Files
python-heatclient/heatclient/common/event_utils.py
Steven Hardy 53c46f0b34 Add hook-poll function to check if a stack has pending hooks
Currently using the breakpoints/hooks functionality on large trees of
stacks is a bit inconvenient, because you may set hooks in nested stacks
so the events aren't easily visible via the top-level event interfaces.

This has been addressed via the new --nested-depth option to event-list,
but it's still hard to determine (programatically e.g from a script) if
there's pending hook which requires clearing.

So this patch introduces an initial implementation of a specialized
event-list function "hook-poll", which filters the events and displays
only those events which have pending hooks (e.g those which have yet
to be signalled to clear them).

I expect the efficiency of the implementation can be much improved in the
future if we add a propert nested_depth argument to the heat events API,
and/or add a hook API which enables easier introspection of hook status.
The CLI interface should be reasonable in the event such rework happens,
but the current (slow) implementation will work with the API interfaces
we have available now in kilo Heat.

Change-Id: I71b19202ab29f44e5c09b4ee04be4aeaea038c28
2015-05-11 11:01:08 +01:00

129 lines
5.2 KiB
Python

# Copyright 2015 Red Hat 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.
from heatclient.common import utils
import heatclient.exc as exc
from heatclient.openstack.common._i18n import _
def get_hook_events(hc, stack_id, event_args, nested_depth=0,
hook_type='pre-create'):
if hook_type == 'pre-create':
stack_action_reason = 'Stack CREATE started'
hook_event_reason = 'CREATE paused until Hook pre-create is cleared'
hook_clear_event_reason = 'Hook pre-create is cleared'
elif hook_type == 'pre-update':
stack_action_reason = 'Stack UPDATE started'
hook_event_reason = 'UPDATE paused until Hook pre-update is cleared'
hook_clear_event_reason = 'Hook pre-update is cleared'
else:
raise exc.CommandError(_('Unexpected hook type %s') % hook_type)
events = get_events(hc, stack_id=stack_id, event_args=event_args,
nested_depth=nested_depth)
# Get the most recent event associated with this action, which gives us the
# event when we moved into IN_PROGRESS for the hooks we're interested in.
stack_name = stack_id.split("/")[0]
action_start_event = [e for e in enumerate(events)
if e[1].resource_status_reason == stack_action_reason
and e[1].stack_name == stack_name][-1]
# Slice the events with the index from the enumerate
action_start_index = action_start_event[0]
events = events[action_start_index:]
# Get hook events still pending by some list filtering/comparison
# We build a map hook events per-resource, and remove any event
# for which there is a corresponding hook-clear event.
resource_event_map = {}
for e in events:
stack_resource = (e.stack_name, e.resource_name)
if e.resource_status_reason == hook_event_reason:
resource_event_map[(e.stack_name, e.resource_name)] = e
elif e.resource_status_reason == hook_clear_event_reason:
if resource_event_map.get(stack_resource):
del(resource_event_map[(e.stack_name, e.resource_name)])
return list(resource_event_map.values())
def get_events(hc, stack_id, event_args, nested_depth=0,
marker=None, limit=None):
events = _get_stack_events(hc, stack_id, event_args)
if nested_depth > 0:
events.extend(_get_nested_events(hc, nested_depth,
stack_id, event_args))
# Because there have been multiple stacks events mangled into
# one list, we need to sort before passing to print_list
# Note we can't use the prettytable sortby_index here, because
# the "start" option doesn't allow post-sort slicing, which
# will be needed to make "--marker" work for nested_depth lists
events.sort(key=lambda x: x.event_time)
# Slice the list if marker is specified
if marker:
marker_index = [e.id for e in events].index(marker)
events = events[marker_index:]
# Slice the list if limit is specified
if limit:
limit_index = min(int(limit), len(events))
events = events[:limit_index]
return events
def _get_nested_ids(hc, stack_id):
nested_ids = []
try:
resources = hc.resources.list(stack_id=stack_id)
except exc.HTTPNotFound:
raise exc.CommandError(_('Stack not found: %s') % stack_id)
for r in resources:
nested_id = utils.resource_nested_identifier(r)
if nested_id:
nested_ids.append(nested_id)
return nested_ids
def _get_nested_events(hc, nested_depth, stack_id, event_args):
# FIXME(shardy): this is very inefficient, we should add nested_depth to
# the event_list API in a future heat version, but this will be required
# until kilo heat is EOL.
nested_ids = _get_nested_ids(hc, stack_id)
nested_events = []
for n_id in nested_ids:
stack_events = _get_stack_events(hc, n_id, event_args)
if stack_events:
nested_events.extend(stack_events)
if nested_depth > 1:
next_depth = nested_depth - 1
nested_events.extend(_get_nested_events(
hc, next_depth, n_id, event_args))
return nested_events
def _get_stack_events(hc, stack_id, event_args):
event_args['stack_id'] = stack_id
try:
events = hc.events.list(**event_args)
except exc.HTTPNotFound as ex:
# it could be the stack or resource that is not found
# just use the message that the server sent us.
raise exc.CommandError(str(ex))
else:
# Show which stack the event comes from (for nested events)
for e in events:
e.stack_name = stack_id.split("/")[0]
return events