[web] Cleanup plans-2026-phase-1 - phase 4: rest of backend (#34771)

* Remove `plans-2026-phase-1` from subscription module

* Remove code related to `plans-2026-phase-1`

* Remove `SplitTestUserGetter.getProjection`

* Update tests

* Remove last mentions of `plans-2026-phase-1`

* In test, wait for `_updateCustomerIoSubscriptionProperties` to be done

* Remove `purchaseAddon` test

* Remove AI-addon tests

* Fix `_quotaTierToAllowance` throwing on zero-grant tiers

`!quota` treated `0` as invalid, so `basic` (grant 0) threw. Check `typeof quota !== 'number'` alone. Unmasked once branch removed the split-test branch that skipped this path.

* Extract `waitForCustomerIoSync` helper in FeaturesUpdater tests

* https://github.com/overleaf/internal/pull/34771#discussion_r3552882875

GitOrigin-RevId: 0fe0e41b7a4105a3c4739214e2fffb77e91dbc42

services/web/app/src/Features/Project/ProjectController.mjs

@@ -492,7 +492,6 @@ const _ProjectController = {
       'wf-enable-freemium-super-complete',
       'wf-enable-super-complete-promotion',
       'wf-rebrand',
-      'plans-2026-phase-1',
       'testing-ai-usage',
       'wf-fake-non-english-suggestions',
       'editor-tabs',

services/web/app/src/Features/Project/ProjectListController.mjs

@@ -539,7 +539,7 @@ async function projectListPage(req, res, next) {
   const aiBlocked =
     Features.hasFeature('saas') && !(await _canUseAIAssist(user))
   const hasAiAssist =
-    Features.hasFeature('saas') && (await _userHasAIAssist(req, res, user))
+    Features.hasFeature('saas') && (await _userHasAIAssist(user))
 
   const splitTests = [
     // Split tests that will be made available to the frontend
@@ -949,24 +949,11 @@ function _hasActiveFilter(filters) {
 }
 
 /**
- * @param {any} req
- * @param {any} res
  * @param {any} user
  */
-// todo: quota clean-up: rename function and vars
-async function _userHasAIAssist(req, res, user) {
-  let hasPremiumAiFeatures
-  const inQuotaSplitTest = await SplitTestHandler.promises.featureFlagEnabled(
-    req,
-    res,
-    'plans-2026-phase-1'
-  )
-  if (inQuotaSplitTest) {
-    hasPremiumAiFeatures =
-      user.features?.aiUsageQuota === Settings.aiFeatures.unlimitedQuota
-  } else {
-    hasPremiumAiFeatures = user.features?.aiErrorAssistant === true
-  }
+async function _userHasAIAssist(user) {
+  const hasPremiumAiFeatures =
+    user.features?.aiUsageQuota === Settings.aiFeatures.unlimitedQuota
   // Check if the user has a non free trial version of our AI features
   if (hasPremiumAiFeatures) {
     return true

services/web/app/src/Features/Subscription/FeaturesUpdater.mjs

@@ -20,8 +20,6 @@ import CustomerIoPlanHelpers from './CustomerIoPlanHelpers.mjs'
 import { GroupPolicy } from '../../models/GroupPolicy.mjs'
 import { AI_ADD_ON_CODE } from './AiHelper.mjs'
 import { fetchNothing } from '@overleaf/fetch-utils'
-import SplitTestHandler from '../SplitTests/SplitTestHandler.mjs'
-import SplitTestUserGetter from '../SplitTests/SplitTestUserGetter.mjs'
 
