refactor: use process and net to improve restart and lock

Author: GrinZero

apps/koa/src/index.js

@@ -14,9 +14,8 @@ const run = () => {
   const Router = require('koa-router')
   const { createFetch } = require('ofetch')
 
-  const unregister = register({
-    autoOpenDevtool: true
-  })
+  const unregister = register()
+  register()
 
   const app = new Koa()
   const router = new Router()

packages/network-debugger/package.json

@@ -1,6 +1,6 @@
 {
   "name": "node-network-devtools",
-  "version": "1.0.18",
+  "version": "1.0.19",
   "description": "Inspecting Node.js's Network with Chrome DevTools",
   "homepage": "https://grinzero.github.io/node-network-devtools/",
   "main": "./dist/index.js",

packages/network-debugger/src/core/fork.ts

@@ -1,13 +1,20 @@
-import { IS_DEV_MODE, READY_MESSAGE, RequestDetail } from '../common'
+import { READY_MESSAGE, RequestDetail } from '../common'
 import { type IncomingMessage } from 'http'
 import WebSocket from 'ws'
 import { ChildProcess, fork } from 'child_process'
 import { __dirname } from '../common'
 import { resolve as resolvePath } from 'path'
 import { RegisterOptions } from '../common'
 import fs from 'fs'
+import { sleep, checkMainProcessAlive } from '../utils/process'
+import { unlinkSafe } from '../utils/file'
+import { warn } from '../utils'
 
-let hasLogError = false
+class ExpectError extends Error {
+  constructor(message: string) {
+    super(message)
+  }
+}
 
 export class MainProcess {
   private ws: Promise<WebSocket>
@@ -16,24 +23,34 @@ export class MainProcess {
 
   constructor(props: RegisterOptions & { key: string }) {
     this.options = props
-    this.ws = new Promise<WebSocket>((resolve, reject) => {
+    this.ws = new Promise<WebSocket>(async (resolve, reject) => {
       const lockFilePath = resolvePath(__dirname, `./${props.key}`)
       if (fs.existsSync(lockFilePath)) {
-        fs.watchFile(lockFilePath, (e) => {
-          if (!fs.existsSync(lockFilePath)) {
-            reject(new Error('MainProcess is already running'))
-          }
-        })
-        return
+        // 读取 lock 文件中的进程号
+        const pid = fs.readFileSync(lockFilePath, 'utf-8')
+        await sleep(800)
+
+        // 检测该进程是否存活且 port 是否被占用
+        const isProcessAlice = await checkMainProcessAlive(pid, props.port!)
+        if (isProcessAlice) {
+          warn(`The main process with same options is already running, skip it.`)
+          return
+        }
+        // 如果进程不存在：
+        //   1. 热更新导致 process 重启
+        //   2. 上一个进程未成功删除 lock
+        // 都应该继续往下
+        unlinkSafe(lockFilePath)
       }
-      fs.writeFileSync(lockFilePath, `LOCKED`)
+      fs.writeFileSync(lockFilePath, `${process.pid}`)
       const socket = new WebSocket(`ws://localhost:${props.port}`)
       socket.on('open', () => {
+        unlinkSafe(lockFilePath)
         resolve(socket)
       })
       socket.on('error', () => {
         this.openProcess(() => {
-          fs.unlinkSync(lockFilePath)
+          unlinkSafe(lockFilePath)
           const socket = new WebSocket(`ws://localhost:${props.port}`)
           socket.on('open', () => {
             resolve(socket)
@@ -49,14 +66,14 @@ export class MainProcess {
         })
       })
       .catch((e) => {
-        if (!hasLogError) {
-          !IS_DEV_MODE && (hasLogError = true)
-          console.warn('MainProcess Warning: ', e)
+        if (e instanceof ExpectError) {
+          return
         }
+        throw e
       })
   }
 
-  private openProcess(callback?: () => void) {
+  private openProcess(callback?: (cp: ChildProcess) => void) {
     const forkProcess = () => {
       // fork a new process with options
       const cp = fork(resolvePath(__dirname, './fork'), {
@@ -67,7 +84,7 @@ export class MainProcess {
       })
       const handleMsg = (e: any) => {
         if (e === READY_MESSAGE) {
-          callback && callback()
+          callback && callback(cp)
           cp.off('message', handleMsg)
         }
       }
@@ -81,13 +98,10 @@ export class MainProcess {
 
   public async send(data: any) {
     const ws = await this.ws.catch((err) => {
-      if (hasLogError) {
-        // has error in main process or websocket
+      if (err instanceof ExpectError) {
         return null
       }
-      !IS_DEV_MODE && (hasLogError = true)
-      console.warn('MainProcess Websocket Error: ', err)
-      return null
+      throw err
     })
     if (!ws) return
     ws.send(JSON.stringify(data))

packages/network-debugger/src/utils/console.ts

@@ -1 +1,3 @@
 export const log = console.log.bind(console, '\x1B[36m[node-network-debugger]:', '\x1B[32m')
+
+export const warn = console.warn.bind(console, '\x1B[36m[node-network-debugger](warn):', '\x1B[33m')

packages/network-debugger/src/utils/file.ts

@@ -0,0 +1,7 @@
+import fs from 'fs'
+
+export const unlinkSafe = (path: string) => {
+  try {
+    fs.unlinkSync(path)
+  } catch {}
+}

packages/network-debugger/src/utils/process.ts

@@ -0,0 +1,35 @@
+import net from 'net'
+
+export const sleep = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms))
+
+export const checkMainProcessAlive = (pid: number | string, port: number) => {
+  try {
+    if (Number(pid) === process.pid) {
+      return Promise.resolve(true)
+    }
+    process.kill(Number(pid), 0)
+
+    // 检查 port 是否被占用
+    return new Promise<boolean>((resolve) => {
+      const server = net.createServer()
+
+      server.once('error', (err: any) => {
+        if (err.code === 'EADDRINUSE') {
+          // 端口被占用
+          resolve(false)
+        }
+        // fallback 其他错误
+        resolve(false)
+      })
+
+      server.once('listening', () => {
+        // 端口未被占用
+        server.close(() => resolve(true))
+      })
+
+      server.listen(port)
+    })
+  } catch {
+    return Promise.resolve(false)
+  }
+}

packages/network-debugger/vite.config.ts

@@ -26,7 +26,8 @@ export default defineConfig(({ mode }) => ({
         'node:diagnostics_channel',
         'node:async_hooks',
         'node:buffer',
-        'stream'
+        'stream',
+        'net'
       ],
       output: {
         globals: {
@@ -43,7 +44,8 @@ export default defineConfig(({ mode }) => ({
           'node:diagnostics_channel': 'diagnostics_channel',
           'node:async_hooks': 'async_hooks',
           'node:buffer': 'buffer',
-          stream: 'stream'
+          stream: 'stream',
+          net: 'net'
         }
       }
     }