Restart node.js

Question

I'm just approaching node.js , so I'm running the obvious example - in a file called server.js :

var http = require("http");

function onRequest(request, response) {
    response.writeHead(200, {"Content-Type": "text/plain"});
    response.write("it's alive!");
    response.end();
}

http.createServer(onRequest).listen(8888);

I run this from terminal with node server.js and all it's ok, server responds.

But when I need to change the server.js :

• I made my changes on file;
• write again node server.js ;

server responds me with the following error:

events.js:141
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE :::8888
    at Object.exports._errnoException (util.js:870:11)
    at exports._exceptionWithHostPort (util.js:893:20)
    at Server._listen2 (net.js:1237:14)
    at listen (net.js:1273:10)
    at Server.listen (net.js:1369:5)
    at Object.<anonymous> (/var/www/vhosts/lizardhq.com/httpdocs/server.js:9:30)
    at Module._compile (module.js:410:26)
    at Object.Module._extensions..js (module.js:417:10)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)

what I'm doing wrong? Many thanks.

Answer 1

The error you encounter means your server was not properly shutdown, or is still shutting down, and the port he's listening on is still in use.

You could wait a few minutes for the port to become available, or, if you are using linux, you could find the process id ( PID ) that is using the port via lsof | grep 8888 lsof | grep 8888 which will give you a PID in the second column, and then kill it via kill -9 PID .

You could also use supervisor and npm to watch for change to your file system, and restart your server automagically:

Install supervisor :

npm install supervisor -g

Then, in your package.json file, add this line:

"scripts": {
    "start": "supervisor -w 'server.js' node server.js"
},

Now, start your server using the following command:

npm start

Now, every time you save the server.js file, your server will restart automaticaly. No more EADDRINUSE error !

Answer 2

This error means you've already got a Node.js server (or some other server) running on port 8888 . You need to STOP your other process which is using that port before you can start your Node server on the same port =)

Only one program can bind to a port at a time.

Answer 3

sometimes it happens to me, open the task manager | ps -a depending system and kill node process