title: Handle a 500 response with the fetch api
body: <p>We have the following call to <code>fetch</code>. </p>
  
  <pre><code>this.http.fetch('flasher', { method: 'post', body: jsonPayload })
      .then(response =&gt; response.json())
      .then(data =&gt; console.log(data));
  </code></pre>
  
  <p>This works when we receive a 200 response but logs nothing to the console when we receive a 500 response. How do we handle a 500? </p>