post base64 binary data with nodejs request module

postBinaryData.js

const convert = require('buffer-to-stream');
const request = require('request');

/**
 * Post binary data in base64.
 * @param opt The request options
 * @param data The binary data in base64 string
 * @param cb The request callback
 */
function _postBinaryData(opt, data, cb) {
  const buf = Buffer.from(data, 'base64');
  const readable = convert(buf);

  opt.headers = opt.headers || {};
  opt.headers['Content-Length'] = Buffer.byteLength(buf);

  let chunk = '';
  let res = null;
  let err = null;

  let stream = request
    .post(opt)
    .on('response', function (response) {
      res = response;
    })
    .on('data', function (buffer) {
      chunk += buffer.toString();
    })
    .on('end', function () {
      cb(err, res, chunk);
    })
    .on('error', function (error) {
      err = error;
    });

  readable.pipe(stream);
}

// Promisify postBinaryData
function postBinaryData(opt, data) {
  return new Promise((resolve, reject) => {
    _postBinaryData(opt, data, (err, res, body) => {
      if (err) {
        reject(err);
      } else {
        resolve(body);
      }
    });
  }
}

Sample Usage

const contentUrl = 'data:application/pdf;base64,JVBERi0xLjQNC..';

const data = contentUrl.split(';base64,').pop();

const opt = {
  uri: 'https://example.com/v1/media',
  headers: {
       'Content-Type': 'application/pdf'
    }
};

postBinaryData(opt, data).then(body => {
    console.log(JSON.parse(body));
});