title: React-Admin is populating my <List> with same element
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  <p>I'm trying to create a nice admin dashboard with <code>react-admin</code>.<br/>As using <code>spring</code> in my backend and this is how am sending data to <code>react-admin</code>:</p>
  
  <pre class="lang-java prettyprint-override"><code>@GetMapping("admin/user")
  ResponseEntity&lt;List&lt;User&gt;&gt; getAll()
  {
     System.out.println(new Date());;
  
     HttpHeaders responseHeaders = new HttpHeaders();
          responseHeaders.set("Content-Range", "posts 0-"+userRepository.findAll().size() + "/" + userRepository.findAll().size());
          responseHeaders.set("Origin", "http://localhost:3001");
  
      return ResponseEntity.ok()
               .headers(responseHeaders)
               .body(userRepository.findAll());
  }
  </code></pre>
  
  <p><em>First of all this is not working and secondly, this is not even close to correct solution</em>.<br/></p>
  
  <p>Unfortunately, my client renders the last thing over and over again.<br/>
  As you can see <strong>below</strong>, element with <code>id 129</code> is rendered over and over again!</p>
  
  <p><a href="https://i.stack.imgur.com/ktgYJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ktgYJ.png" alt="react-admin populating list with same element"></a></p>
  
  <p>At the frontend, within <code>react.js</code>:</p>
  
  <pre class="lang-js prettyprint-override"><code>// Within main/parent component
  class App extends Component {
    render() {
      return (
        &lt;Admin dataProvider={restProvider('http://localhost:8080/admin')}&gt;
           &lt;Resource name="user" list={UserList}/&gt;
        &lt;/Admin&gt;
      );
    }
  };
  
  // child component
  const UserList = (props) =&gt; (
     &lt;List {...props}&gt;
        &lt;Datagrid&gt;
           &lt;TextField source="userID" /&gt;
           &lt;TextField source="username" /&gt;
           &lt;TextField source="firstName" /&gt;
           &lt;TextField source="middleName" /&gt;
           &lt;TextField source="lastName" /&gt;
           &lt;TextField source="profileImageURL" /&gt;
           &lt;DateField source="joiningTime" /&gt;
           &lt;EditButton basePath="/posts" /&gt;
         &lt;/Datagrid&gt;
      &lt;/List&gt;
  );
  </code></pre>
  
  <p><em>I think I need a method that sort of configures every controller response with a <code>Content-Range</code> header</em>.</p>
  
  <p>Please note that my returned data works fine in <code>postman</code>: </p>
  
  <p><a href="https://i.stack.imgur.com/IP9FW.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IP9FW.png" alt="react-admin populating list with same element"></a></p>