# Copyright 2015 Rackspace, 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 collections
from oslo_log import log
from ironic_python_agent import errors
from ironic_python_agent.extensions import base
from ironic_python_agent import hardware
LOG = log.getLogger()
[docs]class CleanExtension(base.BaseAgentExtension):
@base.sync_command('get_clean_steps')
[docs] def get_clean_steps(self, node, ports):
"""Get the list of clean steps supported for the node and ports
:param node: A dict representation of a node
:param ports: A dict representation of ports attached to node
:returns: A list of clean steps with keys step, priority, and
reboot_requested
"""
LOG.debug('Getting clean steps, called with node: %(node)s, '
'ports: %(ports)s', {'node': node, 'ports': ports})
hardware.cache_node(node)
# Results should be a dict, not a list
candidate_steps = hardware.dispatch_to_all_managers('get_clean_steps',
node, ports)
LOG.debug('Clean steps before deduplication: %s', candidate_steps)
clean_steps = _deduplicate_steps(candidate_steps)
LOG.debug('Returning clean steps: %s', clean_steps)
return {
'clean_steps': clean_steps,
'hardware_manager_version': _get_current_clean_version()
}
@base.async_command('execute_clean_step')
[docs] def execute_clean_step(self, step, node, ports, clean_version=None,
**kwargs):
"""Execute a clean step.
:param step: A clean step with 'step', 'priority' and 'interface' keys
:param node: A dict representation of a node
:param ports: A dict representation of ports attached to node
:param clean_version: The clean version as returned by
_get_current_clean_version() at the beginning
of cleaning/zapping
:returns: a CommandResult object with command_result set to whatever
the step returns.
"""
# Ensure the agent is still the same version, or raise an exception
LOG.debug('Executing clean step %s', step)
hardware.cache_node(node)
_check_clean_version(clean_version)
if 'step' not in step:
msg = 'Malformed clean_step, no "step" key: %s' % step
LOG.error(msg)
raise ValueError(msg)
try:
result = hardware.dispatch_to_managers(step['step'], node, ports)
except Exception as e:
msg = ('Error performing clean_step %(step)s: %(err)s' %
{'step': step['step'], 'err': e})
LOG.exception(msg)
raise errors.CleaningError(msg)
LOG.info('Clean step completed: %(step)s, result: %(result)s',
{'step': step, 'result': result})
# Cast result tuples (like output of utils.execute) as lists, or
# WSME throws errors
if isinstance(result, tuple):
result = list(result)
# Return the step that was executed so we can dispatch
# to the appropriate Ironic interface
return {
'clean_result': result,
'clean_step': step
}
def _deduplicate_steps(candidate_steps):
"""Remove duplicated clean steps
Deduplicates clean steps returned from HardwareManagers to prevent
running a given step more than once. Other than individual step
priority, it doesn't actually impact the cleaning run which specific
steps are kept and what HardwareManager they are associated with.
However, in order to make testing easier, this method returns
deterministic results.
Uses the following filtering logic to decide which step "wins":
- Keep the step that belongs to HardwareManager with highest
HardwareSupport (larger int) value.
- If equal support level, keep the step with the higher defined priority
(larger int).
- If equal support level and priority, keep the step associated with the
HardwareManager whose name comes earlier in the alphabet.
:param candidate_steps: A dict containing all possible clean steps from
all managers, key=manager, value=list of clean steps
:returns: A deduplicated dictionary of {hardware_manager:
[clean-steps]}
"""
support = hardware.dispatch_to_all_managers(
'evaluate_hardware_support')
steps = collections.defaultdict(list)
deduped_steps = collections.defaultdict(list)
for manager, manager_steps in candidate_steps.items():
# We cannot deduplicate steps with unknown hardware support
if manager not in support:
LOG.warning('Unknown hardware support for %(manager)s, '
'dropping clean steps: %(steps)s',
{'manager': manager, 'steps': manager_steps})
continue
for step in manager_steps:
# build a new dict of steps that's easier to filter
step['hwm'] = {'name': manager,
'support': support[manager]}
steps[step['step']].append(step)
for step_name, step_list in steps.items():
# determine the max support level among candidate steps
max_support = max([x['hwm']['support'] for x in step_list])
# filter out any steps that are not at the max support for this step
max_support_steps = [x for x in step_list
if x['hwm']['support'] == max_support]
# determine the max priority among remaining steps
max_priority = max([x['priority'] for x in max_support_steps])
# filter out any steps that are not at the max priority for this step
max_priority_steps = [x for x in max_support_steps
if x['priority'] == max_priority]
# if there are still multiple steps, sort by hwm name and take
# the first result
winning_step = sorted(max_priority_steps,
key=lambda x: x['hwm']['name'])[0]
# Remove extra metadata we added to the step for filtering
manager = winning_step.pop('hwm')['name']
# Add winning step to deduped_steps
deduped_steps[manager].append(winning_step)
return deduped_steps
def _check_clean_version(clean_version=None):
"""Ensure the clean version hasn't changed.
:param clean_version: Hardware manager versions used during this
cleaning cycle.
:raises: errors.CleanVersionMismatch if any hardware manager version on
the currently running agent doesn't match the one stored in
clean_version.
:returns: None
"""
# If the version is None, assume this is the first run
if clean_version is None:
return
agent_version = _get_current_clean_version()
if clean_version != agent_version:
LOG.warning('Mismatched clean versions. Agent version: %(agent), '
'node version: %(node)', {'agent': agent_version,
'node': clean_version})
raise errors.CleanVersionMismatch(agent_version=agent_version,
node_version=clean_version)
def _get_current_clean_version():
"""Fetches versions from all hardware managers.
:returns: Dict in the format {name: version} containing one entry for
every hardware manager.
"""
return {version.get('name'): version.get('version')
for version in hardware.dispatch_to_all_managers(
'get_version').values()}