Node HTTP Server EADDRINUSE - node.js

Question

I'm currently writing an mocha test for my project.
The test should cover the output of an ajax request and therefore I created a simple HTTP-Server with node.
This is the current code:
const http = require('http');
const server = http.createServer(function(req, res) {
res.write('test');
});
const port = 5555;
process.on('uncaughtException', function(err) {
console.log("Unhandled Exception, shutting down Server ...")
server.close();
console.log("Server closed!");
console.log(err);
process.exit(1);
});
process.on('SIGTERM', function() {
console.log("Termination called, shutting down Server ...");
server.close();
console.log("Server closed!");
process.exit(1);
});
server.listen('success', function(req, res) {
res.writeHead(200, {
"Content-Type": "application/json"
});
res.write(JSON.stringify({
success: true,
message: "Form success!"
}));
res.close();
});
server.listen('fail', function(req, res) {
res.writeHead(200, {
"Content-Type": "application/json"
});
res.write(JSON.stringify({
success: false,
message: "Form fail!"
}));
res.close();
});
server.listen(port);
console.log("Server running on Port: " + port);
Now for some reason it always throws me an EADDRINUSE error even when the port isn't used. I killed all node/nodejs processes (there weren't any), searched for the program which is using the port (lsof -i tcp:5555) which didn't send any back and even restarted the machine without any difference.
This is the output of the Terminal:
Server running on Port: 5555
Unhandled Exception, shutting down Server ...
Server closed!
{ Error: listen EADDRINUSE success
at Object.exports._errnoException (util.js:1022:11)
at exports._exceptionWithHostPort (util.js:1045:20)
at Server._listen2 (net.js:1249:19)
at listen (net.js:1298:10)
at Server.listen (net.js:1382:7)
at Object.<anonymous> (/home/dominik/Documents/workspace/jelly/test/test-server.js:23:8)
at Module._compile (module.js:571:32)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:488:32)
at tryModuleLoad (module.js:447:12)
code: 'EADDRINUSE',
errno: 'EADDRINUSE',
syscall: 'listen',
address: 'success',
port: -1 }
npm ERR! Test failed. See above for more details.
I tried to search for solutions already of course, but all I find is kill the server with the same commands. Thanks in advance

Answer 1

You are not using the http module correctly. With the statement server.listen('success',...) you are starting a UNIX socket server on the socket "success" which makes no sense.
Below is an example where the http server returns different responses based in the requested url. I recommend reading this tutorial.
const http = require('http');
const server = http.createServer(function (req, res) {
res.writeHead(200, {
'Content-Type': 'application/json',
});
var responseBody = {};
if (req.url === '/success') {
responseBody = {
success: true,
message: "Form success!"
};
}
if (req.url === '/fail') {
responseBody = {
success: false,
message: "Form fail!"
};
}
res.write(JSON.stringify(responseBody));
res.end();
});
const port = 5555;
process.on('uncaughtException', function (err) {
console.log("Unhandled Exception, shutting down Server ...")
server.close();
console.log("Server closed!");
console.log(err);
process.exit(1);
});
process.on('SIGTERM', function () {
console.log("Termination called, shutting down Server ...");
server.close();
console.log("Server closed!");
process.exit(1);
});
server.listen(port, function () {
console.log("Server running on Port: " + port);
});
Test:
curl http://localhost:5555/success
curl http://localhost:5555/fail