Making the switch to v2

lib/ansible/playbook/role/__init__.py

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+# (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 six import iteritems, string_types
+
+import inspect
+import os
+
+from hashlib import sha1
+from types import NoneType
+
+from ansible.errors import AnsibleError, AnsibleParserError
+from ansible.parsing import DataLoader
+from ansible.playbook.attribute import FieldAttribute
+from ansible.playbook.base import Base
+from ansible.playbook.become import Become
+from ansible.playbook.conditional import Conditional
+from ansible.playbook.helpers import load_list_of_blocks
+from ansible.playbook.role.include import RoleInclude
+from ansible.playbook.role.metadata import RoleMetadata
+from ansible.playbook.taggable import Taggable
+from ansible.plugins import get_all_plugin_loaders
+from ansible.utils.vars import combine_vars
+
+
+__all__ = ['Role', 'ROLE_CACHE', 'hash_params']
+
+# FIXME: this should be a utility function, but can't be a member of
+#        the role due to the fact that it would require the use of self
+#        in a static method. This is also used in the base class for
+#        strategies (ansible/plugins/strategies/__init__.py)
+def hash_params(params):
+    if not isinstance(params, dict):
+        return params
+    else:
+        s = set()
+        for k,v in params.iteritems():
+            if isinstance(v, dict):
+                s.update((k, hash_params(v)))
+            elif isinstance(v, list):
+                things = []
+                for item in v:
+                    things.append(hash_params(item))
+                s.update((k, tuple(things)))
+            else:
+                s.update((k, v))
+        return frozenset(s)
+
+# The role cache is used to prevent re-loading roles, which
+# may already exist. Keys into this cache are the SHA1 hash
+# of the role definition (for dictionary definitions, this
+# will be based on the repr() of the dictionary object)
+ROLE_CACHE = dict()
+
+
+class Role(Base, Become, Conditional, Taggable):
+
+    def __init__(self):
+        self._role_name        = None
+        self._role_path        = None
+        self._role_params      = dict()
+        self._loader           = None
+
+        self._metadata         = None
+        self._play             = None
+        self._parents          = []
+        self._dependencies     = []
+        self._task_blocks      = []
+        self._handler_blocks   = []
+        self._default_vars     = dict()
+        self._role_vars        = dict()
+        self._had_task_run     = False
+        self._completed        = False
+
+        super(Role, self).__init__()
+
+    def __repr__(self):
+        return self.get_name()
+
+    def get_name(self):
+        return self._role_name
+
+    @staticmethod
+    def load(role_include, parent_role=None):
+        # FIXME: add back in the role caching support
+        try:
+            # The ROLE_CACHE is a dictionary of role names, with each entry
+            # containing another dictionary corresponding to a set of parameters
+            # specified for a role as the key and the Role() object itself.
+            # We use frozenset to make the dictionary hashable.
+
+            #hashed_params = frozenset(role_include.get_role_params().iteritems())
+            hashed_params = hash_params(role_include.get_role_params())
+            if role_include.role in ROLE_CACHE:
+                for (entry, role_obj) in ROLE_CACHE[role_include.role].iteritems():
+                    if hashed_params == entry:
+                        if parent_role:
+                            role_obj.add_parent(parent_role)
+                        return role_obj
+
+            r = Role()
+            r._load_role_data(role_include, parent_role=parent_role)
+
+            if role_include.role not in ROLE_CACHE:
+                ROLE_CACHE[role_include.role] = dict()
+
+            ROLE_CACHE[role_include.role][hashed_params] = r
+            return r
+
+        except RuntimeError:
+            # FIXME: needs a better way to access the ds in the role include
+            raise AnsibleError("A recursion loop was detected with the roles specified. Make sure child roles do not have dependencies on parent roles", obj=role_include._ds)
+
+    def _load_role_data(self, role_include, parent_role=None):
+        self._role_name        = role_include.role
+        self._role_path        = role_include.get_role_path()
+        self._role_params      = role_include.get_role_params()
+        self._variable_manager = role_include.get_variable_manager()
+        self._loader           = role_include.get_loader()
+
+        if parent_role:
+            self.add_parent(parent_role)
+
+        # copy over all field attributes, except for when and tags, which
+        # are special cases and need to preserve pre-existing values
+        for (attr_name, _) in iteritems(self._get_base_attributes()):
+            if attr_name not in ('when', 'tags'):
+                setattr(self, attr_name, getattr(role_include, attr_name))
+
+        current_when = getattr(self, 'when')[:]
+        current_when.extend(role_include.when)
