Error with NodeJS - node.js

I have this error when i try run my script.
{ [Error: listen EADDRINUSE :::8000]
code: 'EADDRINUSE',
errno: 'EADDRINUSE',
syscall: 'listen',
address: '::',
port: 8000 }
Error: listen EADDRINUSE :::8000
at Object.exports._errnoException (util.js:890:11)
at exports._exceptionWithHostPort (util.js:913:20)
at Server._listen2 (net.js:1234:14)
at listen (net.js:1270:10)
at Server.listen (net.js:1366:5)
at Server.listen.Server.attach (/usr/lib/node_modules/socket.io/lib/index.js:216:9)
at Timeout._onTimeout (/var/www/html/Bot/site.js:618:29)
at tryOnTimeout (timers.js:224:11)
at Timer.listOnTimeout (timers.js:198:5)
Script.js around ~605 Line
function load() {
query('SET NAMES utf8');
query('SELECT `id` FROM `rolls` ORDER BY `id` DESC LIMIT 1', function(err, row) {
if((err) || (!row.length)) {
logger.error('Cant get number from the last game');
logger.debug(err);
process.exit(0);
return;
}
currentRollid = row[0].id;
logger.trace('Roll '+currentRollid);
});
loadHistory();
setTimeout(function() { io.listen(8080); }, 3000);
}
618 line is
setTimeout(function() { io.listen(8080); }, 3000);
How i can fix this ? I try change io.listen Port but its still dont work.

Firstly, you should know that the EADDRINUSE error, gets thrown whenever the port that you're trying to listen on, is already in-use.
To fix this problem, you're going to need to free-up the port that your application is trying to listen on (if you're using Linux, perhaps you'll find this StackOverflow thread to be of use).
When creating servers in NodeJS, it's generally a good idea to listen for [process] exit events, so you can close your server, thus freeing up the port that it's listening on.
Here's some great documentation that provides information about different events that can be fired before a NodeJS process is terminated:
process_event_exit
process_event_uncaughtexception
process_signal_events
Going based on the snippets that you provided, I'm making the assumption that you're using SocketIO.
This StackOverflow answer gives a great example about how to close a SocketIO server.

Related

How to fix 'events.js :167 error Error: connect ECONNREFUSED 127.0.0.1:443' in Node.js when no other apps seems to be attempting to use the port?

I'm getting the error described below when running my node.js app after perfoming a few api calls.
The error does not always show in the exactly same place/line of code. But most of the times it is at the end of the api call.
events.js:167
throw er; // Unhandled 'error' event
^
Error: connect ECONNREFUSED 127.0.0.1:443
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1113:14)
Emitted 'error' event at:
at TLSSocket.socketErrorListener (_http_client.js:391:9)
at TLSSocket.emit (events.js:182:13)
at emitErrorNT (internal/streams/destroy.js:82:8)
at emitErrorAndCloseNT (internal/streams/destroy.js:50:3)
at process._tickCallback (internal/process/next_tick.js:63:19)
Based on similar questions here at SO my hypothesis is that a) there is something using 127.0.0.1:443 and therefore conflicting with my app or b) node is trying to use 127.0.0.1:443 but there is nothing there for it to use (my app is listening to localhost :3000).
Hyphothesis a) doesn't seem likely since after running netstat -ano | findstr 127.0.0.1:443 nothing shows up (when app is running and right after it terminates).
Also killed every node.exe and mongod.exeb using any port in my computer, closed the terminal and restarted the node app without success.
In case error is related with hypothesis b) I'm not sure how to address it.
api.post('/parsePOpdf', wagner.invoke(function(Pdfeq, Pdfdocspec, Product, User, Order){
return async function(req,res){
//... some code
pdfParser.on("pdfParser_dataError", errData => console.error(errData.parserError) );
pdfParser.on("pdfParser_dataReady", async function(pdfData) {
fs.writeFile("./test.json", JSON.stringify(pdfData), function(err){
console.log(err);
});
let pages = pdfData.formImage.Pages;
//console.log('pages 557', pages);
let order = {
orderDetails : {
supplier : [{
item : []
}]
}
};
for (const page of pages){
let value = await getItemsInPDF(page, productKeys, pdfParsingDetails, order, Product, customer, supplierLink, User);
//... more code
order = value;
}
return res.json(order);
});
pdfParser.loadPDF(pdfFile);
}
}));
I would expect the code to finish without throwing this error.
It turns out that the problem was in the api code: an http.get line to fetch a remote file was generating the conflict. This makes sense since the error was not present for other endpoints of the api.
So learning is that if the terminal reports no app using the suspected conflicting port (see question) answser should be within the same code and you need to go line by line to identify which one is causing the problem (instead of focusing on other apps trying to use the same port, like I was focusing on).

