HTTPURLResponse allHeaderFields Swift 3 Capitalisation : <p>Converting to Swift 3 I noticed a strange bug occur reading a header field from HTTPURLResponse.</p>

<pre><code>let id = httpResponse.allHeaderFields["eTag"] as? String
</code></pre>

<p>no longer worked.</p>

<p>I printed out the all headers dictionary and all my header keys seem to be in Sentence case.</p>

<p>According to Charles proxy all my headers are in lower case. According to the backend team, in their code the headers are in Title-Case. According the docs: headers should be case-insensitive. </p>

<p>So I don't know which to believe. Is anyone else finding in Swift 3 that their headers are now being turned into Sentence case by iOS? If so is this behaviour we want?</p>

<p>Should I log a bug with Apple or should I just make a category on HTTPURLResponse to allow myself to case insensitively find a header value.</p>
