File Uploads & Downloads in JavaScript

// File upload
const formData = new FormData();
formData.append('file', fileInput.files[0]);
formData.append('name', 'Document');

const response = await axios.post('/api/upload', formData, {
  headers: {
    'Content-Type': 'multipart/form-data'
  },
  onUploadProgress: (progressEvent) => {
    const percent = Math.round(
      (progressEvent.loaded * 100) / progressEvent.total
    );
    console.log(\`Upload: \${percent}%\`);
  }
});