title: Find entities containing a string in a list in Spring Data Repositories
body: <p>I do have a simple <code>MongoRepository</code> and its entities do have a <code>List&lt;String&gt; tags</code> attribute. Is there a way to add a <code>findBy</code> method to the repository? Something like</p>
  
  <pre><code>List&lt;...&gt; findByInTags(@Param("tag") String tag);
  </code></pre>
  
  <p>So all entities containing the given string <code>tag</code> in there list <code>tags</code> will be returned.</p>
  
  <p>I tried to solve it with a <code>RestController</code> and a custom <code>findByTag</code> endpoint. But I would like to use HATEOAS for the result format.</p>