimeout(timer)
})

process.on('SIGTERM',async () => {
  logger.warn(`[ SIGNAL ] - SIGTERM`)
  const timer = awaitHardStop()
  await shutdown()
  clearTimeout(timer)
})

process.on('SIGUSR2',async () => {
  logger.warn(`[ SIGNAL ] - SIGUSR2`)
  const timer = awaitHardStop()
  await shutdown()
  clearTimeout(timer)
})

当我停在Ctrl+c上时，我明白了吗？

Error: listen EADDRINUSE: address already in use :::8000
    at Server.setupListenHandle [as _listen2] (net.js:1313:16)
    at listenInCluster (net.js:1361:12)
    at Server.listen (net.js:1447:7)
    at Application.listen (/home/usr/workspace/koa-ts/app/node_modules/koa/lib/application.js:82:19)
    at Object.server (/home/usr/workspace/koa-ts/app/src/core/server.ts:7:20)
    at /home/usr/workspace/koa-ts/app/src/main.ts:71:5
    at Generator.next (<anonymous>)
    at fulfilled (/home/usr/workspace/koa-ts/app/src/main.ts:24:58)
{"level":50,"time":1597173528053,"pid":284878,"hostname":"usr-PC","msg":"Uncaught exception: listen EADDRINUSE: address already in use :::8000"}

所以我尝试在main.ts下方的server().close()中添加此行：

    ...
    // Let the maste know w're dead.
    return cluster.worker.disconnect()
    ...

然后我在Ctrl+c时得到了这个信息：

Error: listen EADDRINUSE: address already in use :::8000
    at Server.setupListenHandle [as _listen2] (net.js:1313:16)
    at listenInCluster (net.js:1361:12)
    at Server.listen (net.js:1447:7)
    at Application.listen (/home/usr/workspace/koa-ts/app/node_modules/koa/lib/application.js:82:19)
    at Object.server (/home/usr/workspace/koa-ts/app/src/core/server.ts:7:20)
    at /home/usr/workspace/koa-ts/app/src/main.ts:71:5
    at Generator.next (<anonymous>)
    at fulfilled (/home/usr/workspace/koa-ts/app/src/main.ts:24:58)
{"level":50,"msg":"Uncaught exception: listen EADDRINUSE: address already in use :::8000"}
{"level":50,"time":1597173554364,"pid":285843,"msg":"Error during disconnection: TypeError: Cannot read property 'disconnect' of undefined\n    at /home/usr/workspace/koa-ts/app/src/main.ts:76:27\n    at Generator.next (<anonymous>)\n    at fulfilled (/home/usr/workspace/koa-ts/app/src/main.ts:24:58)"}
{"level":50,"msg":"Error during disconnection: TypeError: Cannot read property 'disconnect' of undefined\n    at /home/usr/workspace/koa-ts/app/src/main.ts:76:27\n    at Generator.next (<anonymous>)\n    at fulfilled (/home/usr/workspace/koa-ts/app/src/main.ts:24:58)"}
llsi/app/src/main.ts:24:58)"}
{"level":50,"time":1597173997176,"pid":287724,"msg":"Error during disconnection: TypeError: Cannot read property 'disconnect' of undefined\n    at /home/usr/workspace/koa-ts/app/src/main.ts:76:27\n    at Generator.next (<anonymous>)\n    at fulfilled (/home/usr/workspace/koa-ts/app/src/main.ts:24:58)"}

这正常吗？还是我在做错什么？

我正在使用Node（v12.18.3）。

参考：http://bisaga.com/blog/programming/create-a-node-cluster-with-koa-and-typescript/

解决方法

Doing a cleanup action just before Node.js exits

查看此处的建议。我也在寻找一种对任何形式的进程终止进行清理的方法...您基本上应该只在清理为真时才终止。另外，我建议您调查流程经理。例如检出PM2，它使您可以轻松地在集群中启动应用程序并为您管理不同的工作进程！