Wait for matomo request to finish (Callback/Event?)

chr1d · May 10, 2022, 8:10am

Is there a callback I can use to see if trackPageView has been executed?
Reason: I am changing the url to remove GET-Parameters such as fbclid, but I don’t want to remove them before the page view has been tracked. If I remove them before, then Matomo will track the “clean” url.

Thanks!

Lukas · May 10, 2022, 9:36am

The third parameter of trackPageView should be exactly this:

github.com

matomo-org/matomo/blob/0f89a53f82d1d0d50cd1e22773be9321256bbe93/js/piwik.js#L6388

      
        
                return numTrackedPageviews;
            };
            
            
/**
             * Log visit to this page
             *
             * @param string customTitle
             * @param mixed customData
             * @param function callback
             */
            this.trackPageView = function (customTitle, customData, callback) {
                trackedContentImpressions = [];
                consentRequestsQueue = [];
                javaScriptErrors = [];
            
            
    if (isOverlaySession(configTrackerSiteId)) {
                    trackCallback(function () {
                        injectOverlayScripts(configTrackerUrl, configApiUrl, configTrackerSiteId);
                    });
                } else {
                    trackCallback(function () {

chr1d · May 10, 2022, 12:12pm

Thanks! I found this as well, but how is it possible to use this with

_paq.push(['trackPageView']);

I tried the following, which doesn’t work though

_paq.push(['trackPageView', undefined, function() { console.log("hi"); }]);
_paq.push(['trackPageView', { callback: foobar }]); // also doesnt work

heurteph-ei · May 10, 2022, 12:38pm

Lukas mentioned the callback as the 3rd argument, but in your 1st example you used it as the 2nd one…

chr1d · May 10, 2022, 1:04pm

Ahh, of course, ‘trackPageView’ is not the 1st parameter
Thanks guys!

utrautma · September 20, 2023, 1:41pm

Hi,
I want to reopen this discussion.

I’m not sure about the callback event and how it works:

I have a requirement to create a new visit and track an event immediately afterwards.
If use the trackPageView callback, the event is often added to the previous visit.

if(loggedOut){
_paq.push(['appendToTrackingUrl', 'new_visit=1']); // erzwinge einen neuen Besuch
_paq.push(['trackPageView',undefined,undefined,function(){
     _paq.push(['appendToTrackingUrl', '']); // do not force a new visit anymore (only do it once)
	 _paq.push(['trackEvent', 'Portal', 'User logged out']);}]);

}

If I delay the trackEvent call, it works, but I’m not entirely comfortable with the idea because Matomos trackPageView could of course not be finished with the delay if there is a load peak.

if(loggedOut)[
_paq.push(['appendToTrackingUrl', 'new_visit=1']); // erzwinge einen neuen Besuch
_paq.push(['trackPageView']);
setTimeout(function() {
					//delay after trackPageView
					_paq.push(['appendToTrackingUrl', '']); // do not force a new visit anymore (only do it once)
					_paq.push(['trackEvent', 'Portal', 'User logged out']);
				}, 1500);
   
}

heurteph-ei · September 21, 2023, 12:37pm

Hi @utrautma
Not sure you need to remove the new_visit=1 after the page view. If I am not wrong (please tell me if I am), this is taken into account only for the page view.
Coming back to the callback itself, what is the exact behavior of your 1st code? (you can also put some console.log(...) in the callback )

utrautma · September 21, 2023, 8:34pm

Hi @heurteph-ei ,
the new_visit=1 approach is mentioned here https://matomo.org/faq/how-to/faq_187/ . The call is before the trackPageView-request, so I’m think its right.
The requirement for the callback is the following:
A logged in user was tracked with trackpageview. Now he logs out without a page-load and a new visit should be generated. An event should also be triggered that he has pressed a logout button.
I had assumed the callback function wouldn’t be executed until the trackPageview was processed. But apparently that is not guaranteed. This is because the code (trackEvent) within the callback function is sometimes executed before the trackPageView is completely processed.
As a result, the event is sometimes assigned to the visit before the logout.

