Tips and Tricks¶
These are some general recommendations and tips for how to get the most out of Raven.js and Sentry.
Decluttering Sentry¶
The first thing to do is to consider constructing a whitelist of domains in which might raise acceptable exceptions.
If your scripts are loaded from cdn.example.com
and your site is
example.com
it’d be reasonable to set whitelistUrls
to:
whitelistUrls: [
/https?:\/\/((cdn|www)\.)?example\.com/
]
Since this accepts a regular expression, that would catch anything *.example.com or example.com exactly. See also: Config: whitelistUrls.
Next, checkout the list of integrations we provide and see which are applicable to you.
The community has compiled a list of common ignore rules for common things, like Facebook, Chrome extensions, etc. So it’s recommended to at least check these out and see if they apply to you. Check out the original gist.
var ravenOptions = {
ignoreErrors: [
// Random plugins/extensions
'top.GLOBALS',
// See: http://blog.errorception.com/2012/03/tale-of-unfindable-js-error. html
'originalCreateNotification',
'canvas.contentDocument',
'MyApp_RemoveAllHighlights',
'http://tt.epicplay.com',
'Can\'t find variable: ZiteReader',
'jigsaw is not defined',
'ComboSearch is not defined',
'http://loading.retry.widdit.com/',
'atomicFindClose',
// Facebook borked
'fb_xd_fragment',
// ISP "optimizing" proxy - `Cache-Control: no-transform` seems to
// reduce this. (thanks @acdha)
// See http://stackoverflow.com/questions/4113268
'bmi_SafeAddOnload',
'EBCallBackMessageReceived',
// See http://toolbar.conduit.com/Developer/HtmlAndGadget/Methods/JSInjection.aspx
'conduitPage'
],
ignoreUrls: [
// Facebook flakiness
/graph\.facebook\.com/i,
// Facebook blocked
/connect\.facebook\.net\/en_US\/all\.js/i,
// Woopra flakiness
/eatdifferent\.com\.woopra-ns\.com/i,
/static\.woopra\.com\/js\/woopra\.js/i,
// Chrome extensions
/extensions\//i,
/^chrome:\/\//i,
// Other plugins
/127\.0\.0\.1:4001\/isrunning/i, // Cacaoweb
/webappstoolbarba\.texthelp\.com\//i,
/metrics\.itunes\.apple\.com\.edgesuite\.net\//i
]
};
Sampling Data¶
It happens frequently that errors sent from your frontend can be
overwhelming. One solution here is to only send a sample of the events
that happen. You can do this via the shouldSendCallback
setting:
shouldSendCallback: function(data) {
// only send 10% of errors
var sampleRate = 10;
return (Math.random() * 100 <= sampleRate);
}
jQuery AJAX Error Reporting¶
For automatically reporting AJAX errors from jQuery, the following tips might be helpful, however depending on the type of request you might have to do slightly different things.
Same Origin¶
Whenever an Ajax request completes with an error, jQuery triggers the
ajaxError
event, passing the event
object, the jqXHR
object
(prior to jQuery 1.5, the XHR
object), and the settings
object
that was used in the creation of the request. When an HTTP error occurs,
the fourth argument (thrownError
) receives the textual portion of the
HTTP status, such as “Not Found” or “Internal Server Error.”
You can use this event to globally handle Ajax errors:
$(document).ajaxError(function(event, jqXHR, ajaxSettings, thrownError) {
Raven.captureMessage(thrownError || jqXHR.statusText, {
extra: {
type: ajaxSettings.type,
url: ajaxSettings.url,
data: ajaxSettings.data,
status: jqXHR.status,
error: thrownError || jqXHR.statusText,
response: jqXHR.responseText.substring(0, 100)
}
});
});
Note:
- This handler is not called for cross-domain script and cross-domain JSONP requests.
- If
$.ajax()
or$.ajaxSetup()
is called with theglobal
option set tofalse
, the.ajaxError()
method will not fire. - As of jQuery 1.8, the
.ajaxError()
method should only be attached to document.
Cross Origin¶
Due to security reasons most web browsers are not giving permissions to access error messages for cross domain scripts. This is not jQuery issue but an overall javascript limitation.
Depending on your situation you have different options now:
When you control the backend¶
If you have access to the backend system you are calling, you can set response headers to allow a cross domain call:
Access-Control-Allow-Origin: *
Script tags have now got a new non-standard attribute called
crossorigin
(read more).
The most secure value for this would be anonymous
. So, you’ll have to
modify your script tags to look like the following:
<script src="http://sub.domain.com/script.js" crossorigin="anonymous"></script>
When you have no access to the backend¶
If you have no access to the backend, you could try a workaround, which is basically adding a timeout on the Ajax call. This is however very dirty, and will fail on slow connection or long response time:
$.ajax({
url: 'http:/mysite/leaflet.js',
success: function() { ... },
error: function() { ... },
timeout: 2000, // 2 seconds timeout before error function will be called
dataType: 'script',
crossDomain: true
});