Add creation date column to snapshot list

* Added wrapper around snapshots returned by libvirt to make whole code
  more pythonic
* Snapshots are sorted by creation date by default
* Added lxml as runtime dependency
* Added tabulate as runtime dependency and used to print snapshot
  tabular data

DocImpact
Closes-Bug: #1463361

Change-Id: Ia2c2fab4ac763865ab3f837c63a87101e567d6e8

bin/dos.py

@@ -17,6 +17,6 @@ from os import environ
 
 if __name__ == "__main__":
     environ.setdefault("DJANGO_SETTINGS_MODULE", "devops.settings")
-    from devops.shell import Shell
+    from devops.shell import main
 
-    Shell().execute()
+    main()

devops/driver/libvirt/libvirt_driver.py

@@ -12,12 +12,14 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import ipaddr
-import libvirt
-
+import datetime
 from time import sleep
 import xml.etree.ElementTree as ET
 
+import ipaddr
+import libvirt
+from lxml import etree
+
 from devops.driver.libvirt.libvirt_xml_builder import LibvirtXMLBuilder
 from devops.helpers.helpers import _get_file_size
 from devops.helpers.retry import retry
@@ -27,6 +29,31 @@ from devops import logger
 from django.conf import settings
 
 
+class Snapshot(object):
+
+    def __init__(self, snapshot):
+        self._snapshot = snapshot
+        self._xml = snapshot.getXMLDesc(0)
+        self._repr = ""
+
+    @property
+    def created(self):
+        xml_tree = etree.fromstring(self._xml)
+
+        timestamp = xml_tree.xpath('/domainsnapshot/creationTime/text()')[0]
+        return datetime.datetime.utcfromtimestamp(float(timestamp))
+
+    @property
+    def name(self):
+        return self._snapshot.getName()
+
+    def __repr__(self):
+        if not self._repr:
+            self._repr = "<{0} {1}/{2}>".format(
+                self.__class__.__name__, self.name, self.created)
+        return self._repr
+
+
 class DevopsDriver(object):
     def __init__(self,
                  connection_string="qemu:///system",
@@ -347,7 +374,9 @@ class DevopsDriver(object):
         :rtype : List
             :type node: Node
         """
-        return self.conn.lookupByUUIDString(node.uuid).snapshotListNames(0)
+
+        snapshots = self.conn.lookupByUUIDString(node.uuid).listAllSnapshots(0)
+        return [Snapshot(snap) for snap in snapshots]
 
     @retry()
     def node_create_snapshot(self, node, name=None, description=None):

devops/models/node.py

@@ -152,6 +152,7 @@ class Node(DriverModel):
                   ' name {1}'.format(self.name, name))
 
     def get_snapshots(self):
+        """Return full snapshots objects"""
         return self.driver.node_get_snapshots(node=self)
 
     def erase_snapshot(self, name):

devops/shell.py

@@ -13,10 +13,12 @@
 #    under the License.
 
 import argparse
+import collections
 import os
 import sys
 
 import ipaddr
+import tabulate
 
 import devops
 from devops.helpers.helpers import _get_file_size
@@ -28,7 +30,8 @@ from devops import settings
 
 
 class Shell(object):
-    def __init__(self):
+    def __init__(self, args):
+        self.args = args
         self.params = self.get_params()
         if (getattr(self.params, 'name', None) and
                 getattr(self.params, 'command', None) != 'create'):
@@ -37,6 +40,10 @@ class Shell(object):
     def execute(self):
         self.commands.get(self.params.command)(self)
 
+    def print_table(self, headers, columns):
+        print(tabulate.tabulate(columns, headers=headers,
+                                tablefmt="simple"))
+
     def do_list(self):
         env_list = Environment.list().values('name', 'created')
         for env in env_list:
@@ -89,26 +96,34 @@ class Shell(object):
         Environment.synchronize_all()
 
     def do_snapshot_list(self):
-        snap_nodes = {}
-        max_len = 0
-        for node in self.env.get_nodes():
-            snaps = sorted(node.get_snapshots())
-            for snap in snaps:
-                if len(snap) > max_len:
-                    max_len = len(snap)
-                if snap in snap_nodes:
-                    snap_nodes[snap].append(node.name)
-                else:
-                    snap_nodes[snap] = [node.name, ]
+        snapshots = collections.OrderedDict()
 