 /**
  * Enqueue a job for refreshing features for the given user
@@ -48,8 +46,8 @@ async function refreshFeatures(userId, reason) {
     _id: 1,
     features: 1,
     email: 1,
-    // analyticsId + labsProgram (analytics) and the split test fields below
-    ...SplitTestUserGetter.getProjection('plans-2026-phase-1'),
+    analyticsId: 1,
+    labsProgram: 1,
   })
   const oldFeatures = _.clone(user.features)
   const features = await computeFeatures(userId)
@@ -94,19 +92,8 @@ async function refreshFeatures(userId, reason) {
   //  skip if they are the reason we are refreshing features (they'd already be up to date)
   if (featuresChanged && reason !== 'writefullEntitlementSynced') {
     try {
-      // todo: quota clean-up: simplify once split test isnt needed
-      let hasPremiumAiFeatures
-      const inQuotaSplitTest =
-        await SplitTestHandler.promises.featureFlagEnabledForMongoUser(
-          user,
-          'plans-2026-phase-1'
-        )
-      if (inQuotaSplitTest) {
-        hasPremiumAiFeatures =
-          newFeatures.aiUsageQuota === Settings.aiFeatures.unlimitedQuota
-      } else {
-        hasPremiumAiFeatures = Boolean(newFeatures.aiErrorAssistant)
-      }
+      const hasPremiumAiFeatures =
+        newFeatures.aiUsageQuota === Settings.aiFeatures.unlimitedQuota
       // update WF with the current feature set for the user
       await fetchNothing(
         `${Settings.writefull.overleafApiUrl}/api/user/status/update-overleaf-status`,

services/web/app/src/Features/Subscription/SubscriptionController.mjs

@@ -22,27 +22,15 @@ import AuthorizationManager from '../Authorization/AuthorizationManager.mjs'
 import Modules from '../../infrastructure/Modules.mjs'
 import async from 'async'
 import HttpErrorHandler from '../Errors/HttpErrorHandler.mjs'
-import {
-  AI_ADD_ON_CODE,
-  subscriptionChangeIsAiAssistUpgrade,
-} from './AiHelper.mjs'
+import { AI_ADD_ON_CODE } from './AiHelper.mjs'
 import PlansLocator from './PlansLocator.mjs'
 import { User } from '../../models/User.mjs'
 import UserGetter from '../User/UserGetter.mjs'
-import PermissionsManager from '../Authorization/PermissionsManager.mjs'
 import { sanitizeSessionUserForFrontEnd } from '../../infrastructure/FrontEndUser.mjs'
 import { z, parseReq } from '../../infrastructure/Validation.mjs'
-import SubscriptionLocator from './SubscriptionLocator.mjs'
 import { PaymentProviderSubscriptionChange } from './PaymentProviderEntities.mjs'
 
-const {
-  DuplicateAddOnError,
-  AddOnNotPresentError,
-  PaymentActionRequiredError,
-  PaymentFailedError,
-  MissingBillingInfoError,
-  MultiplePendingChangesError,
-} = Errors
+const { AddOnNotPresentError, MultiplePendingChangesError } = Errors
 
 const SUBSCRIPTION_PAUSED_REDIRECT_PATH =
   '/user/subscription?redirect-reason=subscription-paused'
@@ -102,23 +90,6 @@ async function _checkRecurlySubscriptionPauseStatus(subscription) {
   )
 }
 
-/** Check if a user's subscription is manual or custom
- * @param {Record<string, any>} user - The user object
- * @returns {Promise<boolean>}
- */
-async function _isManualOrCustomSubscription(user) {
-  const subscription = await SubscriptionLocator.promises.getUsersSubscription(
-    user._id
-  )
-  if (!subscription) {
-    return false
-  }
-
-  return (
-    subscription.customAccount || subscription.collectionMethod === 'manual'
-  )
-}
-
 /**
  * Check if a user's subscription is currently paused
  * @param {Record<string, any>} user - The user object
@@ -190,7 +161,6 @@ async function userSubscriptionPage(req, res) {
     res,
     'combined-user-management'
   )
-  await SplitTestHandler.promises.getAssignment(req, res, 'plans-2026-phase-1')
   const groupPricingDiscount = await SplitTestHandler.promises.getAssignment(
     req,
     res,
@@ -531,241 +501,24 @@ function cancelV1Subscription(req, res, next) {
  * @param {any} res
  */
 async function previewAddonPurchase(req, res) {
-  const user = SessionManager.getSessionUser(req.session)
-  const userId = user._id
   const addOnCode = req.params.addOnCode
-  const purchaseReferrer = req.query.purchaseReferrer
-  const redirectedPaymentErrorCode = req.query.errorCode
 
   if (addOnCode !== AI_ADD_ON_CODE) {
     return HttpErrorHandler.notFound(req, res, `Unknown add-on: ${addOnCode}`)
   }
 
