Export GrpcWeb

[aarashy]

Motivation

I was trying to write a subroutine like the following:

pub fn grpc_web_enable<S>(service: S) -> GrpcWeb<S>
where
    S: Service<http::Request<hyper::Body>, Response = http::Response<BoxBody>>,
    S: NamedService + Clone + Send + 'static,
    S::Future: Send + 'static,
    S::Error: Into<Box<dyn std::error::Error + Send + Sync>> + Send,
{
    let web_config =
        tonic_web::Config::default().expose_headers(["grpc-status-details-bin"].into_iter());
    web_config.enable(service)
}

But because GrpcWeb isn't exported, this is impossible. It's also not good enough to return an impl Trait Object, because, when you try to call add_service on the output, you will run into rust-lang/rust#52662 (there is a required trait bound on the associated Future of the Service which cannot be set)

Solution

GrpcWeb is already a pub struct, it was just part of a hidden mod.

The Config::enable function is a pub function which returns a private struct. I generally think any struct returned by a pub function should be a pub struct - even if all of its fields and methods are private.

[LucioFranco]

#1123 will include this change, going to close this thanks for the help!