-        print("%*s     %50s" % (max_len, "SNAPSHOT", "NODES-NAME"))
-        for snap in snap_nodes:
-            print("%*s     %50s" % (max_len, snap,
-                                    ', '.join(snap_nodes[snap])))
+        Snap = collections.namedtuple('Snap', ['info', 'nodes'])
+
+        for node in self.env.get_nodes():
+            for snap in node.get_snapshots():
+                if snap.name in snapshots:
+                    snapshots[snap.name].nodes.append(node.name)
+                else:
+                    snapshots[snap.name] = Snap(snap, [node.name, ])
+
+        snapshots = sorted(snapshots.values(), key=lambda x: x.info.created)
+
+        headers = ('SNAPSHOT', 'CREATED', 'NODES-NAMES')
+        columns = []
+        for info, nodes in snapshots:
+            nodes.sort()
+            columns.append((
+                info.name,
+                info.created.strftime('%Y-%m-%d %H:%M:%S'),
+                ', '.join(nodes),
+            ))
+
+        self.print_table(columns=columns, headers=headers)
 
     def do_snapshot_delete(self):
         for node in self.env.get_nodes():
-            snaps = sorted(node.get_snapshots())
+            snaps = map(lambda x: x.name, node.get_snapshots())
             if self.params.snapshot_name in snaps:
                 node.erase_snapshot(name=self.params.snapshot_name)
 
@@ -472,6 +487,12 @@ class Shell(object):
                               help="Reset (restart) node in environment",
                               description="Reset a separate node in "
                                           "environment")
-        if len(sys.argv) == 1:
-            sys.argv.append("-h")
-        return parser.parse_args()
+        if len(self.args) == 0:
+            self.args = ['-h']
+        return parser.parse_args(self.args)
+
+
+def main(args=None):
+    if args is None:
+        args = sys.argv[1:]
+    Shell(args).execute()

devops/tests/test_shell.py

@@ -0,0 +1,62 @@
+# -*- coding: utf-8 -*-
+
+#    Copyright 2015 Mirantis, Inc.
+#
+#    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.
+
+import datetime
+import unittest
+
+import mock
+
+from devops import models
+from devops import shell
+
+
+class BaseShellTestCase(unittest.TestCase):
+
+    def execute(self, *args):
+        return shell.main(args)
+
+
+class TestSnaphotList(BaseShellTestCase):
+
+    @mock.patch.object(shell.Shell, 'print_table')
+    @mock.patch.object(models.Environment, 'get')
+    def test_snapshot_list_order(self, mock_get_env, mock_print):
+        snaps = []
+        base_date = datetime.datetime(2015, 12, 1)
+        for i in range(4):
+            snap = mock.Mock()
+            snap.name = "snap_{0}".format(i)
+            snap.created = base_date - datetime.timedelta(days=i)
+            snaps.append(snap)
+
+        node = mock.Mock()
+        node.name = "node"
+        node.get_snapshots.return_value = snaps
+
+        env = mock_get_env.return_value
+        env.get_nodes.return_value = [node, node]
+
+        self.execute('snapshot-list', 'some-env')
+
+        mock_print.assert_called(
+            columns=[
+                ('snap_3', '2015-11-28 00:00:00', 'node, node'),
+                ('snap_2', '2015-11-29 00:00:00', 'node, node'),
+                ('snap_1', '2015-11-30 00:00:00', 'node, node'),
+                ('snap_0', '2015-12-01 00:00:00', 'node, node')
+            ],
+            headers=('SNAPSHOT', 'CREATED', 'NODES-NAMES')
+        )

setup.py

@@ -42,5 +42,7 @@ setup(
         'south',
         'PyYAML',
         'libvirt-python',
+        'lxml',
+        'tabulate',
     ]
 )