rattail/rattail/upgrades.py

92 lines
3.2 KiB
Python

# -*- coding: utf-8; -*-
################################################################################
#
# Rattail -- Retail Software Framework
# Copyright © 2010-2017 Lance Edgar
#
# This file is part of Rattail.
#
# Rattail 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.
#
# Rattail 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
# Rattail. If not, see <http://www.gnu.org/licenses/>.
#
################################################################################
"""
Upgrade handlers
"""
from __future__ import unicode_literals, absolute_import
import os
import subprocess
from rattail.util import load_object
class UpgradeHandler(object):
"""
Base class and default implementation for upgrade handlers.
"""
def __init__(self, config):
self.config = config
def executable(self, upgrade):
"""
This method should return a boolean indicating whether or not execution
should be allowed for the upgrade, given its current condition. The
default simply returns ``True`` unless the upgrade has already been
executed.
"""
if upgrade is None:
return True
return not bool(upgrade.executed)
def execute(self, upgrade, user, progress=None, **kwargs):
"""
Execute the given upgrade, as the given user.
"""
before_path = self.config.upgrade_filepath(upgrade.uuid, filename='requirements.before.txt', makedirs=True)
self.record_requirements_snapshot(before_path)
stdout_path = self.config.upgrade_filepath(upgrade.uuid, filename='stdout.log')
stderr_path = self.config.upgrade_filepath(upgrade.uuid, filename='stderr.log')
cmd = self.config.upgrade_command()
with open(stdout_path, 'wb') as stdout:
with open(stderr_path, 'wb') as stderr:
upgrade.exit_code = subprocess.call(cmd, stdout=stdout, stderr=stderr)
after_path = self.config.upgrade_filepath(upgrade.uuid, filename='requirements.after.txt')
self.record_requirements_snapshot(after_path)
return upgrade.exit_code == 0
def record_requirements_snapshot(self, path):
pip = self.get_pip_path()
logpath = os.path.join(self.config.workdir(), 'pip.log')
with open(path, 'wb') as stdout:
subprocess.call([pip, '--log', logpath, 'freeze'], stdout=stdout)
def get_pip_path(self):
path = os.path.join(self.config.appdir(), os.pardir, 'bin', 'pip')
return os.path.abspath(path)
def get_upgrade_handler(config, default=None):
"""
Returns an upgrade handler object.
"""
spec = config.get('rattail.upgrades', 'handler', default=default)
if spec:
handler = load_object(spec)(config)
else:
handler = UpgradeHandler(config)
return handler