feat(backend): initial setup for cms backend service

backend/src/services/media.service.ts

@@ -0,0 +1,87 @@
+import sharp from 'sharp';
+import { writeFile, mkdir } from 'fs/promises';
+import path from 'path';
+import crypto from 'crypto';
+import { env } from '../config/env.js';
+
+export class MediaService {
+  private allowedMimeTypes = ['image/jpeg', 'image/png', 'image/webp'];
+  private maxFileSize: number;
+
+  constructor() {
+    this.maxFileSize = env.MAX_FILE_SIZE;
+  }
+
+  /**
+   * Validate file type and size
+   */
+  async validateFile(file: any): Promise<void> {
+    if (!this.allowedMimeTypes.includes(file.mimetype)) {
+      throw new Error(`Invalid file type. Allowed types: ${this.allowedMimeTypes.join(', ')}`);
+    }
+
+    // Check file size
+    const buffer = await file.toBuffer();
+    if (buffer.length > this.maxFileSize) {
+      throw new Error(`File too large. Maximum size: ${this.maxFileSize / 1024 / 1024}MB`);
+    }
+  }
+
+  /**
+   * Generate safe filename
+   */
+  generateFilename(originalName: string): string {
+    const ext = path.extname(originalName);
+    const hash = crypto.randomBytes(8).toString('hex');
+    const timestamp = Date.now();
+    return `${timestamp}-${hash}${ext}`;
+  }
+
+  /**
+   * Optimize and save image
+   */
+  async processAndSaveImage(
+    file: any,
+    destinationDir: string
+  ): Promise<{ filename: string; url: string }> {
+    await this.validateFile(file);
+
+    // Ensure destination directory exists
+    await mkdir(destinationDir, { recursive: true });
+
+    // Generate filename
+    const filename = this.generateFilename(file.filename);
+    const filepath = path.join(destinationDir, filename);
+
+    // Get file buffer
+    const buffer = await file.toBuffer();
+
+    // Process image with sharp (optimize and resize if needed)
+    await sharp(buffer)
+      .resize(2000, 2000, {
+        fit: 'inside',
+        withoutEnlargement: true,
+      })
+      .jpeg({ quality: 85 })
+      .png({ quality: 85 })
+      .webp({ quality: 85 })
+      .toFile(filepath);
+
+    // Return filename and URL path
+    return {
+      filename,
+      url: `/images/${filename}`,
+    };
+  }
+
+  /**
+   * Save image to git workspace
+   */
+  async saveToGitWorkspace(
+    file: any,
+    workspaceDir: string
+  ): Promise<{ filename: string; url: string }> {
+    const imagesDir = path.join(workspaceDir, 'public', 'images');
+    return this.processAndSaveImage(file, imagesDir);
+  }
+}