When a remote site is off-line I am getting this error in my consuming client (Node.js v0.12.0 with the http module):
Uncaught exception: connect ECONNREFUSED
Error: connect ECONNREFUSED
at exports._errnoException (util.js:746:11)
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:983:19)
The code I'm currently using looks like this:
var req = http.request(options, function (res) {
res.on('socket', function (socket) {
socket.setKeepAlive(true, 0);
socket.setNoDelay(true);
});
res.on('end', function () {
log.debug('Success');
}).on('error', function () {
log.error('Response parsing failed');
});
}).on('error', function () {
log.error('HTTP request failed');
});
req.write(packet);
req.end();
The "error" event is never fired when the ECONNREFUSED occurs, I've tried using the "clientError" event but this is not fired either.
How can I capture this error?
Extracted from: https://stackoverflow.com/a/4328705/4478897
NOTE: This post is a bit old
The next example is with the http.createClient but i think it could be the same
Unfortunately, at the moment there's no way to catch these exceptions directly, since all the stuff happens asynchronously in the background.
All you can do is to catch the uncaughtException's on your own:
process.on('uncaughtException', function (err) {
console.log(err);
});
Maybe that helps you!
More this: https://stackoverflow.com/a/19793797/4478897
UPDATE:
did you tried to change log.error() to console.error() ???
Related
The following code causes an error when there is no existing TCP server to communicate with on the specified host:
const net = require('net');
const argv = require('minimist')(process.argv.slice(2));
try {
var tcpSocket = new net.Socket();
tcpSocket.connect(argv.tcpport, argv.tcphost, function onConnected() {
console.log('connected');
tcpSocket.on('data', function onIncoming(data) {
console.log(data);
});
tcpSocket.on('close', function onClose(data) {
tcpSocketConnected = false;
});
tcpSocketConnected = true;
});
} catch (err) {
console.log("PRINT ME: ", err);
}
Error:
events.js:183
throw er; // Unhandled 'error' event
^
Error: connect ECONNREFUSED 127.0.0.1:1906
at Object._errnoException (util.js:992:11)
at _exceptionWithHostPort (util.js:1014:20)
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1186:14)
I am unable to catch the error even though I wrap the code in a try...catch.
Why does my catch block not catch the error?
How can I gracefully handle the error?
You should be able to explicitly handle the error event using event emitter api (same way as you handled close and data):
tcpSocket.on('error', handleError)
From Docs:
Event: 'error'#
Added in: v0.1.90
<Error>
Emitted when an error occurs. Unlike net.Socket, the 'close' event
will not be emitted directly following this event unless server.close()
is manually called. See the example in discussion of server.listen().
In my express app i have the route below:
router.get('/generatedData', function (req, res) {
res.setHeader('Connection' , 'Transfer-Encoding');
res.setHeader('Content-Type' , 'text/html; charset=utf-8');
res.setHeader('Transfer-Encoding' , 'chunked');
var Client = someModule.client;
var client = Client();
client.on('start', function() {
console.log('start');
});
client.on('data', function(str) {
console.log('data');
res.write(str);
});
client.on('end', function(msg) {
client.stop();
res.end();
});
client.on('err', function(err) {
client.stop();
res.end(err);
});
client.on('end', function() {
console.log('end');
});
client.start();
});
On first call everything works fine (console)
We've got ourselves a convoy on port 3000
start
data
data
data
data
data
...
data
end
GET /generatedData 200 208.426 ms - -
I get all the data and res.end() is being called and successfully closes the request.
The problem starts after first request. I make the exact same request (new one of course) and i get the following error (console):
start
data
data
data
events.js:160
throw er; // Unhandled 'error' event
^
Error: write after end
at ServerResponse.OutgoingMessage.write (_http_outgoing.js:439:15)
at Client.<anonymous> (/Users/xxxx/projects/xxxx/routes/index.js:33:17)
at emitOne (events.js:96:13)
at Client.emit (events.js:188:7)
at FSWatcher.<anonymous> (/Users/xxxx/projects/xxxx/lib/someModule.js:116:32)
at emitTwo (events.js:106:13)
at FSWatcher.emit (events.js:191:7)
at FSEvent.FSWatcher._handle.onchange (fs.js:1412:12)
[nodemon] app crashed - waiting for file changes before starting...
This happens without res.end() being called.
I manage to get some data before the crash.
How can i get this error without res.end() being called at all?
Do i somehow save the previous res instance?
