1 files changed, 103 insertions, 0 deletions
diff --git a/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/storage/linux/lvm.py b/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/storage/linux/lvm.py
new file mode 100644
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--- /dev/null
+++ b/charms/trusty/ceilometer-agent/hooks/charmhelpers/contrib/storage/linux/lvm.py
@@ -0,0 +1,103 @@
+# Copyright 2014-2015 Canonical Limited.
+#
+# 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 subprocess import (
+    CalledProcessError,
+    check_call,
+    check_output,
+    Popen,
+    PIPE,
+)
+
+
+##################################################
+# LVM helpers.
+##################################################
+def deactivate_lvm_volume_group(block_device):
+    '''
+    Deactivate any volume gruop associated with an LVM physical volume.
+
+    :param block_device: str: Full path to LVM physical volume
+    '''
+    vg = list_lvm_volume_group(block_device)
+    if vg:
+        cmd = ['vgchange', '-an', vg]
+        check_call(cmd)
+
+
+def is_lvm_physical_volume(block_device):
+    '''
+    Determine whether a block device is initialized as an LVM PV.
+
+    :param block_device: str: Full path of block device to inspect.
+
+    :returns: boolean: True if block device is a PV, False if not.
+    '''
+    try:
+        check_output(['pvdisplay', block_device])
+        return True
+    except CalledProcessError:
+        return False
+
+
+def remove_lvm_physical_volume(block_device):
+    '''
+    Remove LVM PV signatures from a given block device.
+
+    :param block_device: str: Full path of block device to scrub.
+    '''
+    p = Popen(['pvremove', '-ff', block_device],
+              stdin=PIPE)
+    p.communicate(input='y\n')
+
+
+def list_lvm_volume_group(block_device):
+    '''
+    List LVM volume group associated with a given block device.
+
+    Assumes block device is a valid LVM PV.
+
+    :param block_device: str: Full path of block device to inspect.
+
+    :returns: str: Name of volume group associated with block device or None
+    '''
+    vg = None
+    pvd = check_output(['pvdisplay', block_device]).splitlines()
+    for l in pvd:
+        l = l.decode('UTF-8')
+        if l.strip().startswith('VG Name'):
+            vg = ' '.join(l.strip().split()[2:])
+    return vg
+
+
+def create_lvm_physical_volume(block_device):
+    '''
+    Initialize a block device as an LVM physical volume.
+
+    :param block_device: str: Full path of block device to initialize.
+
+    '''
+    check_call(['pvcreate', block_device])
+
+
+def create_lvm_volume_group(volume_group, block_device):
+    '''
+    Create an LVM volume group backed by a given block device.
+
+    Assumes block device has already been initialized as an LVM PV.
+
+    :param volume_group: str: Name of volume group to create.
+    :block_device: str: Full path of PV-initialized block device.
+    '''
+    check_call(['vgcreate', volume_group, block_device])