How to track down error in node network code?

I am trying to track down why my code is failing with this error:
{ Error: connect ECONNREFUSED 127.0.0.1:443
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1082:14)
errno: 'ECONNREFUSED',
code: 'ECONNREFUSED',
syscall: 'connect',
address: '127.0.0.1',
port: 443 }
and the stack trace for that error looks like this:
Error: connect ECONNREFUSED 127.0.0.1:443
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1082:14)
I am making a network connection, but I am not trying to connect to localhost.
The network code I am using works just fine (and connects to the right host) in other contexts.
I'm using node 11.6.0 as supplied by brew install, and it looks like the only occurrence of the string "net.js" in the brew "Cellar" directory structure is in the node binary itself. In other words, even after
brew install --build-from-source node
running
find /usr/local/Cellar/node/11.6.0 -type f | xargs fgrep -l net.js
only finds one file: /usr/local/Cellar/node/11.6.0/bin/node and there's no net.* files in that directory tree.
If it matters, my code which seems to trigger this error looks like this:
const get_json_with_auth= async (channel, url) => {
const parsed_url= URL.parse(url);
return new Promise((good, fail) => {
let request= require('https').get({
hostname: parsed_url.hostname,
path: parsed_url.path,
headers: {
Authorization: get_auth('GET', channel, url)
}
});
console.log('url', url);
request.on('response', response=> {
const chunks= [];
response.on('data', data=> chunks.push(data));
response.on('end', ()=> good(JSON.parse(Buffer.concat(chunks).toString())));
});
request.on('error', err=> fail(err));
});
};
(I'm on OSX high sierra here.)
But, once again, the host name in the url I'm using does not resolve to localhost (and works just fine in other contexts).
How do I isolate a problem like this?
Running my code with the environmental variable NODE_DEBUG='net,tls,http,https' gave me enough information to recognize (and isolate) the problem.

Socket.io EADDRNOTAVAIL error

I oppened port of 120 on my firewall and i open ufw port on my server (Ubuntu 16.04)
But when run this code ;
var app = require('express')();
var http = require( "http" ).createServer( app );
var io = require( "socket.io" )( http );
http.listen(120, "xxxx.xxx.xx");
io.on('connection',function(socket){
console.log("A user is connected");
});
I get this error ;
throw er; // Unhandled 'error' event
^
Error: listen EADDRNOTAVAIL xxxx.xxxxxx:120
at Object.exports._errnoException (util.js:870:11)
at exports._exceptionWithHostPort (util.js:893:20)
at Server._listen2 (net.js:1224:19)
at listen (net.js:1273:10)
at net.js:1382:9
at nextTickCallbackWith3Args (node.js:452:9)
at process._tickCallback (node.js:358:17)
at Function.Module.runMain (module.js:444:11)
at startup (node.js:136:18)
at node.js:966:3
It may be that port 120 is already being used by something else.
You can use netstat to see what is listening on that port:
sudo netstat -plnt | grep ':120'
Another thing to mention is that low ports are sometimes reserved or blocked - you may want to just try a higher port, '1337' is always good for NodeJS :-)

