title: POST request on Heroku doesn't work
body: <p>I have the following problem.
  A web service is sending a JSON POST request to my app on Heroku and I want to parse it.</p>
  
  <p>If I look into my Heroku logs, I see that there was a POST request but it got an error</p>
  
  <pre><code>ActionController::RoutingError (No route matches....)
  </code></pre>
  
  <p>But a GET request works fine, no error.</p>
  
  <p>I'm pretty new to Rails so I don't know  what's wrong. Any ideas?</p>