请问在node.js退出之前执行清理操作

Question

在node.js退出之前执行清理操作

我想告诉node.js总是在它退出之前做一些事情，不管出于什么原因-Ctrl+C、异常或任何其他原因。

我试过这个：

process.on('exit', function (){
  console.log('Goodbye!');});

开始这个过程，杀死它，什么也没有发生；再次启动，按下Ctrl+C，仍然什么也没发生.

Answer 1

最新情况：您可以为process.on('exit')而在任何其他情况下(SIGINT或未处理的异常)调用process.exit()process.stdin.resume();//so the program will not close instantlyfunction exitHandler(options, exitCode) {     if (options.cleanup) console.log('clean');     if (exitCode || exitCode === 0) console.log(exitCode);     if (options.exit) process.exit();}//do something when app is closingprocess.on('exit', exitHandler.bind(null,{cleanup:true}));     //catches ctrl+c eventprocess.on('SIGINT', exitHandler.bind(null, {exit:true}));     // catches "kill pid" (for example: nodemon restart)process.on('SIGUSR1', exitHandler.bind(null, {exit:true}));     process.on('SIGUSR2', exitHandler.bind(null, {exit:true}));     //catches uncaught exceptionsprocess.on('uncaughtException', exitHandler.bind(null, {exit:true}));

Answer 2

下面的脚本允许对所有退出条件都有一个处理程序。它使用一个特定于应用程序的回调函数来执行自定义清理代码。Clearup.js// Object to capture process exits and call app specific cleanup functionfunction noOp() {};exports.Cleanup = function Cleanup(callback) {  // attach user callback to the process event emitter  // if no callback, it will still exit gracefully on Ctrl-C  callback = callback || noOp;  process.on('cleanup',callback);  // do app specific cleaning before exiting  process.on('exit', function () {    process.emit('cleanup');  });  // catch ctrl+c event and exit normally  process.on('SIGINT', function () {    console.log('Ctrl-C...');    process.exit(2);  });  //catch uncaught exceptions, trace, then exit normally  process.on('uncaughtException', function(e) {    console.log('Uncaught Exception...');    console.log(e.stack);    process.exit(99);  });};这段代码截取了未识别的异常、Ctrl-C和正常的退出事件。然后，它在退出之前调用一个可选的用户清理回调函数，用一个对象处理所有退出条件。该模块只是扩展Process对象，而不是定义另一个事件发射器。如果没有应用程序特定的回调，清理默认为无OP函数。当Ctrl-C退出时，子进程仍在运行，这对我的使用来说已经足够了。您可以根据需要轻松添加其他退出事件，如SIGHUP。注意：根据NodeJS手册，SIGKILL不能有侦听器。下面的测试代码演示了使用Clearup.js的各种方法// test cleanup.js on version 0.10.21// loads module and registers app specific cleanup callback...var cleanup = require('./cleanup').Cleanup(myCleanup);//var cleanup = require('./cleanup').Cleanup(); // will call noOp// defines app specific callback...function myCleanup() {  console.log('App specific cleanup code...');};// All of the following code is only needed for test demo// Prevents the program from closing instantlyprocess.stdin.resume();// Emits an uncaught exception when called because module does not existfunction error() {  console.log('error');  var x = require('');};// Try each of the following one at a time:// Uncomment the next line to test exiting on an uncaught exception//setTimeout(error,2000);// Uncomment the next line to test exiting normally//setTimeout(function(){process.exit(3)}, 2000);// Type Ctrl-C to test forced exit