-  const { variant: plans2026Phase1Variant } =
-    await SplitTestHandler.promises.getAssignment(
-      req,
-      res,
-      'plans-2026-phase-1'
-    )
-  if (plans2026Phase1Variant === 'enabled') {
-    return res.redirect(
-      '/user/subscription?redirect-reason=ai-assist-unavailable'
-    )
-  }
-
-  const canUseAi = await PermissionsManager.promises.checkUserPermissions(
-    user,
-    ['use-ai']
+  return res.redirect(
+    '/user/subscription?redirect-reason=ai-assist-unavailable'
   )
-  if (!canUseAi) {
-    return res.redirect(
-      '/user/subscription?redirect-reason=ai-assist-unavailable'
-    )
-  }
-
-  const isManualOrCustom = await _isManualOrCustomSubscription(user)
-  if (isManualOrCustom) {
-    return res.redirect(
-      '/user/subscription?redirect-reason=ai-assist-unavailable'
-    )
-  }
-
-  const { isPaused, redirectPath } = await checkSubscriptionPauseStatus(user)
-  if (isPaused) {
-    return res.redirect(redirectPath)
-  }
-
-  let paymentMethod
-  try {
-    /** @type {PaymentMethod[]} */
-    paymentMethod = await Modules.promises.hooks.fire(
-      'getPaymentMethod',
-      userId
-    )
-  } catch (err) {
-    if (err instanceof MissingBillingInfoError) {
-      // We will get MissingBillingInfoError if a manual subscription doesn't have billing info
-      // but doesn't marked as manual on the Overleaf side
-      logger.error(
-        { err },
-        'User has no billing info, cannot preview add-on purchase'
-      )
-      return res.redirect(
-        '/user/subscription?redirect-reason=ai-assist-unavailable'
-      )
-    }
-    if (
-      err instanceof Error &&
-      err.constructor.name === 'PaymentServiceResourceNotFoundError'
-    ) {
-      return res.redirect(
-        '/user/subscription?redirect-reason=ai-assist-unavailable'
-      )
-    }
-    throw err
-  }
-
-  let subscriptionChange
-  try {
-    subscriptionChange =
-      await SubscriptionHandler.promises.previewAddonPurchase(userId, addOnCode)
-
-    const { isPremium: hasAiAssistViaWritefull } =
-      await UserGetter.promises.getWritefullData(userId)
-    const isAiUpgrade = subscriptionChangeIsAiAssistUpgrade(subscriptionChange)
-    if (hasAiAssistViaWritefull && isAiUpgrade) {
-      return res.redirect(
-        '/user/subscription?redirect-reason=writefull-entitled'
-      )
-    }
-  } catch (err) {
-    if (err instanceof DuplicateAddOnError) {
-      return res.redirect('/user/subscription?redirect-reason=double-buy')
-    }
-    if (
-      err instanceof Error &&
-      err.constructor.name === 'PaymentServiceResourceNotFoundError'
-    ) {
-      return res.redirect(
-        '/user/subscription?redirect-reason=ai-assist-unavailable'
-      )
-    }
-    throw err
-  }
-
-  const addOn = PlansLocator.findLocalPlanInSettings(addOnCode)
-  if (!addOn) {
-    return HttpErrorHandler.notFound(req, res, `Unknown add-on: ${addOnCode}`)
-  }
-
-  /** @type {SubscriptionChangePreview} */
-  const changePreview = makeChangePreview(
-    {
-      type: 'add-on-purchase',
-      addOn: {
-        code: addOn.planCode,
-        name: addOn.name,
-      },
-    },
-    subscriptionChange,
-    paymentMethod[0]
-  )
-
-  res.render('subscriptions/preview-change', {
-    changePreview,
-    purchaseReferrer,
-    redirectedPaymentErrorCode,
-  })
 }
 
