Javascript Error tracking is becoming more and more important, with applications moving to the client. Many service providers already offer a variety of extensive error tracking solutions for a price. These providers help to get around browser limitations and get the most out of errors.

Depending on your budget, that might not always be an option and not always needed.

To the rescue comes ErrorBoard, that provides a basic interface to track window.onerror events. Requires Node.js, NPM and a free port.

Here the window.onerror, how I set it up for now:

// checks if there was a previously defined window.onerror and preserve it
var oldOnError = window.onerror;

window.onerror = function( message, url, line, column, error ) {


  if (errorMsg.indexOf('Script error.') > -1) {
   return false;
  }
  
  try {
	var e = encodeURIComponent;
	
	var meta = '{"project":"portalzine.de"}';
	
	( new Image() ).src = 'http://UrltoErrorBoard/error?message=' + e( message ) +
	'&url='    	+ e( url ) +
	'&line='   	+ e( line ) +
	'&meta='	  	+ e( meta ) +
	( error && error.stack ? '&stack='   	+ e( error.stack ) : '' ) +
	( column ? '&column='  + e( column ) : '' )
	;
  
  } catch(e) {
  	// we don't want errors to throw inside onerror
  }
  
  // Call any previously assigned handler
  if (typeof oldOnError === 'function') {
  	oldOnError.apply(this, arguments);
  }
  
  // returning false triggers the execution of the built-in error handler								
  return false;
};

// checks if there was a previously defined window.onerror and preserve it

var oldOnError = window.onerror;

window.onerror = function( message, url, line, column, error ) {

if (errorMsg.indexOf('Script error.') > -1) {

return false;

}

try {

var e = encodeURIComponent;

var meta = '{"project":"portalzine.de"}';

( new Image() ).src = 'http://UrltoErrorBoard/error?message=' + e( message ) +

'&url=' + e( url ) +

'&line=' + e( line ) +

'&meta=' + e( meta ) +

( error && error.stack ? '&stack=' + e( error.stack ) : '' ) +

( column ? '&column=' + e( column ) : '' )

;

} catch(e) {

// we don't want errors to throw inside onerror

}

// Call any previously assigned handler

if (typeof oldOnError === 'function') {

oldOnError.apply(this, arguments);

}

// returning false triggers the execution of the built-in error handler

return false;

};

ErrorBoard – Track JS errors in a clean interface for yourself with node.js

Enjoy coding …

Alexander