Add first pass at interop tests

tonic-interop/src/client.rs

@@ -0,0 +1,39 @@
+use crate::{pb::*, test_assert, TestAssertion};
+use std::net::SocketAddr;
+use tokio::net::TcpStream;
+use tonic::Request;
+use tower_h2::{add_origin::AddOrigin, Connection};
+
+pub type Client = TestServiceClient<AddOrigin<Connection<tonic::BoxBody>>>;
+
+tonic::client!(service = "grpc.testing.TestService", proto = "crate::pb");
+
+pub async fn create(addr: SocketAddr) -> Result<Client, Box<dyn std::error::Error>> {
+    let io = TcpStream::connect(&addr).await?;
+
+    let origin = http::Uri::from_shared(format!("http://{}", addr).into()).unwrap();
+
+    let svc = Connection::handshake(io).await?;
+    let svc = AddOrigin::new(svc, origin);
+
+    Ok(TestServiceClient::new(svc))
+}
+
+pub async fn unary_call(client: &mut Client, assertions: &mut Vec<TestAssertion>) {
+    let result = client.empty_call(Request::new(Empty {})).await;
+
+    assertions.push(test_assert!(
+        "call must be successful",
+        result.is_ok(),
+        format!("result={:?}", result)
+    ));
+
+    if let Ok(response) = result {
+        let body = response.into_inner();
+        assertions.push(test_assert!(
+            "body must not be null",
+            body == Empty {},
+            format!("body={:?}", body)
+        ));
+    }
+}