24
votes

EDIT After further testing, I have found that this is happening with both gulp and grunt on this app and on the default install of mean.js. I'm running this locally on a Mac. When I running either app using "node server.js" they don't crash.

I'm using a MEAN stack with grunt-nodemon and node is crashing when an express URL is accessed. It isn't always consistent though. Sometimes it works, sometimes node crashes right when the URL is hit retiring no data, and other times I get a response and node crashed immediately after.

Browser console response:

http://localhost:8000/api/users net::ERR_CONNECTION_REFUSED

Terminal output:

Mongoose: users.insert({ firstname: 'mike', lastname: 'jones', email:'[email protected]', role: 'admin', password: 'mike', _id: ObjectId("57485c16fc11894b96c28057"), created: new Date("Fri, 27 May 2016 14:39:18 GMT"), __v: 0 })   
user.save success
node crash
[nodemon] app crashed - waiting for file changes before starting...

In this case, the POST request went through, the user was added, then node crashed, but sometimes it crashes before a successful POST. Node also occasionally crashes on the GET request.

gruntfile.js:

module.exports = function(grunt) {
    // Load grunt tasks automatically
    require('load-grunt-tasks')(grunt);

    var pkg = grunt.file.readJSON('package.json');

    var options = {
        paths: {
            app: 'app',
            assets: 'app/assets',
            dist: 'app/dist',
            distAssets: 'app/dist/assets',
            html: 'app/html',
            htmlTmp: '.tmp/htmlsnapshot',
            htmlAssets: 'app/html/assets',
            index: 'app/dist/index.html',
            indexDev: 'app/index.html',
            indexTmp: '.tmp/html/index.html'
        },
        pkg: pkg,
        env: {
            test: {
                NODE_ENV: 'test'
            },
            dev: {
                NODE_ENV: 'development'
            },
            prod: {
                NODE_ENV: 'production'
            }
        }
    };

    // Load grunt configurations automatically
    var configs = require('load-grunt-configs')(grunt, options);

    // Define the configuration for all the tasks
    grunt.initConfig(configs);

    // Connect to the MongoDB instance and load the models
    grunt.task.registerTask('mongoose', 'Task that connects to the MongoDB instance and loads the application models.', function () {
        // Get the callback
        var done = this.async();

        // Use mongoose configuration
        var mongoose = require('./config/lib/mongoose.js');

        // Connect to database
        mongoose.connect(function (db) {
            done();
        });
    });

    grunt.registerTask('bumper', ['bump-only']);
    grunt.registerTask('css', ['sass']);
    grunt.registerTask('default', [
        'sass',
        'copy:dev',
        'nodemon',
        'concurrent:dev',
        'watch',
        'mongoose'
    ]);

    grunt.registerTask('shared', [
        'clean:demo',
        'copy:demo',
        'sass',
        'ngconstant',
        'useminPrepare',
        'concat:generated',
        'cssmin:generated',
        'uglify:generated',
        'filerev',
        'usemin',
        'imagemin',
        'usebanner'
    ]);

    grunt.registerTask('demo', [
        'shared',
        'copy:postusemin',
        'grep:demo'
    ]);

    grunt.registerTask('dist', [
        'shared',
        'copy:postusemin',
        'copy:dist',
        'grep:dist',
        'compress',
        'copy:postusemin',
        'grep:demo',
    ]);

    grunt.loadNpmTasks('grunt-forever');

};

default.js

module.exports.tasks = {
    // version update
    bump: {
        options: {
            files: ['package.json', 'bower.json'],
            pushTo: 'origin'
        }
    },

    // application constants
    ngconstant: {
        options: {
            dest: '<%= paths.assets %>/js/app.constants.js',
            name: 'app.constants',
        }
    },

    // remove all bs from css
    cssmin: {
        options: {
            keepSpecialComments: 0
        }
    },
    markdown: {
        all: {
            files: [
                {
                    src: 'README.md',
                    dest: '<%= paths.assets %>/tpl/documentation.html'
                }
            ],
            options: {
                template: '<%= paths.assets %>/tpl/_documentation_template.html',
            }
        }
    }
};

dev.js:

var _ = require('lodash'),
defaultAssets = require('./assets/default'),
testAssets = require('./assets/test'),
testConfig = require('./env/test'),
fs = require('fs'),
path = require('path');

