Does traffic source persist?
As part of improving conversion rate, I need to track where our users come from, what they did on the site, and whether they have made purchase. One use case is for look at all purchase events, where did the customers come from.
For the initial interactions on the site, we track the referral urls or UTM params if provided (this tracking is done on the client side). However, the purchase event is tracked from the server side (without all the referral details). The user has the same userID for actions they performed before they've made a purchase and after. If the purchase event itself doesn't have UTM params attached, will it not associate to the right referral source if user's pre-purchase activities all have UTM params?
An example of metrics illustrated in Mixpanel: here
If I use Google Analytics to see all the campaign sources, will this particular instance of CustomItineraryDestinationSubscription event not have campaign being 'dev_test'?
Re: Does traffic source persist?
Well there are a few details missing here but I'll give it a shot.
First, if the shopping experience flows across the same domain and the GA code is present on every page, the attribution should be intact. If the checkout happens elsewhere and you can add code, you'll need cross domain tracking on both sites. If you can't add code then you'll want to have the shopper returned to a thank you page on your site.
Regarding the parameters:
Once the user lands with UTM params, the document.referrer is ignored and the utm params are used for attribution and tied to the _ga value on the server side for Universal Analytics or set in _utmz for classic analytics. Once that is done the params are useless and do not need to be maintained page to page. This is also normal server behavior.