title: react native fetch not calling then or catch
body: <p>I am using fetch to make some API calls in react-native, sometimes randomly the fetch does not fire requests to server and my then or except blocks are not called. This happens randomly, I think there might be a race condition or something similar. After failing requests once like this, the requests to same API never get fired till I reload the app. Any ideas how to trace reason behind this. The code I used is below.</p>
  
  <pre class="lang-js prettyprint-override"><code>const host = liveBaseHost;
  const url = `${host}${route}?observer_id=${user._id}`;
  let options = Object.assign({
          method: verb
      }, params
      ? {
          body: JSON.stringify(params)
      }
      : null);
  options.headers = NimbusApi.headers(user)
  return fetch(url, options).then(resp =&gt; {
      let json = resp.json();
      if (resp.ok) {
          return json
      }
      return json.then(err =&gt; {
          throw err
      });
  }).then(json =&gt; json);
  </code></pre>