node.js - handling TCP socket error ECONNREFUSED

I'm using node.js with socket.io to give my web page access to character data served by a TCP socket. I'm quite new to node.js.
User ----> Web Page <--(socket.io)--> node.js <--(TCP)--> TCP Server
The code is mercifully brief:
io.on('connection', function (webSocket) {
tcpConnection = net.connect(5558, 'localhost', function() {});
tcpConnection.on('error', function(error) {
webSocket.emit('error', error);
tcpConnection.close();
});
tcpConnection.on('data', function(tcpData) {
webSocket.emit('data', { data: String.fromCharCode.apply(null, new Uint8Array(tcpData))});
});
});
It all works just fine in the normal case, but I can't guarantee that the TCP server will be there all the time. When it isn't, the TCP stack returns ECONNREFUSED to node.js - this is entirely expected and I need to handle it gracefully. Currently, I see:
events.js:72
throw er; // Unhandled 'error' event
^
Error: connect ECONNREFUSED
at errnoException (net.js:904:11)
at Object.afterConnect [as oncomplete] (net.js:895:19)
... and the whole process ends.
I've done a lot of searching for solutions to this; most hits seem to be from programmers asking why ECONNREFUSED is received in the first place - and the advice is simply to make sure that the TCP server is available. No discussing of handling failure cases.
This post - Node.js connectListener still called on socket error - suggests adding a handler for the 'error' event as I've done in the code above. This is exactly how I would like it to work ... except it doesn't (for me), my program does not trap ECONNREFUSED.
I've tried to RTFM, and the node.js docs at http://nodejs.org/api/net.html#net_event_error_1 suggest that there is indeed an 'error' event - but give little clue how to use it.
Answers to other similar SO posts (such as Node.js Error: connect ECONNREFUSED ) advise a global uncaught exception handler, but this seems like a poor solution to me. This is not my program throwing an exception due to bad code, it's working fine - it's supposed to be handling external failures as it's designed to.
So
Am I approaching this in the right way? (happy to admit this is a newbie error)
Is it possible to do what I want to do, and if so, how?
Oh, and:
$ node -v
v0.10.31
I ran the following code:
var net = require('net');
var client = net.connect(5558, 'localhost', function() {
console.log("bla");
});
client.on('error', function(ex) {
console.log("handled error");
console.log(ex);
});
As I do not have 5558 open, the output was:
$ node test.js
handled error
{ [Error: connect ECONNREFUSED]
code: 'ECONNREFUSED',
errno: 'ECONNREFUSED',
syscall: 'connect' }
This proves that the error gets handled just fine... suggesting that the error is happening else-where.
As discussed in another answer, the problem is actually this line:
webSocket.emit('error', error);
The 'error' event is special and needs to be handled somewhere (if it isn't, the process ends).
Simply renaming the event to 'problem' or 'warning' results in the whole error object being transmitted back through the socket.io socket up to the web page:
webSocket.emit('warning', error);
The only way I found to fix this is wrapping the net stuff in a domain:
const domain = require('domain');
const net = require('net');
const d = domain.create();
d.on('error', (domainErr) => {
console.log(domainErr.message);
});
d.run(() => {
const client = net.createConnection(options, () => {
client.on('error', (err) => {
throw err;
});
client.write(...);
client.on('data', (data) => {
...
});
});
});
The domain error captures error conditions which arise before the net client has been created, such as an invalid host.
See also: https://nodejs.org/api/domain.html

running Hook.io on a different port

I tried to run hook.io with a different port, which killed the autodiscover features of the clients. But when I try to create the clients with the same port, they get an error.
Sever:
var oHook = hookio.createHook( {
'name' :'dispatch-hook',
'hook-port': 9999,
'hook-host': 'localhost'
} );
oHook.start();
Client:
var oHook = hookio.createHook( {
name :'client-hook',
"hook-port":9999,
"hook-host":'localhost'
});
oHook.connect();
Error:
events.js:66
throw arguments[1]; // Unhandled 'error' event
^
Error: listen EADDRINUSE
at errnoException (net.js:781:11)
at Server._listen2._connectionKey (net.js:922:26)
at process.startup.processNextTick.process._tickCallback (node.js:244:9)
Why does the client want to start a server?
You shouldn't provide a port for the hook trying to connect to the server hook. The existence of hook-port in options makes that hook a server

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