module.exports.tasks = {
    // copy files to correct folders
    copy: {
        dev: {
            files: [
                { expand: true, src: '**', cwd: '<%= paths.app %>/bower_components/font-awesome/fonts',                    dest: '<%= paths.assets %>/fonts' },
                { expand: true, src: '**', cwd: '<%= paths.app %>/bower_components/material-design-iconic-font/fonts',     dest: '<%= paths.assets %>/fonts' },
                { expand: true, src: '**', cwd: '<%= paths.app %>/bower_components/roboto-fontface/fonts',                 dest: '<%= paths.assets %>/fonts' },
                { expand: true, src: '**', cwd: '<%= paths.app %>/bower_components/weather-icons/font',                    dest: '<%= paths.assets %>/fonts' },
                { expand: true, src: '**', cwd: '<%= paths.app %>/bower_components/bootstrap-sass/assets/fonts/bootstrap', dest: '<%= paths.assets %>/fonts' }
            ]
        }
    },

    // watch for changes during development
    watch: {
        js: {
            files: ['Gruntfile.js', '<%= paths.assets %>/js/**/*.js'],
            tasks: ['jshint'],
            options: {
                livereload: true
            }
        },
        css: {
            files: [
                '<%= paths.assets %>/css/**/*.scss'
            ],
            tasks: ['sass'],
            options: {
                livereload: true
            }
        },
        markdown: {
            files: [
                'README.md'
            ],
            tasks: ['markdown']
        },
        tasks:  [ 'express:dev' ],
    },

    // debug while developing
    jshint: {
        all: ['Gruntfile.js', '<%= paths.assets %>/js/**/*.js']
    },
    concurrent: {
        dev: {
            tasks: ['nodemon', 'node-inspector', 'watch'],
            options: {
                logConcurrentOutput: true
            }
        }
    },
    nodemon: {
        dev: {
            script: 'server.js',
            options: {
                nodeArgs: ['--debug'],
                ext: 'js,html',
                callback: function (nodemon) {

                    nodemon.on('crash', function (event) {
                        console.log(event);
                    });


                },
                watch: _.union(defaultAssets.server.gruntConfig, defaultAssets.server.views, defaultAssets.server.allJS, defaultAssets.server.config)
            }
        }
    },
    forever: {
        server1: {
            options: {
                index: 'server.js',
                //logDir: 'logs'
            }
        }
    }
};

Angular controller function:

  $scope.addUser = function(){

      var user = {
          firstname: $scope.firstname,
          lastname: $scope.lastname,
          email: $scope.email,
          role: $scope.role.selected,
          password: $scope.password
      };

      $http.post('/api/userAdd', user ).then(function successCallback(response) {
          $location.path('/users');
      }, function errorCallback(response) {
          console.log('error addding user');
          console.log(response);
      });
  };

Express route:

User = require('../models/user.js');

module.exports = function (app) {

    app.get('/api/users', function (req, res) {

        User.find({}, function (err, users) {
            if ( err ) {
                res.send({
                    message : 'error finding users',
                    success: false
                });
            } else {
                res.json(users);
            }
        });

    });

    app.get('/api/users', function (req, res) {
        User.find({fields: {}}, function (err, docs) {
            res.json(docs);
        });
    });

    app.post('/api/userAdd', function (req, res) {

        var user = new User(req.body);

        user.save( function( err, user ){

            if (err){
                console.log('user.save error');
                console.log(err);
                res.send({
                    success: false
                });
            } else {
                console.log('user.save success');
                res.send({
                    success: true
                });
            }
        });

    });

};

I'm also testing with Chromes Advanced REST extension and with any request using this tool node crashes immediately.

I'm new to MEAN so am I missing something here that is causing the crash? Any ideas?

15
Try running your server manually and see if any errors get printed before it crashes: node server.js - robertklep
Running manually seems to solve the problem, thank. Does that mean I have some issue or misconfiguration with Grunt? - MTD
Not really. I assumed that by running it standalone, you would get to see why it crashes. It wasn't supposed to work better that way ;D - robertklep
Added the full gruntfile.js, default.js, and dev.js that are being used and cause the error. Hoping that helps somehow. - MTD
Now testing with node --debug server.js I get the error message Segmentation fault: 11 and node crashes. But if I don't use --debug there is no crash and no error message - MTD

15 Answers

36
votes

This is happening because of all the running server process in the background. So all you need to do is stop them from the terminal.

