normalized plugin paths and names and configs

lib/ansible/plugins/strategy/free.py

@@ -0,0 +1,184 @@
+# (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
+
+import time
+
+from ansible.errors import *
+from ansible.playbook.included_file import IncludedFile
+from ansible.plugins.strategies import StrategyBase
+
+try:
+    from __main__ import display
+except ImportError:
+    from ansible.utils.display import Display
+    display = Display()
+
+class StrategyModule(StrategyBase):
+
+    def run(self, iterator, play_context):
+        '''
+        The "free" strategy is a bit more complex, in that it allows tasks to
+        be sent to hosts as quickly as they can be processed. This means that
+        some hosts may finish very quickly if run tasks result in little or no
+        work being done versus other systems.
+
+        The algorithm used here also tries to be more "fair" when iterating
+        through hosts by remembering the last host in the list to be given a task
+        and starting the search from there as opposed to the top of the hosts
+        list again, which would end up favoring hosts near the beginning of the
+        list.
+        '''
+
+        # the last host to be given a task
+        last_host = 0
+
+        result = True
+
+        work_to_do = True
+        while work_to_do and not self._tqm._terminated:
+
+            hosts_left = [host for host in self._inventory.get_hosts(iterator._play.hosts) if host.name not in self._tqm._unreachable_hosts]
+            if len(hosts_left) == 0:
+                self._tqm.send_callback('v2_playbook_on_no_hosts_remaining')
+                result = False
+                break
+
+            work_to_do = False        # assume we have no more work to do
+            starting_host = last_host # save current position so we know when we've
+                                      # looped back around and need to break
+
+            # try and find an unblocked host with a task to run
+            host_results = []
+            while True:
+                host = hosts_left[last_host]
+                self._display.debug("next free host: %s" % host)
+                host_name = host.get_name()
+
+                # peek at the next task for the host, to see if there's
+                # anything to do do for this host
+                (state, task) = iterator.get_next_task_for_host(host, peek=True)
+                self._display.debug("free host state: %s" % state)
+                self._display.debug("free host task: %s" % task)
+                if host_name not in self._tqm._failed_hosts and host_name not in self._tqm._unreachable_hosts and task:
+
+                    # set the flag so the outer loop knows we've still found
+                    # some work which needs to be done
+                    work_to_do = True
+
+                    self._display.debug("this host has work to do")
+
+                    # check to see if this host is blocked (still executing a previous task)
+                    if not host_name in self._blocked_hosts or not self._blocked_hosts[host_name]:
+                        # pop the task, mark the host blocked, and queue it
+                        self._blocked_hosts[host_name] = True
+                        (state, task) = iterator.get_next_task_for_host(host)
+
+                        self._display.debug("getting variables")
+                        task_vars = self._variable_manager.get_vars(loader=self._loader, play=iterator._play, host=host, task=task)
+                        self._display.debug("done getting variables")
+
+                        # check to see if this task should be skipped, due to it being a member of a
+                        # role which has already run (and whether that role allows duplicate execution)
+                        if task._role and task._role.has_run(host):
+                            # If there is no metadata, the default behavior is to not allow duplicates,
+                            # if there is metadata, check to see if the allow_duplicates flag was set to true
+                            if task._role._metadata is None or task._role._metadata and not task._role._metadata.allow_duplicates:
+                                self._display.debug("'%s' skipped because role has already run" % task)
+                                continue
+
+                        if not task.evaluate_tags(play_context.only_tags, play_context.skip_tags, task_vars) and task.action != 'setup':
+                            self._display.debug("'%s' failed tag evaluation" % task)
+                            continue
+
+                        if task.action == 'meta':
+                            # meta tasks store their args in the _raw_params field of args,
+                            # since they do not use k=v pairs, so get that
+                            meta_action = task.args.get('_raw_params')
+                            if meta_action == 'noop':
+                                # FIXME: issue a callback for the noop here?
+                                continue
+                            elif meta_action == 'flush_handlers':
+                                # FIXME: in the 'free' mode, flushing handlers should result in
+                                #        only those handlers notified for the host doing the flush
+                                self.run_handlers(iterator, play_context)
+                            else:
+                                raise AnsibleError("invalid meta action requested: %s" % meta_action, obj=task._ds)
+
+                            self._blocked_hosts[host_name] = False
+                        else:
+                            # handle step if needed, skip meta actions as they are used internally
+                            if not self._step or self._take_step(task, host_name):
+                                self._tqm.send_callback('v2_playbook_on_task_start', task, is_conditional=False)
+                                self._queue_task(host, task, task_vars, play_context)
+
+                # move on to the next host and make sure we
+                # haven't gone past the end of our hosts list
+                last_host += 1
+                if last_host > len(hosts_left) - 1:
+                    last_host = 0
+
+                # if we've looped around back to the start, break out
+                if last_host == starting_host:
+                    break
+
+            results = self._process_pending_results(iterator)
+            host_results.extend(results)
+
+            try:
+                included_files = IncludedFile.process_include_results(host_results, self._tqm, iterator=iterator, loader=self._loader, variable_manager=self._variable_manager)
+            except AnsibleError as e:
+                return False
+
+            if len(included_files) > 0:
+                for included_file in included_files:
+                    # included hosts get the task list while those excluded get an equal-length
+                    # list of noop tasks, to make sure that they continue running in lock-step
+                    try:
+                        new_blocks = self._load_included_file(included_file, iterator=iterator)
+                    except AnsibleError as e:
+                        for host in included_file._hosts:
+                            iterator.mark_host_failed(host)
+                        self._display.warning(str(e))
+                        continue
+
+                    for host in hosts_left:
+                        if host in included_file._hosts:
+                            task_vars = self._variable_manager.get_vars(loader=self._loader, play=iterator._play, host=host, task=included_file._task)
+                            final_blocks = []
+                            for new_block in new_blocks:
+                                final_blocks.append(new_block.filter_tagged_tasks(play_context, task_vars))
+                            iterator.add_tasks(host, final_blocks)
+
+            # pause briefly so we don't spin lock
+            time.sleep(0.05)
+
+        try:
+            results = self._wait_on_pending_results(iterator)
+            host_results.extend(results)
+        except Exception as e:
+            # FIXME: ctrl+c can cause some failures here, so catch them
+            #        with the appropriate error type
+            pass
+
+        # run the base class run() method, which executes the cleanup function
+        # and runs any outstanding handlers which have been triggered
+        return super(StrategyModule, self).run(iterator, play_context, result)
+