[web] cleanup archived split-test assignments from user record on login (#33365)

* [web] cleanup archived split-test assignments from user record on login

Co-authored-by: Anna Claire Fields <anna.fields@overleaf.com>

* [migrations] purge archived split tests from all users

Co-authored-by: Anna Claire Fields <anna.fields@overleaf.com>

* [web] add missing mock and update snapshot test

* [web] gracefully access db.users.splitTests

---------

Co-authored-by: Anna Claire Fields <anna.fields@overleaf.com>
GitOrigin-RevId: bd185074a402556d7b7c812208cf834dd52b27a5

services/web/app/src/Features/Authentication/AuthenticationController.mjs

@@ -25,6 +25,7 @@ import Modules from '../../infrastructure/Modules.mjs'
 import { expressify, promisify } from '@overleaf/promise-utils'
 import { handleAuthenticateErrors } from './AuthenticationErrors.mjs'
 import EmailHelper from '../Helpers/EmailHelper.mjs'
+import SplitTestHandler from '../SplitTests/SplitTestHandler.mjs'
 
 const { hasAdminAccess } = AdminAuthorizationHelper
 
@@ -647,6 +648,10 @@ function _loginAsyncHandlers(req, user, anonymousAnalyticsId, isNewUser) {
   UserHandler.promises.populateTeamInvites(user).catch(err => {
     logger.warn({ err }, 'error setting up login data')
   })
+  SplitTestHandler.promises.userMaintenanceOnLogin(user).catch(err => {
+    const userId = user._id
+    logger.warn({ err, userId }, 'error cleaning up split-tests on login')
+  })
   LoginRateLimiter.recordSuccessfulLogin(user.email, () => {})
   AuthenticationController._recordSuccessfulLogin(user._id, () => {})
   AuthenticationController.ipMatchCheck(req, user)

services/web/app/src/Features/SplitTests/SplitTestHandler.mjs

@@ -978,6 +978,21 @@ async function decrementLabsVariantCounter(splitTestName) {
   }
 }
 
+async function userMaintenanceOnLogin(user) {
+  const splitTests = (await SplitTestCache.get('')).values()
+  const toCleanup = {}
+  for (const splitTest of splitTests) {
+    if (splitTest.archived && user.splitTests?.[splitTest.name]) {
+      toCleanup[`splitTests.${splitTest.name}`] = 1
+    }
+  }
+  if (Object.keys(toCleanup).length > 0) {
+    await UserUpdater.promises.updateUser(user._id, {
+      $unset: toCleanup,
+    })
+  }
+}
+
 export default {
   getPercentile,
   getAssignment: callbackify(getAssignment),
@@ -997,5 +1012,6 @@ export default {
     hasUserBeenAssignedToVariant,
     decrementLabsVariantCounter,
     incrementLabsVariantCounterIfBelowLimit,
+    userMaintenanceOnLogin,
   },
 }