title: getInitialProps in Next.js does not get data from server
body: <p>I am following <a href="https://nextjs.org/learn/basics/fetching-data-for-pages" rel="nofollow noreferrer">Next.js tutorial for fetching data</a></p>
  
  <p>But unlike tutorial, I use <code>axios</code>. Problem is <code>getInitialProps</code> does not get the data I want to have.</p>
  
  <p>here is the code:</p>
  
  <pre><code>import axios from "axios";
  import Link from "next/link";
  
  const Body = props =&gt; (
    &lt;div&gt;
      &lt;h1&gt;Shows&lt;/h1&gt;
      &lt;ul&gt;
        {props.data.map(({ show }) =&gt; (
          &lt;li key={show.id}&gt;
            &lt;Link as={`/p/${show.id}`} href={`/post?title=${show.title}`}&gt;
              &lt;a&gt;{show.name}&lt;/a&gt;
            &lt;/Link&gt;
          &lt;/li&gt;
        ))}
      &lt;/ul&gt;
    &lt;/div&gt;
  );
  
  Body.getInitialProps = async function() {
    const res = await axios.get("https://api.tvmaze.com/search/shows?q=batman");
    const data = await res.data;
    console.log(`Show data fetched. Count: ${data.length}`);
    return {
      data: data
    };
  };
  
  export default Body;
  </code></pre>
  
  <p>To me, the code seems fine but error <code>Unhandled Rejection (TypeError): Cannot read property 'map' of undefined</code> keeps occurring.</p>