curl -X POST "https://api.swoogo.com/api/v1/registrants/checkin" \
  -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
  -H "Content-Type: multipart/form-data" \
  -F "id=26361060" \
  -F "status=attended"

import requests

url = "https://api.swoogo.com/api/v1/registrants/checkin"

payload = "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"id\"\r\n\r\n26361060\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"status\"\r\n\r\nattended\r\n-----011000010111000001101001--"
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "multipart/form-data; boundary=---011000010111000001101001"
}

response = requests.post(url, data=payload, headers=headers)

print(response.text)

const form = new FormData();
form.append('id', '26361060');
form.append('status', 'attended');

const options = {method: 'POST', headers: {Authorization: 'Bearer <token>'}};

options.body = form;

fetch('https://api.swoogo.com/api/v1/registrants/checkin', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.swoogo.com/api/v1/registrants/checkin",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"id\"\r\n\r\n26361060\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"status\"\r\n\r\nattended\r\n-----011000010111000001101001--",
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: multipart/form-data; boundary=---011000010111000001101001"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.swoogo.com/api/v1/registrants/checkin"

	payload := strings.NewReader("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"id\"\r\n\r\n26361060\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"status\"\r\n\r\nattended\r\n-----011000010111000001101001--")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "multipart/form-data; boundary=---011000010111000001101001")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.swoogo.com/api/v1/registrants/checkin")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "multipart/form-data; boundary=---011000010111000001101001")
  .body("-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"id\"\r\n\r\n26361060\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"status\"\r\n\r\nattended\r\n-----011000010111000001101001--")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.swoogo.com/api/v1/registrants/checkin")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'multipart/form-data; boundary=---011000010111000001101001'
request.body = "-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"id\"\r\n\r\n26361060\r\n-----011000010111000001101001\r\nContent-Disposition: form-data; name=\"status\"\r\n\r\nattended\r\n-----011000010111000001101001--"

response = http.request(request)
puts response.read_body

{
  "id": 1,
  "status": "Attended",
  "updated_at": "2015-09-28 10:35:21"
}