handle mdadm command not available

repos/system_upgrade/common/libraries/mdraid.py

@@ -1,20 +1,26 @@
-from leapp.exceptions import StopActorExecution
 from leapp.libraries.stdlib import api, CalledProcessError, run
 
 
 def is_mdraid_dev(dev):
     """
     Check if a given device is an md (Multiple Device) device
 
-    :raises: StopActorExecution in case of error
+    It is expected that the "mdadm" command is available,
+    if it's not it is assumed the device is not an md device.
+
+    :return: True if the device is an md device, False otherwise
+    :raises CalledProcessError: If an error occurred
     """
+    fail_msg = 'Could not check if device "{}" is an md device: {}'
     try:
         result = run(['mdadm', '--query', dev])
+    except OSError as err:
+        api.current_logger().warning(fail_msg.format(dev, err))
+        return False
     except CalledProcessError as err:
-        api.current_logger().warning(
-                'Could not check if device is an md device: {}'.format(err)
-        )
-        raise StopActorExecution()
+        err.message = fail_msg.format(dev, err)
+        raise  # let the calling actor handle the exception
+
     return '--detail' in result['stdout']
 
 
@@ -23,11 +29,12 @@ def get_component_devices(raid_dev):
     Get list of component devices in an md (Multiple Device) array
 
     :return: The list of component devices or None in case of error
+    :raises ValueError: If the device is not an mdraid device
     """
     try:
         # using both --verbose and --brief for medium verbosity
         result = run(['mdadm', '--detail', '--verbose', '--brief', raid_dev])
-    except CalledProcessError as err:
+    except (OSError, CalledProcessError) as err:
         api.current_logger().warning(
             'Could not get md array component devices: {}'.format(err)
         )

repos/system_upgrade/common/libraries/tests/test_mdraid.py

@@ -58,6 +58,19 @@ def test_is_mdraid_dev(monkeypatch, dev, expected):
     assert not api.current_logger.warnmsg
 
 
+def test_is_mdraid_dev_error(monkeypatch):
+    run_mocked = RunMocked(raise_err=True)
+    monkeypatch.setattr(mdraid, 'run', run_mocked)
+    monkeypatch.setattr(api, 'current_logger', logger_mocked())
+
+    with pytest.raises(CalledProcessError) as err:
+        mdraid.is_mdraid_dev(MD_DEVICE)
+
+    assert mdraid.run.called == 1
+    expect_msg = 'Could not check if device "{}" is an md device:'.format(MD_DEVICE)
+    assert expect_msg in err.value.message
+
+
 def test_get_component_devices_ok(monkeypatch):
     run_mocked = RunMocked()
     monkeypatch.setattr(mdraid, 'run', run_mocked)
@@ -73,6 +86,9 @@ def test_get_component_devices_not_md_device(monkeypatch):
     run_mocked = RunMocked()
     monkeypatch.setattr(mdraid, 'run', run_mocked)
 
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError) as err:
         mdraid.get_component_devices(NOT_MD_DEVICE)
+
     assert mdraid.run.called == 1
+    expect_msg = 'Expected md device, but got: {}'.format(NOT_MD_DEVICE)
+    assert expect_msg in str(err.value)