Bug 1777182 - Add a sendBeacon uploader

[Dexterp37]

Before merging this PR:

• Remove the changes to the sample app
• Figure out with @scholtzan why these submissions are not going through

The use of that API has some implications to the rest of the ecosystem (ingestion, tooling) so we likely want to have this optionally enabled for a while. Unfortunately, there's no way to simple test this without using it on a product. So here's what I'd recommend:

1. Review and merge this (not used anywhere!)
2. Cut a new prerelease version
3. Use the new prerelease in the debug view or the glean dictionary, and add URL parameters to conditionally turn this on
4. Validate if this works in the pipeline without changing anything ?

Pull Request checklist

• Quality: Make sure this PR builds and runs cleanly.
  • Inside the glean/ folder, run:
    • npm run test Runs all tests
    • npm run lint Runs all linters
• Tests: This PR includes thorough tests or an explanation of why it does not
• Changelog: This PR includes a changelog entry to CHANGELOG.md or an explanation of why it does not need one
• Documentation: This PR includes documentation changes, an explanation of why it does not need that or a follow-up bug has been filed to do that work
  • Documentation should be added to The Glean Book when making changes to Glean's user facing API
    • When changes to the Glean Book are necessary, link to the corresponding PR on the mozilla/glean repository
  • Documentation should be added to the Glean.js developer documentation when making internal code changes

[Dexterp37]

@badboy @rosahbruno do you have thoughts on the testing plan?

[badboy]

testing in production!
Yeah, we don't rely on glean dictionary data for anything, so testing it there gets us the most real-world testing.

[scholtzan]

Instead of having sendBeacon send an escaped JSON string, it actually shouldn't get escaped. This is working:

navigator.sendBeacon("https://incoming.telemetry.mozilla.org/submit/debug-ping-view/events/1/e2588a68-6801-45c0-86a8-03f6784b0168", '{"events":[{"category":"sample","name":"random_event","timestamp":0}],"ping_info":{"seq":4,"start_time":"2023-11-29T18:50+01:00","end_time":"2023-11-29T19:05+01:00","reason":"max_capacity"},"client_info":{"telemetry_sdk_build":"4.0.0-pre.0","client_id":"cae639c1-7462-49e6-a8a7-7eced5656820","first_run_date":"2023-11-27+01:00","os":"Windows","os_version":"Unknown","architecture":"Unknown","locale":"it-IT","app_build":"Unknown","app_display_version":"Unknown"}}');

[rosahbruno]

Everything looks good. The testing plan also makes sense, we talked about this offline too.

The only call outs I have here are

1. Just making sure that we plan on using the supported uploader later once we verify that sendbeacon is working.
2. The ignore-await stuff in sendbeacon_uploader feels like maybe we could do it differently, but I am going to take a look and get back to you tomorrow.

[Dexterp37]

All right, I believe this is finally ready for review folks! I'm able to see the live data using this local hack and with a query like:

select * FROM `moz-fx-data-shared-prod.debug_ping_view_live.events_v1` AS e where date(submission_timestamp) >= "2023-11-30" order by submission_timestamp desc

I'm also able to see stuff in the debug view when setting the debug view tags, since this falls back to fetch in that case.

[rosahbruno]

I think everything here looks good! Excited to get this landed and start testing

[rosahbruno]

I think this should just be a boolean without the need for a ternary, but not a big deal.