[Server call] Class for create server-requests, based on fetch #js

server_call.js

// Server.call('GET',  'getVkData',  { id: -145636 })
// Server.call('POST', 'postVkData', { id: -145636 })

const MAIN_API_PATH = "http://dune.com/bar/";

class Server {
  static call(httpMethod, apiMethod, params = {}) {
    let fetchParams = {
      headers: { "Content-Type": "application/json" },
      mode: "cors",
      method: httpMethod
    };

    let urlParams = "";
    if (httpMethod === "POST") {
      fetchParams.body = JSON.stringify(params);
    } else {
      Object.keys(params).forEach(key => {
        urlParams += (urlParams ? "&" : "") + (key + "=" + params[key]);
      });
      urlParams = urlParams ? "?" + urlParams : "";
    }

    return fetch(
      MAIN_API_PATH + apiMethod + urlParams,
      fetchParams
    ).then(function(response) {
      return response.json();
    });
  }
}

export default Server;