Merge "Add sync() command to the standby module"

ironic_python_agent/extensions/standby.py

@@ -374,3 +374,17 @@ class StandbyExtension(base.BaseAgentExtension):
     def power_off(self):
         LOG.info('Powering off system')
         self._run_shutdown_script('-h')
+
+    @base.sync_command('sync')
+    def sync(self):
+        """Flush file system buffers forcing changed blocks to disk.
+
+        :raises: CommandExecutionError if flushing file system buffers fails.
+        """
+        LOG.debug('Flushing file system buffers')
+        try:
+            utils.execute('sync')
+        except processutils.ProcessExecutionError as e:
+            error_msg = 'Flushing file system buffers failed. Error: %s' % e
+            LOG.error(error_msg)
+            raise errors.CommandExecutionError(error_msg)

ironic_python_agent/tests/unit/extensions/test_standby.py

@@ -760,6 +760,19 @@ class TestStandbyExtension(test_base.BaseTestCase):
         execute_mock.assert_called_once_with(*command, check_exit_code=[0])
         self.assertEqual('FAILED', failed_result.command_status)
 
+    @mock.patch('ironic_python_agent.utils.execute', autospec=True)
+    def test_sync(self, execute_mock):
+        result = self.agent_extension.sync()
+        execute_mock.assert_called_once_with('sync')
+        self.assertEqual('SUCCEEDED', result.command_status)
+
+    @mock.patch('ironic_python_agent.utils.execute', autospec=True)
+    def test_sync_error(self, execute_mock):
+        execute_mock.side_effect = processutils.ProcessExecutionError
+        self.assertRaises(
+            errors.CommandExecutionError, self.agent_extension.sync)
+        execute_mock.assert_called_once_with('sync')
+
     @mock.patch('ironic_python_agent.extensions.standby._write_image',
                 autospec=True)
     @mock.patch('ironic_python_agent.extensions.standby._download_image',

releasenotes/notes/new-sync-command-6f5fa55df2fd5903.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - Add a new sync() command to the standby extension. When invoked,
+    the new command is responsible for flushing the file system buffers
+    to the disk.