374 lines
14 KiB
Python
374 lines
14 KiB
Python
# Copyright 2019, David Wilson
|
|
#
|
|
# Redistribution and use in source and binary forms, with or without
|
|
# modification, are permitted provided that the following conditions are met:
|
|
#
|
|
# 1. Redistributions of source code must retain the above copyright notice,
|
|
# this list of conditions and the following disclaimer.
|
|
#
|
|
# 2. Redistributions in binary form must reproduce the above copyright notice,
|
|
# this list of conditions and the following disclaimer in the documentation
|
|
# and/or other materials provided with the distribution.
|
|
#
|
|
# 3. Neither the name of the copyright holder nor the names of its contributors
|
|
# may be used to endorse or promote products derived from this software without
|
|
# specific prior written permission.
|
|
#
|
|
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
|
|
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
# POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
from __future__ import absolute_import
|
|
import distutils.version
|
|
import os
|
|
import signal
|
|
import threading
|
|
|
|
try:
|
|
import setproctitle
|
|
except ImportError:
|
|
setproctitle = None
|
|
|
|
import mitogen.core
|
|
import ansible_mitogen.affinity
|
|
import ansible_mitogen.loaders
|
|
import ansible_mitogen.mixins
|
|
import ansible_mitogen.process
|
|
|
|
import ansible
|
|
import ansible.executor.process.worker
|
|
|
|
try:
|
|
# 2.8+ has a standardized "unset" object.
|
|
from ansible.utils.sentinel import Sentinel
|
|
except ImportError:
|
|
Sentinel = None
|
|
|
|
|
|
ANSIBLE_VERSION_MIN = (2, 3)
|
|
ANSIBLE_VERSION_MAX = (2, 9)
|
|
NEW_VERSION_MSG = (
|
|
"Your Ansible version (%s) is too recent. The most recent version\n"
|
|
"supported by Mitogen for Ansible is %s.x. Please check the Mitogen\n"
|
|
"release notes to see if a new version is available, otherwise\n"
|
|
"subscribe to the corresponding GitHub issue to be notified when\n"
|
|
"support becomes available.\n"
|
|
"\n"
|
|
" https://mitogen.rtfd.io/en/latest/changelog.html\n"
|
|
" https://github.com/dw/mitogen/issues/\n"
|
|
)
|
|
OLD_VERSION_MSG = (
|
|
"Your version of Ansible (%s) is too old. The oldest version supported by "
|
|
"Mitogen for Ansible is %s."
|
|
)
|
|
|
|
|
|
def _assert_supported_release():
|
|
"""
|
|
Throw AnsibleError with a descriptive message in case of being loaded into
|
|
an unsupported Ansible release.
|
|
"""
|
|
v = ansible.__version__
|
|
if not isinstance(v, tuple):
|
|
v = tuple(distutils.version.LooseVersion(v).version)
|
|
|
|
if v[:2] < ANSIBLE_VERSION_MIN:
|
|
raise ansible.errors.AnsibleError(
|
|
OLD_VERSION_MSG % (v, ANSIBLE_VERSION_MIN)
|
|
)
|
|
|
|
if v[:2] > ANSIBLE_VERSION_MAX:
|
|
raise ansible.errors.AnsibleError(
|
|
NEW_VERSION_MSG % (ansible.__version__, ANSIBLE_VERSION_MAX)
|
|
)
|
|
|
|
|
|
def _patch_awx_callback():
|
|
"""
|
|
issue #400: AWX loads a display callback that suffers from thread-safety
|
|
issues. Detect the presence of older AWX versions and patch the bug.
|
|
"""
|
|
# AWX uses sitecustomize.py to force-load this package. If it exists, we're
|
|
# running under AWX.
|
|
try:
|
|
from awx_display_callback.events import EventContext
|
|
from awx_display_callback.events import event_context
|
|
except ImportError:
|
|
return
|
|
|
|
if hasattr(EventContext(), '_local'):
|
|
# Patched version.
|
|
return
|
|
|
|
def patch_add_local(self, **kwargs):
|
|
tls = vars(self._local)
|
|
ctx = tls.setdefault('_ctx', {})
|
|
ctx.update(kwargs)
|
|
|
|
EventContext._local = threading.local()
|
|
EventContext.add_local = patch_add_local
|
|
|
|
_patch_awx_callback()
|
|
|
|
|
|
def wrap_action_loader__get(name, *args, **kwargs):
|
|
"""
|
|
While the mitogen strategy is active, trap action_loader.get() calls,
|
|
augmenting any fetched class with ActionModuleMixin, which replaces various
|
|
helper methods inherited from ActionBase with implementations that avoid
|
|
the use of shell fragments wherever possible.
|
|
|
|
This is used instead of static subclassing as it generalizes to third party
|
|
action plugins outside the Ansible tree.
