380 lines
14 KiB
Python
380 lines
14 KiB
Python
# Copyright 2014-2015 Canonical Limited.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
import os
|
|
|
|
import six
|
|
|
|
from charmhelpers.fetch import apt_install, apt_update
|
|
from charmhelpers.core.hookenv import (
|
|
log,
|
|
ERROR,
|
|
INFO,
|
|
TRACE
|
|
)
|
|
from charmhelpers.contrib.openstack.utils import OPENSTACK_CODENAMES
|
|
|
|
try:
|
|
from jinja2 import FileSystemLoader, ChoiceLoader, Environment, exceptions
|
|
except ImportError:
|
|
apt_update(fatal=True)
|
|
if six.PY2:
|
|
apt_install('python-jinja2', fatal=True)
|
|
else:
|
|
apt_install('python3-jinja2', fatal=True)
|
|
from jinja2 import FileSystemLoader, ChoiceLoader, Environment, exceptions
|
|
|
|
|
|
class OSConfigException(Exception):
|
|
pass
|
|
|
|
|
|
def get_loader(templates_dir, os_release):
|
|
"""
|
|
Create a jinja2.ChoiceLoader containing template dirs up to
|
|
and including os_release. If directory template directory
|
|
is missing at templates_dir, it will be omitted from the loader.
|
|
templates_dir is added to the bottom of the search list as a base
|
|
loading dir.
|
|
|
|
A charm may also ship a templates dir with this module
|
|
and it will be appended to the bottom of the search list, eg::
|
|
|
|
hooks/charmhelpers/contrib/openstack/templates
|
|
|
|
:param templates_dir (str): Base template directory containing release
|
|
sub-directories.
|
|
:param os_release (str): OpenStack release codename to construct template
|
|
loader.
|
|
:returns: jinja2.ChoiceLoader constructed with a list of
|
|
jinja2.FilesystemLoaders, ordered in descending
|
|
order by OpenStack release.
|
|
"""
|
|
tmpl_dirs = [(rel, os.path.join(templates_dir, rel))
|
|
for rel in six.itervalues(OPENSTACK_CODENAMES)]
|
|
|
|
if not os.path.isdir(templates_dir):
|
|
log('Templates directory not found @ %s.' % templates_dir,
|
|
level=ERROR)
|
|
raise OSConfigException
|
|
|
|
# the bottom contains tempaltes_dir and possibly a common templates dir
|
|
# shipped with the helper.
|
|
loaders = [FileSystemLoader(templates_dir)]
|
|
helper_templates = os.path.join(os.path.dirname(__file__), 'templates')
|
|
if os.path.isdir(helper_templates):
|
|
loaders.append(FileSystemLoader(helper_templates))
|
|
|
|
for rel, tmpl_dir in tmpl_dirs:
|
|
if os.path.isdir(tmpl_dir):
|
|
loaders.insert(0, FileSystemLoader(tmpl_dir))
|
|
if rel == os_release:
|
|
break
|
|
# demote this log to the lowest level; we don't really need to see these
|
|
# lots in production even when debugging.
|
|
log('Creating choice loader with dirs: %s' %
|
|
[l.searchpath for l in loaders], level=TRACE)
|
|
return ChoiceLoader(loaders)
|
|
|
|
|
|
class OSConfigTemplate(object):
|
|
"""
|
|
Associates a config file template with a list of context generators.
|
|
Responsible for constructing a template context based on those generators.
|
|
"""
|
|
|
|
def __init__(self, config_file, contexts, config_template=None):
|
|
self.config_file = config_file
|
|
|
|
if hasattr(contexts, '__call__'):
|
|
self.contexts = [contexts]
|
|
else:
|
|
self.contexts = contexts
|
|
|
|
self._complete_contexts = []
|
|
|
|
self.config_template = config_template
|
|
|
|
def context(self):
|
|
ctxt = {}
|
|
for context in self.contexts:
|
|
_ctxt = context()
|
|
if _ctxt:
|
|
ctxt.update(_ctxt)
|
|
# track interfaces for every complete context.
|
|
[self._complete_contexts.append(interface)
|
|
for interface in context.interfaces
|
|
if interface not in self._complete_contexts]
|
|
return ctxt
|
|
|
|
def complete_contexts(self):
|
|
'''
|
|
Return a list of interfaces that have satisfied contexts.
|
|
'''
|
|
if self._complete_contexts:
|
|
return self._complete_contexts
|
|
self.context()
|
|
return self._complete_contexts
|
|
|
|
@property
|
|
def is_string_template(self):
|
|
""":returns: Boolean if this instance is a template initialised with a string"""
|
|
return self.config_template is not None
|
|
|
|
|
|
class OSConfigRenderer(object):
|
|
"""
|
|
This class provides a common templating system to be used by OpenStack
|
|
charms. It is intended to help charms share common code and templates,
|
|
and ease the burden of managing config templates across multiple OpenStack
|
|
releases.
