Unable to decode with compressed response from origin

[BrandonlinU]

I was working in a Api Platform app with Caddy behind a IIS server. The IIS server manages HTTP/2 and stream the headers in lowercase to the Caddy server running HTTP/1.1. According to the RFC, the HTTP/2 headers should be case-senstive and with all headers in lowercase, and the HTTP/1.1 should be case-insensitive. The code that extracts the headers only verifies the "Field" header, in a case-sensitive manner, causing that the Fields header can not be readed correctly.
I would try to test a patch, but I don't know Go, so I can't guarranty nothing.

[BrandonlinU]

After some tests I can confirm that the go http server normalize the headers to "Fields" before send it to Vulcain. The error was that Caddy does not send a uncompress response to Vulcain when the origin server return a GZipped response, so Vulcain can't decode it and return a empty object. Should I report that to the Caddy team or is responsability of each http handler to uncompress the response?