[k8s] Fix resources.image_id backward compatibility

sky/clouds/kubernetes.py

@@ -41,6 +41,8 @@ class Kubernetes(clouds.Cloud):
     SKY_SSH_KEY_SECRET_NAME = 'sky-ssh-keys'
     SKY_SSH_JUMP_NAME = 'sky-ssh-jump-pod'
 
+    LEGACY_SINGLETON_REGION = 'kubernetes'
+
     # Limit the length of the cluster name to avoid exceeding the limit of 63
     # characters for Kubernetes resources. We limit to 42 characters (63-21) to
     # allow additional characters for creating ingress services to expose ports.
@@ -54,7 +56,6 @@ class Kubernetes(clouds.Cloud):
     _DEFAULT_MEMORY_CPU_RATIO = 1
     _DEFAULT_MEMORY_CPU_RATIO_WITH_GPU = 4  # Allocate more memory for GPU tasks
     _REPR = 'Kubernetes'
-    _LEGACY_SINGLETON_REGION = 'kubernetes'
     _CLOUD_UNSUPPORTED_FEATURES = {
         # TODO(romilb): Stopping might be possible to implement with
         #  container checkpointing introduced in Kubernetes v1.25. See:
@@ -630,7 +631,7 @@ def instance_type_exists(self, instance_type: str) -> bool:
             instance_type)
 
     def validate_region_zone(self, region: Optional[str], zone: Optional[str]):
-        if region == self._LEGACY_SINGLETON_REGION:
+        if region == self.LEGACY_SINGLETON_REGION:
             # For backward compatibility, we allow the region to be set to the
             # legacy singleton region.
             # TODO: Remove this after 0.9.0.

sky/resources.py

@@ -45,7 +45,7 @@ class Resources:
     """
     # If any fields changed, increment the version. For backward compatibility,
     # modify the __setstate__ method to handle the old version.
-    _VERSION = 19
+    _VERSION = 20
 
     def __init__(
         self,
@@ -1607,4 +1607,25 @@ def __setstate__(self, state):
             self._cluster_config_overrides = state.pop(
                 '_cluster_config_overrides', None)
 
+        if version < 20:
+            # Pre-0.7.0, we used 'kubernetes' as the default region for
+            # Kubernetes clusters. With the introduction of support for
+            # multiple contexts, we now set the region to the context name.
+            # Since we do not have information on which context the cluster
+            # was run in, we default it to the current active context.
+            legacy_region = clouds.Kubernetes().LEGACY_SINGLETON_REGION
+            original_cloud = state.get('_cloud', None)
+            original_region = state.get('_region', None)
+            if (clouds.Kubernetes().is_same_cloud(original_cloud) and
+                    original_region == legacy_region):
+                current_context = (
+                    kubernetes_utils.get_current_kube_config_context_name())
+                state['_region'] = current_context
+                # Also update the image_id dict if it contains the old region
+                if isinstance(state['_image_id'], dict):
+                    if legacy_region in state['_image_id']:
+                        state['_image_id'][current_context] = (
+                            state['_image_id'][legacy_region])
+                        del state['_image_id'][legacy_region]
+
         self.__dict__.update(state)