title: Headers not showing in fetch response
body: <p>I can see the header "x-auth-token" in Chrome DevTools.
  <a href="https://i.stack.imgur.com/dIh0y.png" rel="noreferrer"><img src="https://i.stack.imgur.com/dIh0y.png" alt="enter image description here"></a></p>
  
  <p>However, the header is not showing up in my fetch response.
  Please assist so I can use header data.</p>
  
  <p>I am using NodeJS as my backend API and ReactJS as my front-end.
  These are my files.</p>
  
  <p>NodeJS middleware - cors.js</p>
  
  <pre><code>module.exports = function enableCorsSupport(app) {
    app.use(function(req, res, next) {
      res.header("Access-Control-Allow-Origin", "*");
      res.header("Access-Control-Allow-Methods", "POST, GET, PUT, DELETE");
      res.header("Access-Control-Allow-Headers", "Content-Type, x-auth-token");
      res.header("Access-Control-Expose-Headers", "x-auth-token");
      next();
    })
  }
  </code></pre>
  
  <p>NodeJS route - users.js</p>
  
  <pre><code>router.post('/login', async (req, res) =&gt; {
  
    // NOTE: code left out so post would be smaller
  
    const token = user.generateAuthToken();
    res.header('x-auth-token', token).send(_.pick(user, ['_id', 'firstName', 'email', 'isAdmin']));
  })
  </code></pre>
  
  <p>ReactJS - my fetch request</p>
  
  <pre><code>fetch('http://localhost:4000/api/users/login', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        email: this.props.email,
        password: this.props.password
      })
    })
    .then(res =&gt; {
      console.log('res.headers', res.headers)
      return res.json()
    })
    .then(data =&gt; {
      console.log(data);
    })
    .catch((err) =&gt; {
      console.log(err)
    })
  }
  </code></pre>
  
  <p>This is in my Chrome console from the console.log in my successful fetch request. Headers are empty in the header response. Please advise. FYI this is user test data.
  <a href="https://i.stack.imgur.com/u3Nzc.png" rel="noreferrer"><img src="https://i.stack.imgur.com/u3Nzc.png" alt="enter image description here"></a></p>