implement unsafe deletion, and wire it

- implement unsafe deletion, and wire it
- aggregate corrupt object error(s) from the storage LIST operation
- extend storage error:
a) add a new type ErrCodeCorruptObj to represent a corrupt object:
b) add a new member 'InnerErr error' to StorageError to hold
   the inner error
- add API status error

Kubernetes-commit: 5d4b4a160dc551dc8979012eeabea1a098945603

Author: tkashem

pkg/api/errors/errors.go

@@ -54,6 +54,7 @@ var knownReasons = map[metav1.StatusReason]struct{}{
 	metav1.StatusReasonGone:                  {},
 	metav1.StatusReasonInvalid:               {},
 	metav1.StatusReasonServerTimeout:         {},
+	metav1.StatusReasonStoreReadError:        {},
 	metav1.StatusReasonTimeout:               {},
 	metav1.StatusReasonTooManyRequests:       {},
 	metav1.StatusReasonBadRequest:            {},
@@ -775,6 +776,12 @@ func IsUnexpectedObjectError(err error) bool {
 	return err != nil && (ok || errors.As(err, &uoe))
 }
 
+// IsStoreReadError determines if err is due to either failure to transform the
+// data from the storage, or failure to decode the object appropriately.
+func IsStoreReadError(err error) bool {
+	return ReasonForError(err) == metav1.StatusReasonStoreReadError
+}
+
 // SuggestsClientDelay returns true if this error suggests a client delay as well as the
 // suggested seconds to wait, or false if the error does not imply a wait. It does not
 // address whether the error *should* be retried, since some errors (like a 3xx) may

pkg/apis/meta/v1/types.go

@@ -931,6 +931,22 @@ const (
 	// Status code 500
 	StatusReasonServerTimeout StatusReason = "ServerTimeout"
 
+	// StatusReasonStoreReadError means that the server encountered an error while
+	// retrieving resources from the backend object store.
+	// This may be due to backend database error, or because processing of the read
+	// resource failed.
+	// Details:
+	//   "kind" string - the kind attribute of the resource being acted on.
+	//   "name" string - the prefix where the reading error(s) occurred
+	//   "causes" []StatusCause
+	//      - (optional):
+	//        - "type" CauseType - CauseTypeUnexpectedServerResponse
+	//        - "message" string - the error message from the store backend
+	//        - "field" string - the full path with the key of the resource that failed reading
+	//
+	// Status code 500
+	StatusReasonStoreReadError StatusReason = "StorageReadError"
+
 	// StatusReasonTimeout means that the request could not be completed within the given time.
 	// Clients can get this response only when they specified a timeout param in the request,
 	// or if the server cannot complete the operation within a reasonable amount of time.