fetch.js

export const api = ({ url, headers = {}, body, method }) =>
  new Promise(async (resolve, reject) => {
    try {
      body = JSON.stringify(body);
      headers['Content-Type'] = 'application/json';
    } catch (e) {}

    //intercept before if i want
    let token = await storage.get('userToken')
    headers.Authorization = token

    try {
      let response = await fetch(url, {
        headers,
        body,
        method: method || 'GET',
      });
      let json = await response.json();
      resolve(json);
    } catch (e) {
      reject(e);
    }
  });

// usage
await api({
  url: 'http://test.com',
  method: 'POST',
  body: { test: 'test json' },
});