Source code for ansible.template.vars

# (c) 2012, 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 ansible.compat.six import iteritems
from jinja2.utils import missing
from ansible.utils.unicode import to_unicode

__all__ = ['AnsibleJ2Vars']


[docs]class AnsibleJ2Vars: ''' Helper class to template all variable content before jinja2 sees it. This is done by hijacking the variable storage that jinja2 uses, and overriding __contains__ and __getitem__ to look like a dict. Added bonus is avoiding duplicating the large hashes that inject tends to be. To facilitate using builtin jinja2 things like range, globals are also handled here. ''' def __init__(self, templar, globals, locals=None, *extras): ''' Initializes this object with a valid Templar() object, as well as several dictionaries of variables representing different scopes (in jinja2 terminology). ''' self._templar = templar self._globals = globals self._extras = extras self._locals = dict() if isinstance(locals, dict): for key, val in iteritems(locals): if key[:2] == 'l_' and val is not missing: self._locals[key[2:]] = val def __contains__(self, k): if k in self._templar._available_variables: return True if k in self._locals: return True for i in self._extras: if k in i: return True if k in self._globals: return True return False def __getitem__(self, varname): if varname not in self._templar._available_variables: if varname in self._locals: return self._locals[varname] for i in self._extras: if varname in i: return i[varname] if varname in self._globals: return self._globals[varname] else: raise KeyError("undefined variable: %s" % varname) variable = self._templar._available_variables[varname] # HostVars is special, return it as-is, as is the special variable # 'vars', which contains the vars structure from ansible.vars.hostvars import HostVars if isinstance(variable, dict) and varname == "vars" or isinstance(variable, HostVars): return variable else: value = None try: value = self._templar.template(variable) except Exception as e: raise type(e)(to_unicode(variable) + ': ' + e.message) return value
[docs] def add_locals(self, locals): ''' If locals are provided, create a copy of self containing those locals in addition to what is already in this variable proxy. ''' if locals is None: return self return AnsibleJ2Vars(self._templar, self._globals, locals=locals, *self._extras)