cdist-backup/lib/cdist/core/object.py
Steven Armstrong 12dc0d2bdd cleanup and file system backed properties
Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
2011-10-06 17:15:45 +02:00

157 lines
4.6 KiB
Python

# -*- coding: utf-8 -*-
#
# 2010-2011 Steven Armstrong (steven-cdist at armstrong.cc)
#
# This file is part of cdist.
#
# cdist 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.
#
# cdist 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 cdist. If not, see <http://www.gnu.org/licenses/>.
#
#
import os
import collections
import cdist
import cdist.core.property
DOT_CDIST = '.cdist'
class Object(object):
"""Represents a cdist object.
All interaction with objects in cdist should be done through this class.
Directly accessing an object through the file system from python code is
a bug.
"""
@staticmethod
def base_dir():
"""Return the absolute path to the top level directory where objects
are defined.
Requires the environment variable '__cdist_out_dir' to be set.
"""
try:
base_dir = os.path.join(
os.environ['__cdist_out_dir'],
'object'
)
except KeyError as e:
raise cdist.MissingEnvironmentVariableError(e.args[0])
# FIXME: should directory be created elsewhere?
if not os.path.isdir(base_dir):
os.mkdir(base_dir)
return base_dir
@classmethod
def list_objects(cls):
"""Return a list of object instances"""
for object_name in cls.list_object_names():
type_name = object_name.split(os.sep)[0]
object_id = os.sep.join(object_name.split(os.sep)[1:])
yield cls(Type(type_name), object_id=object_id)
@classmethod
def list_type_names(cls):
"""Return a list of type names"""
return os.listdir(cls.base_dir())
@classmethod
def list_object_names(cls):
"""Return a list of object names"""
for path, dirs, files in os.walk(cls.base_dir()):
# FIXME: use constant instead of string
if DOT_CDIST in dirs:
yield os.path.relpath(path, cls.base_dir())
def __init__(self, type, object_id=None, parameters=None, requirements=None):
self.type = type # instance of Type
self.object_id = object_id
self.name = os.path.join(self.type.name, self.object_id)
self.parameters = parameters or {}
self.requirements = requirements or []
self.__parameters = None
self.__requirements = None
def __repr__(self):
return '<Object %s>' % self.name
@property
def path(self):
return os.path.join(
self.base_dir(),
self.name,
DOT_CDIST
)
### requirements
@property
def requirements(self):
if not self.__requirements:
self.__requirements = cdist.core.property.FileList(os.path.join(self.path, "require"))
return self.__requirements
@requirements.setter
def requirements(self, value):
if isinstance(value, cdist.core.property.FileList):
self.__requirements = value
else:
self.__requirements = cdist.core.property.FileList(os.path.join(self.path, "require"), value)
### /requirements
### parameters
@property
def parameters(self):
if not self.__parameters:
self.__parameters = cdist.core.property.DirectoryDict(os.path.join(self.path, "parameter"))
return self.__parameters
@parameters.setter
def parameters(self, value):
if isinstance(value, cdist.core.property.DirectoryDict):
self.__parameters = value
else:
self.__parameters = cdist.core.property.DirectoryDict(os.path.join(self.path, "parameter"), value)
### /parameters
### changed
@property
def changed(self):
"""Check whether the object has been changed."""
return os.path.isfile(os.path.join(self.path, "changed"))
@changed.setter
def changed(self, value):
"""Change the objects changed status."""
path = os.path.join(self.path, "changed")
if value:
open(path, "w").close()
else:
try:
os.remove(path)
except EnvironmentError:
# ignore
pass
### /changed
# FIXME: implement other properties/methods