Function to create config-drive partition

Add function to create partition for config-drive to util/disk.py
module. This is required to switch from 'cobbler' to 'image'
provision method.

Change-Id: Ia52195a2e25e4e459c8947eb2dfaea97195dbe7f
Related-bug: 1575054

octane/handlers/upgrade/compute.py

@@ -30,7 +30,7 @@ class ComputeUpgrade(upgrade.UpgradeHandler):
     def prepare(self):
         env = self.node.env
         if env_util.incompatible_provision_method(env):
-            self.create_configdrive_partition()
+            disk.create_configdrive_partition()
             disk.update_node_partition_info(self.node.id)
         if not self.live_migration:
             self.preserve_partition()
@@ -103,15 +103,6 @@ class ComputeUpgrade(upgrade.UpgradeHandler):
                'xargs -I% nova stop %']
         ssh.call(["sh", "-c", ' '.join(cmd)], stdout=ssh.PIPE, node=controller)
 
-    def create_configdrive_partition(self):
-        disks = disk.get_node_disks(self.node)
-        if not disks:
-            raise Exception("No disks info was found "
-                            "for node {0}".format(self.node["id"]))
-        # it was agreed that 10MB is enough for config drive partition
-        size = 10
-        disk.create_partition(disks[0]['name'], size, self.node)
-
     def backup_iscsi_initiator_info(self):
         if not plugin.is_enabled(self.env, 'emc_vnx'):
             return

octane/magic_consts.py

@@ -72,3 +72,5 @@ UPGRADE_NODE_PATCHES = [
 ]
 
 BOOTSTRAP_UNSUPPORTED_IMAGES = ["centos"]
+# NOTE(ogelbukh): it was agreed that 10MB is enough for config drive partition
+CONFIGDRIVE_PART_SIZE = 10

octane/tests/test_util_disk.py

@@ -13,6 +13,7 @@
 import os
 import pytest
 
+from octane import magic_consts
 from octane.util import disk as disk_util
 
 
@@ -46,3 +47,33 @@ def test_update_partition_info(mocker, node):
     ]
     disk_util.update_node_partition_info(test_node_id)
     mock_run_in_container.assert_called_once_with(container, expected_command)
+
+
+NODE_DISKS_ATTRIBUTE = [
+    {
+        'id': '1',
+        'name': 'disk1',
+    }, {
+        'id': '2',
+        'name': 'disk2',
+    }
+]
+
+
+@pytest.mark.parametrize("disk_attrs", [
+    NODE_DISKS_ATTRIBUTE,
+    None,
+])
+def test_create_configdrive_partition(mocker, node, disk_attrs):
+    name = 'disk1'
+    node.mock_add_spec(['get_attribute'])
+    node.data = {"id": "1"}
+    node.get_attribute.return_value = disk_attrs
+    mock_create_part = mocker.patch("octane.util.disk.create_partition")
+    if disk_attrs:
+        disk_util.create_configdrive_partition(node)
+        mock_create_part.assert_called_once_with(
+            name, magic_consts.CONFIGDRIVE_PART_SIZE, node)
+    else:
+        with pytest.raises(disk_util.NoDisksInfoError):
+            disk_util.create_configdrive_partition(node)

octane/util/disk.py

@@ -11,10 +11,18 @@
 # under the License.
 import os.path
 
+from octane import magic_consts
 from octane.util import docker
 from octane.util import ssh
 
 
+class NoDisksInfoError(Exception):
+    message = "No disks info was found for node {0}"
+
+    def __init__(self, node_id):
+        super(NoDisksInfoError, self).__init__(self.message.format(node_id))
+
+
 def get_node_disks(node):
     return node.get_attribute('disks')
 
@@ -42,3 +50,12 @@ def update_node_partition_info(node_id):
     fname = 'update_node_partition_info.py'
     command = ['python', os.path.join('/tmp', fname), str(node_id)]
     docker.run_in_container('nailgun', command)
+
+
+def create_configdrive_partition(node):
+    disks = get_node_disks(node)
+    if not disks:
+        raise NoDisksInfoError(node.data['id'])
+    create_partition(disks[0]['name'],
+                     magic_consts.CONFIGDRIVE_PART_SIZE,
+                     node)