+        setattr(self, 'when', current_when)
+        
+        current_tags = getattr(self, 'tags')[:]
+        current_tags.extend(role_include.tags)
+        setattr(self, 'tags', current_tags)
+
+        # dynamically load any plugins from the role directory
+        for name, obj in get_all_plugin_loaders():
+            if obj.subdir:
+                plugin_path = os.path.join(self._role_path, obj.subdir)
+                if os.path.isdir(plugin_path):
+                    obj.add_directory(plugin_path)
+
+        # load the role's other files, if they exist
+        metadata = self._load_role_yaml('meta')
+        if metadata:
+            self._metadata = RoleMetadata.load(metadata, owner=self, loader=self._loader)
+            self._dependencies = self._load_dependencies()
+
+        task_data = self._load_role_yaml('tasks')
+        if task_data:
+            self._task_blocks = load_list_of_blocks(task_data, play=None, role=self, loader=self._loader)
+
+        handler_data = self._load_role_yaml('handlers')
+        if handler_data:
+            self._handler_blocks = load_list_of_blocks(handler_data, play=None, role=self, loader=self._loader)
+
+        # vars and default vars are regular dictionaries
+        self._role_vars  = self._load_role_yaml('vars')
+        if not isinstance(self._role_vars, (dict, NoneType)):
+            raise AnsibleParserError("The vars/main.yml file for role '%s' must contain a dictionary of variables" % self._role_name)
+        elif self._role_vars is None:
+            self._role_vars = dict()
+
+        self._default_vars = self._load_role_yaml('defaults')
+        if not isinstance(self._default_vars, (dict, NoneType)):
+            raise AnsibleParserError("The default/main.yml file for role '%s' must contain a dictionary of variables" % self._role_name)
+        elif self._default_vars is None:
+            self._default_vars = dict()
+
+    def _load_role_yaml(self, subdir):
+        file_path = os.path.join(self._role_path, subdir)
+        if self._loader.path_exists(file_path) and self._loader.is_directory(file_path):
+            main_file = self._resolve_main(file_path)
+            if self._loader.path_exists(main_file):
+                return self._loader.load_from_file(main_file)
+        return None
+
+    def _resolve_main(self, basepath):
+        ''' flexibly handle variations in main filenames '''
+        possible_mains = (
+            os.path.join(basepath, 'main.yml'),
+            os.path.join(basepath, 'main.yaml'),
+            os.path.join(basepath, 'main.json'),
+            os.path.join(basepath, 'main'),
+        )
+
+        if sum([self._loader.is_file(x) for x in possible_mains]) > 1:
+            raise AnsibleError("found multiple main files at %s, only one allowed" % (basepath))
+        else:
+            for m in possible_mains:
+                if self._loader.is_file(m):
+                    return m # exactly one main file
+            return possible_mains[0] # zero mains (we still need to return something)
+
+    def _load_dependencies(self):
+        '''
+        Recursively loads role dependencies from the metadata list of
+        dependencies, if it exists
+        '''
+
+        deps = []
+        if self._metadata:
+            for role_include in self._metadata.dependencies:
+                r = Role.load(role_include, parent_role=self)
+                deps.append(r)
+
+        return deps
+
+    #------------------------------------------------------------------------------
+    # other functions
+
+    def add_parent(self, parent_role):
+        ''' adds a role to the list of this roles parents '''
+        assert isinstance(parent_role, Role)
+
+        if parent_role not in self._parents:
+            self._parents.append(parent_role)
+
+    def get_parents(self):
+        return self._parents
+
+    def get_default_vars(self):
+        # FIXME: get these from dependent roles too
+        default_vars = dict()
+        for dep in self.get_all_dependencies():
+            default_vars = combine_vars(default_vars, dep.get_default_vars())
+        default_vars = combine_vars(default_vars, self._default_vars)
+        return default_vars
+
+    def get_inherited_vars(self):
+        inherited_vars = dict()
+        for parent in self._parents:
+            inherited_vars = combine_vars(inherited_vars, parent.get_inherited_vars())
+            inherited_vars = combine_vars(inherited_vars, parent._role_vars)
+            inherited_vars = combine_vars(inherited_vars, parent._role_params)
+        return inherited_vars
+
+    def get_vars(self):
+        all_vars = self.get_inherited_vars()
+
+        for dep in self.get_all_dependencies():
+            all_vars = combine_vars(all_vars, dep.get_vars())
+
+        all_vars = combine_vars(all_vars, self._role_vars)
+        all_vars = combine_vars(all_vars, self._role_params)
+
+        return all_vars
+
+    def get_direct_dependencies(self):
+        return self._dependencies[:]
+
+    def get_all_dependencies(self):
+        '''
+        Returns a list of all deps, built recursively from all child dependencies,
+        in the proper order in which they should be executed or evaluated.
