title: Phoenix/Elixir: CSRF with frontend application
body: <p>I'm using <a href="/questions/tagged/nuxt" class="post-tag" title="show questions tagged &#39;nuxt&#39;" rel="tag">nuxt</a> for front-end, phoenix/elixir for API server, and nginx for reverse-proxy.</p>
  
  <p>I've hit the wall when I tried to make a form for uploading files.
  How do I work with the <code>csrf</code>?</p>