cdist/lib/cdist/emulator.py
Steven Armstrong d0123acc2a implement singleton as requirement
Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
2011-11-03 15:44:51 +01:00

183 lines
6.6 KiB
Python

# -*- coding: utf-8 -*-
#
# 2011 Nico Schottelius (nico-cdist at schottelius.org)
#
# 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 argparse
import logging
import os
import cdist
from cdist import core
class IllegalRequirementError(cdist.Error):
def __init__(self, requirement, message=None):
self.requirement = requirement
self.message = message or 'Illegal requirement'
def __str__(self):
return '%s: %s' % (self.message, self.requirement)
class Emulator(object):
def __init__(self, argv):
self.argv = argv
self.object_id = False
self.global_path = os.environ['__global']
self.object_source = os.environ['__cdist_manifest']
self.target_host = os.environ['__target_host']
self.type_base_path = os.environ['__cdist_type_base_path']
self.object_base_path = os.path.join(self.global_path, "object")
self.type_name = os.path.basename(argv[0])
self.cdist_type = core.Type(self.type_base_path, self.type_name)
self.__init_log()
def filter(self, record):
"""Add hostname and object to logs via logging Filter"""
prefix = self.target_host + ": (emulator)"
if self.object_id:
prefix = prefix + " " + self.type_name + "/" + self.object_id
record.msg = prefix + ": " + record.msg
return True
def run(self):
"""Emulate type commands (i.e. __file and co)"""
if '__install' in os.environ:
if not self.cdist_type.is_install:
self.log.debug("Running in install mode, ignoring non install type")
return True
self.commandline()
self.setup_object()
self.record_requirements()
self.log.debug("Finished %s %s" % (self.cdist_object.path, self.parameters))
def __init_log(self):
"""Setup logging facility"""
logformat = '%(levelname)s: %(message)s'
logging.basicConfig(format=logformat)
if '__cdist_debug' in os.environ:
logging.root.setLevel(logging.DEBUG)
else:
logging.root.setLevel(logging.INFO)
self.log = logging.getLogger(__name__)
self.log.addFilter(self)
def commandline(self):
"""Parse command line"""
parser = argparse.ArgumentParser(add_help=False)
for parameter in self.cdist_type.optional_parameters:
argument = "--" + parameter
parser.add_argument(argument, action='store', required=False)
for parameter in self.cdist_type.required_parameters:
argument = "--" + parameter
parser.add_argument(argument, action='store', required=True)
# If not singleton support one positional parameter
if not self.cdist_type.is_singleton:
parser.add_argument("object_id", nargs=1)
# And finally parse/verify parameter
self.args = parser.parse_args(self.argv[1:])
self.log.debug('Args: %s' % self.args)
def setup_object(self):
# FIXME: verify object id
# Setup object_id
if self.cdist_type.is_singleton:
self.object_id = "singleton"
else:
self.object_id = self.args.object_id[0]
del self.args.object_id
# strip leading slash from object_id
self.object_id = self.object_id.lstrip('/')
# Instantiate the cdist object we are defining
self.cdist_object = core.Object(self.cdist_type, self.object_base_path, self.object_id)
# Create object with given parameters
self.parameters = {}
for key,value in vars(self.args).items():
if value is not None:
self.parameters[key] = value
if self.cdist_object.exists:
if self.cdist_object.parameters != self.parameters:
raise cdist.Error("Object %s already exists with conflicting parameters:\n%s: %s\n%s: %s"
% (self.cdist_object, " ".join(self.cdist_object.source), self.cdist_object.parameters, self.object_source, self.parameters)
)
else:
self.cdist_object.create()
self.cdist_object.parameters = self.parameters
def record_requirements(self):
"""record requirements"""
if "require" in os.environ:
requirements = os.environ['require']
self.log.debug("reqs = " + requirements)
for requirement in requirements.split(" "):
# Ignore empty fields - probably the only field anyway
if len(requirement) == 0:
continue
self.log.debug("Recording requirement: " + requirement)
requirement_parts = requirement.split(os.sep, 1)
requirement_type_name = requirement_parts[0]
try:
requirement_object_id = requirement_parts[1]
except IndexError:
# no object id, assume singleton
requirement_object_id = 'singleton'
# Remove leading / from object id
requirement_object_id = requirement_object_id.lstrip('/')
# Instantiate type which fails if type does not exist
requirement_type = core.Type(self.type_base_path, requirement_type_name)
if requirement_object_id == 'singleton' \
and not requirement_type.is_singleton:
raise IllegalRequirementError(requirement, "Missing object_id and type is not a singleton.")
# Instantiate object which fails if the object_id is illegal
requirement_object = core.Object(requirement_type, self.object_base_path, requirement_object_id)
# Construct cleaned up requirement with only one / :-)
requirement = requirement_type_name + '/' + requirement_object_id
self.cdist_object.requirements.append(requirement)
# Record / Append source
self.cdist_object.source.append(self.object_source)