title: Limiting file size in FormFile
body: <p>I'm letting users upload a file using FormFile.  At what point should I check if the file size is too large.  When I do</p>
  <pre><code> file, header, fileErr := r.FormFile(&quot;file&quot;)
  </code></pre>
  <p>A file object is already created.  So have I incurred the cost of reading in the entire file already?</p>
  <p><a href="https://golang.org/pkg/net/http#Request.FormFile" rel="nofollow noreferrer">https://golang.org/pkg/net/http#Request.FormFile</a></p>