Did we already decide how AMC corresponds to Mobile Beta? (I.e. does AMC always imply - or exclude - Mobile Beta?) In that case it might be worth considering to add a new value to the existing mf-m key instead of adding a new key. @phuedx, thoughts ?

Do note that this task focusses on making the change in our application code, which is made possible by restricting AMC to logged-in users (who are always served by the application servers). It may be prudent to home all of our X-Analytics-related logic in the Varnish VCL's themselves.

Looks clear to me. It's ready to work on.

Edit

This is currently blocked on a privacy review.

@Tbayer: Should we contact Legal for this?

@ovasileva has sent the request. We're waiting for a response.

For the record, to track progress: We received followup questions from Legal on January 24, and replied on the same day. (Last week was taken up by the WMF All Hands meeting.)

Update: still waiting on a reply from Legal. Sent them a note to check in on the status Feb 11.

The task has now been reviewed for privacy by the Legal team. No concerns were raised. Moving to to-do.

Change 492924 had a related patch set uploaded (by Niedzielski; owner: Stephen Niedzielski):
[mediawiki/extensions/MobileFrontend@master] WIP: Analytics: add AMC tag to X-Analytics header

https://gerrit.wikimedia.org/r/492924

I believe this is ready for review. ^Extra thanks to those who contributed to technical details on this task. It was useful!

The X-Analitycs header when AMC and Beta modes are on:
X-Analytics: mf-m=b%2Camc;ns=-1;special=MobileOptions;loggedIn=1

Note: We urlencode the ,character.

/cc @Tbayer

Change 492924 merged by jenkins-bot:
[mediawiki/extensions/MobileFrontend@master] Analytics: add AMC tag to X-Analytics header

https://gerrit.wikimedia.org/r/492924

We still need to check at some point that this is correctly processed on Varnish and stored in the webrequest table (where we need it to conduct the analysis). But that will have to wait until the change is in production, because the domain en.m.wikipedia.beta.wmflabs.org is not captured in webrequest. Probably best to create a separate task for that, and close this one?

For later reference, here is a query for checking, which should yield amc values:

SELECT DISTINCT x_analytics_map['mf-m'] AS values FROM wmf.webrequest WHERE year = 2019 AND month = 3 AND day = 12 AND hour = 0;

OK
values
NULL
b
Time taken: 26.1 seconds, Fetched: 2 row(s)

Test Result:Production

Status: ✅ PASS
OS: macOS Mojave
Browser: Chrome DevTools Device Emulator (iPhone X)

Test Artifact(s):

• AMC on / beta on
  
• AMC off / beta on
  
• AMC on / beta off
  
• AMC off / beta off