Core: Nodemon keeps crashing and makes development a pain

Created on 2 Jul 2017 · 17Comments · Source: adonisjs/core

Hello,

I followed the instructions in the docs, and I have websokcet and app (version 3.2) running on port 3333. After npm run serve:dev everything works well. However, if my code has an error, then the app crashes and it never restarts. It gets stuck with the message I am including below here, and the only way so far I found out of it is to exit, lsof -i tcp:3333, kill the node processes, and again run npm run serve:dev. I am repeating this loop every other minute as of now. It's very annoying and makes development a pain, please help!

Node version: v6.9.2
Npm version: 3.10.8
Error message:

info adonis:framework +0ms serving app on localhost:3333
events.js:160
throw er; // Unhandled 'error' event
^

Error: listen EADDRINUSE 127.0.0.1:3333
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at Server._listen2 (net.js:1259:14)
at listen (net.js:1295:10)
at net.js:1405:9
at GetAddrInfoReqWrap.asyncCallback [as callback] (dns.js:62:16)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:81:10)
[nodemon] app crashed - waiting for file changes before starting...

Source

rezatrojan

Most helpful comment

Hey @alaghband ! 👋

As the error say, the address 127.0.0. 1 with the port 3333 is already used by some process, try to change the port into your .env file or find which process use them!

RomainLanz on 2 Jul 2017

👍2

All 17 comments

Hey @alaghband ! 👋

As the error say, the address 127.0.0. 1 with the port 3333 is already used by some process, try to change the port into your .env file or find which process use them!

RomainLanz on 2 Jul 2017

👍2

Thanks. I tried that, but still same issue keeps appearing. The process that occupies the port is node itself, initiated by adonisjs. The problem seems to be that on restart the port is not freed up and hence the error

rezatrojan on 2 Jul 2017

May you try to update npm?

$ npm i -g npm

Then try again and display the output of npm run serve:dev.

RomainLanz on 2 Jul 2017

Sure! Here it is: Following the previous suggestion, I changed port to 3000. Then I successfully ran npm i -g npm. Then:

npm run serve:dev

[email protected] serve:dev /Users/R/Documents/Projects/Node/Adonis-Apps/test-app
nodemon --watch app --watch bootstrap --watch config --watch .env -x node server.js

[nodemon] 1.11.0
[nodemon] to restart at any time, enter rs
[nodemon] watching: /Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app//* /Users/R/Documents/Projects/Node/Adonis-Apps/test-app/bootstrap//* /Users/R/Documents/Projects/Node/Adonis-Apps/test-app/config/*/ .env
[nodemon] starting node server.js
info adonis:framework +0ms serving app on localhost:3000
[nodemon] restarting due to changes...
[nodemon] starting node server.js

/Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Model/User.js:29
const seated = room.seats().where(');
^
ParseError: Unterminated string constant
at /Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Ws/socket.js (/Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Ws/socket.js:1:1)
[nodemon] clean exit - waiting for changes before restart
[nodemon] restarting due to changes...
[nodemon] starting node server.js
info adonis:framework +0ms serving app on localhost:3000
[nodemon] restarting due to changes...
[nodemon] starting node server.js
info adonis:framework +0ms serving app on localhost:3000
events.js:160
throw er; // Unhandled 'error' event
^

rezatrojan on 3 Jul 2017

You have an error in your code.

/Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Model/User.js:29
const seated = room.seats().where(');

but it seems that there's another problem.
Any idea @thetutlage?

RomainLanz on 3 Jul 2017

Yes there is an exception thrown due to syntax error and since you are running adonis via nodemon, it keeps the port busy and expect you to fix the error

thetutlage on 4 Jul 2017

@RomainLanz I understand I have an error, it was intentional so I could produce an error log and share with you. But isn't having errors part of development process anyway?

@thetutlage "it keeps the port busy and expect you to fix the error" Even after fixing the syntax error it won't get back to life, it's simply stuck there forever until I exit and restart.

I have been using Laravel for years, and that's why I got initially interested in Adonisjs. I have never seen Laravel get stuck because of such errors in my code. It's always ready for my changes! As of now, with adonisjs, what I have to do is to find the processes running on the port, kill them, and restart. And worst part is I have to do it every 2 minutes - I am spending more time on finding, killing, and restarting than the actual development!!! I am sure it does not have to be that way and you guys do it differently. Please do share what I have to do differently to not get stuck with occupied ports while doing development and naturally having errors along the way. Thanks a ton!
///////////////////////
This is what happens after fixing errors (essentially now that error is fixed it's complaining about port being occupied and I have found no way out of this other than exit and restart)

[nodemon] restarting due to changes...
[nodemon] starting node server.js
info adonis:framework +0ms serving app on localhost:3000
events.js:160
throw er; // Unhandled 'error' event
^

