Configurable attribution windows

[jinghao]

Hi @johnwilander and @hober !

I noticed that the current spec hard codes a 7 day retention for the ad click, leading to up to a 7-day attribution window to conversions.

Advertising products typically support multiple different conversion windows, with the most common ones being 1 day, 7 days and 28 or 30 days. Some advertisers (i.e. those that sell cheap widgets) may care more about short-consideration window conversions while others (i.e. those that sell furniture) may care more about long-consideration window conversions, and they indicate that by specifying their attribution window when configuring their ads.

As such, it would be really helpful to allow these fields to be configurable. I understand for privacy reasons we should limit the expressiveness and range of the fields, and I'm open to different options. Requiring it to be in days resolution would help a lot. If necessary, they can be restricted to one of those options listed above (though I can't speak to whether there are other common attribution windows not represented there).

What do you think?

[jinghao]

Hi, just checking back in to hear your thoughts. This is a pretty important need given our obligations to provide accurate measurement to our advertisers. Thank you!