I’m running a Django-powered site for a closed user group and added a bit of JavaScript magic here and there (mainly Prototype and Tooltip).

Now Django sends me a mail whenever a 404 or 500 error occurs. But when one of my users encounters a JavaScript-Error, I’m not informed. I thought anyone in the web has solved this problem but didn’t find anything, so here’s my take: Just send any error using Ajax (here: using Prototypes Ajax abstraction) to the server

onerror = Extranet.mailError;
function mailError(msg, url, line) {
 var postBody = 'url=' + url + '&line=' + line + '&message=' + escape(msg) + '&useragent=' + escape(navigator.userAgent) + '&user=' + escape(user_name);
 var myAjax = new Ajax.Request('/api/jserror/', {method: 'post', postBody: postBody});

user_name is a JavaScript variable holding the Django username (so I know whom I can inform when the error is fixed).

On the server side, I just send me mails containing the JavaScript error message, the username and the user agent:

def jserror(request):
 from django.core.mail import mail_admins
 omit_messages = ['pointerobj is not defined', 'tipobj is not defined', 'ns6 is not defined', 'enabletip is not defined']
 if request.POST.get('message', '') not in omit_messages:
  message = """url: %s (%s)
user-agent: %s
username: %s
""" % (request.POST.get('url', ''), request.POST.get('line', ''), request.POST.get('message', ''), request.POST.get('useragent', ''), request.POST.get('user', ''))
  mail_admins("javascript error", urldecode(message))
 return HttpResponse()

Yeah, that’s all very trivial but I wonder what other solutions exist for this problem…