From de99fe668745f93b9f25839b780c76bbce4b1154 Mon Sep 17 00:00:00 2001
From: Georgy Berezhnoy <gohabereg@gmail.com>
Date: Sun, 5 Dec 2021 04:01:46 +0300
Subject: [PATCH 1/2] Save affected users info to daily events

---
 lib/utils.js                 |  4 ++++
 workers/grouper/src/index.ts | 13 +++++++++----
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index 418aa43f..b8609683 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -50,6 +50,10 @@ function deepDiff(source, target) {
 function arrayDiff(source, target) {
   const diffArray = [];
 
+  if (!Array.isArray(source)) {
+    return target;
+  }
+
   for (let i = 0; i < target.length; i++) {
     diffArray[i] = deepDiff(source[i], target[i]);
   }
diff --git a/workers/grouper/src/index.ts b/workers/grouper/src/index.ts
index e39370e1..a879ca5a 100644
--- a/workers/grouper/src/index.ts
+++ b/workers/grouper/src/index.ts
@@ -164,10 +164,12 @@ export default class GrouperWorker extends Worker {
       repetitionId = await this.saveRepetition(task.projectId, newRepetition);
     }
 
+    const eventUser = task.event.user;
+
     /**
      * Store events counter by days
      */
-    await this.saveDailyEvents(task.projectId, uniqueEventHash, task.event.timestamp, repetitionId);
+    await this.saveDailyEvents(task.projectId, uniqueEventHash, task.event.timestamp, repetitionId, eventUser?.id);
 
     /**
      * Add task for NotifierWorker
@@ -205,13 +207,13 @@ export default class GrouperWorker extends Worker {
    */
   private async findSimilarEvent(projectId: string, event: EventDataAccepted<EventAddons>): Promise<GroupedEventDBScheme | undefined> {
     const eventsCountToCompare = 60;
-    const diffTreshold = 0.35;
+    const diffThreshold = 0.35;
 
     const lastUniqueEvents = await this.findLastEvents(projectId, eventsCountToCompare);
 
     return lastUniqueEvents.filter(prevEvent => {
       const distance = levenshtein(event.title, prevEvent.payload.title);
-      const threshold = event.title.length * diffTreshold;
+      const threshold = event.title.length * diffThreshold;
 
       return distance < threshold;
     }).pop();
@@ -384,13 +386,15 @@ export default class GrouperWorker extends Worker {
    * @param {string} eventHash - event hash
    * @param {string} eventTimestamp - timestamp of the last event
    * @param {string|null} repetitionId - event's last repetition id
+   * @param {string} userId - affected user id
    * @returns {Promise<void>}
    */
   private async saveDailyEvents(
     projectId: string,
     eventHash: string,
     eventTimestamp: number,
-    repetitionId: string | null
+    repetitionId: string | null,
+    userId = 'anonymous'
   ): Promise<void> {
     if (!projectId || !mongodb.ObjectID.isValid(projectId)) {
       throw new ValidationError('GrouperWorker.saveDailyEvents: Project ID is invalid or missed');
@@ -423,6 +427,7 @@ export default class GrouperWorker extends Worker {
               lastRepetitionId: repetitionId,
             },
             $inc: { count: 1 },
+            $addToSet: { affectedUsers: userId },
           },
           { upsert: true });
     } catch (err) {

From 33d059ebd8bb0afbc74031ab55c8c96017430780 Mon Sep 17 00:00:00 2001
From: Georgy Berezhnoy <gohabereg@gmail.com>
Date: Sun, 26 Dec 2021 01:11:57 +0300
Subject: [PATCH 2/2] Add tests for affected users set

---
 workers/grouper/tests/index.test.ts | 32 +++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/workers/grouper/tests/index.test.ts b/workers/grouper/tests/index.test.ts
index 36203a35..00d24360 100644
--- a/workers/grouper/tests/index.test.ts
+++ b/workers/grouper/tests/index.test.ts
@@ -19,10 +19,12 @@ jest.mock('../../../lib/cache/controller', () => {
     }
 
     // eslint-disable-next-line @typescript-eslint/no-empty-function, jsdoc/require-jsdoc
-    public flushAll(): void {}
+    public flushAll(): void {
+    }
 
     // eslint-disable-next-line @typescript-eslint/no-empty-function, jsdoc/require-jsdoc
-    public set(): void {}
+    public set(): void {
+    }
   };
 });
 
@@ -214,6 +216,32 @@ describe('GrouperWorker', () => {
 
       expect((await dailyEventsCollection.findOne({})).lastRepetitionId).toEqual(repetition._id);
     });
+
+    test('Should update affected users list', async () => {
+      const task1 = generateTask();
+      const task2 = generateTask();
+
+      await worker.handle(task1);
+      await worker.handle(task2);
+
+      expect((await dailyEventsCollection.findOne({})).affectedUsers).toEqual([task1.event.user.id, task2.event.user.id]);
+    });
+
+    test('Should add anonymous user to affected users list if user is not passed with event', async () => {
+      await worker.handle(generateTask({ user: undefined }));
+
+      expect((await dailyEventsCollection.findOne({})).affectedUsers).toEqual([ 'anonymous' ]);
+    });
+
+    test('Should not add user to affected users list if its already there', async () => {
+      const task1 = generateTask();
+      const task2 = generateTask({ user: { id: task1.event.user.id } });
+
+      await worker.handle(task1);
+      await worker.handle(task2);
+
+      expect((await dailyEventsCollection.findOne({})).affectedUsers).toEqual([ task1.event.user.id ]);
+    });
   });
 
   describe('Saving repetitions', () => {