Poor UX when attempting to apply http-types typed headers

[Fishrock123]

This is not very nice:

    let authz = BasicAuth::new("any", &api_key);
    let res = client.put(&path)
        .header(authz.name(), authz.value())

(From https://github.com/squamishaccess/squamishaccess-signup-function-rs/blob/6c445916760a4db21da80c732fbe8e9c704c1bd1/src/main.rs#L168-L172)

I think something like ToHeaderPair may be ideal? We could implement that for a tuple and for typed headers.

    let authz = BasicAuth::new("any", &api_key);
    let res = client.put(&path)
        .header(authz)
        // OR
        .header((authz.name(), authz.value()))

This would be different than ToHeaderValues since it would also have the header name.

@yoshuawuyts thoughts?

[Fishrock123]

Notes:

• We could have RequestBuilder impl AsMut<Headers> but this still breaks the chaining pattern.
• This issue also exists for tide::ResponseBuilder.

[yoshuawuyts]

I don't think it's too bad for the low level API exposed from http-types — it does what it needs to. Though I def agree this is not a great end user API, and we should def look to improve.

Instead I'd be curious what we could do at the Surf level to make this nicer. Could there be some simple middleware that would make this intuitive to use? We talked about a cookie store middleware a while ago too. Perhaps a pairing there could create a nice end-user API?

[Fishrock123]

I don't follow, why should someone have to install a middleware to set typed headers easily? This is not just about auth.

[Fishrock123]

Just to be clear, my suggestion here is to hopefully avoid something like: .header() & .header_typed() or .header_parts() & .header(Typed). Although I suppose the latter wouldn't be terrible, but also not much better than today.

[jbr]

I concur on this general problem but figured we'd sort this out after most of the headers were defined. It would be nice if there was a trait of some sort that all of these headers conformed to, and a way to invert applying the headers. so instead of header.apply(&mut request), we'd request.something(header), where header is impl Header, and which sets both the name and value(s)

[Fishrock123]

For posterity, tracking issue for typed headers progress: https://github.com/http-rs/http-types/issues/99