Announcement: New features in the Attribution Reporting API

[Maud Nalpas]

Hi API testers,

New features for the Attribution Reporting API have landed in Chrome to address tester feedback. This is a bundle announcement for three distinct new features, that are described in more detail below:

1. Custom report windows, for faster reporting and selective reporting
2. Filter-based deduplication keys for aggregatable reports. [potentially breaking change] 
3. Verbose debug reports for source success registration.

Feature #1: Custom report windows

With custom report windows, you can instruct the browser to filter out conversions that occur after a certain time window. For event-level reports, custom report windows also allow you to get reports faster—for example, one day after click/view instead of two days.
Custom report windows are available starting from Chrome 110.

Documentation

See Handbook > Custom report windows.

What should you do? 

Review the documentation and consider leveraging custom report windows if they fulfil your use case.
Can you try it now?
Yes. Custom report windows are available in Chrome 110 (Stable at this time).

Feature #2: Filter-based deduplication keys for aggregatable reports (potentially breaking)

As previously announced, you can make your deduplication key for aggregatable reports vary based on your filter configuration. This unlocks use cases such as deduplicating aggregatable reports based on conversion type, or based on any other information that can be used in filters.

Filter-based deduplication keys are available starting from Chrome 112.
Documentation
See Handbook > Filter-based deduplication keys.
What should you do?
Were you using a deduplication key for aggregatable reports (aggregatable_deduplication_key), before Chrome 112?

• If you weren't: No action is needed — unless you want to use the new capabilities unlocked by this feature. Review Handbook > Filter-based deduplication keys for details. 
• If you were: This change is breaking. You need to migrate. Review the migration instructions in Handbook > Migrating deduplication keys. The migration steps should be minimal, please ask if you have any questions.

Can you try it now?
Yes. Filter-based deduplication keys are available in Chrome 112 (Canary/Dev at this time).

Feature #3: verbose debug reports for source success registration
Verbose debug reports help explain some Attribution Reporting loss you may be observing when testing the API. But they don't explain all of it, because they currently cover only some source registration failure scenarios. This is why starting from Chrome 112, we've added verbose debug reports for source success registration. These new reports give you insight into when a source registration is successful, to help you narrow down some other possible failure scenarios.
Documentation
See the debugging guides; we've updated these to include this new type of verbose debug report.
What should you do?

Do you already use debug reports—including verbose debug reports?

• If you don't: We recommend you start using debug reports, regardless of this change. Read more in the debugging guides.
• If you do: Expect to receive source registration success verbose debug reports starting from Chrome 112. No additional setup is required for you to receive these reports. Expect increased traffic on your verbose debug reports endpoint.

Can you try it now?

Yes. These new reports are available in Chrome 112 (today Canary and Dev).

To try it out:

• Open Chrome Canary (chrome://version should display 112 or 113). 
• Follow the demo setup instructions.
• In chrome://attribution-internals, open the Verbose Debug Reports tab.
• Open this page. Simply loading this page should successfully record a source event.
• In chrome://attribution-internals, in the Verbose Debug Reports tab, you should see a new row: a new verbose report was generated to signal a successful source registration.

Questions/Feedback

If you experience any issue, or have any implementation questions on these new features: please file an issue in our developer support repository.