1d1e4ccb3e
Currently we pass a reference to a global "rollback" list to create() to keep rollback functions. Other nodes don't need to know about global rollback state, and by passing by reference we're giving them the chance to mess it up for everyone else. Add a "add_rollback()" function in NodeBase for create() calls to register rollback calls within themselves. As they hit rollback points they can add a new entry. lambda v arguments is much of a muchness -- but this is similar to the standard atexit() call so with go with that pattern. A new "rollback()" call is added that the driver will invoke on each node as it works its way backwards in case of failure. On error, nodes will have rollback() called in reverse order (which then calls registered rollbacks in reverse order). A unit test is added to test rollback behaviour Change-Id: I65214e72c7ef607dd08f750a6d32a0b10fe97ac3
81 lines
2.7 KiB
Python
81 lines
2.7 KiB
Python
# 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.
|
|
|
|
# plugin test case
|
|
|
|
import logging
|
|
|
|
from diskimage_builder.block_device.plugin import NodeBase
|
|
from diskimage_builder.block_device.plugin import PluginBase
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class TestANode(NodeBase):
|
|
def __init__(self, config, state, test_rollback):
|
|
logger.debug("Create test 1")
|
|
super(TestANode, self).__init__(config['name'], state)
|
|
# might be a root node, so possibly no base
|
|
if 'base' in config:
|
|
self.base = config['base']
|
|
|
|
# put something in the state for test_b to check for
|
|
state['test_init_state'] = 'here'
|
|
|
|
# If we're doing rollback testing the config has some strings
|
|
# set for us
|
|
if test_rollback:
|
|
self.add_rollback(self.do_rollback, config['rollback_one_arg'])
|
|
self.add_rollback(self.do_rollback, config['rollback_two_arg'])
|
|
# see if we're the node who is going to fail
|
|
self.trigger_rollback = True if 'trigger_rollback' in config else False
|
|
|
|
def get_edges(self):
|
|
# may not have a base, if used as root node
|
|
to = [self.base] if hasattr(self, 'base') else []
|
|
return (to, [])
|
|
|
|
def do_rollback(self, string):
|
|
# We will check this after all rollbacks to make sure they ran
|
|
# in the right order
|
|
self.state['rollback_test'].append(string)
|
|
|
|
def create(self):
|
|
# put some fake entries into state
|
|
self.state['test_a'] = {}
|
|
self.state['test_a']['value'] = 'foo'
|
|
self.state['test_a']['value2'] = 'bar'
|
|
|
|
if self.trigger_rollback:
|
|
# The rollback test will append the strings to this as
|
|
# it unrolls, and we'll check it's value at the end
|
|
self.state['rollback_test'] = []
|
|
raise RuntimeError("Rollback triggered")
|
|
|
|
return
|
|
|
|
def umount(self):
|
|
# Umount is run in reverse. This key should exist from test_b
|
|
self.state['umount'].append('test_a')
|
|
|
|
|
|
class TestA(PluginBase):
|
|
|
|
def __init__(self, config, defaults, state):
|
|
super(TestA, self).__init__()
|
|
|
|
test_rollback = True if 'test_rollback' in defaults else False
|
|
self.node = TestANode(config, state, test_rollback)
|
|
|
|
def get_nodes(self):
|
|
return [self.node]
|