Is it possible to set a "binary" header?

[Solid-Water-Dynamic]

Hello, it seems like the value of a header with its name ending with -bin is Base64 encoded when it's sent over the network.
For such a binary header, is it possible to set the value without Evans doing Base64 encoding?
Or, is there a way to specify binary header's value? I tried \x or \u but they do not seem to work.

Thanks!

[ktr0731]

Hi. Unfortunately, we can't send binary header values directly. Its behavior is based on the gRPC spec.
According to PROTOCOL-HTTP2.md, it says:

Note that HTTP2 does not allow arbitrary octet sequences for header values so binary header values must be encoded using Base64 as per https://tools.ietf.org/html/rfc4648#section-4. Implementations MUST accept padded and un-padded values and should emit un-padded values. Applications define binary headers by having their names end with "-bin". Runtime libraries use this suffix to detect binary headers and properly apply base64 encoding & decoding as headers are sent and received.

So, we can neither send binary header values directly nor -bin-prefixed headers without Base64 encoding.

[Solid-Water-Dynamic]

Thanks for the prompt answer, @ktr0731