String requestData = "{\"document\":{\"id\":\"10001\"}}";

OkHttpClient client = new OkHttpClient().newBuilder()
  .build();

MediaType mediaType = MediaType.parse("application/json");

RequestBody body = RequestBody.create(mediaType, requestData);

Request request = new Request.Builder()
  .url("https://doc.signok.com/api/v1/document/send")
  .method("POST", body)
  .addHeader("Content-Type", "application/json")
  .addHeader("Authorization", "Bearer ACCESS_TOKEN")
  .build();

Response response = client.newCall(request).execute();

var requestData = "{\"document\":{\"id\":\"10001\"}}";

var client = new RestClient("https://doc.signok.com/api/v1/document/send");
client.Timeout = -1;

var request = new RestRequest(Method.POST);
request.AddHeader("Content-Type", "application/json");
request.AddHeader("Authorization", "Bearer ACCESS_TOKEN");
request.AddParameter("application/json", requestData,  ParameterType.RequestBody);

IRestResponse response = client.Execute(request);

Console.WriteLine(response.Content);

var requestData = "{\"document\":{\"id\":\"10001\"}}";

var myHeaders = new Headers();
myHeaders.append("Content-Type", "application/json");
myHeaders.append("Authorization", "Bearer ACCESS_TOKEN");

var requestOptions = {
  method: "POST",
  headers: myHeaders,
  body: requestData,
  redirect: "follow"
};

fetch("https://doc.signok.com/api/v1/document/send", requestOptions)
  .then(response => response.text())
  .then(result => console.log(result))
  .catch(error => console.log("error", error));

var requestData = "{\"document\":{\"id\":\"10001\"}}";

var axios = require("axios");

var config = {
  method: "POST",
  url: "https://doc.signok.com/api/v1/document/send",
  headers: {
    "Content-Type": "application/json",
    "Authorization": "Bearer ACCESS_TOKEN"
  },
  data : requestData
};

axios(config)
  .then(function (response) {
    console.log(JSON.stringify(response.data));
  })
  .catch(function (error) {
    console.log(error);
  });

import http.client

requestData = "{\"document\":{\"id\":\"10001\"}}"

conn = http.client.HTTPSConnection("doc.signok.com")
headers = {
  "Content-Type": "application/json",
  "Authorization": "Bearer ACCESS_TOKEN"
}

conn.request("POST", "/api/v1/document/send", requestData, headers)

res = conn.getresponse()

data = res.read()

print(data.decode("utf-8"))