# (c) 2012-2014, Michael DeHaan # # 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 . # Make coding more python3-ish from __future__ import (absolute_import, division, print_function) __metaclass__ = type import multiprocessing import os import socket import sys from ansible.errors import AnsibleError from ansible.executor.connection_info import ConnectionInformation from ansible.executor.play_iterator import PlayIterator from ansible.executor.process.worker import WorkerProcess from ansible.executor.process.result import ResultProcess from ansible.plugins import callback_loader, strategy_loader from ansible.utils.debug import debug __all__ = ['TaskQueueManager'] class TaskQueueManager: ''' This class handles the multiprocessing requirements of Ansible by creating a pool of worker forks, a result handler fork, and a manager object with shared datastructures/queues for coordinating work between all processes. The queue manager is responsible for loading the play strategy plugin, which dispatches the Play's tasks to hosts. ''' def __init__(self, inventory, callback, variable_manager, loader, options): self._inventory = inventory self._variable_manager = variable_manager self._loader = loader self._options = options # a special flag to help us exit cleanly self._terminated = False # this dictionary is used to keep track of notified handlers self._notified_handlers = dict() # dictionaries to keep track of failed/unreachable hosts self._failed_hosts = dict() self._unreachable_hosts = dict() self._final_q = multiprocessing.Queue() # FIXME: hard-coded the default callback plugin here, which # should be configurable. self._callback = callback_loader.get(callback) # create the pool of worker threads, based on the number of forks specified try: fileno = sys.stdin.fileno() except ValueError: fileno = None self._workers = [] for i in range(self._options.forks): # duplicate stdin, if possible new_stdin = None if fileno is not None: try: new_stdin = os.fdopen(os.dup(fileno)) except OSError, e: # couldn't dupe stdin, most likely because it's # not a valid file descriptor, so we just rely on # using the one that was passed in pass main_q = multiprocessing.Queue() rslt_q = multiprocessing.Queue() prc = WorkerProcess(self, main_q, rslt_q, loader, new_stdin) prc.start() self._workers.append((prc, main_q, rslt_q)) self._result_prc = ResultProcess(self._final_q, self._workers) self._result_prc.start() def _initialize_notified_handlers(self, handlers): ''' Clears and initializes the shared notified handlers dict with entries for each handler in the play, which is an empty array that will contain inventory hostnames for those hosts triggering the handler. ''' # Zero the dictionary first by removing any entries there. # Proxied dicts don't support iteritems, so we have to use keys() for key in self._notified_handlers.keys(): del self._notified_handlers[key] # FIXME: there is a block compile helper for this... handler_list = [] for handler_block in handlers: handler_list.extend(handler_block.compile()) # then initalize it with the handler names from the handler list for handler in handler_list: self._notified_handlers[handler.get_name()] = [] def run(self, play): ''' Iterates over the roles/tasks in a play, using the given (or default) strategy for queueing tasks. The default is the linear strategy, which operates like classic Ansible by keeping all hosts in lock-step with a given task (meaning no hosts move on to the next task until all hosts are done with the current task). ''' connection_info = ConnectionInformation(play, self._options) self._callback.set_connection_info(connection_info) # run final validation on the play now, to make sure fields are templated # FIXME: is this even required? Everything is validated and merged at the # task level, so else in the play needs to be templated #all_vars = self._vmw.get_vars(loader=self._dlw, play=play) #all_vars = self._vmw.get_vars(loader=self._loader, play=play) #play.post_validate(all_vars=all_vars) self._callback.playbook_on_play_start(play.name) # initialize the shared dictionary containing the notified handlers self._initialize_notified_handlers(play.handlers) # load the specified strategy (or the default linear one) strategy = strategy_loader.get(play.strategy, self) if strategy is None: raise AnsibleError("Invalid play strategy specified: %s" % play.strategy, obj=play._ds) # build the iterator iterator = PlayIterator(inventory=self._inventory, play=play) # and run the play using the strategy return strategy.run(iterator, connection_info) def cleanup(self): debug("RUNNING CLEANUP") self.terminate() self._final_q.close() self._result_prc.terminate() for (worker_prc, main_q, rslt_q) in self._workers: rslt_q.close() main_q.close() worker_prc.terminate() def get_inventory(self): return self._inventory def get_callback(self): return self._callback def get_variable_manager(self): return self._variable_manager def get_loader(self): return self._loader def get_server_pipe(self): return self._server_pipe def get_client_pipe(self): return self._client_pipe def get_pending_results(self): return self._pending_results def get_allow_processing(self): return self._allow_processing def get_notified_handlers(self): return self._notified_handlers def get_workers(self): return self._workers[:] def terminate(self): self._terminated = True