Use dynamic build for Manager class

Signed-off-by: mulhern <[email protected]>

Author: mulkieran

pyproject.toml

@@ -1,3 +1,6 @@
 [build-system]
 requires = ["setuptools"]
 build-backend = "setuptools.build_meta"
+
+[tool.pylint]
+good-names="Manager"

src/stratis_cli/_actions/_dynamic.py

@@ -0,0 +1,56 @@
+# Copyright 2023 Red Hat, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Dynamic class generation
+"""
+# isort: STDLIB
+import os
+import xml.etree.ElementTree as ET  # nosec B405
+from enum import Enum
+
+# isort: FIRSTPARTY
+from dbus_python_client_gen import DPClientGenerationError, make_class
+
+from .._errors import StratisCliGenerationError
+from ._constants import MANAGER_INTERFACE
+from ._environment import get_timeout
+from ._introspect import SPECS
+
+DBUS_TIMEOUT_SECONDS = 120
+
+TIMEOUT = get_timeout(
+    os.environ.get("STRATIS_DBUS_TIMEOUT", DBUS_TIMEOUT_SECONDS * 1000)
+)
+
+
+class ClassKey(Enum):
+    """
+    Keys for dynamically generated classes.
+    """
+
+    MANAGER = ("Manager", MANAGER_INTERFACE)
+
+
+def make_dyn_class(key):
+    """
+    Dynamically generate a class from introspection specification.
+    """
+    try:
+        return make_class(
+            key.value[0], ET.fromstring(SPECS[key.value[1]]), TIMEOUT  # nosec B314
+        )
+    except DPClientGenerationError as err:  # pragma: no cover
+        raise StratisCliGenerationError(
+            "Failed to generate some class needed for invoking dbus-python methods"
+        ) from err

src/stratis_cli/_actions/_top.py

@@ -33,6 +33,7 @@
 from .._stratisd_constants import ReportKey, StratisdErrors
 from ._connection import get_object
 from ._constants import TOP_OBJECT
+from ._dynamic import ClassKey, make_dyn_class
 from ._formatting import print_table
 
 
@@ -44,8 +45,7 @@ def _fetch_keylist(proxy):
     :rtype: list of str
     :raises StratisCliEngineError:
     """
-    # pylint: disable=import-outside-toplevel
-    from ._data import Manager
+    Manager = make_dyn_class(ClassKey.MANAGER)
 
     (keys, return_code, message) = Manager.Methods.ListKeys(proxy, {})
     if return_code != StratisdErrors.OK:  # pragma: no cover
@@ -68,8 +68,7 @@ def _add_update_key(proxy, key_desc, capture_key, *, keyfile_path):
     """
     assert capture_key == (keyfile_path is None)
 
-    # pylint: disable=import-outside-toplevel
-    from ._data import Manager
+    Manager = make_dyn_class(ClassKey.MANAGER)
 
     if capture_key:
         password = getpass(prompt="Enter key data followed by the return key: ")
@@ -127,7 +126,7 @@ def get_report(namespace):
 
         else:
             if namespace.report_name == ReportKey.ENGINE_STATE.value:
-                from ._data import Manager
+                Manager = make_dyn_class(ClassKey.MANAGER)
 
                 (report, return_code, message) = Manager.Methods.EngineStateReport(
                     get_object(TOP_OBJECT), {}
@@ -242,8 +241,7 @@ def unset_key(namespace):
         :raises StratisCliNoChangeError:
         :raises StratisCliIncoherenceError:
         """
-        # pylint: disable=import-outside-toplevel
-        from ._data import Manager
+        Manager = make_dyn_class(ClassKey.MANAGER)
 
         proxy = get_object(TOP_OBJECT)