# (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 base64 import json import subprocess import sys import time from ansible.compat.six import iteritems from ansible import constants as C from ansible.errors import AnsibleError, AnsibleParserError, AnsibleUndefinedVariable, AnsibleConnectionFailure from ansible.playbook.conditional import Conditional from ansible.playbook.task import Task from ansible.template import Templar from ansible.utils.encrypt import key_for_hostname from ansible.utils.listify import listify_lookup_plugin_terms from ansible.utils.unicode import to_unicode from ansible.vars.unsafe_proxy import UnsafeProxy __all__ = ['TaskExecutor'] class TaskExecutor: ''' This is the main worker class for the executor pipeline, which handles loading an action plugin to actually dispatch the task to a given host. This class roughly corresponds to the old Runner() class. ''' # Modules that we optimize by squashing loop items into a single call to # the module SQUASH_ACTIONS = frozenset(C.DEFAULT_SQUASH_ACTIONS) def __init__(self, host, task, job_vars, play_context, new_stdin, loader, shared_loader_obj): self._host = host self._task = task self._job_vars = job_vars self._play_context = play_context self._new_stdin = new_stdin self._loader = loader self._shared_loader_obj = shared_loader_obj try: from __main__ import display self._display = display except ImportError: from ansible.utils.display import Display self._display = Display() def run(self): ''' The main executor entrypoint, where we determine if the specified task requires looping and either runs the task with ''' self._display.debug("in run()") try: # lookup plugins need to know if this task is executing from # a role, so that it can properly find files/templates/etc. roledir = None if self._task._role: roledir = self._task._role._role_path self._job_vars['roledir'] = roledir items = self._get_loop_items() if items is not None: if len(items) > 0: item_results = self._run_loop(items) # loop through the item results, and remember the changed/failed # result flags based on any item there. changed = False failed = False for item in item_results: if 'changed' in item and item['changed']: changed = True if 'failed' in item and item['failed']: failed = True # create the overall result item, and set the changed/failed # flags there to reflect the overall result of the loop res = dict(results=item_results) if changed: res['changed'] = True if failed: res['failed'] = True res['msg'] = 'One or more items failed' else: res['msg'] = 'All items completed' else: res = dict(changed=False, skipped=True, skipped_reason='No items in the list', results=[]) else: self._display.debug("calling self._execute()") res = self._execute() self._display.debug("_execute() done") # make sure changed is set in the result, if it's not present if 'changed' not in res: res['changed'] = False def _clean_res(res): if isinstance(res, dict): for k in res.keys(): res[k] = _clean_res(res[k]) elif isinstance(res, list): for idx,item in enumerate(res): res[idx] = _clean_res(item) elif isinstance(res, UnsafeProxy): return res._obj return res self._display.debug("dumping result to json") res = _clean_res(res) self._display.debug("done dumping result, returning") return res except AnsibleError as e: return dict(failed=True, msg=to_unicode(e, nonstring='simplerepr')) finally: try: self._connection.close() except AttributeError: pass except Exception as e: self._display.debug("error closing connection: %s" % to_unicode(e)) def _get_loop_items(self): ''' Loads a lookup plugin to handle the with_* portion of a task (if specified), and returns the items result. ''' # create a copy of the job vars here so that we can modify # them temporarily without changing them too early for other # parts of the code that might still need a pristine version vars_copy = self._job_vars.copy() # now we update them with the play context vars self._play_context.update_vars(vars_copy) templar = Templar(loader=self._loader, shared_loader_obj=self._shared_loader_obj, variables=vars_copy) items = None if self._task.loop: if self._task.loop in self._shared_loader_obj.lookup_loader: #TODO: remove convert_bare true and deprecate this in with_ try: loop_terms = listify_lookup_plugin_terms(terms=self._task.loop_args, templar=templar, loader=self._loader, fail_on_undefined=True, convert_bare=True) except AnsibleUndefinedVariable as e: if 'has no attribute' in str(e): loop_terms = [] self._display.deprecated("Skipping task due to undefined attribute, in the future this will be a fatal error.") else: raise items = self._shared_loader_obj.lookup_loader.get(self._task.loop, loader=self._loader, templar=templar).run(terms=loop_terms, variables=vars_copy) else: raise AnsibleError("Unexpected failure in finding the lookup named '%s' in