Merge pull request #18018 from overleaf/revert-17906-ab-split-test-assignments-optim-pt2

Revert "[web] Store anonymous users split test assignments in new format in session"

GitOrigin-RevId: 2c1a95031a9d1d99b9dfef54eb4b80264a32ba0d

services/web/app/src/Features/SplitTests/SplitTestCache.js

@@ -12,7 +12,9 @@ class SplitTestCache extends CacheLoader {
   async load() {
     Metrics.inc('split_test_get_split_test_from_mongo', 1, {})
     const splitTests = await SplitTestManager.getRuntimeTests()
-    return new Map(splitTests.map(splitTest => [splitTest.name, splitTest]))
+    return new Map(
+      splitTests.map(splitTest => [splitTest.name, splitTest.toObject()])
+    )
   }
 
   serialize(value) {

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

@@ -492,10 +492,7 @@ function _getNonSaasAssignment(splitTestName) {
 
 async function _getSplitTest(name) {
   const splitTests = await SplitTestCache.get('')
-  const splitTest = splitTests?.get(name)
+  return splitTests?.get(name)
-  if (splitTest && !splitTest.archived) {
-    return splitTest
-  }
 }
 
 module.exports = {

services/web/app/src/Features/SplitTests/SplitTestManager.js

@@ -60,7 +60,9 @@ async function getSplitTests({ name, phase, type, active, archived }) {
 
 async function getRuntimeTests() {
   try {
-    return SplitTest.find({}).lean().exec()
+    return await SplitTest.find({
+      archived: { $ne: true },
+    }).exec()
   } catch (error) {
     throw OError.tag(error, 'Failed to get active split tests list')
   }

services/web/app/src/Features/SplitTests/SplitTestSessionHandler.js

@@ -9,35 +9,29 @@ const SplitTestUtils = require('./SplitTestUtils')
 const SplitTestUserGetter = require('./SplitTestUserGetter')
 
 const CACHE_TOMBSTONE_SPLIT_TEST_NOT_ACTIVE_FOR_USER = null
-const TOKEN_SEP = ';'
-// this is safe to use as a separator adjacent to a base64 string because Mongo object IDs
-// do not generate any padding when converted (24 hex digits = 12 bytes => multiple of 6),
-// thus do not contain any trailing `=`
-const KEY_VALUE_SEP = '='
-const ID_VERSION_SEP = '_'
-const VARIANT_DATE_SEP = ':'
 
 async function getAssignments(session) {
-  await _convertAnonymousAssignmentsIfNeeded(session)
+  if (!session.splitTests && !session.sta) {
-
-  if (!session.sta) {
     return undefined
   }
 
-  const assignments = {}
+  // await _convertAnonymousAssignmentsIfNeeded(session)
-  const tokens = session.sta.split(TOKEN_SEP)
+  const assignments = _.clone(session.splitTests || {})
+  if (session.sta) {
+    const tokens = session.sta.split(';')
     const splitTests = Array.from((await SplitTestCache.get('')).values())
     for (const token of tokens) {
       try {
         if (!token.length) {
           continue
         }
-      const [splitTestNameVersion, info] = token.split(KEY_VALUE_SEP)
+        const [splitTestNameVersion, info] = token.split('=')
-      const [splitTestId64, versionStr] =
+        const [splitTestId64, versionStr] = splitTestNameVersion.split('_')
-        splitTestNameVersion.split(ID_VERSION_SEP)
 
         const splitTest = splitTests.find(
-        test => splitTestId64 === _convertIdToBase64(test._id)
+          test =>
+            test._id.toString() ===
+            new ObjectId(Buffer.from(splitTestId64, 'base64')).toString()
         )
         if (!splitTest) {
           continue
@@ -45,7 +39,7 @@ async function getAssignments(session) {
 
         const splitTestName = splitTest.name
         const versionNumber = parseInt(versionStr)
-      const [variantChar, timestampStr36] = info.split(VARIANT_DATE_SEP)
+        const [variantChar, timestampStr36] = info.split(':')
         const assignedAt = new Date(parseInt(timestampStr36, 36) * 1000)
         let variantName
         if (variantChar === 'd') {
@@ -69,32 +63,46 @@ async function getAssignments(session) {
       } catch (error) {
         logger.error(
           { err: error, token },
-        'Failed to resolve cached anonymous split test assignments from session'
+          'Failed to resolve anonymous split test assignment from session'
         )
       }
     }
+  }
 
   return assignments
 }
 
 async function appendAssignment(session, assignment) {
-  await _convertAnonymousAssignmentsIfNeeded(session)
+  // await _convertAnonymousAssignmentsIfNeeded(session)
 
