Better Content-Type detection in zhttp

[nDmitry]

Before you begin

• I have read the FAQ and my issue was not answered there

What version of Zog are you using

v0.16.0

Describe the bug

Some HTTP clients send values for Content-Type headers with a charset appended to it. E.g. axios (JS HTTP library) will send this header by default: Content-Type: application/json;charset=utf-8, which zhttp cannot detect using its simple switch statement. While it can be changed to just application/json on the client side, a more robust content-type detection can be implemented on Zog's part (using strings.Contains?).

To Reproduce

I think looking in the source code should be enough. Otherwise it can be reproduced using any HTTP client against a server using zhttp, just send this header: Content-Type: application/json;charset=utf-8.

Expected behavior

zhttp should detect a more complex Content-Type values with any directive specified after a semicolon following the content type.

Additional context

charset is an allowed directive in Content-Type header: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Type#directives

[Oudwins]

Good catch. Thank you.