Auxia control group

[tomrf1]

The new requirement:

1. keep a fixed 5% of the global audience excluded from Auxia (though they can still see gates)
2. track participation of this 5% in the pageview table, regardless of whether they see gates

The proposed solution:

• On every page view, put 5% of the audience into a special NoAuxiaSignInGate AB test. This means the page tracks membership of the "test" through ophan. There are no variants in this test, it's just a way to track these browsers.
• The API call for the sign-in gate includes a flag indicating that the browser is in the NoAuxiaSignInGate test, and it excludes them from Auxia based on this.
• This would enable us to query the pageview table for browsers in theNoAuxiaSignInGate 5% group using the existing ab_test_array field.

Note - this is separate from the existing logic in SDC that splits the audience between Auxia and the hardcoded gate logic. It's necessary to do this control group client-side so that we can track it in the pageview data.

Implementation

1. Sends a new boolean flag, isInAuxiaControlGroup, to the SDC endpoint for sign-in gates
2. Assigns the last 5% of mvt values to a new NoAuxiaSignInGate AB test. This isn't a real AB test, and it only has a 'control' variant. It's a way to select a fixed 5% of browsers for the auxia control group.
3. Refactors the canShowSignInGatePortal function to make the parameters clearer. It has a lot of parameters, so it now takes an interface CanShowSignInGateProps, which makes calling it cleaner and safer.

There will need to be a change in SDC to exclude users from Auxia if this flag is set.

Testing

Tested locally by changing the mvt cookie and observing the request to SDC.

With an mvt value in the bottom 95% of the range, the flag is set to false:

With an mvt value in the top 5% of the range, the flag is set to true:

The abTestRegister event that we send to ophan includes the new NoAuxiaSignInGate "test":

Note - the existing SignInGateMainControl test here is meaningless and needs to be removed!

[github-actions]

Deploy build 46400 of Mobile::mobile-apps-rendering to CODE

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• Deploy build 46400 of Mobile::mobile-apps-rendering to CODE
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From guardian/actions-riff-raff.

[github-actions]

Deploy build 22148 of dotcom:rendering-all to CODE

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• Deploy build 22148 of dotcom:rendering-all to CODE
• Deploy parts of build 22148 to CODE by previewing it first
• What's on CODE right now?

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From guardian/actions-riff-raff.

[github-actions]

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[shtukas]

Nice solution to the problem, and hopefully at some point, we will not need to set the mvt value anymore 🙂

[gu-prout]

Seen on PROD (merged by @tomrf1 7 minutes and 55 seconds ago) Please check your changes!