# (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 tempfile from ansible import constants as C from ansible.compat.six import string_types from ansible.errors import AnsibleError from ansible.executor.play_iterator import PlayIterator from ansible.executor.stats import AggregateStats from ansible.module_utils._text import to_text from ansible.playbook.block import Block from ansible.playbook.play_context import PlayContext from ansible.plugins import callback_loader, strategy_loader, module_loader from ansible.plugins.callback import CallbackBase from ansible.template import Templar from ansible.utils.helpers import pct_to_int from ansible.vars.hostvars import HostVars try: from __main__ import display except ImportError: from ansible.utils.display import Display display = Display() __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. ''' RUN_OK = 0 RUN_ERROR = 1 RUN_FAILED_HOSTS = 2 RUN_UNREACHABLE_HOSTS = 4 RUN_FAILED_BREAK_PLAY = 8 RUN_UNKNOWN_ERROR = 255 def __init__(self, inventory, variable_manager, loader, options, passwords, stdout_callback=None, run_additional_callbacks=True, run_tree=False): self._inventory = inventory self._variable_manager = variable_manager self._loader = loader self._options = options self._stats = AggregateStats() self.passwords = passwords self._stdout_callback = stdout_callback self._run_additional_callbacks = run_additional_callbacks self._run_tree = run_tree self._callbacks_loaded = False self._callback_plugins = [] self._start_at_done = False # make sure the module path (if specified) is parsed and # added to the module_loader object if options.module_path is not None: for path in options.module_path.split(os.pathsep): module_loader.add_directory(path) # 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() self._listening_handlers = dict() # dictionaries to keep track of failed/unreachable hosts self._failed_hosts = dict() self._unreachable_hosts = dict() self._final_q = multiprocessing.Queue() # A temporary file (opened pre-fork) used by connection # plugins for inter-process locking. self._connection_lockfile = tempfile.TemporaryFile() def _initialize_processes(self, num): self._workers = [] for i in range(num): rslt_q = multiprocessing.Queue() self._workers.append([None, rslt_q]) def _initialize_notified_handlers(self, play): ''' 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() self._notified_handlers.clear() self._listening_handlers.clear() def _process_block(b): temp_list = [] for t in b.block: if isinstance(t, Block): temp_list.extend(_process_block(t)) else: temp_list.append(t) return temp_list handler_list = [] for handler_block in play.handlers: handler_list.extend(_process_block(handler_block)) # then initialize it with the given handler list for handler in handler_list: if handler not in self._notified_handlers: self._notified_handlers[handler] = [] if handler.listen: listeners = handler.listen if not isinstance(listeners, list): listeners = [ listeners ] for listener in listeners: if listener not in self._listening_handlers: self._listening_handlers[listener] = [] # if the handler has a name, we append it to the list of listening # handlers, otherwise we use the uuid to avoid trampling on other # nameless listeners if handler.name: self._listening_handlers[listener].append(handler.get_name()) else: self._listening_handlers[listener].append(handler._uuid) def load_callbacks(self): ''' Loads all available callbacks, with the exception of those which utilize the CALLBACK_TYPE option. When CALLBACK_TYPE is set to 'stdout', only one such callback plugin will be loaded. ''' if self._callbacks_loaded: return stdout_callback_loaded = False if self._stdout_callback is None: self._stdout_callback = C.DEFAULT_STDOUT_CALLBACK if isinstance(self._stdout_callback, CallbackBase): stdout_callback_loaded = True elif isinstance(self._stdout_callback, string_types): if self._stdout_callback not in callback_loader: raise AnsibleError("Invalid callback for stdout specified: %s" % self._stdout_callback) else: self._stdout_callback = callback_loader.get(self._stdout_callback) stdout_callback_loaded = True else: raise AnsibleError("callback must be an instance of CallbackBase or the name of a callback plugin") for callback_plugin in callback_loader.all(class_only=True): if hasattr(callback_plugin, 'CALLBACK_VERSION') and callback_plugin.CALLBACK_VERSION >= 2.0: # we only allow one callback of type 'stdout' to be loaded, so check # the name of the current plugin and type to see if we need to skip # loading this callback plugin callback_type = getattr(callback_plugin, 'CALLBACK_TYPE', None) callback_needs_whitelist = getattr(callback_plugin, 'CALLBACK_NEEDS_WHITELIST', False) (callback_name, _) = os.path.splitext(os.path.basename(callback_plugin._original_path)) if callback_type == 'stdout': if callback_name != self._stdout_callback or stdout_callback_loaded: continue stdout_callback_loaded = True elif callback_name == 'tree' and self._run_tree: pass elif not self._run_additional_callbacks or (callback_needs_whitelist and ( C.DEFAULT_CALLBACK_WHITELIST is None or callback_name not in C.DEFAULT_CALLBACK_WHITELIST)): continue self._callback_plugins.append(callback_plugin()) self._callbacks_loaded = True 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). ''' if not self._callbacks_loaded: self.load_callbacks() all_vars = self._variable_manager.get_vars(loader=self._loader, play=play) templar = Templar(loader=self._loader, variables=all_vars) new_play = play.copy() new_play.post_validate(templar) new_play.handlers = new_play.compile_roles_handlers() + new_play.handlers self.hostvars = HostVars( inventory=self._inventory, variable_manager=self._variable_manager, loader=self._loader, ) # Fork # of forks, # of hosts or serial, whichever is lowest num_hosts = len(self._inventory.get_hosts(new_play.hosts, ignore_restrictions=True)) max_serial = 0 if new_play.serial: # the play has not been post_validated here, so we may need # to convert the scalar value to a list at this point serial_items = new_play.serial if not isinstance(serial_items, list): serial_items = [serial_items] max_serial = max([pct_to_int(x, num_hosts) for x in serial_items]) contenders = [self._options.forks, max_serial, num_hosts] contenders = [v for v in contenders if v is not None and v > 0] self._initialize_processes(min(contenders)) play_context = PlayContext(new_play, self._options, self.passwords, self._connection_lockfile.fileno()) for callback_plugin in self._callback_plugins: if hasattr(callback_plugin, 'set_play_context'): callback_plugin.set_play_context(play_context) self.send_callback('v2_playbook_on_play_start', new_play) # initialize the shared dictionary containing the notified handlers self._initialize_notified_handlers(new_play) # load the specified strategy (or the default linear one) strategy = strategy_loader.get(new_play.strategy, self) if strategy is None: raise AnsibleError("Invalid play strategy specified: %s" % new_play.strategy, obj=play._ds) # build the iterator iterator = PlayIterator( inventory=self._inventory, play=new_play, play_context=play_context, variable_manager=self._variable_manager, all_vars=all_vars, start_at_done = self._start_at_done, ) # Because the TQM may survive multiple play runs, we start by marking # any hosts as failed in the iterator here which may have been marked # as failed in previous runs. Then we clear the internal list of failed # hosts so we know what failed this round. for host_name in self._failed_hosts.keys(): host = self._inventory.get_host(host_name) iterator.mark_host_failed(host) self.clear_failed_hosts() # during initialization, the PlayContext will clear the start_at_task # field to signal that a matching task was found, so check that here # and remember it so we don't try to skip tasks on future plays if getattr(self._options, 'start_at_task', None) is not None and play_context.start_at_task is None: self._start_at_done = True # and run the play using the strategy and cleanup on way out play_return = strategy.run(iterator, play_context) # now re-save the hosts that failed from the iterator to our internal list for host_name in iterator.get_failed_hosts(): self._failed_hosts[host_name] = True strategy.cleanup() self._cleanup_processes() return play_return def cleanup(self): display.debug("RUNNING CLEANUP") self.terminate() self._final_q.close() self._cleanup_processes() def _cleanup_processes(self): if hasattr(self, '_workers'): for (worker_prc, rslt_q) in self._workers: rslt_q.close() if worker_prc and worker_prc.is_alive(): try: worker_prc.terminate() except AttributeError: pass def clear_failed_hosts(self): self._failed_hosts = dict() def get_inventory(self): return self._inventory def get_variable_manager(self): return self._variable_manager def get_loader(self): return self._loader def get_workers(self): return self._workers[:] def terminate(self): self._terminated = True def has_dead_workers(self): # [, # defunct = False for idx,x in enumerate(self._workers): if hasattr(x[0], 'exitcode'): if x[0].exitcode in [-9, -15]: defunct = True return defunct def send_callback(self, method_name, *args, **kwargs): for callback_plugin in [self._stdout_callback] + self._callback_plugins: # a plugin that set self.disabled to True will not be called # see osx_say.py example for such a plugin if getattr(callback_plugin, 'disabled', False): continue # try to find v2 method, fallback to v1 method, ignore callback if no method found methods = [] for possible in [method_name, 'v2_on_any']: gotit = getattr(callback_plugin, possible, None) if gotit is None: gotit = getattr(callback_plugin, possible.replace('v2_',''), None) if gotit is not None: methods.append(gotit) for method in methods: try: # Previously, the `v2_playbook_on_start` callback API did not accept # any arguments. In recent versions of the v2 callback API, the play- # book that started execution is given. In order to support both of # these method signatures, we need to use this `inspect` hack to send # no arguments to the methods that don't accept them. This way, we can # not break backwards compatibility until that API is deprecated. # FIXME: target for removal and revert to the original code here after a year (2017-01-14) if method_name == 'v2_playbook_on_start': import inspect argspec = inspect.getargspec(method) if argspec.args == ['self']: method() else: method(*args, **kwargs) else: method(*args, **kwargs) except Exception as e: # TODO: add config toggle to make this fatal or not? display.warning(u"Failure using method (%s) in callback plugin (%s): %s" % (to_text(method_name), to_text(callback_plugin), to_text(e))) from traceback import format_tb from sys import exc_info display.debug('Callback Exception: \n' + ' '.join(format_tb(exc_info()[2])))