add garbage auth that does not help

src/client.rs

@@ -1,12 +1,18 @@
 mod grpc;
 use tokio_stream::{self as stream};
-use tonic::Request;
+use tonic::{metadata::MetadataValue, transport::Channel, Request};
 
 use grpc::dummy::{test_service_client::TestServiceClient, Empty, SomeRequest, StreamRequest};
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let mut client = TestServiceClient::connect("http://[::1]:50051").await?;
+    let channel = Channel::from_static("http://[::1]:50051").connect().await?;
+    let token: MetadataValue<_> = "Bearer some-secret-token".parse()?;
+    let mut client = TestServiceClient::with_interceptor(channel, move |mut req: Request<_>| {
+        println!("Request: {:?}", req);
+        req.metadata_mut().insert("authorization", token.clone());
+        Ok(req)
+    });
 
     let request =
         Request::new(SomeRequest { what_client_sends: String::from("Hello from client!") });

src/server.rs

@@ -3,11 +3,12 @@ use grpc::dummy;
 use std::pin::Pin;
 use tokio_stream::{wrappers::ReceiverStream, Stream, StreamExt};
 use tonic::async_trait;
+use tonic::metadata::MetadataValue;
 use tonic::{transport::Server, Request, Response, Status};
 
 use dummy::{
-    test_service_server::{TestService, TestServiceServer},
-    Empty, SomeRequest, SomeResponse, StreamRequest, StreamResponse,
+    test_service_server::TestService, Empty, SomeRequest, SomeResponse, StreamRequest,
+    StreamResponse,
 };
 
 #[derive(Debug, Default)]
@@ -90,8 +91,20 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let service = MyTestService::default();
 
     println!("Starting gRPC server on {}", addr);
+    let service =
+        dummy::test_service_server::TestServiceServer::with_interceptor(service, check_auth);
 
-    Server::builder().add_service(TestServiceServer::new(service)).serve(addr).await?;
+    Server::builder().add_service(service).serve(addr).await?;
 
     Ok(())
 }
+
+fn check_auth(req: Request<()>) -> Result<Request<()>, Status> {
+    let token: MetadataValue<_> = "Bearer some-secret-token".parse().unwrap();
+    println!("Request: {:?}", req);
+
+    match req.metadata().get("authorization") {
+        Some(t) if token == t => Ok(req),
+        _ => Err(Status::unauthenticated("No valid auth token")),
+    }
+}