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

Co-authored-by: Eliza Weisman <[email protected]>

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;
 }