the available lookup plugins" % self._task.loop) if items: from ansible.vars.unsafe_proxy import UnsafeProxy for idx, item in enumerate(items): if item is not None and not isinstance(item, UnsafeProxy): items[idx] = UnsafeProxy(item) return items def _run_loop(self, items): ''' Runs the task with the loop items specified and collates the result into an array named 'results' which is inserted into the final result along with the item for which the loop ran. ''' results = [] # make copies of the job vars and task so we can add the item to # the variables and re-validate the task with the item variable task_vars = self._job_vars.copy() items = self._squash_items(items, task_vars) for item in items: task_vars['item'] = item try: tmp_task = self._task.copy() tmp_play_context = self._play_context.copy() except AnsibleParserError as e: results.append(dict(failed=True, msg=str(e))) continue # now we swap the internal task and play context with their copies, # execute, and swap them back so we can do the next iteration cleanly (self._task, tmp_task) = (tmp_task, self._task) (self._play_context, tmp_play_context) = (tmp_play_context, self._play_context) res = self._execute(variables=task_vars) (self._task, tmp_task) = (tmp_task, self._task) (self._play_context, tmp_play_context) = (tmp_play_context, self._play_context) # now update the result with the item info, and append the result # to the list of results res['item'] = item results.append(res) return results def _squash_items(self, items, variables): ''' Squash items down to a comma-separated list for certain modules which support it (typically package management modules). ''' if len(items) > 0 and self._task.action in self.SQUASH_ACTIONS: final_items = [] name = self._task.args.pop('name', None) or self._task.args.pop('pkg', None) for item in items: variables['item'] = item templar = Templar(loader=self._loader, shared_loader_obj=self._shared_loader_obj, variables=variables) if self._task.evaluate_conditional(templar, variables): if templar._contains_vars(name): new_item = templar.template(name) final_items.append(new_item) else: final_items.append(item) joined_items = ",".join(final_items) self._task.args['name'] = joined_items return [joined_items] else: return items def _execute(self, variables=None): ''' The primary workhorse of the executor system, this runs the task on the specified host (which may be the delegated_to host) and handles the retry/until and block rescue/always execution ''' if variables is None: variables = self._job_vars templar = Templar(loader=self._loader, shared_loader_obj=self._shared_loader_obj, variables=variables) context_validation_error = None try: # apply the given task's information to the connection info, # which may override some fields already set by the play or # the options specified on the command line self._play_context = self._play_context.set_task_and_variable_override(task=self._task, variables=variables, templar=templar) # fields set from the play/task may be based on variables, so we have to # do the same kind of post validation step on it here before we use it. self._play_context.post_validate(templar=templar) # We also add "magic" variables back into the variables dict to make sure # a certain subset of variables exist. self._play_context.update_vars(variables) except AnsibleError as e: # save the error, which we'll raise later if we don't end up # skipping this task during the conditional evaluation step context_validation_error = e # Evaluate the conditional (if any) for this task, which we do before running # the final task post-validation. We do this before the post validation due to # the fact that the conditional may specify that the task be skipped due to a # variable not being present which would otherwise cause validation to fail try: if not self._task.evaluate_conditional(templar, variables): self._display.debug("when evaluation failed, skipping this task") return dict(changed=False, skipped=True, skip_reason='Conditional check failed', _ansible_no_log=self._play_context.no_log) except AnsibleError: # skip conditional exception in the case of includes as the vars needed might not be avaiable except in the included tasks or due to tags if self._task.action != 'include': raise # if we ran into an error while setting up the PlayContext, raise it now if context_validation_error is not None: raise context_validation_error # if this task is a TaskInclude, we just return now with a success code so the # main thread can expand the task list for the given host if self._task.action == 'include': include_variables = self._task.args.copy() include_file = include_variables.pop('_raw_params', None) if not include_file: return dict(failed=True, msg="No include file was specified to the include") include_file = templar.template(include_file) return dict(include=include_file, include_variables=include_variables) # Now we do final validation on the task, which sets all fields to their final values. self._task.post_validate(templar=templar) if '_variable_params' in self._task.args: variable_params = self._task.args.pop('_variable_params') if isinstance(variable_params, dict): self._display.deprecated("Using variables for task params is unsafe, especially if the variables come from an external source like facts") variable_params.update(self._task.args) self._task.args = variable_params # get the connection and the handler for this execution self._connection = self._get_connection(variables=variables, templar=templar) self._connection.set_host_overrides(host=self._host) self._handler = self._get_action_handler(connection=self._connection, templar=templar) # And filter out any fields which were set to default(omit), and got the omit token value omit_token = variables.get('omit') if omit_token is not None: self._task.args = dict((i[0], i[1]) for i in iteritems(self._task.args) if i[1] != omit_token) # Read some values from the task, so that we can modify them if need be if self._task.until is not None: retries = self._task.retries if retries <= 0: retries = 1 else: retries = 1 delay = self._task.delay if delay < 0: delay = 1 # make a copy of the job vars here, in case we need to update them # with the registered variable value later on when testing conditions vars_copy = variables.copy() self._display.debug("starting attempt loop") result = None for attempt in range(retries): if attempt > 0: self._display.display("FAILED - RETRYING: %s (%d retries left). Result was: %s" % (self._task, retries-attempt, result), color="red") result['attempts'] = attempt + 1 self._display.debug("running the handler") try: result = self._handler.run(task_vars=variables) except AnsibleConnectionFailure as e: return dict(unreachable=True, msg=str(e)) self._display.debug("handler run complete") if self._task.async > 0: # the async_wrapper module returns dumped JSON via its stdout # response, so we parse it here and replace the result try: result = json.loads(result.get('stdout')) except (TypeError, ValueError) as e: return dict(failed=True, msg="The async task did not return valid JSON: %s" % str(e)) if self._task.poll > 0: result = self._poll_async_result(result=result, templar=templar) # update the local copy of vars with the registered value, if specified, # or any facts which may have been generated by the module execution if self._task.register: vars_copy[self._task.register] = result if 'ansible_facts' in result: vars_copy.update(result['ansible_facts']) # create a conditional object to evaluate task conditions cond = Conditional(loader=self._loader) def _evaluate_changed_when_result(result): if self._task.changed_when is not None: cond.when = [ self._task.changed_when ] result['changed'] = cond.evaluate_conditional(templar, vars_copy) def _evaluate_failed_when_result(result): if self._task.failed_when is not None: cond.when = [ self._task.failed_when ] failed_when_result = cond.evaluate_conditional(templar, vars_copy) result['failed_when_result'] = result['failed'] = failed_when_result return failed_when_result return False if self._task.until: cond.when = self._task.until if cond.evaluate_conditional(templar, vars_copy): _evaluate_changed_when_result(result) _evaluate_failed_when_result(result) break elif (self._task.changed_when is not None or self._task.failed_when is not None) and 'skipped' not in result: _evaluate_changed_when_result(result) if _evaluate_failed_when_result(result): break elif 'failed' not in result: if result.get('rc', 0) != 0: result['failed'] = True else: # if the result is not failed, stop trying break if attempt < retries - 1: time.sleep(delay) else: _evaluate_changed_when_result(result) _evaluate_failed_when_result(result) # do the final update of the local variables here, for both registered # values and any facts which may have been created if self._task.register: ### FIXME: # If we remove invocation, we should also be removing _ansible* # and maybe ansible_facts. # Remove invocation from registered vars #if 'invocation' in result: # del result['invocation'] variables[self._task.register] = result if 'ansible_facts' in result: variables.update(result['ansible_facts']) # save the notification target in the result, if it was specified, as # this task may be running in a loop in which case the notification # may be item-specific, ie. "notify: service {{item}}" if self._task.notify is not None: result['_ansible_notify'] = self._task.notify # preserve no_log setting result["_ansible_no_log"] = self._play_context.no_log # and return self._display.debug("attempt loop complete, returning result") return result def _poll_async_result(self, result, templar): ''' Polls for the specified JID to be complete ''' async_jid = result.get('ansible_job_id') if async_jid is None: return dict(failed=True, msg="No job id was returned by the async task") # Create a new psuedo-task to run the async_status module, and run # that (with a sleep for "poll" seconds between each retry) until the # async time limit is exceeded. async_task = Task().load(dict(action='async_status jid=%s' % async_jid)) # Because this is an async task, the action handler is async. However, # we need the 'normal' action handler for the status check, so get it # now via the action_loader normal_handler = self._shared_loader_obj.action_loader.get( 'normal', task=async_task, connection=self._connection, play_context=self._play_context, loader=self._loader, templar=templar, shared_loader_obj=self._shared_loader_obj, ) time_left = self._task.async while time_left > 0: time.sleep(self._task.poll) async_result = normal_handler.run() if int(async_result.get('finished', 0)) == 1 or 'failed' in async_result or 'skipped' in async_result: break time_left -= self._task.poll if int(async_result.get('finished', 0)) != 1: return dict(failed=True, msg="async task did not complete within the requested time") else: return async_result def _get_connection(self, variables, templar): ''' Reads the connection property for the host, and returns the correct connection object from the list of connection plugins ''' if not self._play_context.remote_addr: self._play_context.remote_addr = self._host.address if self._task.delegate_to is not None: # since we're delegating, we don't want to use interpreter values # which would have been set for the original target host for i in variables.keys(): if i.startswith('ansible_') and i.endswith('_interpreter'): del variables[i] # now replace the interpreter values with those that may have come # from the delegated-to host delegated_vars = variables.get('ansible_delegated_vars', dict()).get(self._task.delegate_to, dict()) if isinstance(delegated_vars, dict): for i in delegated_vars: if i.startswith("ansible_") and i.endswith("_interpreter"): variables[i] = delegated_vars[i] conn_type = self._play_context.connection if conn_type == 'smart': conn_type = 'ssh' if sys.platform.startswith('darwin') and self._play_context.password: # due to a current bug in sshpass on OSX, which can trigger # a kernel panic even for non-privileged users, we revert to # paramiko on that OS when a SSH password is specified conn_type = "paramiko" else: # see if SSH can support ControlPersist if not use paramiko try: cmd = subprocess.Popen(['ssh','-o','ControlPersist'], stdout=subprocess.PIPE, stderr=subprocess.PIPE) (out, err) = cmd.communicate() if "Bad configuration option" in err or "Usage:" in err: conn_type = "paramiko" except OSError: conn_type = "paramiko" connection = self._shared_loader_obj.connection_loader.get(conn_type, self._play_context, self._new_stdin) if not connection: raise AnsibleError("the connection plugin '%s' was not found" % conn_type) if self._play_context.accelerate: # launch the accelerated daemon here ssh_connection = connection handler = self._shared_loader_obj.action_loader.get( 'normal', task=self._task, connection=ssh_connection, play_context=self._play_context, loader=self._loader, templar=templar, shared_loader_obj=self._shared_loader_obj, ) key = key_for_hostname(self._play_context.remote_addr) accelerate_args = dict( password=base64.b64encode(key.__str__()), port=self._play_context.accelerate_port, minutes=C.ACCELERATE_DAEMON_TIMEOUT, ipv6=self._play_context.accelerate_ipv6, debug=self._play_context.verbosity, ) connection = self._shared_loader_obj.connection_loader.get('accelerate', self._play_context, self._new_stdin) if not connection: raise AnsibleError("the connection plugin '%s' was not found" % conn_type) try: connection._connect() except AnsibleConnectionFailure: res = handler._execute_module(module_name='accelerate', module_args=accelerate_args, task_vars=variables, delete_remote_tmp=False) connection._connect() return connection def _get_action_handler(self, connection, templar): ''' Returns the correct action plugin to handle the requestion task action ''' if self._task.action in self._shared_loader_obj.action_loader: if self._task.async != 0: raise AnsibleError("async mode is not supported with the %s module" % self._task.action) handler_name = self._task.action elif self._task.async == 0: handler_name = 'normal' else: handler_name = 'async' handler = self._shared_loader_obj.action_loader.get( handler_name, task=self._task, connection=connection, play_context=self._play_context, loader=self._loader, templar=templar, shared_loader_obj=self._shared_loader_obj, ) if not handler: raise AnsibleError("the handler '%s' was not found" % handler_name) return handler