Windows connectors: add device_scan_interval arg

The Hyper-V Nova driver will pass os-brick the device rescan
interval. This change indends to honor this for the Windows
connectors.

Other connectors use either a fixed rescan interval, either a
exponentially growing interval. If needed, this patch can be
updated so that other connectors may use this argument as well.

Change-Id: I3d6b4ed2ac27269241420ca03ec7075a977e86e8

os_brick/initiator/windows/base.py

@@ -29,9 +29,14 @@ class BaseWindowsConnector(initiator_connector.InitiatorConnector):
     platform = initiator.PLATFORM_ALL
     os_type = initiator.OS_TYPE_WINDOWS
 
+    DEFAULT_DEVICE_SCAN_INTERVAL = 2
+
     def __init__(self, root_helper=None, *args, **kwargs):
         super(BaseWindowsConnector, self).__init__(root_helper,
                                                    *args, **kwargs)
+        self.device_scan_interval = kwargs.pop(
+            'device_scan_interval', self.DEFAULT_DEVICE_SCAN_INTERVAL)
+
         self._diskutils = utilsfactory.get_diskutils()
 
     @staticmethod

os_brick/initiator/windows/fibre_channel.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import collections
+import time
 
 from os_win import utilsfactory
 from oslo_log import log as logging
@@ -95,6 +96,8 @@ class WindowsFCConnector(win_conn_base.BaseWindowsConnector):
             if disk_paths:
                 break
 
+            time.sleep(self.device_scan_interval)
+
         self._check_device_paths(disk_paths)
         return list(disk_paths)
 

os_brick/initiator/windows/iscsi.py

@@ -101,7 +101,12 @@ class WindowsISCSIConnector(win_conn_base.BaseWindowsConnector,
                     auth_password=connection_properties.get('auth_password'),
                     mpio_enabled=self.use_multipath,
                     initiator_name=initiator_name,
-                    rescan_attempts=self.device_scan_attempts)
+                    ensure_lun_available=False)
+                self._iscsi_utils.ensure_lun_available(
+                    target_iqn=target_iqn,
+                    target_lun=target_lun,
+                    rescan_attempts=self.device_scan_attempts,
+                    retry_interval=self.device_scan_interval)
 
                 if not volume_connected:
                     (device_number,

os_brick/tests/windows/test_fibre_channel.py

@@ -25,7 +25,8 @@ from os_brick.tests.windows import test_base
 class WindowsFCConnectorTestCase(test_base.WindowsConnectorTestBase):
     def setUp(self):
         super(WindowsFCConnectorTestCase, self).setUp()
-        self._connector = fc.WindowsFCConnector()
+        self._connector = fc.WindowsFCConnector(
+            device_scan_interval=mock.sentinel.rescan_interval)
 
         self._diskutils = self._connector._diskutils
         self._fc_utils = self._connector._fc_utils
@@ -92,10 +93,12 @@ class WindowsFCConnectorTestCase(test_base.WindowsConnectorTestBase):
                                    dict(device_name=mock.sentinel.disk_path)],
                'expected_paths': [mock.sentinel.disk_path]})
     @ddt.unpack
+    @mock.patch('time.sleep')
     @mock.patch.object(fc.WindowsFCConnector, '_get_fc_volume_mappings')
     @mock.patch.object(fc.WindowsFCConnector, '_check_device_paths')
     def test_get_volume_paths(self, mock_check_device_paths,
                               mock_get_fc_mappings,
+                              mock_sleep,
                               volume_mappings, expected_paths):
         mock_get_fc_mappings.return_value = volume_mappings
 
@@ -113,6 +116,9 @@ class WindowsFCConnectorTestCase(test_base.WindowsConnectorTestBase):
             [mock.call(mock.sentinel.conn_props)] * expected_try_count)
         mock_check_device_paths.assert_called_once_with(
             set(vol_paths))
+        mock_sleep.assert_has_calls(
+            [mock.call(mock.sentinel.rescan_interval)] *
+            (expected_try_count - 1))
 
     @mock.patch.object(fc.WindowsFCConnector, '_get_fc_hba_mappings')
     def test_get_fc_volume_mappings(self, mock_get_fc_hba_mappings):

os_brick/tests/windows/test_iscsi.py

@@ -31,7 +31,8 @@ class WindowsISCSIConnectorTestCase(test_base.WindowsConnectorTestBase):
         self._diskutils = mock.Mock()
         self._iscsi_utils = mock.Mock()
 
-        self._connector = iscsi.WindowsISCSIConnector()
+        self._connector = iscsi.WindowsISCSIConnector(
+            device_scan_interval=mock.sentinel.rescan_interval)
         self._connector._diskutils = self._diskutils
         self._connector._iscsi_utils = self._iscsi_utils
 
@@ -128,9 +129,15 @@ class WindowsISCSIConnectorTestCase(test_base.WindowsConnectorTestBase):
                        auth_password=mock.sentinel.auth_password,
                        mpio_enabled=use_multipath,
                        initiator_name=mock.sentinel.initiator_name,
-                       rescan_attempts=(
-                           self._connector.device_scan_attempts))] *
+                       ensure_lun_available=False)] *
             expected_login_attempts)
+        self._iscsi_utils.ensure_lun_available.assert_has_calls(
+            [mock.call(target_iqn=mock.sentinel.target_iqn,
+                       target_lun=mock.sentinel.target_lun,
+                       rescan_attempts=(
+                           self._connector.device_scan_attempts),
+                       retry_interval=mock.sentinel.rescan_interval)] *
+            (expected_login_attempts - 1))
 
         self._iscsi_utils.get_device_number_and_path.assert_called_once_with(
             mock.sentinel.target_iqn, mock.sentinel.target_lun)