feat(transport): Make service router independent from transport

tonic/Cargo.toml

@@ -32,14 +32,15 @@ tls = ["dep:rustls-pki-types", "dep:rustls-pemfile", "transport", "dep:tokio-rus
 tls-roots = ["tls-roots-common", "dep:rustls-native-certs"]
 tls-roots-common = ["tls"]
 tls-webpki-roots = ["tls-roots-common", "dep:webpki-roots"]
+router = ["dep:hyper", "dep:axum", "dep:tower"]
 transport = [
-  "dep:async-stream",
-  "dep:axum",
+  "router",
   "channel",
+  "dep:async-stream",
   "dep:h2",
-  "dep:hyper",
+  "dep:hyper", "hyper?/full",
   "dep:tokio", "tokio?/net", "tokio?/time",
-  "dep:tower",
+  "dep:tower", "tower?/balance", "tower?/buffer", "tower?/discover", "tower?/limit", "tower?/load", "tower?/make", "tower?/timeout", "tower?/util",
   "dep:hyper-timeout",
 ]
 channel = []
@@ -68,11 +69,11 @@ async-trait = {version = "0.1.13", optional = true}
 
 # transport
 h2 = {version = "0.3.24", optional = true}
-hyper = {version = "0.14.26", features = ["full"], optional = true}
+hyper = {version = "0.14.26", optional = true}
 hyper-timeout = {version = "0.4", optional = true}
 tokio = {version = "1.0.1", optional = true}
 tokio-stream = "0.1"
-tower = {version = "0.4.7", default-features = false, features = ["balance", "buffer", "discover", "limit", "load", "make", "timeout", "util"], optional = true}
+tower = {version = "0.4.7", default-features = false, optional = true}
 axum = {version = "0.6.9", default_features = false, optional = true}
 
 # rustls

tonic/src/service/mod.rs

@@ -1,6 +1,11 @@
 //! Utilities for using Tower services with Tonic.
 
 pub mod interceptor;
+#[cfg(feature = "router")]
+mod router;
 
 #[doc(inline)]
 pub use self::interceptor::{interceptor, Interceptor};
+#[doc(inline)]
+#[cfg(feature = "router")]
+pub use self::router::{Routes, RoutesBuilder};

tonic/src/transport/service/router.rs → tonic/src/service/router.rs

@@ -83,6 +83,7 @@ impl Routes {
         self
     }
 
+    #[cfg(feature = "transport")]
     pub(crate) fn prepare(self) -> Self {
         Self {
             // this makes axum perform update some internals of the router that improves perf

tonic/src/transport/server/mod.rs

@@ -9,8 +9,8 @@ mod tls;
 #[cfg(unix)]
 mod unix;
 
-pub use super::service::Routes;
-pub use super::service::RoutesBuilder;
+/// A deprecated re-export. Please use `tonic::service::{Routes, RoutesBuilder}` directly.
+pub use super::service::{Routes, RoutesBuilder};
 
 pub use conn::{Connected, TcpConnectInfo};
 #[cfg(feature = "tls")]

tonic/src/transport/service/mod.rs

@@ -6,7 +6,6 @@ pub(crate) mod executor;
 pub(crate) mod grpc_timeout;
 mod io;
 mod reconnect;
-mod router;
 #[cfg(feature = "tls")]
 mod tls;
 mod user_agent;
@@ -22,5 +21,5 @@ pub(crate) use self::io::ServerIo;
 pub(crate) use self::tls::{TlsAcceptor, TlsConnector};
 pub(crate) use self::user_agent::UserAgent;
 
-pub use self::router::Routes;
-pub use self::router::RoutesBuilder;
+/// A deprecated re-export. Please use `tonic::service::{Routes, RoutesBuilder}` directly.
+pub use crate::service::{Routes, RoutesBuilder};