feat : implement pagination to get-all-waitlist

src/modules/waitlist/tests/waitlist.service.spec.ts

@@ -15,6 +15,7 @@ describe('WaitlistService', () => {
 
   const mockWaitlistRepository = {
     find: jest.fn(),
+    findAndCount: jest.fn(),
     save: jest.fn(),
     create: jest.fn(),
     findOne: jest.fn(),
@@ -48,10 +49,67 @@ describe('WaitlistService', () => {
   });
 
   describe('getAllWaitlist', () => {
-    it('should return all waitlist', async () => {
-      await waitlistService.getAllWaitlist();
+    it('should return paginated waitlist results with default values when no parameters are provided', async () => {
+      // Arrange: setup default values (page = 1, limit = 10)
+      const mockWaitlistEntries = [
+        { id: '1', full_name: 'Alice', email: '[email protected]' },
+        { id: '2', full_name: 'Bob', email: '[email protected]' },
+      ];
+      const totalCount = 2;
+      mockWaitlistRepository.findAndCount = jest.fn().mockResolvedValue([mockWaitlistEntries, totalCount]);
 
-      expect(waitlistRepository.find).toHaveBeenCalled();
+      // Act: call service without pagination parameters
+      const result = await waitlistService.getAllWaitlist();
+
+      // Assert: defaults (skip: 0, take: 10) should be used
+      expect(mockWaitlistRepository.findAndCount).toHaveBeenCalledWith({
+        skip: 0,
+        take: 10,
+      });
+      expect(result).toEqual({
+        status: 'Success',
+        status_code: 200,
+        data: {
+          current_page: 1,
+          total_pages: 1, // since totalCount is 2 and default limit is 10
+          total_waitlist_count: totalCount,
+          waitlist: mockWaitlistEntries,
+        },
+        message: 'Waitlist found successfully',
+      });
+    });
+
+    it('should return paginated waitlist results with provided page and limit', async () => {
+      // Arrange: setup custom pagination values
+      const mockWaitlistEntries = [
+        { id: '3', full_name: 'Charlie', email: '[email protected]' },
+        { id: '4', full_name: 'David', email: '[email protected]' },
+      ];
+      const totalCount = 20;
+      mockWaitlistRepository.findAndCount = jest.fn().mockResolvedValue([mockWaitlistEntries, totalCount]);
+
+      const page = 2;
+      const limit = 5;
+
+      // Act: call service with page and limit parameters
+      const result = await waitlistService.getAllWaitlist(page, limit);
+
+      // Assert: ensure proper skip and take values
+      expect(mockWaitlistRepository.findAndCount).toHaveBeenCalledWith({
+        skip: (page - 1) * limit, // (2-1)*5 = 5
+        take: limit, // 5
+      });
+      expect(result).toEqual({
+        status: 'Success',
+        status_code: 200,
+        data: {
+          current_page: page, // e.g., 2
+          total_pages: Math.ceil(totalCount / limit), // e.g., 4 if totalCount is 20 and limit is 5
+          total_waitlist_count: totalCount,
+          waitlist: mockWaitlistEntries,
+        },
+        message: 'Waitlist found successfully',
+      });
     });
   });
 

src/modules/waitlist/waitlist.service.ts

@@ -7,6 +7,7 @@ import { CreateWaitlistDto } from './dto/create-waitlist.dto';
 import { WaitlistResponseDto } from './dto/create-waitlist-response.dto';
 import * as SYS_MSG from '@shared/constants/SystemMessages';
 import { CustomHttpException } from '@shared/helpers/custom-http-filter';
+import { STATUS_CODES } from 'http';
 
 @Injectable()
 export default class WaitlistService {
@@ -34,8 +35,25 @@ export default class WaitlistService {
     return { message: 'You are all signed up!' };
   }
 
-  async getAllWaitlist() {
-    const waitlist = await this.waitlistRepository.find();
-    return { message: 'Waitlist found successfully', data: { waitlist } };
+  async getAllWaitlist(page: number = 1, limit: number = 10) {
+    if (page < 1) page = 1;
+    if (limit < 1) limit = 10;
+
+    const [waitlist, total] = await this.waitlistRepository.findAndCount({
+      skip: (page - 1) * limit,
+      take: limit,
+    });
+
+    return {
+      status: 'Success',
+      status_code: 200,
+      message: 'Waitlist found successfully',
+      data: {
+        waitlist,
+        total_waitlist_count: total,
+        current_page: page,
+        total_pages: Math.ceil(total / limit),
+      },
+    };
   }
 }