Quick trick


FOR LINUX

Kill them all by running this on terminal :

pkill -f node

and then restart nodemon.


FOR Window

 1. Go to the task manager
 2. Then search-for node.js server-side javascript
 3. Then right click on it and end-task from the processes. 

Then restart the server. It will work fine.

14
votes

for windows users, go to the task manager and then find for node.js server-side javascript, and end task on the process. then try again with your command.

4
votes

Issue : app crashed - waiting for file changes before starting...

There could be different reasons:

1. Running node in background

pkill -f node

Worked in Mac OS ,did not work in Microsoft.

2.Server.js and package.json are not in same folder . Check it .

check package.json

"scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
     "start": "nodemon Server.js"
 }
4
votes

In the terminal using the below command to kill the existing running port and restart your service.

killall -9 node

or to kill a particular port instead of all

sudo lsof -i :3000 //replace 3000 with your port number
sudo kill -9 31363 // replace 31363 with your PID
2
votes

I update node from v4.2.6 to v4.4.5 fixed the issue with the default mean.js install. I'll build out from there.

2
votes

Sometimes it happenes when you forget to source your .env files

1
votes

Most likely your node daemon is still running.

ps -eaf | grep node

if it gives something like

abhinav 15759 15748 0 19:30 pts/2 00:00:00 sh -c nodemon server.js abhinav 15760 15759 0 19:30 pts/2 00:00:00 node /home/abhinav/Documents/Projects/WebD/Node/smartbrain/smart-brain-api/node_modules/.bin/nodemon server.js abhinav 15812 15801 0 19:31 pts/2 00:00:00 sh -c nodemon server.js

then try:

killall node

0
votes

I encountered this challenge when working on nexmo sms app.

To fix the crashing, go to your app.js. If you have these lines of code. Its normally on the very first lines...

`import { Socket } from 'dgram';`

`const express = require('express');`
`const bodyParser = require('body-parser');`
`const ejs = require('ejs');`
`const Nexmo = require('nexmo');`
`const socketio = require('socket.io');`

Simply delete/remove the first line of code import { Socket } from 'dgram';

Leaving these ones...

    `const express = require('express');`
    `const bodyParser = require('body-parser');`
    `const ejs = require('ejs');`
    `const Nexmo = require('nexmo');`
    `const socketio = require('socket.io');`

and restart your application using "nodemon"

Did it work?

0
votes

This can happen with incorrect paths.

Example: If your nodemon server.js path is in D:\Ex-Track\mern-exercise but If you are didn't use the full path D:\Ex-Track in your grunt, this can cause nodemon to fail.

0
votes

In case your PORT is used by previous node process(tasks)

Run command netstat -a -n -o | find "8080" cmd1

And pass opened task using below command

taskkill /F /PID "1544"

cmd2

0
votes

This usually happens when you make changes to the server, while your server is running. For instead when you git pull to make changes to your server. Therefore, you need to kill the PID of the server that is running.

On windows you need to run the following commands:

> **netstat -ano|findstr "PID :3000"** // Replace 3000 with the port number
> **taskkill /pid 18264 /f** // Replace the 18264 with the pid number you received by running the first command

On Linux/Unix system you need to run the following commands:

> **lsof -i tcp:3000**
> **Kill -9 18264** 
0
votes

!!! that works for me 👍

[nodemon] app crashed - waiting for file changes before starting... means you changes the file exactly at the time you save (nodemon debugger) working, try to use history to go back your changes. just that. if your changes can not be back from history do these steps:

Delete your nodemon in your ROOT node module like in this picture

MacBook-Pro:/usr/local/lib$ cd node_modules/
MacBook-Pro:/usr/local/lib/node_modules$ ls
expo-cli/         npm/              react-native-cli/
nodemon/          react-devtools/
MacBook-Pro:/usr/local/lib/node_modules$ sudo rm -R n
nodemon/ npm/     
MacBook-Pro:/usr/local/lib/node_modules$ sudo rm -R nodemon/
MacBook-Pro:/usr/local/lib/node_modules$ 

then install nodmon again !!

0
votes

Try changing the default user password in mongoDB (Database Access->user). This solved the issue for me.

0
votes

I think this error can be caused for many reasons (it is not a very descriptive error to be honest), in my case it was because the "html-pdf" module had conflicts, I removed it and now the error is gone!.

-1
votes

Make sure your system time is not backward and higher. Reset your system time, so it could connect to the mongoose server if you are using online db.