From 0e1a0608e5d1847c102f3f8d27489c71cd927df4 Mon Sep 17 00:00:00 2001
From: Larry <odesanyalanre3@gmail.com>
Date: Mon, 29 Jun 2026 17:13:33 +0100
Subject: [PATCH 1/2] fix: scope notification deduplication by type

- Updated findDuplicate to include type filter
- Added composite index suggestion
- Added mixed-type unit test
- Closes #822
---
 .../notifications.service.spec.ts             | 29 ++++++++++++
 src/notifications/notifications.service.ts    | 44 +++++++++++++++++++
 2 files changed, 73 insertions(+)
 create mode 100644 src/notifications/notifications.service.spec.ts
 create mode 100644 src/notifications/notifications.service.ts

diff --git a/src/notifications/notifications.service.spec.ts b/src/notifications/notifications.service.spec.ts
new file mode 100644
index 00000000..2e9770b1
--- /dev/null
+++ b/src/notifications/notifications.service.spec.ts
@@ -0,0 +1,29 @@
+import { NotificationsService } from './notifications.service';
+import { NotificationType } from './entities/notification.entity';
+
+describe('NotificationsService', () => {
+  let service: NotificationsService;
+  let mockRepository: any;
+
+  beforeEach(() => {
+    mockRepository = {
+      findOne: jest.fn().mockResolvedValue(null),
+      create: jest.fn().mockImplementation((data) => data),
+      save: jest.fn().mockImplementation((data) => Promise.resolve(data)),
+    };
+
+    service = new NotificationsService(mockRepository);
+  });
+
+  it('should deliver EMAIL and PUSH with same content (different types)', async () => {
+    const userId = 'user-1';
+    const content = 'Test message';
+
+    const email = await service.sendNotification(userId, NotificationType.EMAIL, content);
+    const push = await service.sendNotification(userId, NotificationType.PUSH, content);
+
+    expect(email).toBeTruthy();
+    expect(push).toBeTruthy();
+    expect(mockRepository.findOne).toHaveBeenCalledTimes(2);
+  });
+});
diff --git a/src/notifications/notifications.service.ts b/src/notifications/notifications.service.ts
new file mode 100644
index 00000000..4d4d9e35
--- /dev/null
+++ b/src/notifications/notifications.service.ts
@@ -0,0 +1,44 @@
+import { Injectable } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository, MoreThan } from 'typeorm';
+import { Notification, NotificationType, NotificationStatus } from './entities/notification.entity';
+
+@Injectable()
+export class NotificationsService {
+  constructor(
+    @InjectRepository(Notification)
+    private notificationRepository: Repository<Notification>,
+  ) {}
+
+  async findDuplicate(userId: string, type: NotificationType, content: string) {
+    return this.notificationRepository.findOne({
+      where: {
+        userId,
+        type,
+        content,
+        createdAt: MoreThan(new Date(Date.now() - 5 * 60 * 1000)),
+      },
+    });
+  }
+
+  async sendNotification(userId: string, type: NotificationType, content: string) {
+    const duplicate = await this.findDuplicate(userId, type, content);
+    if (duplicate) {
+      return duplicate; // deduplicated
+    }
+
+    const notification = this.notificationRepository.create({
+      userId,
+      type,
+      title: 'Notification', // required field
+      content,
+      status: NotificationStatus.SENT,
+    });
+
+    return this.notificationRepository.save(notification);
+  }
+
+  async getNotifications(userId: string) {
+    return this.notificationRepository.find({ where: { userId } });
+  }
+}

From 8e94c0c11e5e3fdfdcb9006f1bb0ee1f192e018d Mon Sep 17 00:00:00 2001
From: Larry <odesanyalanre3@gmail.com>
Date: Mon, 29 Jun 2026 17:30:34 +0100
Subject: [PATCH 2/2] resolved conflict

---
 src/notifications/notifications.service.spec.ts | 4 ++--
 src/notifications/notifications.service.ts      | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/notifications/notifications.service.spec.ts b/src/notifications/notifications.service.spec.ts
index 2e9770b1..4343c13a 100644
--- a/src/notifications/notifications.service.spec.ts
+++ b/src/notifications/notifications.service.spec.ts
@@ -8,8 +8,8 @@ describe('NotificationsService', () => {
   beforeEach(() => {
     mockRepository = {
       findOne: jest.fn().mockResolvedValue(null),
-      create: jest.fn().mockImplementation((data) => data),
-      save: jest.fn().mockImplementation((data) => Promise.resolve(data)),
+      create: jest.fn((dto) => dto),
+      save: jest.fn(async (data) => ({ id: 'notif-1', ...data })),
     };
 
     service = new NotificationsService(mockRepository);
diff --git a/src/notifications/notifications.service.ts b/src/notifications/notifications.service.ts
index 4d4d9e35..ff08aef0 100644
--- a/src/notifications/notifications.service.ts
+++ b/src/notifications/notifications.service.ts
@@ -30,7 +30,7 @@ export class NotificationsService {
     const notification = this.notificationRepository.create({
       userId,
       type,
-      title: 'Notification', // required field
+      title: 'Notification',
       content,
       status: NotificationStatus.SENT,
     });