|
|
|
|
Basic usage::
|
|
|
|
# import some common context generates from charmhelpers
|
|
from charmhelpers.contrib.openstack import context
|
|
|
|
# Create a renderer object for a specific OS release.
|
|
configs = OSConfigRenderer(templates_dir='/tmp/templates',
|
|
openstack_release='folsom')
|
|
# register some config files with context generators.
|
|
configs.register(config_file='/etc/nova/nova.conf',
|
|
contexts=[context.SharedDBContext(),
|
|
context.AMQPContext()])
|
|
configs.register(config_file='/etc/nova/api-paste.ini',
|
|
contexts=[context.IdentityServiceContext()])
|
|
configs.register(config_file='/etc/haproxy/haproxy.conf',
|
|
contexts=[context.HAProxyContext()])
|
|
configs.register(config_file='/etc/keystone/policy.d/extra.cfg',
|
|
contexts=[context.ExtraPolicyContext()
|
|
context.KeystoneContext()],
|
|
config_template=hookenv.config('extra-policy'))
|
|
# write out a single config
|
|
configs.write('/etc/nova/nova.conf')
|
|
# write out all registered configs
|
|
configs.write_all()
|
|
|
|
**OpenStack Releases and template loading**
|
|
|
|
When the object is instantiated, it is associated with a specific OS
|
|
release. This dictates how the template loader will be constructed.
|
|
|
|
The constructed loader attempts to load the template from several places
|
|
in the following order:
|
|
- from the most recent OS release-specific template dir (if one exists)
|
|
- the base templates_dir
|
|
- a template directory shipped in the charm with this helper file.
|
|
|
|
For the example above, '/tmp/templates' contains the following structure::
|
|
|
|
/tmp/templates/nova.conf
|
|
/tmp/templates/api-paste.ini
|
|
/tmp/templates/grizzly/api-paste.ini
|
|
/tmp/templates/havana/api-paste.ini
|
|
|
|
Since it was registered with the grizzly release, it first searches
|
|
the grizzly directory for nova.conf, then the templates dir.
|
|
|
|
When writing api-paste.ini, it will find the template in the grizzly
|
|
directory.
|
|
|
|
If the object were created with folsom, it would fall back to the
|
|
base templates dir for its api-paste.ini template.
|
|
|
|
This system should help manage changes in config files through
|
|
openstack releases, allowing charms to fall back to the most recently
|
|
updated config template for a given release
|
|
|
|
The haproxy.conf, since it is not shipped in the templates dir, will
|
|
be loaded from the module directory's template directory, eg
|
|
$CHARM/hooks/charmhelpers/contrib/openstack/templates. This allows
|
|
us to ship common templates (haproxy, apache) with the helpers.
|
|
|
|
**Context generators**
|
|
|
|
Context generators are used to generate template contexts during hook
|
|
execution. Doing so may require inspecting service relations, charm
|
|
config, etc. When registered, a config file is associated with a list
|
|
of generators. When a template is rendered and written, all context
|
|
generates are called in a chain to generate the context dictionary
|
|
passed to the jinja2 template. See context.py for more info.
|
|
"""
|
|
def __init__(self, templates_dir, openstack_release):
|
|
if not os.path.isdir(templates_dir):
|
|
log('Could not locate templates dir %s' % templates_dir,
|
|
level=ERROR)
|
|
raise OSConfigException
|
|
|
|
self.templates_dir = templates_dir
|
|
self.openstack_release = openstack_release
|
|
self.templates = {}
|
|
self._tmpl_env = None
|
|
|
|
if None in [Environment, ChoiceLoader, FileSystemLoader]:
|
|
# if this code is running, the object is created pre-install hook.
|
|
# jinja2 shouldn't get touched until the module is reloaded on next
|
|
# hook execution, with proper jinja2 bits successfully imported.
|
|
if six.PY2:
|
|
apt_install('python-jinja2')
|
|
else:
|
|
apt_install('python3-jinja2')
|
|
|
|
def register(self, config_file, contexts, config_template=None):
|
|
"""
|
|
Register a config file with a list of context generators to be called
|
|
during rendering.
|
|
config_template can be used to load a template from a string instead of
|
|
using template loaders and template files.
