feat: add modular services and repositories for improved code organization

Introduce repository pattern across multiple services, including `favorites`, `tags`, `sessions`, `reports`, `auth`, and more. Decouple crypto functionalities into modular services like `HashingService`, `JwtService`, and `EncryptionService`. Improve testability and maintainability by simplifying dependencies and consolidating utility logic.

backend/src/contents/contents.service.spec.ts

@@ -4,33 +4,28 @@ jest.mock("uuid", () => ({
 
 import { BadRequestException } from "@nestjs/common";
 import { ConfigService } from "@nestjs/config";
+import { CACHE_MANAGER } from "@nestjs/cache-manager";
 import { Test, TestingModule } from "@nestjs/testing";
 import { DatabaseService } from "../database/database.service";
 import { MediaService } from "../media/media.service";
 import { S3Service } from "../s3/s3.service";
 import { ContentsService } from "./contents.service";
+import { ContentsRepository } from "./repositories/contents.repository";
 
 describe("ContentsService", () => {
 	let service: ContentsService;
 	let s3Service: S3Service;
 	let mediaService: MediaService;
 
-	const mockDb = {
-		select: jest.fn().mockReturnThis(),
-		from: jest.fn().mockReturnThis(),
-		where: jest.fn().mockReturnThis(),
-		limit: jest.fn().mockReturnThis(),
-		offset: jest.fn().mockReturnThis(),
-		orderBy: jest.fn().mockReturnThis(),
-		innerJoin: jest.fn().mockReturnThis(),
-		insert: jest.fn().mockReturnThis(),
-		values: jest.fn().mockReturnThis(),
-		update: jest.fn().mockReturnThis(),
-		set: jest.fn().mockReturnThis(),
-		returning: jest.fn().mockResolvedValue([]),
-		onConflictDoNothing: jest.fn().mockReturnThis(),
-		transaction: jest.fn().mockImplementation((cb) => cb(mockDb)),
-		execute: jest.fn().mockResolvedValue([]),
+	const mockContentsRepository = {
+		findAll: jest.fn(),
+		count: jest.fn(),
+		create: jest.fn(),
+		incrementViews: jest.fn(),
+		incrementUsage: jest.fn(),
+		softDelete: jest.fn(),
+		findOne: jest.fn(),
+		findBySlug: jest.fn(),
 	};
 
 	const mockS3Service = {
@@ -48,46 +43,24 @@ describe("ContentsService", () => {
 		get: jest.fn(),
 	};
 
+	const mockCacheManager = {
+		store: {
+			keys: jest.fn().mockResolvedValue([]),
+		},
+		del: jest.fn(),
+	};
+
 	beforeEach(async () => {
 		jest.clearAllMocks();
 
-		const chain = {
-			select: jest.fn().mockReturnThis(),
-			from: jest.fn().mockReturnThis(),
-			where: jest.fn().mockReturnThis(),
-			orderBy: jest.fn().mockReturnThis(),
-			limit: jest.fn().mockReturnThis(),
-			offset: jest.fn().mockReturnThis(),
-			innerJoin: jest.fn().mockReturnThis(),
-			insert: jest.fn().mockReturnThis(),
-			values: jest.fn().mockReturnThis(),
-			update: jest.fn().mockReturnThis(),
-			set: jest.fn().mockReturnThis(),
-			returning: jest.fn().mockReturnThis(),
-			onConflictDoNothing: jest.fn().mockReturnThis(),
-		};
-
-		const mockImplementation = () => {
-			return Object.assign(Promise.resolve([]), chain);
-		};
-
-		for (const mock of Object.values(chain)) {
-
-			//TODO Fix : TS2774: This condition will always return true since this function is always defined. Did you mean to call it instead?
-			if (mock.mockReturnValue) {
-				mock.mockImplementation(mockImplementation);
-			}
-		}
-
-		Object.assign(mockDb, chain);
-
 		const module: TestingModule = await Test.createTestingModule({
 			providers: [
 				ContentsService,
-				{ provide: DatabaseService, useValue: { db: mockDb } },
+				{ provide: ContentsRepository, useValue: mockContentsRepository },
 				{ provide: S3Service, useValue: mockS3Service },
 				{ provide: MediaService, useValue: mockMediaService },
 				{ provide: ConfigService, useValue: mockConfigService },
+				{ provide: CACHE_MANAGER, useValue: mockCacheManager },
 			],
 		}).compile();
 
@@ -127,7 +100,8 @@ describe("ContentsService", () => {
 				mimeType: "image/webp",
 				size: 500,
 			});
-			mockDb.returning.mockResolvedValue([{ id: "content-id" }]);
+			mockContentsRepository.findBySlug.mockResolvedValue(null);
+			mockContentsRepository.create.mockResolvedValue({ id: "content-id" });
 
 			const result = await service.uploadAndProcess("user1", file, {
 				title: "Meme",
@@ -155,8 +129,8 @@ describe("ContentsService", () => {
 
 	describe("findAll", () => {
 		it("should return contents and total count", async () => {
-			mockDb.where.mockResolvedValueOnce([{ count: 10 }]); // for count
-			mockDb.offset.mockResolvedValueOnce([{ id: "1" }]); // for data
+			mockContentsRepository.count.mockResolvedValue(10);
+			mockContentsRepository.findAll.mockResolvedValue([{ id: "1" }]);
 
 			const result = await service.findAll({ limit: 10, offset: 0 });
 
@@ -167,9 +141,9 @@ describe("ContentsService", () => {
 
 	describe("incrementViews", () => {
 		it("should increment views", async () => {
-			mockDb.returning.mockResolvedValue([{ id: "1", views: 1 }]);
+			mockContentsRepository.incrementViews.mockResolvedValue([{ id: "1", views: 1 }]);
 			const result = await service.incrementViews("1");
-			expect(mockDb.update).toHaveBeenCalled();
+			expect(mockContentsRepository.incrementViews).toHaveBeenCalledWith("1");
 			expect(result[0].views).toBe(1);
 		});
 	});