Error: listen EADDRINUSE 127.0.0.1:3000
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at Server._listen2 (net.js:1259:14)
at listen (net.js:1295:10)
at net.js:1405:9
at GetAddrInfoReqWrap.asyncCallback [as callback] (dns.js:62:16)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:81:10)
[nodemon] app crashed - waiting for file changes before starting...
[nodemon] restarting due to changes...
[nodemon] starting node server.js
info adonis:framework +0ms serving app on localhost:3000
events.js:160
throw er; // Unhandled 'error' event
^

rezatrojan on 4 Jul 2017

👍1

Nodejs doesn't work the way Php works, I suggest understanding the merits of Nodejs over php first and then try to use Adonisjs or any other framework

Comparing apples to oranges will not help much

thetutlage on 4 Jul 2017

The very last line says [nodemon] app crashed - waiting for file changes before starting...

Which means it's waiting for u to fix the error and port is still in use

thetutlage on 4 Jul 2017

Thanks. Error was fixed but it doesn't seem to open up the port even after the fix.

rezatrojan on 4 Jul 2017

@alaghband Okay let's do it together from scratch, without using nodemon.

Free up all the port
Use npm run serve to run the app, this doesn't makes use of nodemon and will start the server normally.
Now make some syntax error and lemme know if after the crash you are able to restart the process on same port.

thetutlage on 5 Jul 2017

// ENGINEERING A SYNTAX ERROR BY CHANGING "IF" TO "F" AND:

npm run serve

[email protected] serve /Users/R/Documents/Projects/Node/Adonis-Apps/test-app
node server.js

/Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Model/User.js:40
f (seat.user_id === null) {
^
ParseError: Unexpected token
at /Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Ws/socket.js (/Users/R/Documents/Projects/Node/Adonis-Apps/test-app/app/Ws/socket.js:1:1)

// APP CRASHED. NEXT, FIXED THE INTENTIONAL SYNTAX ERROR AND:

npm run serve

[email protected] serve /Users/R/Documents/Projects/Node/Adonis-Apps/test-app
node server.js

info adonis:framework +0ms serving app on localhost:3000
events.js:160
throw er; // Unhandled 'error' event
^

Error: listen EADDRINUSE 127.0.0.1:3000
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at Server._listen2 (net.js:1259:14)
at listen (net.js:1295:10)
at net.js:1405:9
at GetAddrInfoReqWrap.asyncCallback [as callback] (dns.js:62:16)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:81:10)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] serve: node server.js
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] serve script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /Users/R/.npm/_logs/2017-07-05T15_54_02_159Z-debug.log

What is annoying is that a code works perfectly fine, then you make a simple syntax error like above and it correctly crashes, but when you put the code back to its original working state it still crashes.

rezatrojan on 5 Jul 2017

Can u share the nodejs and npm version and the operating system you are on?

thetutlage on 5 Jul 2017

Sure:

macOS Sierra Version 10.12.3

node -v
v6.9.2

npm -v
5.0.4

P.S. I found a silly workaround: whenever I get stuck with occupied ports, I add a semicolon at the end of one of my variable declarations, and "usually" it puts the app back up and running, and next time I get stuck again with occupied ports I remove that semicolon and again it "usually" works!

rezatrojan on 5 Jul 2017

I am fresher at nodejs and was just building a basic project. I used nodemon, at first it worked perfectly but after few minutes it showed up this error in gitbash.
*Error: *
JASH PATEL@JASH MINGW64 /c/projects/nodekb
$ nodemon
[nodemon] 1.17.2
[nodemon] to restart at any time, enter rs
[nodemon] watching: .
[nodemon] starting node app.js
C:\projects\nodekb\app.js:18
{
^

SyntaxError: Unexpected token {
at createScript (vm.js:80:10)
at Object.runInThisContext (vm.js:139:10)
at Module._compile (module.js:616:28)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Function.Module.runMain (module.js:693:10)
at startup (bootstrap_node.js:188:16)
at bootstrap_node.js:609:3
[nodemon] app crashed - waiting for file changes before starting...

I've made an app.js file, whose contents are shown below...

*app.js : *
const express = require('express');
const path = require('path');
//init app
const app = express();
//load view engine
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');
//home route
app.get('/', function(req, res) {
let articles = [
{
id:1,
title:'article one',
body:'this is article one'
}
{
id:2,
title:'article two',
body:'this is article two'
}
{
id:3,
title:'article three',
body:'this is article three'
}
];
res.render('index', {
title:'Article',
articles: articles
});
});
//Add Routes
app.get('/articles/add', function(req, res) {
res.render('add_article', {
title:'Add Article'
});
});
//start server
app.listen(3000, function() {
console.log('server started on port 3000...!');
});