strapi/public/app/utils/request.js

import 'whatwg-fetch';

/**
 * Parses the JSON returned by a network request
 *
 * @param  {object} response A response from a network request
 *
 * @return {object}          The parsed JSON from the request
 */
function parseJSON(response) {
  return response.json();
}

/**
 * Checks if a network request came back fine, and throws an error if not
 *
 * @param  {object} response   A response from a network request
 *
 * @return {object|undefined} Returns either the response, or throws an error
 */
function checkStatus(response) {
  return new Promise((resolve, reject) => {
    if (response.status >= 200 && response.status < 300) {
      return resolve(response);
    }

    parseJSON(response)
      .then(data => {
        const error = new Error(data.message || response.statusText);
        error.data = data;
        error.response = response;
        throw error;
      })
      .catch(err => {
        reject(err);
      });
  });
}

/**
 * Requests a URL, returning a promise
 *
 * @param  {string} url       The URL we want to request
 * @param  {object} [options] The options we want to pass to "fetch"
 *
 * @return {object}           An object containing either "data" or "err"
 */
export default function request(url, options) {
  // Default headers
  options = options || {};
  options.headers = options && options.headers || {
    'Accept': 'application/json',
      'Content-Type': 'application/json'
  };

  return fetch(url, options)
    .then(checkStatus)
    .then(parseJSON)
    .then((data) => ({ data }))
    .catch((err) => ({ err }));
}