+        '''
+
+        child_deps  = []
+
+        for dep in self.get_direct_dependencies():
+            for child_dep in dep.get_all_dependencies():
+                child_deps.append(child_dep)
+            child_deps.append(dep)
+
+        return child_deps
+
+    def get_task_blocks(self):
+        return self._task_blocks[:]
+
+    def get_handler_blocks(self):
+        return self._handler_blocks[:]
+
+    def has_run(self):
+        '''
+        Returns true if this role has been iterated over completely and
+        at least one task was run
+        '''
+
+        return self._had_task_run and self._completed
+
+    def compile(self, play, dep_chain=[]):
+        '''
+        Returns the task list for this role, which is created by first
+        recursively compiling the tasks for all direct dependencies, and
+        then adding on the tasks for this role.
+
+        The role compile() also remembers and saves the dependency chain
+        with each task, so tasks know by which route they were found, and
+        can correctly take their parent's tags/conditionals into account.
+        '''
+
+        block_list = []
+
+        # update the dependency chain here
+        new_dep_chain = dep_chain + [self]
+
+        deps = self.get_direct_dependencies()
+        for dep in deps:
+            dep_blocks = dep.compile(play=play, dep_chain=new_dep_chain)
+            for dep_block in dep_blocks:
+                new_dep_block = dep_block.copy()
+                new_dep_block._dep_chain = new_dep_chain
+                new_dep_block._play = play
+                block_list.append(new_dep_block)
+
+        block_list.extend(self._task_blocks)
+
+        return block_list
+
+    def serialize(self, include_deps=True):
+        res = super(Role, self).serialize()
+
+        res['_role_name']    = self._role_name
+        res['_role_path']    = self._role_path
+        res['_role_vars']    = self._role_vars
+        res['_role_params']  = self._role_params
+        res['_default_vars'] = self._default_vars
+        res['_had_task_run'] = self._had_task_run
+        res['_completed']    = self._completed
+
+        if self._metadata:
+            res['_metadata'] = self._metadata.serialize()
+
+        if include_deps:
+            deps = []
+            for role in self.get_direct_dependencies():
+                deps.append(role.serialize())
+            res['_dependencies'] = deps
+
+        parents = []
+        for parent in self._parents:
+            parents.append(parent.serialize(include_deps=False))
+        res['_parents'] = parents
+
+        return res
+
+    def deserialize(self, data, include_deps=True):
+        self._role_name    = data.get('_role_name', '')
+        self._role_path    = data.get('_role_path', '')
+	self._role_vars    = data.get('_role_vars', dict())
+        self._role_params  = data.get('_role_params', dict())
+        self._default_vars = data.get('_default_vars', dict())
+        self._had_task_run = data.get('_had_task_run', False)
+        self._completed    = data.get('_completed', False)
+
+        if include_deps:
+            deps = []
+            for dep in data.get('_dependencies', []):
+                r = Role()
+                r.deserialize(dep)
+                deps.append(r)
+            setattr(self, '_dependencies', deps)
+
+        parent_data = data.get('_parents', [])
+        parents = []
+        for parent in parent_data:
+            r = Role()
+            r.deserialize(parent, include_deps=False)
+            parents.append(r)
+        setattr(self, '_parents', parents)
+
+        metadata_data = data.get('_metadata')
+        if metadata_data:
+            m = RoleMetadata()
+            m.deserialize(metadata_data)
+            self._metadata = m
+
+        super(Role, self).deserialize(data)
+
+    def set_loader(self, loader):
+        self._loader = loader
+        for parent in self._parents:
+            parent.set_loader(loader)
+        for dep in self.get_direct_dependencies():
+            dep.set_loader(loader)
+