Change default value of namespace in task.kubernetes to be None (#43402)

* change default namespace value to be None

* passing namespace to decorator when in_cluster=False

* add breaking change

* change changelog

* revert ui change

Author: romsharon98

providers/src/airflow/providers/cncf/kubernetes/CHANGELOG.rst

@@ -27,6 +27,14 @@
 Changelog
 ---------
 
+
+main
+.....
+
+.. warning::
+  Set the default value of ``namespace`` in ``@task.kubernetes`` to ``None``, so it uses the cluster namespace when ``in_cluster`` is True. Be sure to specify a namespace when using this decorator. To retain the previous behavior, set ``namespace="default"``
+
+
 9.0.1
 .....
 

providers/src/airflow/providers/cncf/kubernetes/decorators/kubernetes.py

@@ -65,7 +65,7 @@ class _KubernetesDecoratedOperator(DecoratedOperator, KubernetesPodOperator):
     # there are some cases we can't deepcopy the objects (e.g protobuf).
     shallow_copy_attrs: Sequence[str] = ("python_callable",)
 
-    def __init__(self, namespace: str = "default", use_dill: bool = False, **kwargs) -> None:
+    def __init__(self, namespace: str | None = None, use_dill: bool = False, **kwargs) -> None:
         self.use_dill = use_dill
         super().__init__(
             namespace=namespace,

providers/src/airflow/providers/cncf/kubernetes/provider.yaml

@@ -25,6 +25,7 @@ state: ready
 source-date-epoch: 1730012271
 # note that those versions are maintained by release manager - do not update them manually
 versions:
+  - 10.0.0
   - 9.0.1
   - 9.0.0
   - 8.4.2

providers/tests/cncf/kubernetes/decorators/test_kubernetes.py

@@ -78,6 +78,7 @@ def test_basic_kubernetes(dag_maker, session, mock_create_pod: mock.Mock, mock_h
             in_cluster=False,
             cluster_context="default",
             config_file="/tmp/fake_file",
+            namespace="default",
         )
         def f():
             import random
@@ -122,6 +123,7 @@ def test_kubernetes_with_input_output(
             in_cluster=False,
             cluster_context="default",
             config_file="/tmp/fake_file",
+            namespace="default",
         )
         def f(arg1, arg2, kwarg1=None, kwarg2=None):
             return {"key1": "value1", "key2": "value2"}