curl --request POST \
  --url https://{apiBaseUrl}/v2/{sessionId}/basket/extras \
  --header 'Content-Type: application/json' \
  --data '
{
  "extraId": 1234,
  "roomId": 29449,
  "quantity": 3,
  "guestPosition": 0
}
'

const url = 'https://{apiBaseUrl}/v2/{sessionId}/basket/extras';
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({extraId: 1234, roomId: 29449, quantity: 3, guestPosition: 0})
};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));

import requests

url = "https://{apiBaseUrl}/v2/{sessionId}/basket/extras"

payload = {
    "extraId": 1234,
    "roomId": 29449,
    "quantity": 3,
    "guestPosition": 0
}
headers = {"Content-Type": "application/json"}

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

print(response.text)

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://{apiBaseUrl}/v2/{sessionId}/basket/extras",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'extraId' => 1234,
    'roomId' => 29449,
    'quantity' => 3,
    'guestPosition' => 0
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

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

curl_close($curl);

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

using RestSharp;


var options = new RestClientOptions("https://{apiBaseUrl}/v2/{sessionId}/basket/extras");
var client = new RestClient(options);
var request = new RestRequest("");
request.AddJsonBody("{\n  \"extraId\": 1234,\n  \"roomId\": 29449,\n  \"quantity\": 3,\n  \"guestPosition\": 0\n}", false);
var response = await client.PostAsync(request);

Console.WriteLine("{0}", response.Content);

HttpResponse<String> response = Unirest.post("https://{apiBaseUrl}/v2/{sessionId}/basket/extras")
  .header("Content-Type", "application/json")
  .body("{\n  \"extraId\": 1234,\n  \"roomId\": 29449,\n  \"quantity\": 3,\n  \"guestPosition\": 0\n}")
  .asString();

{
  "code": "InvalidUserAuthentication",
  "message": "<string>"
}