From 1867b89a53e3e46394e9db80e0dc82471661068c Mon Sep 17 00:00:00 2001
From: Wenhao Xu <xuwenhao2008@gmail.com>
Date: Sun, 3 Mar 2013 01:19:08 +0800
Subject: [PATCH] Add get_volume_stats in the sheepdog driver.

1. Allow sheepdog driver to report capabilities to the scheduler.
2. add the initial test_sheepdog.py

Fixes Bug #1140162

Change-Id: I6fb1fb6714ab4ae9878b593e6eee0a94d95ef29f
---
 cinder/tests/test_sheepdog.py     | 64 +++++++++++++++++++++++++++++++
 cinder/volume/drivers/sheepdog.py | 32 ++++++++++++++++
 2 files changed, 96 insertions(+)
 create mode 100644 cinder/tests/test_sheepdog.py

diff --git a/cinder/tests/test_sheepdog.py b/cinder/tests/test_sheepdog.py
new file mode 100644
index 000000000..70fab1afd
--- /dev/null
+++ b/cinder/tests/test_sheepdog.py
@@ -0,0 +1,64 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 Wenhao Xu
+# All Rights Reserved.
+#
+#    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.
+
+from cinder import exception
+from cinder import test
+from cinder.volume.drivers.sheepdog import SheepdogDriver
+
+COLLIE_NODE_INFO = """
+0 107287605248 3623897354 3%
+Total 107287605248 3623897354 3% 54760833024
+"""
+
+
+class SheepdogTestCase(test.TestCase):
+
+    def setUp(self):
+        super(SheepdogTestCase, self).setUp()
+        self.driver = SheepdogDriver()
+
+    def test_update_volume_stats(self):
+        def fake_stats(*args):
+            return COLLIE_NODE_INFO, ''
+        self.stubs.Set(self.driver, '_execute', fake_stats)
+        expected = dict(
+            volume_backend_name='sheepdog',
+            vendor_name='Open Source',
+            dirver_version='1.0',
+            storage_protocol='sheepdog',
+            total_capacity_gb=float(107287605248) / (1024 ** 3),
+            free_capacity_gb=float(107287605248 - 3623897354) / (1024 ** 3),
+            reserved_percentage=0,
+            QoS_support=False)
+        actual = self.driver.get_volume_stats(True)
+        self.assertDictMatch(expected, actual)
+
+    def test_update_volume_stats_error(self):
+        def fake_stats(*args):
+            raise exception.ProcessExecutionError()
+        self.stubs.Set(self.driver, '_execute', fake_stats)
+        expected = dict(
+            volume_backend_name='sheepdog',
+            vendor_name='Open Source',
+            dirver_version='1.0',
+            storage_protocol='sheepdog',
+            total_capacity_gb='unknown',
+            free_capacity_gb='unknown',
+            reserved_percentage=0,
+            QoS_support=False)
+        actual = self.driver.get_volume_stats(True)
+        self.assertDictMatch(expected, actual)
diff --git a/cinder/volume/drivers/sheepdog.py b/cinder/volume/drivers/sheepdog.py
index 9fb390482..d1916c7ad 100644
--- a/cinder/volume/drivers/sheepdog.py
+++ b/cinder/volume/drivers/sheepdog.py
@@ -16,6 +16,7 @@
 SheepDog Volume Driver.
 
 """
+import re
 
 from cinder import exception
 from cinder import flags
@@ -30,6 +31,19 @@ FLAGS = flags.FLAGS
 class SheepdogDriver(driver.VolumeDriver):
     """Executes commands relating to Sheepdog Volumes"""
 
+    def __init__(self, *args, **kwargs):
+        super(SheepdogDriver, self).__init__(*args, **kwargs)
+        self._stats = dict(
+            volume_backend_name='sheepdog',
+            vendor_name='Open Source',
+            dirver_version='1.0',
+            storage_protocol='sheepdog',
+            total_capacity_gb='unknown',
+            free_capacity_gb='unknown',
+            reserved_percentage=0,
+            QoS_support=False)
+        self.stats_pattern = re.compile(r'[\w\s%]*Total\s(\d+)\s(\d+)*')
+
     def check_for_setup_error(self):
         """Returns an error if prerequisites aren't met"""
         try:
@@ -101,3 +115,21 @@ class SheepdogDriver(driver.VolumeDriver):
 
     def terminate_connection(self, volume, connector, **kwargs):
         pass
+
+    def _update_volume_stats(self):
+        stats = {}
+        try:
+            stdout, _err = self._execute('collie', 'node', 'info', '-r')
+            m = self.stats_pattern.match(stdout)
+            total = float(m.group(1))
+            used = float(m.group(2))
+            stats['total_capacity_gb'] = total / (1024 ** 3)
+            stats['free_capacity_gb'] = (total - used) / (1024 ** 3)
+        except exception.ProcessExecutionError:
+            LOG.exception(_('error refreshing volume stats'))
+        self._stats.update(stats)
+
+    def get_volume_stats(self, refresh=False):
+        if refresh:
+            self._update_volume_stats()
+        return self._stats
-- 
2.45.2