|
|
:param config_file (str): a path where a config file will be rendered
|
|
:param contexts (list): a list of context dictionaries with kv pairs
|
|
:param config_template (str): an optional template string to use
|
|
"""
|
|
self.templates[config_file] = OSConfigTemplate(
|
|
config_file=config_file,
|
|
contexts=contexts,
|
|
config_template=config_template
|
|
)
|
|
log('Registered config file: {}'.format(config_file),
|
|
level=INFO)
|
|
|
|
def _get_tmpl_env(self):
|
|
if not self._tmpl_env:
|
|
loader = get_loader(self.templates_dir, self.openstack_release)
|
|
self._tmpl_env = Environment(loader=loader)
|
|
|
|
def _get_template(self, template):
|
|
self._get_tmpl_env()
|
|
template = self._tmpl_env.get_template(template)
|
|
log('Loaded template from {}'.format(template.filename),
|
|
level=INFO)
|
|
return template
|
|
|
|
def _get_template_from_string(self, ostmpl):
|
|
'''
|
|
Get a jinja2 template object from a string.
|
|
:param ostmpl: OSConfigTemplate to use as a data source.
|
|
'''
|
|
self._get_tmpl_env()
|
|
template = self._tmpl_env.from_string(ostmpl.config_template)
|
|
log('Loaded a template from a string for {}'.format(
|
|
ostmpl.config_file),
|
|
level=INFO)
|
|
return template
|
|
|
|
def render(self, config_file):
|
|
if config_file not in self.templates:
|
|
log('Config not registered: {}'.format(config_file), level=ERROR)
|
|
raise OSConfigException
|
|
|
|
ostmpl = self.templates[config_file]
|
|
ctxt = ostmpl.context()
|
|
|
|
if ostmpl.is_string_template:
|
|
template = self._get_template_from_string(ostmpl)
|
|
log('Rendering from a string template: '
|
|
'{}'.format(config_file),
|
|
level=INFO)
|
|
else:
|
|
_tmpl = os.path.basename(config_file)
|
|
try:
|
|
template = self._get_template(_tmpl)
|
|
except exceptions.TemplateNotFound:
|
|
# if no template is found with basename, try looking
|
|
# for it using a munged full path, eg:
|
|
# /etc/apache2/apache2.conf -> etc_apache2_apache2.conf
|
|
_tmpl = '_'.join(config_file.split('/')[1:])
|
|
try:
|
|
template = self._get_template(_tmpl)
|
|
except exceptions.TemplateNotFound as e:
|
|
log('Could not load template from {} by {} or {}.'
|
|
''.format(
|
|
self.templates_dir,
|
|
os.path.basename(config_file),
|
|
_tmpl
|
|
),
|
|
level=ERROR)
|
|
raise e
|
|
|
|
log('Rendering from template: {}'.format(config_file),
|
|
level=INFO)
|
|
return template.render(ctxt)
|
|
|
|
def write(self, config_file):
|
|
"""
|
|
Write a single config file, raises if config file is not registered.
|
|
"""
|
|
if config_file not in self.templates:
|
|
log('Config not registered: %s' % config_file, level=ERROR)
|
|
raise OSConfigException
|
|
|
|
_out = self.render(config_file)
|
|
if six.PY3:
|
|
_out = _out.encode('UTF-8')
|
|
|
|
with open(config_file, 'wb') as out:
|
|
out.write(_out)
|
|
|
|
log('Wrote template %s.' % config_file, level=INFO)
|
|
|
|
def write_all(self):
|
|
"""
|
|
Write out all registered config files.
|
|
"""
|
|
[self.write(k) for k in six.iterkeys(self.templates)]
|
|
|
|
def set_release(self, openstack_release):
|
|
"""
|
|
Resets the template environment and generates a new template loader
|
|
based on a the new openstack release.
|
|
"""
|
|
self._tmpl_env = None
|
|
self.openstack_release = openstack_release
|
|
self._get_tmpl_env()
|
|
|
|
def complete_contexts(self):
|
|
'''
|
|
Returns a list of context interfaces that yield a complete context.
|
|
'''
|
|
interfaces = []
|
|
[interfaces.extend(i.complete_contexts())
|
|
for i in six.itervalues(self.templates)]
|
|
return interfaces
|
|
|
|
def get_incomplete_context_data(self, interfaces):
|
|
'''
|
|
Return dictionary of relation status of interfaces and any missing
|
|
required context data. Example:
|
|
{'amqp': {'missing_data': ['rabbitmq_password'], 'related': True},
|
|
'zeromq-configuration': {'related': False}}
|
|
'''
|
|
incomplete_context_data = {}
|
|
|
|
for i in six.itervalues(self.templates):
|
|
for context in i.contexts:
|
|
for interface in interfaces:
|
|
related = False
|
|
if interface in context.interfaces:
|
|
related = context.get_related()
|
|
missing_data = context.missing_data
|
|
if missing_data:
|
|
incomplete_context_data[interface] = {'missing_data': missing_data}
|
|
if related:
|
|
if incomplete_context_data.get(interface):
|
|
incomplete_context_data[interface].update({'related': True})
|
|
else:
|
|
incomplete_context_data[interface] = {'related': True}
|
|
else:
|
|
incomplete_context_data[interface] = {'related': False}
|
|
return incomplete_context_data
|