-const purchaseAddonSchema = z.object({
-  params: z.object({
-    addOnCode: z.string(),
-  }),
-})
-
 /**
  * @param {any} req
  * @param {any} res
  * @param {any} next
  */
 async function purchaseAddon(req, res, next) {
-  const user = SessionManager.getSessionUser(req.session)
-  const { params } = parseReq(req, purchaseAddonSchema)
-  const addOnCode = params.addOnCode
-  // currently we only support having a quantity of 1
-  const quantity = 1
-  // currently we only support one add-on, the Ai add-on
-  if (addOnCode !== AI_ADD_ON_CODE) {
-    return res.sendStatus(404)
-  }
-
-  const { variant: plans2026Phase1Variant } =
-    await SplitTestHandler.promises.getAssignment(
-      req,
-      res,
-      'plans-2026-phase-1'
-    )
-  if (plans2026Phase1Variant === 'enabled') {
-    return res.sendStatus(404)
-  }
-
-  const { isPaused } = await checkSubscriptionPauseStatus(user)
-  if (isPaused) {
-    return HttpErrorHandler.badRequest(
-      req,
-      res,
-      'Cannot purchase add-ons while subscription is paused.'
-    )
-  }
-
-  logger.debug({ userId: user._id, addOnCode }, 'purchasing add-ons')
-  try {
-    await SubscriptionHandler.promises.purchaseAddon(
-      user._id,
-      addOnCode,
-      quantity
-    )
-  } catch (err) {
-    if (err instanceof DuplicateAddOnError) {
-      HttpErrorHandler.badRequest(
-        req,
-        res,
-        'Your subscription already includes this add-on',
-        { addon: addOnCode }
-      )
-    } else if (err instanceof PaymentActionRequiredError) {
-      logger.debug(
-        { userId: user._id },
-        'Customer needs to perform payment action to complete transaction'
-      )
-      return res.status(402).json({
-        message: 'Payment action required',
-        clientSecret: /** @type {any} */ (err).info.clientSecret,
-        publicKey: /** @type {any} */ (err).info.publicKey,
-      })
-    } else if (err instanceof PaymentFailedError) {
-      logger.debug(
-        {
-          userId: user._id,
-          reason: /** @type {any} */ (err).info.reason,
-          adviceCode: /** @type {any} */ (err).info.adviceCode,
-        },
-        'Payment failed for transaction'
-      )
-      return res.status(402).json({
-        message: 'Payment failed',
-        reason: /** @type {any} */ (err).info.reason,
-        adviceCode: /** @type {any} */ (err).info.adviceCode,
-      })
-    } else if (err instanceof MultiplePendingChangesError) {
-      logger.warn(
-        { userId: user._id, err, addOnCode },
-        'Cannot purchase add-on: multiple pending changes'
-      )
-      return res.status(422).json({
-        code: 'multiple_pending_changes',
-        message:
-          'Cannot complete purchase while there are multiple pending subscription changes. Please contact support.',
-      })
-    } else {
-      if (err instanceof Error) {
-        OError.tag(err, 'something went wrong purchasing add-ons', {
-          user_id: user._id,
-          addOnCode,
-        })
-      }
-      return next(err)
-    }
-  }
-
-  try {
-    await FeaturesUpdater.promises.refreshFeatures(user._id, 'add-on-purchase')
-  } catch (err) {
-    logger.error({ err }, 'Failed to refresh features after add-on purchase')
-  }
-
-  return res.sendStatus(200)
+  return res.sendStatus(404)
 }
 
 const removeAddonSchema = z.object({

services/web/app/src/infrastructure/rate-limiters/AiFeatureUsageRateLimiter.mjs

@@ -3,8 +3,6 @@
 import UserGetter from '../../Features/User/UserGetter.mjs'
 import FeatureUsageRateLimiter from './FeatureUsageRateLimiter.mjs'
 import Settings from '@overleaf/settings'
-import SplitTestHandler from '../../Features/SplitTests/SplitTestHandler.mjs'
-import SplitTestUserGetter from '../../Features/SplitTests/SplitTestUserGetter.mjs'
 import FeaturesHelper from '../../Features/Subscription/FeaturesHelper.mjs'
 
 class AiFeatureUsageRateLimiter extends FeatureUsageRateLimiter {
@@ -20,31 +18,16 @@ class AiFeatureUsageRateLimiter extends FeatureUsageRateLimiter {
     const user = await UserGetter.promises.getUser(userId, {
       features: 1,
       writefull: 1,
-      ...SplitTestUserGetter.getProjection('plans-2026-phase-1'),
     })
-    // todo: quota clean-up: remove aiErrorAssistant checking, and split test
-    const inQuotaSplitTest =
-      await SplitTestHandler.promises.featureFlagEnabledForMongoUser(
-        user,
-        'plans-2026-phase-1'
-      )
 