-  if (
+  if (!session.splitTests) {
-    !_hasExistingAssignment(
+    session.splitTests = {}
-      session,
-      assignment.splitTestId,
-      assignment.versionNumber
-    )
-  ) {
-    if (!session.sta) {
-      session.sta = ''
   }
-    const splitTests = await SplitTestCache.get('')
+  if (!session.splitTests[assignment.splitTestName]) {
-    const splitTest = splitTests.get(assignment.splitTestName)
+    session.splitTests[assignment.splitTestName] = []
-    const assignmentString = _buildAssignmentString(splitTest, assignment)
+  }
-    const separator = session.sta.length > 0 ? TOKEN_SEP : ''
+
-    session.sta += `${separator}${assignmentString}`
+  const assignments = await getAssignments(session)
+  if (
+    !_.find(assignments[assignment.splitTestName], {
+      variantName: assignment.variantName,
+      versionNumber: assignment.versionNumber,
+    })
+  ) {
+    // if (!session.sta) {
+    //   session.sta = ''
+    // }
+    // const splitTests = await SplitTestCache.get('')
+    // const splitTest = splitTests.get(assignment.splitTestName)
+    // const assignmentString = _buildAssignmentString(splitTest, assignment)
+    // const separator = session.sta.length > 0 ? ';' : ''
+    // session.sta += `${separator}${assignmentString}`
+    session.splitTests[assignment.splitTestName].push({
+      variantName: assignment.variantName,
+      versionNumber: assignment.versionNumber,
+      phase: assignment.phase,
+      assignedAt: assignment.assignedAt,
+    })
   }
 }
 
@@ -174,63 +182,62 @@ function collectSessionStats(session) {
       JSON.stringify(session.cachedSplitTestAssignments).length
     )
   }
-  if (session.sta) {
+  if (session.splitTests) {
     Metrics.summary(
       'split_test_session_storage_count',
-      (session.sta || '').split(';').length
+      (session.sta || '').split(';').length +
+        Object.keys(session.splitTests).length
     )
     Metrics.summary(
       'split_test_session_storage_size',
-      (session.sta || '').length
+      (session.sta || '').length + JSON.stringify(session.splitTests).length
     )
   }
 }
 
-async function _convertAnonymousAssignmentsIfNeeded(session) {
+// async function _convertAnonymousAssignmentsIfNeeded(session) {
-  if (session.splitTests) {
+//   if (typeof session.splitTests === 'object') {
-    const splitTests = await SplitTestCache.get('')
+//     const sessionAssignments = session.splitTests
-    if (!session.sta) {
+//     const splitTests = await SplitTestCache.get('')
-      session.sta = ''
+//     session.splitTests = ''
-    }
+//     for (const [splitTestName, assignments] of Object.entries(
-    for (const [splitTestName, assignments] of Object.entries(
+//       sessionAssignments
-      session.splitTests
+//     )) {
-    )) {
+//       const splitTest = splitTests.get(splitTestName)
-      const splitTest = splitTests.get(splitTestName)
+//       for (const assignment of assignments) {
-      for (const assignment of assignments) {
+//         const assignmentString = _buildAssignmentString(splitTest, assignment)
-        const assignmentString = _buildAssignmentString(splitTest, assignment)
+//         const separator = session.splitTests.length > 0 ? ';' : ''
-        const separator = session.sta.length > 0 ? TOKEN_SEP : ''
+//         session.splitTests += `${separator}${assignmentString}`
-        session.sta += `${separator}${assignmentString}`
+//       }
-      }
+//     }
-    }
+//   }
-    delete session.splitTests
+// }
-  }
-}
 
-function _hasExistingAssignment(session, splitTest, versionNumber) {
+// function _hasExistingAssignment(session, splitTest, versionNumber) {
-  if (!session.sta) {
+//   if (!session.sta) {
-    return false
+//     return false
-  }
+//   }
-  const index = session.sta.indexOf(
+//   const index = session.sta.indexOf(
-    `${_convertIdToBase64(splitTest._id)}${ID_VERSION_SEP}${versionNumber}=`
+//     `${_convertIdToBase64(splitTest._id)}_${versionNumber}=`
-  )
+//   )
-  return index >= 0
+//   return index >= 0
-}
+// }
 
