@loopback/example-file-transfer

An example application to demonstrate file uploads and downloads for LoopBack 4

Summary

This application exposes POST /files endpoint that accepts
multipart/form-data based file uploads. The uploaded files can be listed using
GET /files and individual files can be downloaded using
GET /files/.

Key artifacts

- FileUploadController
- Expose POST /files endpoint to allow file uploads

- FileUploadService - an Express middleware from multer
- A service provider that returns a configured multer request handler

The file upload is configured with multer options in
src/application.ts as follows:

``ts
// Configure file upload with multer options
const multerOptions: multer.Options = {
storage: multer.diskStorage({
// Upload files to .sandbox
destination: path.join(__dirname, '../.sandbox'),
// Use the original file name as is
filename: (req, file, cb) => {
cb(null, file.originalname);
},
}),
};
this.configure(FILE_UPLOAD_SERVICE).to(multerOptions);
`

- FileDownloadController
- Expose GET /files endpoint to list uploaded files
- Expose GET /files/{filename} endpoint to download a file

Use

Start the app:

`sh
npm start
`

The application will start on port 3000. Open http://localhost:3000 in your
browser. You can try to upload a few files using the web UI or API explorer.

!upload-download

By default, the uploaded files will be stored in .sandbox folder under the
application root directory. The directory can be configured via
fileStorageDirectory of application config.

Contributions

- Guidelines
- Join the team

Tests

Run npm test` from the root folder.

Contributors

See
all contributors.

License

MIT