-    if (inQuotaSplitTest) {
-      const wfQuota = user.writefull?.isPremium
-        ? Settings.writefull.quotaTierGranted
-        : Settings.aiFeatures.freeQuota
-      const mergedFeatures = FeaturesHelper.mergeFeatures(user.features, {
-        aiUsageQuota: wfQuota,
-      })
-      const quotaTier = mergedFeatures.aiUsageQuota
-      return _quotaTierToAllowance(quotaTier)
-    } else {
-      const DEFAULT_ALLOWANCE = 1
-      const ADD_ON_ALLOWANCE = 200
-      const hasAddOn =
-        user?.features?.aiErrorAssistant || user?.writefull?.isPremium
-      return hasAddOn ? ADD_ON_ALLOWANCE : DEFAULT_ALLOWANCE
-    }
+    const wfQuota = user?.writefull?.isPremium
+      ? Settings.writefull.quotaTierGranted
+      : Settings.aiFeatures.freeQuota
+    const mergedFeatures = FeaturesHelper.mergeFeatures(user?.features, {
+      aiUsageQuota: wfQuota,
+    })
+    const quotaTier = mergedFeatures.aiUsageQuota
+    return _quotaTierToAllowance(quotaTier)
   }
 }
 
@@ -57,7 +40,7 @@ class AiFeatureUsageRateLimiter extends FeatureUsageRateLimiter {
  */
 function _quotaTierToAllowance(quotaTier) {
   const quota = Settings.quotaGrants.ai[quotaTier]
-  if (!quota || typeof quota !== 'number') {
+  if (typeof quota !== 'number') {
     throw new Error(`Quota tier "${quotaTier}" is not initialized in settings`)
   }
   return Math.floor(quota)

services/web/app/src/infrastructure/rate-limiters/WorkbenchRateLimiter.mjs

@@ -1,6 +1,5 @@
 // @ts-check
 import SplitTestHandler from '../../Features/SplitTests/SplitTestHandler.mjs'
-import SplitTestUserGetter from '../../Features/SplitTests/SplitTestUserGetter.mjs'
 import UserGetter from '../../Features/User/UserGetter.mjs'
 import TokenUsageRateLimiter from './TokenUsageRateLimiter.mjs'
 /** @typedef {{usage?: number | null, periodStart?: Date | null}} FeatureUsage */
@@ -28,29 +27,15 @@ class WorkbenchRateLimiter extends TokenUsageRateLimiter {
       return 0
     }
     const user = await UserGetter.promises.getUser(userId, {
-      features: 1,
-      writefull: 1,
-      ...SplitTestUserGetter.getProjection('plans-2026-phase-1'),
+      alphaProgram: 1,
     })
 
     if (user?.alphaProgram) {
       return ALPHA_USER_TOKEN_ALLOWANCE
     }
 
-    // todo: quota clean-up: remove split test
-    let hasAddOn
-    const inQuotaSplitTest =
-      await SplitTestHandler.promises.featureFlagEnabledForMongoUser(
-        user,
-        'plans-2026-phase-1'
-      )
-    if (inQuotaSplitTest) {
-      // post rollout, all users have the same token limit (fair usage)
-      return DEFAULT_USER_TOKEN_ALLOWANCE
-    } else {
-      hasAddOn = user.features.aiErrorAssistant || user.writefull?.isPremium
-      return hasAddOn ? DEFAULT_USER_TOKEN_ALLOWANCE : 0
-    }
+    // all users have the same token limit (fair usage)
+    return DEFAULT_USER_TOKEN_ALLOWANCE
   }
 }
 export default new WorkbenchRateLimiter()