Uploading Files to an API with Node.js and FormData

const axios = require('axios');
const FormData = require('form-data');
const fs = require('fs');
const path = require('path');

async function uploadFileToAPI(apiEndpoint, filePath, fileName, additionalFields = {}) {
  try {
    const form = new FormData();

    // Append the file stream
    const fileStream = fs.createReadStream(filePath);
    form.append('file', fileStream, { filename: fileName }); // 'file' is the field name on the API side

    // Append additional fields
    for (const key in additionalFields) {
      form.append(key, additionalFields[key]);
    }

    const response = await axios.post(apiEndpoint, form, {
      headers: {
        ...form.getHeaders(),
        // Add any other necessary headers, e.g., Authorization
        // 'Authorization': 'Bearer YOUR_ACCESS_TOKEN'
      },
      maxBodyLength: Infinity, // Important for large files
      maxContentLength: Infinity, // Important for large files
    });

    console.log('File upload successful:', response.data);
    return response.data;
  } catch (error) {
    console.error('File upload failed:', error.response ? error.response.data : error.message);
    throw error;
  }
}

// Example Usage:
// const fileToUpload = path.join(__dirname, 'my-document.pdf');
// const apiEndpoint = 'https://api.example.com/upload';
// uploadFileToAPI(fileToUpload, 'document.pdf', apiEndpoint, { description: 'Important document' })
//   .then(data => console.log('API response:', data))
//   .catch(err => console.error('Upload error:', err));