Edge case: page view and ecommerce conversion tracked in the same second create wrong visitEcommerceStatus

[mattab]

After staring at the code for two hours, then getting good debug data, I figured the bug: if a page view is tracked at the same second as an ecommerce order, this pageview request may erase the visitEcommerceStatus flag.

Explanation:

1. the ecommerce order request is received
2. at same time the pageview for the checkout page is tracked.
   This page view "reads" first the visit (which does not yet have "visitEcommerceStatus == ordered")
   1b) the ecommerce is recorded and "visitEcommerceStatus == ordered" is set
   2b) the pageview is recorded and "visitEcommerceStatus == none"

[mattab]

In 5809c35: Refs #4909 Only update the visitEcommerceStatus flag if it's not NONE.
This will prevent some occurrences of this bug, but not the case where visitEcommerceStatus == abandonedCart

[mattab]

There are two solutions to this bug:

• On the checkout page, when tracking the order with trackEcommerceOrder(...), do not on the same page call trackPageView().
• The proper fix would be to process the JS requests as bulk: I created ticket: Javascript tracker can send tracking API requests as bulk for better performance #4910

[mattab]

In 25bfb48: Refs #4909 Only update the visitEcommerceStatus flag if it's different from current value.

[mattab]

After that last commit I think this should fix the issue. So #4910 is not necessary.

[mattab]

see also #5966

[mattab]

See also: #9916 It is not possible to record more than one conversion per second for the same visit