heurteph-ei · September 22, 2023, 8:57am

Hi @utrautma
You’re right, I just tested, and the event with new_visit=1 indeed create also a new visit…
Browsing the Matomo GitHub, I found this:

github.com/matomo-org/matomo

Callback in sendRequest() / trackPageView() is not always executed

opened 11:41AM - 14 Oct 22 UTC

closed 04:12AM - 10 Nov 22 UTC

FalkHe

Bug not-in-changelog c: Tracking

## Expected Behavior The callback in a `trackPageView()` call (and others) shou…ld always be executed, once the tracking Request is sent. ```javascript window._paq.push(['trackPageView', null, null, function () { console.log('successfully tracked pageView'); }]); ``` ## Current Behavior In some circumstances, this is not happening. While testing, I noticed it's working in Firefox, but not in Chrome (v 106.0.5249.119 ). I tried to debug this issue and found [this line](https://github.com/matomo-org/matomo/blob/4.x-dev/js/piwik.js#L3099) to be different in execution. In FF `clientHintsResolved` is `true` and in Chrome it isn't. I went down the rabbit hole a bit deeper and found that `detectBrowserFeatures()` is called, `detectClientHints(callback)` is also called, but the given `callback` of the latter is not called in Chrome but is mandatory for `clientHintsResolved` to be `true`. A bit deeper, I found that `navigator.userAgentData.getHighEntropyValues()` behaves different in Firefox and Chrome. Nevertheless... What happens then, is that in `sendRequest(request, delay, callback)`, the `request` is put into a queue but - and that's the issue, IMO - `delay` and `callback` are ignored and lost at this moment. The Request in the Queue is executed (sent) later on, but my originally provided callback is not. :( ## Possible Solution 1. Respect the async behavior of getHighEntropyValues() and either wait for it or continue normally, even if the desired data isn't available in time 2. Put `delay` and `callback` along with `request` into the clientHintsRequestQueue and execute it from there. ## Steps to Reproduce 1. Setup a page with Matomo 2. test in Chrome (v 106.0.5249.119 ) 3. call trackPageView(null, null, function() { console.log('success'); }) 4. check if 'success' is logged ## Context I've some pages that perform an immediate redirect (via window.location) but need to be tracked via Matomo. Therefore I need to know when Matomo has finished the tracking call so I securely can leave the page. ( Maybe there is a better way? ) ## Your Environment Chrome (v 106.0.5249.119 ) Windows 11 Matomo version: 4.12.0

Will be fixed in Matomo 5.0

github.com/matomo-org/matomo

JS tracker calls callback too early

opened 09:38AM - 16 Jul 21 UTC

closed 08:13PM - 18 Jul 21 UTC

SassNinja

answered

## Expected Behavior I expect when I provide a callback to `trackEvent`, it…'s called AFTER the tracking is done meaning there's no pending request. ## Current Behavior When I pass a callback to `trackEvent` and immediately redirect the user once it's called, the request to matomo is still pending and therefore never finished. ![matomo_callback_issue](https://user-images.githubusercontent.com/19912475/125927181-f4e0584a-139d-47f7-9c90-58ab7864f24e.png) ## Possible Solution Not sure, where exactly the origin of that problem comes from. After digging into the code I haven't found anything suspicious though the result is definitely wrong. I assume it's related to this part in the code: https://github.com/matomo-org/matomo/blob/fa66bc580852c2b098ba5ea7f7ba57048f258714/js/piwik.js#L2800 ## Steps to Reproduce (for Bugs) 1. create a promise, track an event and pass the resolver as callback 2. wait until the promise is resolved (meaning the callback is called) and the redirect to another page 3. expect the matomo request being finished in the network panel in the browser dev tools ```javascript const trackEvent = () => { return new Promise(resolve => { window._paq.push(['trackEvent', 'category', 'action', undefined, undefined, undefined, resolve]) }) } const redirect = async () => { await trackEvent() console.log('expect matomo request being finished') window.location.href = 'https://...' } redirect() ``` ## Context I'm redirecting the used to another website once he's done with a renewal. Therefore I cannot track anything on the target page but must track it right before redirecting him. This means I need to know when the matomo request is done to be sure everything is tracked before the current page is left. ## Your Environment * Matomo Version: latest (4.3.1) * PHP Version: 7.4.20 * Server Operating System: * Additionally installed plugins: * Browser: Chrome * Operating System: Mac OS

you need then to disable the sendBeacon in this case

Could one of them explain your issue?

utrautma · September 22, 2023, 2:14pm

Hi @heurteph-ei , great that you picked out the two issues. Thank you very much.

Yes, both describe the problem I have.
I always get a callback so far, but sometimes too early. Here I will try to work without sendBeacon, although that could also have disadvantages. ongoing tracking requests cannot be processed securely when user is going to the next page.
The workaround of replying with a timer, as described in the first ticket, is also an approach. Waiting for Matomo 5 seems a bit too long at the moment.