title: expressJS: Limit acceptable content-types
body: <p>I have a expressJS API. In POST routes, I only accept two types of headers:</p>
  
  <p><code>application/x-www-form-urlencoded</code></p>
  
  <p><code>application/json</code></p>
  
  <p>Is there a way that I can express to enforce to only accept the two headers and reject any other <code>POST</code> request and respond with some kind of 400 error?</p>