Calls from daily update url

[fhoering]

The first OT implemented this mechanism of dailyUpdate URL:
https://github.com/WICG/turtledove/blob/main/Proposed_First_FLEDGE_OT_Details.md#interest-group-updating

The FOT#1 will also include a mechanism to update interest groups that have just had the chance to participate in an auction initiated by navigator.runAdAuction(). The updating will happen shortly after the auction and will update interest groups that haven’t been updated in the last 24 hours. This updating will be done using the interest group’s dailyUpdateUrl setting as the explainer discusses.

The FOT#1 will not include a periodic background interest group update mechanism.

On our side we added a dailyUpdateUrl to update the eligible ads for each interest group (IG) and it is actually called in very few cases only.

In general when we see the user for tagging we create the IG and add all eligible creatives from currently running campaigns. Paused campaigns are not added yet to the IG. So when there are no activate campaigns we will create the IG but the ads field of the IG will be empty.

In the meantime campaigns might get restarted again or new campaigns might have been created.

When we get a bid opportunity for this empty IG the computeBid function is not executed and it seems like the IG update function is not called either (because the ads field is empty). In any case, even if the update would have been called here, as it is executed after the computeBid function it is already too late as we might not get a next opportunity for this user with a updated IG.

It should be noted that one workaround would be to put all eligible campaigns (active and paused) in the IG and then filter out the campaigns in the trusted server call. But this seems not like a very efficient solution as many IG would be created just to be filtered out later and would put load on the device for no reason. It doesn’t fix the issue for newly created campaigns also.

Updating the IG every 24h within a real background thread would fix this problem. The description above let’s us think that this is planned at one point. Any update on this ?

[JensenPaul]

it seems like the IG update function is not called either (because the ads field is empty)

Hmm, I thought Chrome did fetch IG updates even when the ads field is empty. I believe we designed it this way to handle the restarted campaign use case you're describing. If you're witnessing a different behavior, feel free to file a bug in the Chromium bug tracker at https://crbug.com/new

[fhoering]

As discussed in the meeting on 2023-02-01 we checked on our side if we see the expected behavior. The update call respects the 24h rule and it is executed on IG with empty ads. So works as expected.

On full bid request traffic it seems good enough to update after each bid request instead of a daily update thread which is aligned with comment #361 (comment).

So I'll close the ticket.