feat: Decouple NamedService from the transport feature (#969)

Co-authored-by: Eliza Weisman <eliza@buoyant.io>

Author: olix0r

tonic-build/src/server.rs

@@ -35,7 +35,7 @@ pub fn generate<T: Service>(
         if package.is_empty() { "" } else { "." },
         service.identifier()
     );
-    let transport = generate_transport(&server_service, &server_trait, &path);
+    let named = generate_named(&server_service, &server_trait, &path);
     let mod_attributes = attributes.for_mod(package);
     let struct_attributes = attributes.for_struct(&path);
 
@@ -160,7 +160,7 @@ pub fn generate<T: Service>(
                 }
             }
 
-            #transport
+            #named
         }
     }
 }
@@ -256,30 +256,20 @@ fn generate_trait_methods<T: Service>(
     stream
 }
 
-#[cfg(feature = "transport")]
-fn generate_transport(
+fn generate_named(
     server_service: &syn::Ident,
     server_trait: &syn::Ident,
     service_name: &str,
 ) -> TokenStream {
     let service_name = syn::LitStr::new(service_name, proc_macro2::Span::call_site());
 
     quote! {
-        impl<T: #server_trait> tonic::transport::NamedService for #server_service<T> {
+        impl<T: #server_trait> tonic::server::NamedService for #server_service<T> {
             const NAME: &'static str = #service_name;
         }
     }
 }
 
-#[cfg(not(feature = "transport"))]
-fn generate_transport(
-    _server_service: &syn::Ident,
-    _server_trait: &syn::Ident,
-    _service_name: &str,
-) -> TokenStream {
-    TokenStream::new()
-}
-
 fn generate_methods<T: Service>(
     service: &T,
     proto_path: &str,

tonic/src/server/mod.rs

@@ -15,3 +15,12 @@ pub use self::grpc::Grpc;
 pub use self::service::{
     ClientStreamingService, ServerStreamingService, StreamingService, UnaryService,
 };
+
+/// A trait to provide a static reference to the service's
+/// name. This is used for routing service's within the router.
+pub trait NamedService {
+    /// The `Service-Name` as described [here].
+    ///
+    /// [here]: https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests
+    const NAME: &'static str;
+}

tonic/src/transport/server/mod.rs

@@ -10,6 +10,7 @@ mod tls;
 mod unix;
 
 pub use super::service::Routes;
+pub use crate::server::NamedService;
 pub use conn::{Connected, TcpConnectInfo};
 #[cfg(feature = "tls")]
 pub use tls::ServerTlsConfig;
@@ -123,15 +124,6 @@ pub struct Router<L = Identity> {
     routes: Routes,
 }
 
-/// A trait to provide a static reference to the service's
-/// name. This is used for routing service's within the router.
-pub trait NamedService {
-    /// The `Service-Name` as described [here].
-    ///
-    /// [here]: https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests
-    const NAME: &'static str;
-}
-
 impl<S: NamedService, T> NamedService for Either<S, T> {
     const NAME: &'static str = S::NAME;
 }