File Upload

Handling file uploads in DolphJS is extremely straightforward because the framework ships with its own robust, internal file uploading utility useFileUploader provided by @dolphjs/packages. You don’t need to manually install multer or any external dependencies!

Creating the Middleware

You can configure useFileUploader with storage destinations, file filters, and extension restrictions. DolphJS provides both diskStorage and memoryStorage helpers to manage where your files go.

import { useFileUploader, diskStorage } from '@dolphjs/dolph/packages';
import path from 'path';

// Configure storage
const storage = diskStorage({
  destination: (req, file, cb) => {
    // Save files to the 'uploads' directory
    cb(null, './uploads');
  },
  filename: (req, file, cb) => {
    // Prevent naming collisions
    const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1e9);
    cb(null, file.fieldname + '-' + uniqueSuffix + path.extname(file.originalname));
  },
});

export const uploadMedia = useFileUploader({
  storage,
  fieldname: 'document',
  type: 'single', // can also be 'array' or 'fields'
  limit: 5 * 1024 * 1024, // 5MB limit
  extensions: ['.png', '.jpg', '.jpeg', '.pdf'] // automatically filters files!
});

Applying to Controllers

Use the @UseMiddleware decorator to apply the newly created uploadMedia middleware to your route. When the request reaches your handler, the file data will be securely populated in req.file (or req.files if uploading an array).

import { DolphControllerHandler } from '@dolphjs/dolph/classes';
import { Dolph } from '@dolphjs/dolph/common';
import { Route, Post, DReq, DRes, UseMiddleware } from '@dolphjs/dolph/decorators';
import { SuccessResponse, ErrorResponse, DRequest, DResponse } from '@dolphjs/dolph/common';
import { uploadMedia } from '../utils/uploader.config';

@Route('files')
export class UploadController extends DolphControllerHandler<Dolph> {

  @Post('single')
  @UseMiddleware(uploadMedia)
  async uploadSingleFile(@DReq() req: DRequest, @DRes() res: DResponse) {
    if (!req.file) {
      return ErrorResponse({ res, body: 'No file uploaded or invalid format', status: 400 });
    }

    // Pass file data to a service, or return the path
    SuccessResponse({
      res,
      body: {
        message: 'File uploaded successfully',
        filePath: req.file.path,
      },
    });
  }
}