[k8s] Fix rsync for context name with : and / (#4065)

* [kubernetes] Fix context name with colon

* comment

* remove additional /

* Move the encoding to kubernetes only

sky/utils/command_runner.py

@@ -831,10 +831,17 @@ def get_remote_home_dir() -> str:
         # Build command.
         helper_path = os.path.join(os.path.abspath(os.path.dirname(__file__)),
                                    'kubernetes', 'rsync_helper.sh')
+        namespace_context = f'{self.namespace}+{self.context}'
+        # Avoid rsync interpreting :, /, and + in namespace_context as the
+        # default delimiter for options and arguments.
+        # rsync_helper.sh will parse the namespace_context by reverting the
+        # encoding and pass it to kubectl exec.
+        encoded_namespace_context = namespace_context.replace(
+            ':', '%3A').replace('/', '%2F').replace('+', '%2B')
         self._rsync(
             source,
             target,
-            node_destination=f'{self.pod_name}@{self.namespace}+{self.context}',
+            node_destination=f'{self.pod_name}@{encoded_namespace_context}',
             up=up,
             rsh_option=helper_path,
             log_path=log_path,

sky/utils/kubernetes/rsync_helper.sh

@@ -4,9 +4,15 @@
 shift
 pod=$1
 shift
-namespace_context=$1
+echo "pod: $pod" >&2
+encoded_namespace_context=$1
+# Revert the encoded namespace+context to the original string.
+namespace_context=$(echo "$encoded_namespace_context" | sed 's|%3A|:|g' | sed 's|%2B|+|g' | sed 's|%2F|/|g')
+echo "namespace_context: $namespace_context" >&2
 namespace=$(echo $namespace_context | cut -d+ -f1)
+echo "namespace: $namespace" >&2
 context=$(echo $namespace_context | grep '+' >/dev/null && echo $namespace_context | cut -d+ -f2- || echo "")
+echo "context: $context" >&2
 context_lower=$(echo "$context" | tr '[:upper:]' '[:lower:]')
 shift
 if [ -z "$context" ] || [ "$context_lower" = "none" ]; then