Aggregate Attribution Reporting API and FLEDGE

[jonasz]

Hi,

The Attribution Reporting API repo has recently been updated with some details regarding aggregate reports.

While the linked document focuses on a specific use case of producing reports in a cross-domain setting (vide "attribution source context" and "trigger context"), the mechanism itself could also be used in FLEDGE for:

1. reporting impression-level data
   • technically: producing histogram_contributions from within generate_bid and triggering them in cases of a won bid
2. reporting click-level data
   • analogous to 1., but this would be a separate histogram_contributions object, triggered after a click
3. reporting conversion-level data
   • being able to dynamically produce the attributionsourcecontext parameter from within generate_bid
4. (optionally?) reporting lost-impression-level data
   • similar to 1. and 2., but triggered after a lost bid

This would address issue #93 (training of bidding models); and also potentially #164, #172.

I was wondering, is it indeed the intention to incorporate aggregate reports specification into FLEDGE?

If so, could FLEDGE work with insecure-single-server as an interim step? Or do we still need to look for another interim solution, like custom_reporting_token described in #93?

Best regards, Jonasz

[jonasz]

@csharrison Hi Charlie, just a friendly FYI, as this issue may be interesting to you. Any feedback you may have would be valued.

For everyone interested, I'm also planning to raise this issue at the FLEDGE call tomorrow (26 May 2021).