neater

src/client.rs

@@ -600,10 +600,9 @@ impl ClientInner {
 
     async fn send<T: ServiceRequest>(&self, service_req: T) -> Result<T::Response, ClientError> {
         let basin_header = match (&self.kind, &self.config.endpoints.basin) {
-            (ClientKind::Basin(basin), BasinEndpoint::CellKnown(_)) => Some((
-                AsciiMetadataKey::from_static("S2-Basin"),
-                AsciiMetadataValue::from_str(&basin).expect("valid"),
-            )),
+            (ClientKind::Basin(basin), BasinEndpoint::CellKnown(_)) => {
+                Some((AsciiMetadataValue::from_str(&basin).expect("valid"),))
+            }
             _ => None,
         };
         send_request(service_req, &self.config.token, basin_header).await

src/service.rs

@@ -17,7 +17,7 @@ use crate::{client::ClientError, types};
 pub async fn send_request<T: ServiceRequest>(
     mut service: T,
     token: &SecretString,
-    basin_header: Option<(AsciiMetadataKey, AsciiMetadataValue)>,
+    basin_header: Option<AsciiMetadataValue>,
 ) -> Result<T::Response, ClientError> {
     let req = prepare_request(&mut service, token, basin_header)?;
     match service.send(req).await {
@@ -29,12 +29,13 @@ pub async fn send_request<T: ServiceRequest>(
 fn prepare_request<T: ServiceRequest>(
     service: &mut T,
     token: &SecretString,
-    basin_header: Option<(AsciiMetadataKey, AsciiMetadataValue)>,
+    basin_header: Option<AsciiMetadataValue>,
 ) -> Result<tonic::Request<T::ApiRequest>, types::ConvertError> {
     let mut req = service.prepare_request()?;
     add_authorization_header(req.metadata_mut(), token)?;
-    if let Some((key, value)) = basin_header {
-        req.metadata_mut().insert(key, value);
+    if let Some(basin) = basin_header {
+        req.metadata_mut()
+            .insert(AsciiMetadataKey::from_static("s2-basin"), basin);
     }
     Ok(req)
 }