Example

var http = require("https");

var options = {
  "method": "POST",
  "hostname": "app-x.nipamail.com",
  "port": null,
  "path": "/v1.0/transactional/post?accept_token=NPAPP-IGBmfucf0Np567WzwAH1KuRovnszt9r4HJPJ2U4SRhPk1pCeBXEi7nUkixLby8qwwwymbXwtV3gjOMeodNKlcAChYrZ0D8TQv60208fxXIZlJ7www",
  "headers": {
    "content-type": "multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW",
    "cache-control": "no-cache"
  }
};

var req = http.request(options, function (res) {
  var chunks = [];

  res.on("data", function (chunk) {
    chunks.push(chunk);
  });

  res.on("end", function () {
    var body = Buffer.concat(chunks);
    console.log(body.toString());
  });
});

req.write("------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"from_name\"\r\n\r\nThaksinai Kondee\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"from_email\"\r\n\r\nthaksinai@hotmail.com\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"to\"\r\n\r\nthaksinai@ispio.com\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"subject\"\r\n\r\nร่วมฉลอง ครบรอบการก่อตั้ง บริษัท Nipa technology วันนี้ เวลา 18:00 น.\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"message\"\r\n\r\ncontent1\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"reply_email\"\r\n\r\nse55660159@gmail.com\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW\r\nContent-Disposition: form-data; name=\"reply_name\"\r\n\r\nThakweb.com\r\n------WebKitFormBoundary7MA4YWxkTrZu0gW--");
req.end();