-function _buildAssignmentString(splitTest, assignment) {
+// function _buildAssignmentString(splitTest, assignment) {
-  const { versionNumber, variantName, assignedAt } = assignment
+//   const { versionNumber, variantName, assignedAt } = assignment
-  const variants = SplitTestUtils.getCurrentVersion(splitTest).variants
+//   const variants = SplitTestUtils.getCurrentVersion(splitTest).variants
-  const splitTestId = _convertIdToBase64(splitTest._id)
+//   const splitTestId = _convertIdToBase64(splitTest._id)
-  const variantChar =
+//   const variantChar =
-    variantName === 'default'
+//     variantName === 'default'
-      ? 'd'
+//       ? 'd'
-      : _.findIndex(variants, { name: variantName })
+//       : _.findIndex(variants, { name: variantName })
-  const timestamp = Math.floor(assignedAt.getTime() / 1000).toString(36)
+//   const timestamp = Math.floor(assignedAt.getTime() / 1000).toString(36)
-  return `${splitTestId}${ID_VERSION_SEP}${versionNumber}${KEY_VALUE_SEP}${variantChar}${VARIANT_DATE_SEP}${timestamp}`
+//   return `${splitTestId}_${versionNumber}=${variantChar}:${timestamp}`
-}
+// }
 
-function _convertIdToBase64(id) {
+// function _convertIdToBase64(id) {
-  return new ObjectId(id).toString('base64')
+//   return new ObjectId(id).toString('base64')
-}
+// }
 
 module.exports = {
   getAssignments: callbackify(getAssignments),

services/web/test/unit/src/SplitTests/SplitTestSessionHandlerTests.js

@@ -15,45 +15,6 @@ describe('SplitTestSessionHandler', function () {
     }
     this.SplitTestUserGetter = {}
     this.Metrics = {}
-
-    this.SplitTestCache.get = sinon.stub().resolves(
-      new Map(
-        Object.entries({
-          'anon-test-1': {
-            _id: '661f92a4669764bb03f73e37',
-            name: 'anon-test-1',
-            versions: [
-              {
-                versionNumber: 1,
-                variants: [
-                  {
-                    name: 'enabled',
-                  },
-                ],
-              },
-            ],
-          },
-          'anon-test-2': {
-            _id: '661f92a9d68ea711d6bf2df4',
-            name: 'anon-test-2',
-            versions: [
-              {
-                versionNumber: 1,
-                variants: [
-                  {
-                    name: 'v-1',
-                  },
-                  {
-                    name: 'v-2',
-                  },
-                ],
-              },
-            ],
-          },
-        })
-      )
-    )
-
     this.SplitTestSessionHandler = SandboxedModule.require(MODULE_PATH, {
       requires: {
         './SplitTestCache': this.SplitTestCache,
@@ -191,6 +152,43 @@ describe('SplitTestSessionHandler', function () {
   })
 
   it('should merge assignments from both splitTests and sta fields', async function () {
+    this.SplitTestCache.get = sinon.stub().resolves(
+      new Map(
+        Object.entries({
+          'anon-test-1': {
+            _id: '661f92a4669764bb03f73e37',
+            name: 'anon-test-1',
+            versions: [
+              {
+                versionNumber: 1,
+                variants: [
+                  {
+                    name: 'enabled',
+                  },
+                ],
+              },
+            ],
+          },
+          'anon-test-2': {
+            _id: '661f92a9d68ea711d6bf2df4',
+            name: 'anon-test-2',
+            versions: [
+              {
+                versionNumber: 1,
+                variants: [
+                  {
+                    name: 'v-1',
+                  },
+                  {
+                    name: 'v-2',
+                  },
+                ],
+              },
+            ],
+          },
+        })
+      )
+    )
     const session = {
       splitTests: {
         'anon-test-1': [
@@ -225,18 +223,18 @@ describe('SplitTestSessionHandler', function () {
         },
       ],
       'anon-test-2': [
-        {
-          variantName: 'v-2',
-          versionNumber: 2,
-          phase: 'release',
-          assignedAt: new Date(1712858400000),
-        },
         {
           variantName: 'default',
           versionNumber: 1,
           phase: 'release',
           assignedAt: new Date(1712307600000),
         },
+        {
+          variantName: 'v-2',
+          versionNumber: 2,
+          phase: 'release',
+          assignedAt: new Date(1712858400000),
+        },
       ],
     })
   })