feat: add GrpcMethod extension into request for client (#1275)

* feat: add GrpcMethod extension into request for client

* refactor: change GrpcMethod fields into private and expose methods instead

* refactor: hide GrpcMethod::new in doc

---------

Co-authored-by: Lucio Franco <[email protected]>

tonic/src/codegen.rs

@@ -11,6 +11,7 @@ pub use std::task::{Context, Poll};
 pub use tower_service::Service;
 pub type StdError = Box<dyn std::error::Error + Send + Sync + 'static>;
 pub use crate::codec::{CompressionEncoding, EnabledCompressionEncodings};
+pub use crate::extensions::GrpcMethod;
 pub use crate::service::interceptor::InterceptedService;
 pub use bytes::Bytes;
 pub use http;

tonic/src/extensions.rs

@@ -71,3 +71,27 @@ impl fmt::Debug for Extensions {
         f.debug_struct("Extensions").finish()
     }
 }
+
+/// A gRPC Method info extension.
+#[derive(Debug)]
+pub struct GrpcMethod {
+    service: &'static str,
+    method: &'static str,
+}
+
+impl GrpcMethod {
+    /// Create a new `GrpcMethod` extension.
+    #[doc(hidden)]
+    pub fn new(service: &'static str, method: &'static str) -> Self {
+        Self { service, method }
+    }
+
+    /// gRPC service name
+    pub fn service(&self) -> &str {
+        &self.service
+    }
+    /// gRPC method name
+    pub fn method(&self) -> &str {
+        &self.method
+    }
+}

tonic/src/lib.rs

@@ -111,7 +111,7 @@ pub use async_trait::async_trait;
 
 #[doc(inline)]
 pub use codec::Streaming;
-pub use extensions::Extensions;
+pub use extensions::{Extensions, GrpcMethod};
 pub use request::{IntoRequest, IntoStreamingRequest, Request};
 pub use response::Response;
 pub use status::{Code, Status};