How to check connection error in mongojs

[rohittailor]

Hi,

How to check connection error in mongojs. When we run the app and mongodb is up than its working fine. When we stop mongodb, it throws an exception. Can we handle connection errors in mongojs ?

[rohittailor]

Getting following error:

events.js:72
throw er; // Unhandled 'error' event
^
Error: failed to connect to [127.0.0.1:27017]
at null. (C:\Rohit\Research\No
at EventEmitter.emit (events.js:106:17)
at null. (C:\Rohit\Research\No
at EventEmitter.emit (events.js:98:17)
at Socket. (C:\Rohit\Research
at Socket.EventEmitter.emit (events.js:95
at net.js:440:14
at process._tickCallback (node.js:415:13)

[sorribas]

Hello @rohittailor

You can do something like this.

var mongojs = require('mongojs');
var db = mongojs('test', ['a']);

...

db.on('error', function() {
  console.log('we had an error.');
});

And then it shouldn't throw. Let me know if you have any more problems.

[rohittailor]

Hi Sorribas,

I implemented that code and its working when mongodb up and we stop mongodb. But when mongodb is not running than i am getting same error and its not going in error callback.

Please help.

Thanks,
Rohit

[sorribas]

It's true that it doesn't emit the error when the database is not running (we'll fix that), but I don't get the error thrown. What version of mongojs are you running?

[ghost]

Hi Sorribas,

Is this the same issue - ie on startup if the database doesn't exist I'm not getting an an error?

var mongojs = require('mongojs');
var db = mongojs('nonexistentdb', ['a']);

...

db.on('error', function() {
  console.log('we had an error.');
});

Above error not being logged if connection fails.

Many thanks,
Ben

[bluedusk]

Hi , I ran into this same problem with mongojs 1.3.0 on Windows 7 , I cant get any event when mongodb is not running or when I stop it.

var mongojs = require('mongojs');
var db = mongojs('test', ['a']);

db.on('error', function() {
  console.log('we had an error.');
});

[Sparragus]

I have the same issue as @bluedusk. If I don't have a mongodb server running, the app simply fails silently and exits. It should emit the error event or throw. It does neither.

Specs:
OSX 10.10.5
node v2.2.1
mongojs 1.3.0
mongodb v3.0.6

[sergiolc]

I have the same issue as @Sparragus.

mongojs 1.3.0

[julio-coelho]

Same here. If the server was not running on 'connect', no error is thrown.
A callback function would be nice.

[imjul1an]

same here.

[rafajaw]

Is it going to be fixed? it's a showstopper for me. I saw some topic saying to use a connectionTimeout parameter like this:

var db  =  mongojs( db_conn, ['bots'], {connectionTimeout: 3000} );
db.on('timeout', function (err) {
    console.log('database timeout');
});

but it is still not working.

[iMoses]

Nothing worse than finding the issue you're struggling with in github only to discover it should have been fixed a year ago :)

[saintedlama]

In version 2.0.0 you can register an error event listener with

var db  =  mongojs( db_conn, ['bots'], {connectionTimeout: 3000} );
db.on('error', function (err) {
    console.log('Connection errored', err);
});

[amado-saladino]

That did not work for me, it throws the error and logged (app crashed)