Injecting container in the operator client

changelog.d/+replace-container.internal.md

@@ -0,0 +1 @@
+Operator client now injects the container into the target CRD, if one was not specified by the user.

mirrord/kube/src/resolved.rs

@@ -178,6 +178,23 @@ impl<const CHECKED: bool> ResolvedTarget<CHECKED> {
         }
     }
 
+    /// Convenient way of mutating the target container.
+    ///
+    /// # Panic
+    ///
+    /// Panics if this is a [`ResolvedTarget::Targetless`] variant.
+    pub fn container_mut(&mut self) -> &mut Option<String> {
+        match self {
+            Self::Deployment(ResolvedResource { container, .. }) => container,
+            Self::Rollout(ResolvedResource { container, .. }) => container,
+            Self::Job(ResolvedResource { container, .. }) => container,
+            Self::Pod(ResolvedResource { container, .. }) => container,
+            Self::StatefulSet(ResolvedResource { container, .. }) => container,
+            Self::CronJob(ResolvedResource { container, .. }) => container,
+            Self::Targetless(..) => panic!("targetless mode involves no target container"),
+        }
+    }
+
     /// Is this a [`ResolvedTarget::Deployment`], and is it empty?
     pub fn empty_deployment(&self) -> bool {
         if let Self::Deployment(ResolvedResource { resource, .. }) = self {

mirrord/operator/src/client.rs

@@ -611,24 +611,27 @@ impl OperatorApi<PreparedClientCert> {
                     .and_then(|copy_crd| copy_crd.creator_session.id),
             )
         } else {
-            let target = target.assert_valid_mirrord_target(self.client()).await?;
+            let mut target = target.assert_valid_mirrord_target(self.client()).await?;
 
             // `targetless` has no `RuntimeData`!
             if matches!(target, ResolvedTarget::Targetless(_)).not() {
+                // This check also ensures that the user can see at least one pod from the target set.
                 let runtime_data = target
                     .runtime_data(self.client(), target.namespace())
                     .await?;
 
                 if runtime_data.guessed_container {
                     progress.warning(
                         format!(
-                            "Target has multiple containers, mirrord picked \"{}\".\
-                     To target a different one, include it in the target path.",
+                            "Target has multiple containers, mirrord picked \"{}\". \
+                            To target a different one, include it in the target path.",
                             runtime_data.container_name
                         )
                         .as_str(),
                     );
                 }
+
+                target.container_mut().replace(runtime_data.container_name);
             }
 
             (