title: Is it possible to control the HTTP response behavior in openCPU?
body: <p>According to <a href="https://www.opencpu.org/api.html#api-status" rel="nofollow noreferrer">the openCPU documentation</a>, there are some default HTTP status codes and return types for a few situations. For example, when R raises an error, openCPU returns code <code>400</code> with a response type of <code>text/plain</code>.</p>
  <p>While I believe it should be possible to control those things, is it possible to customize any of those things directly from R? For example, what if I wanted to return a JSON for a specific error in my R function, with a status code 503?</p>