Thanks,
Asaf
Have the same problem. My module was extened by EventEmitter and each time i catch event in router - it stays there, end on second call there are two eventlisteners not one. Setting "once" instead of "on" - worked for me.
client.once('start', function() {
console.log('start');
});
instead of
client.on('start', function() {
console.log('start');
});
And then when adding a stream, I try to catch an occurring error:
try {
logger.addStream(stream); // ERROR HAPPENS AT THIS CALL
console.info(`TRY activated`);
} catch (e) {
console.error(e);
}
I do get the TRY activated message, but the app still crashes. This leads me to the thought that the async model prevents the try-catch to work here.
I added a callback to the addStream() as follows:
logger.addStream(stream, (err, stream) => {
console.log(err);
});
but this doesn't help either.
Also tried with logger.on('error', (err, stream) => { console.log(err) }); but unsuccessful as well.
I'm getting a getaddrinfo ENOTFOUNDerror:
/app/node_modules/gelf/gelf.js:95
throw err;
^
Error: getaddrinfo ENOTFOUND graylog-server
at errnoException (dns.js:28:10)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:76:26)
Can I catch that locally? F.e. without adding uncaughtException to my process, etc...
I use "net" library to create TCP connection on my nodeJs.
root.socket = net.createConnection(root.config.port, root.config.server);
I'm trying to handle error when remote server is down and reconnect in Cycle.
root.socket.on('error', function(error) {
console.log('socket error ' + error);
root.reconnectId = setInterval(function () {
root.socket.destroy();
try {
console.log('trying to reconnect');
root.socket = net.createConnection(root.config.port, root.config.server);
} catch (err) {
console.log('ERROR trying to reconnect', err);
}
}, 200);
}
The trouble is that in case of remote server shutdown I still get en error and my nodeJS server stops.
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)
You will need something like this:
var net = require('net');
var c = createConnection(/* port, server */);
function createConnection(port, server) {
c = net.createConnection(port, server);
console.log('new connection');
c.on('error', function (error) {
console.log('error, trying again');
c = createConnection(port, server);
});
return c;
}
In your case you are creating a new connection but you don't attach any error listener, the error is raised somewhere else in the execution loop and can not be caught by the "try / catch" statement.
P.S. try to avoid using "try / catch" statement, error handling in Node.JS is made using error listeners and domains, it can be useful only for JSON.parse() or other functions that are executed synchronously.
I have a node app that posts data to remote apis and fetches the responses. It works fine but at times the node server crashes and generates the following errror:
events.js:71
throw arguments[1]; // Unhandled 'error' event
^
Error: socket hang up
at createHangUpError (http.js:1264:15)
at Socket.socketCloseListener (http.js:1315:23)
at Socket.EventEmitter.emit (events.js:126:20)
at Socket._destroy.destroyed (net.js:358:10)
at process.startup.processNextTick.process._tickCallback (node.js:244:9)
I googled and found that it happens due to some timeout thing but i am not really sure as to how to overcome this.
Here is the required code in my server.js:
if(request.body.company=="CQ")
{
var postData={firstName:request.body.firstname,lastName:request.body.lastname,Email:request.body.email,DayPhoneNumber:request.body.daytimePhone,Address1:request.body.addressOne,city:request.body.city,state:request.body.State,postalCode:request.body.zip,AreaOfIntrest:request.body.areaOfInterest,VendorLocationId:"38404",Notes:request.body.Notes,GraduationYear:request.body.graduationYear,AffiliateLocationId:"12345",LocationId:"12345",CampaignId:"12345"};
var options={hostname:'webservices.someapi.com', path:'/ILM/Default.ashx?'+qs.stringify(postData), method:'GET'};
var req = http.request(options, function(res) {
res.on('data', function (chunk) {
edModel.find({$and:[{daytimePhone:request.body.daytimePhone},{company:"CQ"}]},function(err,count){
if(count.length==0)
{
var sr='RESPONSE: ' + chunk;
if(sr.indexOf('status="Error"')==-1)
{
request.body.leadid=sr;
var sr=sr.slice(sr.indexOf("leadid"));
sr=sr.slice(0,sr.indexOf(">"));
edDoc=new edModel(request.body);
edDoc.save();
response.send({response:sr});
}
else
{
response.send({response:sr});
}
}
else
{
response.send({response:"<span style='color:red'>Duplicate Lead.<br> A lead with this number already exists in our database</span>"});
}
});
});
});
// write data to request body
req.write('data\n');
req.end();
}
I have several such if else conditions in the server.js file.
in node 0.8.20 there was a bug about that problem. try using http.get instead of http.request. or just dont use 0.8.20 if you use that version.