|
|
"""
|
|
get_kwargs = {'class_only': True}
|
|
if name in ('fetch',):
|
|
name = 'mitogen_' + name
|
|
if ansible.__version__ >= '2.8':
|
|
get_kwargs['collection_list'] = kwargs.pop('collection_list', None)
|
|
|
|
klass = ansible_mitogen.loaders.action_loader__get(name, **get_kwargs)
|
|
if klass:
|
|
bases = (ansible_mitogen.mixins.ActionModuleMixin, klass)
|
|
adorned_klass = type(str(name), bases, {})
|
|
if kwargs.get('class_only'):
|
|
return adorned_klass
|
|
return adorned_klass(*args, **kwargs)
|
|
|
|
|
|
REDIRECTED_CONNECTION_PLUGINS = (
|
|
'buildah',
|
|
'docker',
|
|
'kubectl',
|
|
'jail',
|
|
'local',
|
|
'lxc',
|
|
'lxd',
|
|
'machinectl',
|
|
'setns',
|
|
'ssh',
|
|
)
|
|
|
|
|
|
def wrap_connection_loader__get(name, *args, **kwargs):
|
|
"""
|
|
While a Mitogen strategy is active, rewrite connection_loader.get() calls
|
|
for some transports into requests for a compatible Mitogen transport.
|
|
"""
|
|
if name in REDIRECTED_CONNECTION_PLUGINS:
|
|
name = 'mitogen_' + name
|
|
|
|
return ansible_mitogen.loaders.connection_loader__get(name, *args, **kwargs)
|
|
|
|
|
|
def wrap_worker__run(self):
|
|
"""
|
|
While a Mitogen strategy is active, trap WorkerProcess.run() calls and use
|
|
the opportunity to set the worker's name in the process list and log
|
|
output, activate profiling if requested, and bind the worker to a specific
|
|
CPU.
|
|
"""
|
|
if setproctitle:
|
|
setproctitle.setproctitle('worker:%s task:%s' % (
|
|
self._host.name,
|
|
self._task.action,
|
|
))
|
|
|
|
# Ignore parent's attempts to murder us when we still need to write
|
|
# profiling output.
|
|
if mitogen.core._profile_hook.__name__ != '_profile_hook':
|
|
signal.signal(signal.SIGTERM, signal.SIG_IGN)
|
|
|
|
ansible_mitogen.logging.set_process_name('task')
|
|
ansible_mitogen.affinity.policy.assign_worker()
|
|
return mitogen.core._profile_hook('WorkerProcess',
|
|
lambda: worker__run(self)
|
|
)
|
|
|
|
|
|
class AnsibleWrappers(object):
|
|
"""
|
|
Manage add/removal of various Ansible runtime hooks.
|
|
"""
|
|
def _add_plugin_paths(self):
|
|
"""
|
|
Add the Mitogen plug-in directories to the ModuleLoader path, avoiding
|
|
the need for manual configuration.
|
|
"""
|
|
base_dir = os.path.join(os.path.dirname(__file__), 'plugins')
|
|
ansible_mitogen.loaders.connection_loader.add_directory(
|
|
os.path.join(base_dir, 'connection')
|
|
)
|
|
ansible_mitogen.loaders.action_loader.add_directory(
|
|
os.path.join(base_dir, 'action')
|
|
)
|
|
|
|
def _install_wrappers(self):
|
|
"""
|
|
Install our PluginLoader monkey patches and update global variables
|
|
with references to the real functions.
|
|
"""
|
|
ansible_mitogen.loaders.action_loader.get = wrap_action_loader__get
|
|
ansible_mitogen.loaders.connection_loader.get = wrap_connection_loader__get
|
|
|
|
global worker__run
|
|
worker__run = ansible.executor.process.worker.WorkerProcess.run
|
|
ansible.executor.process.worker.WorkerProcess.run = wrap_worker__run
|
|
|
|
def _remove_wrappers(self):
|
|
"""
|
|
Uninstall the PluginLoader monkey patches.
|
|
"""
|
|
ansible_mitogen.loaders.action_loader.get = (
|
|
ansible_mitogen.loaders.action_loader__get
|
|
)
|
|
ansible_mitogen.loaders.connection_loader.get = (
|
|
ansible_mitogen.loaders.connection_loader__get
|
|
)
|
|
ansible.executor.process.worker.WorkerProcess.run = worker__run
|
|
|
|
def install(self):
|
|
self._add_plugin_paths()
|
|
self._install_wrappers()
|
|
|
|
def remove(self):
|
|
self._remove_wrappers()
|
|
|
|
|
|
class StrategyMixin(object):
|
|
"""
|
|
This mix-in enhances any built-in strategy by arranging for an appropriate
|
|
WorkerModel instance to be constructed as necessary, or for the existing
|
|
one to be reused.
|
|
|
|
The WorkerModel in turn arranges for a connection multiplexer to be started
|
|
somewhere (by default in an external process), and for WorkerProcesses to
|
|
grow support for using those top-level services to communicate with remote
|
|
hosts.
