# (c) 2012-2014, Michael DeHaan <michael.dehaan@gmail.com>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
# Make coding more python3-ish
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
from ansible.compat.six.moves import queue
from ansible.compat.six import iteritems, text_type
from ansible.vars import strip_internal_keys
import multiprocessing
import time
import traceback
# TODO: not needed if we use the cryptography library with its default RNG
# engine
HAS_ATFORK=True
try:
from Crypto.Random import atfork
except ImportError:
HAS_ATFORK=False
from ansible.utils.debug import debug
__all__ = ['ResultProcess']
class ResultProcess(multiprocessing.Process):
'''
The result worker thread, which reads results from the results
queue and fires off callbacks/etc. as necessary.
'''
def __init__(self, final_q, workers):
# takes a task queue manager as the sole param:
self._final_q = final_q
self._workers = workers
self._cur_worker = 0
self._terminated = False
super(ResultProcess, self).__init__()
def _send_result(self, result):
debug(u"sending result: %s" % ([text_type(x) for x in result],))
self._final_q.put(result, block=False)
debug("done sending result")
def _read_worker_result(self):
result = None
starting_point = self._cur_worker
while True:
(worker_prc, main_q, rslt_q) = self._workers[self._cur_worker]
self._cur_worker += 1
if self._cur_worker >= len(self._workers):
self._cur_worker = 0
try:
if not rslt_q.empty():
debug("worker %d has data to read" % self._cur_worker)
result = rslt_q.get(block=False)
debug("got a result from worker %d: %s" % (self._cur_worker, result))
break
except queue.Empty:
pass
if self._cur_worker == starting_point:
break
return result
def terminate(self):
self._terminated = True
super(ResultProcess, self).terminate()
def run(self):
'''
The main thread execution, which reads from the results queue
indefinitely and sends callbacks/etc. when results are received.
'''
if HAS_ATFORK:
atfork()
while True:
try:
result = self._read_worker_result()
if result is None:
time.sleep(0.01)
continue
clean_copy = strip_internal_keys(result._result)
if 'invocation' in clean_copy:
del clean_copy['invocation']
# if this task is registering a result, do it now
if result._task.register:
self._send_result(('register_host_var', result._host, result._task.register, clean_copy))
# send callbacks, execute other options based on the result status
# TODO: this should all be cleaned up and probably moved to a sub-function.
# the fact that this sometimes sends a TaskResult and other times
# sends a raw dictionary back may be confusing, but the result vs.
# results implementation for tasks with loops should be cleaned up
# better than this
if result.is_unreachable():
self._send_result(('host_unreachable', result))
elif result.is_failed():
self._send_result(('host_task_failed', result))
elif result.is_skipped():
self._send_result(('host_task_skipped', result))
else:
if result._task.loop:
# this task had a loop, and has more than one result, so
# loop over all of them instead of a single result
result_items = result._result['results']
else:
result_items = [ result._result ]
for result_item in result_items:
# if this task is notifying a handler, do it now
if '_ansible_notify' in result_item:
if result.is_changed():
# The shared dictionary for notified handlers is a proxy, which
# does not detect when sub-objects within the proxy are modified.
# So, per the docs, we reassign the list so the proxy picks up and
# notifies all other threads
for notify in result_item['_ansible_notify']:
self._send_result(('notify_handler', result, notify))
# now remove the notify field from the results, as its no longer needed
result_item.pop('_ansible_notify')
if 'add_host' in result_item:
# this task added a new host (add_host module)
self._send_result(('add_host', result_item))
elif 'add_group' in result_item:
# this task added a new group (group_by module)
self._send_result(('add_group', result._host, result_item))
elif 'ansible_facts' in result_item:
# if this task is registering facts, do that now
item = result_item.get('item', None)
if result._task.action == 'include_vars':
for (key, value) in iteritems(result_item['ansible_facts']):
self._send_result(('set_host_var', result._host, result._task, item, key, value))
else:
self._send_result(('set_host_facts', result._host, result._task, item, result_item['ansible_facts']))
# finally, send the ok for this task
self._send_result(('host_task_ok', result))
except queue.Empty:
pass
except (KeyboardInterrupt, IOError, EOFError):
break
except:
# TODO: we should probably send a proper callback here instead of
# simply dumping a stack trace on the screen
traceback.print_exc()
break