DisableCompression is ignored in http2 requests

[jsnjack]

When retrieving a resource via http2, fhttp library always decompresses the body, even if DisableCompression is set to true. According to the option description this should not happen:

	// DisableCompression, if true, prevents the Transport from
	// requesting compression with an "Accept-Encoding: gzip"
	// request header when the Request contains no existing
	// Accept-Encoding value. If the Transport requests gzip on
	// its own and gets a gzipped response, it's transparently
	// decoded in the Response.Body. However, if the user
	// explicitly requested gzip it is not automatically
	// uncompressed.

I looked into parts which read body in http1 and http2 and compared them. http1 has addedGzip flag which is checked before calling DecompressBody function (https://github.com/bogdanfinn/fhttp/blob/959a7f72d1ca6d6319e1ed82a26eea431658d3b3/transport.go#L2190). In http2 we have requestedGzip flag, which acts in similar way. However, requestedGzip is not checked (https://github.com/bogdanfinn/fhttp/blob/master/http2/transport.go#L2259).

The following change seem to solve the issue bogdanfinn/fhttp@8237b3b

[bogdanfinn]

@jsnjack thank you for supplying the fix for that.
will include that in the next release and i think about adding an option to the tlsclient itself to be able to set DisableCompression to either true or false.

[jsnjack]

Thanks!

By the way, tlsclient already has this option. It can be set via TransportOptions

[bogdanfinn]

https://github.com/bogdanfinn/tls-client/releases/tag/v1.3.10