|
|
|
|
Mitogen:
|
|
|
|
A private Broker IO multiplexer thread is created to dispatch IO
|
|
between the local Router and any connected streams, including streams
|
|
connected to Ansible WorkerProcesses, and SSH commands implementing
|
|
connections to remote machines.
|
|
|
|
A Router is created that implements message dispatch to any locally
|
|
registered handlers, and message routing for remote streams. Router is
|
|
the junction point through which WorkerProceses and remote SSH contexts
|
|
can communicate.
|
|
|
|
Router additionally adds message handlers for a variety of base
|
|
services, review the Standard Handles section of the How It Works guide
|
|
in the documentation.
|
|
|
|
A ContextService is installed as a message handler in the connection
|
|
mutliplexer subprocess and run on a private thread. It is responsible
|
|
for accepting requests to establish new SSH connections from worker
|
|
processes, and ensuring precisely one connection exists and is reused
|
|
for subsequent playbook steps. The service presently runs in a single
|
|
thread, so to begin with, new SSH connections are serialized.
|
|
|
|
Finally a mitogen.unix listener is created through which WorkerProcess
|
|
can establish a connection back into the connection multiplexer, in
|
|
order to avail of ContextService. A UNIX listener socket is necessary
|
|
as there is no more sane mechanism to arrange for IPC between the
|
|
Router in the connection multiplexer, and the corresponding Router in
|
|
the worker process.
|
|
|
|
Ansible:
|
|
|
|
PluginLoader monkey patches are installed to catch attempts to create
|
|
connection and action plug-ins.
|
|
|
|
For connection plug-ins, if the desired method is "local" or "ssh", it
|
|
is redirected to one of the "mitogen_*" connection plug-ins. That
|
|
plug-in implements communication via a UNIX socket connection to the
|
|
connection multiplexer process, and uses ContextService running there
|
|
to establish a persistent connection to the target.
|
|
|
|
For action plug-ins, the original class is looked up as usual, but a
|
|
new subclass is created dynamically in order to mix-in
|
|
ansible_mitogen.target.ActionModuleMixin, which overrides many of the
|
|
methods usually inherited from ActionBase in order to replace them with
|
|
pure-Python equivalents that avoid the use of shell.
|
|
|
|
In particular, _execute_module() is overridden with an implementation
|
|
that uses ansible_mitogen.target.run_module() executed in the target
|
|
Context. run_module() implements module execution by importing the
|
|
module as if it were a normal Python module, and capturing its output
|
|
in the remote process. Since the Mitogen module loader is active in the
|
|
remote process, all the heavy lifting of transferring the action module
|
|
and its dependencies are automatically handled by Mitogen.
|
|
"""
|
|
|
|
def _queue_task(self, host, task, task_vars, play_context):
|
|
"""
|
|
Many PluginLoader caches are defective as they are only populated in
|
|
the ephemeral WorkerProcess. Touch each plug-in path before forking to
|
|
ensure all workers receive a hot cache.
|
|
"""
|
|
ansible_mitogen.loaders.module_loader.find_plugin(
|
|
name=task.action,
|
|
mod_type='',
|
|
)
|
|
ansible_mitogen.loaders.action_loader.get(
|
|
name=task.action,
|
|
class_only=True,
|
|
)
|
|
if play_context.connection is not Sentinel:
|
|
# 2.8 appears to defer computing this until inside the worker.
|
|
# TODO: figure out where it has moved.
|
|
ansible_mitogen.loaders.connection_loader.get(
|
|
name=play_context.connection,
|
|
class_only=True,
|
|
)
|
|
|
|
return super(StrategyMixin, self)._queue_task(
|
|
host=host,
|
|
task=task,
|
|
task_vars=task_vars,
|
|
play_context=play_context,
|
|
)
|
|
|
|
def _get_worker_model(self):
|
|
"""
|
|
In classic mode a single :class:`WorkerModel` exists, which manages
|
|
references and configuration of the associated connection multiplexer
|
|
process.
|
|
"""
|
|
return ansible_mitogen.process.get_classic_worker_model()
|
|
|
|
def run(self, iterator, play_context, result=0):
|
|
"""
|
|
Wrap :meth:`run` to ensure requisite infrastructure and modifications
|
|
are configured for the duration of the call.
|
|
"""
|
|
_assert_supported_release()
|
|
wrappers = AnsibleWrappers()
|
|
self._worker_model = self._get_worker_model()
|
|
ansible_mitogen.process.set_worker_model(self._worker_model)
|
|
try:
|
|
self._worker_model.on_strategy_start()
|
|
try:
|
|
wrappers.install()
|
|
try:
|
|
run = super(StrategyMixin, self).run
|
|
return mitogen.core._profile_hook('Strategy',
|
|
lambda: run(iterator, play_context)
|
|
)
|
|
finally:
|
|
wrappers.remove()
|
|
finally:
|
|
self._worker_model.on_strategy_complete()
|
|
finally:
|
|
ansible_mitogen.process.set_worker_model(None)
|