test: add comprehensive unit tests for core services

Added unit tests for the `api-keys`, `auth`, `categories`, `contents`, `favorites`, `media`, and `purge` services to improve test coverage and ensure core functionality integrity.

backend/src/media/media.service.spec.ts

@@ -0,0 +1,94 @@
+import * as fs from "node:fs/promises";
+import { BadRequestException, Logger } from "@nestjs/common";
+import { ConfigService } from "@nestjs/config";
+import { Test, TestingModule } from "@nestjs/testing";
+import ffmpeg from "fluent-ffmpeg";
+import sharp from "sharp";
+import { MediaService } from "./media.service";
+
+jest.mock("sharp");
+jest.mock("fluent-ffmpeg");
+jest.mock("node:fs/promises");
+jest.mock("uuid", () => ({ v4: () => "mock-uuid" }));
+
+describe("MediaService", () => {
+	let service: MediaService;
+
+	const mockSharp = {
+		metadata: jest.fn().mockResolvedValue({ width: 100, height: 100 }),
+		webp: jest.fn().mockReturnThis(),
+		toBuffer: jest.fn().mockResolvedValue(Buffer.from("processed")),
+	};
+
+	beforeEach(async () => {
+		jest.clearAllMocks();
+		jest.spyOn(Logger.prototype, "error").mockImplementation(() => {});
+		jest.spyOn(Logger.prototype, "warn").mockImplementation(() => {});
+		(sharp as unknown as jest.Mock).mockReturnValue(mockSharp);
+
+		const module: TestingModule = await Test.createTestingModule({
+			providers: [
+				MediaService,
+				{
+					provide: ConfigService,
+					useValue: {
+						get: jest.fn((key) => {
+							if (key === "CLAMAV_HOST") return "localhost";
+							if (key === "CLAMAV_PORT") return 3310;
+						}),
+					},
+				},
+			],
+		}).compile();
+
+		service = module.get<MediaService>(MediaService);
+	});
+
+	it("should be defined", () => {
+		expect(service).toBeDefined();
+	});
+
+	describe("processImage", () => {
+		it("should process an image to webp", async () => {
+			const result = await service.processImage(Buffer.from("input"), "webp");
+			expect(result.extension).toBe("webp");
+			expect(result.buffer).toEqual(Buffer.from("processed"));
+			expect(mockSharp.webp).toHaveBeenCalled();
+		});
+
+		it("should throw BadRequestException on error", async () => {
+			mockSharp.toBuffer.mockRejectedValue(new Error("Sharp error"));
+			await expect(service.processImage(Buffer.from("input"))).rejects.toThrow(
+				BadRequestException,
+			);
+		});
+	});
+
+	describe("processVideo", () => {
+		it("should process a video", async () => {
+			const mockFfmpegCommand = {
+				toFormat: jest.fn().mockReturnThis(),
+				videoCodec: jest.fn().mockReturnThis(),
+				audioCodec: jest.fn().mockReturnThis(),
+				outputOptions: jest.fn().mockReturnThis(),
+				on: jest.fn().mockImplementation(function (event, cb) {
+					if (event === "end") setTimeout(cb, 0);
+					return this;
+				}),
+				save: jest.fn().mockReturnThis(),
+			};
+			(ffmpeg as unknown as jest.Mock).mockReturnValue(mockFfmpegCommand);
+			(fs.readFile as jest.Mock).mockResolvedValue(Buffer.from("processed-video"));
+			(fs.writeFile as jest.Mock).mockResolvedValue(undefined);
+			(fs.unlink as jest.Mock).mockResolvedValue(undefined);
+
+			const result = await service.processVideo(
+				Buffer.from("video-input"),
+				"webm",
+			);
+
+			expect(result.extension).toBe("webm");
+			expect(result.buffer).toEqual(Buffer.from("processed-video"));
+		});
+	});
+});