jserrlogger

A javascript module that catches javascript errors and posts them back to a server to be logged and managed.

Including jserrlogger.js

Add a script tag to your page

<script src="jserrlogger.min.js"></script>

Install the handler

<script>
    jserrlogger.install("http://www.your-url.com/err_js_endpoint");
</script>

Install the handler with options

<script>
    var options = {
        upperLimit: 5,
        debug: 1,
        timeout: 3000
    };
    jserrlogger.install("http://www.your-url.com/err_js_endpoint", options);
</script>

Options available to specify:

• upperLimit - when set, only report the first upperLimit errors in one browser session, ignore any errors after that
• debug - when enabled, log to console any errors
• timeout - timeout after which the jsonp script is removed from the DOM (in ms)

Implement the server side endpoint

jserrlogger will send GET requests like these:

http://www.your-url.com/err_js_enpoint/?i=1&sn=<encoded_page_url>&fl=<encoded_js_file_name>&ln=<line_number>&err=<encoded_err_message>

Handle it on the server side as you see fit (i.e. log them in a DB, email them, etc.)

You can report your own errors

Use jserrlogger.logErr call to report your own errors to the server side.

    jserrlogger.logErr("Someone stepped on the boobytrap.", "app.js", 834);

How does it work?

jserrlogger.js installs a callback on window.onerror. This is a callback that gets called whenever there's a javascript error on a page (which is not caught). These errors can come up from your code or any 3rd party js libraries you use. jserrlogger.js will then submit a JSONP request to your configured URL endpoint (the one you specify in the call to install) and send you in the query string:

• i - an enumerator of the exception since the start of the browser session (0 - first, etc.)
• sn - the URL of the page as shown in the browser where the exception was raised
• fl - the js file name where the exception was raised
• ln - the line number where the exception was raised
• err - the actual message of the exception raised

jserrlogger.js will also call any previously installed window.onerror callback.