armada/armada/handlers/chartbuilder.py

286 lines
10 KiB
Python

# Copyright 2017 The Armada Authors.
#
# 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 yaml
from google.protobuf.any_pb2 import Any
from hapi.chart.chart_pb2 import Chart
from hapi.chart.config_pb2 import Config
from hapi.chart.metadata_pb2 import Metadata
from hapi.chart.template_pb2 import Template
from supermutes.dot import dotify
from oslo_config import cfg
from oslo_log import log as logging
from armada.exceptions import chartbuilder_exceptions
LOG = logging.getLogger(__name__)
CONF = cfg.CONF
class ChartBuilder(object):
'''
This class handles taking chart intentions as a parameter and
turning those into proper protoc helm charts that can be
pushed to tiller.
It also processes chart source declarations, fetching chart
source from external resources where necessary
'''
def __init__(self, chart, parent=None):
'''
Initialize the ChartBuilder class
Note that tthis will trigger a source pull as part of
initialization as its necessary in order to examine
the source service many of the calls on ChartBuilder
'''
# cache for generated protoc chart object
self._helm_chart = None
# record whether this is a dependency based chart
self.parent = parent
# store chart schema
self.chart = chart
# extract, pull, whatever the chart from its source
self.source_directory = self.get_source_path()
# load ignored files from .helmignore if present
self.ignored_files = self.get_ignored_files()
def get_source_path(self):
'''
Return the joined path of the source directory and subpath
'''
return (
os.path.join(self.chart.source_dir[0], self.chart.source_dir[1])
if (hasattr(self.chart, 'source_dir') and
isinstance(self.chart.source_dir, (list, tuple)) and
len(self.chart.source_dir) == 2)
else ""
)
def get_ignored_files(self):
'''
Load files from .helmignore if present
'''
try:
ignored_files = []
if os.path.exists(os.path.join(self.source_directory,
'.helmignore')):
with open(os.path.join(self.source_directory,
'.helmignore')) as f:
ignored_files = f.readlines()
return [filename.strip() for filename in ignored_files]
except Exception:
raise chartbuilder_exceptions.IgnoredFilesLoadException()
def ignore_file(self, filename):
'''
:params file - filename to compare against list of ignored files
Returns true if file matches an ignored file wildcard or exact name,
false otherwise
'''
for ignored_file in self.ignored_files:
if (ignored_file.startswith('*') and
filename.endswith(ignored_file.strip('*'))):
return True
elif ignored_file == filename:
return True
return False
def get_metadata(self):
'''
Process metadata
'''
# extract Chart.yaml to construct metadata
try:
with open(os.path.join(self.source_directory, 'Chart.yaml')) as f:
chart_yaml = dotify(yaml.safe_load(f.read().encode('utf-8')))
except Exception:
raise chartbuilder_exceptions.MetadataLoadException()
# construct Metadata object
return Metadata(
description=chart_yaml.description,
name=chart_yaml.name,
version=chart_yaml.version)
def get_files(self):
'''
Return (non-template) files in this chart.
Non-template files include all files *except* Chart.yaml, values.yaml,
values.toml, and any file nested under charts/ or templates/. The only
exception to this rule is charts/.prov
The class :class:`google.protobuf.any_pb2.Any` is wrapped around
each file as that is what Helm uses.
For more information, see:
https://github.com/kubernetes/helm/blob/fa06dd176dbbc247b40950e38c09f978efecaecc/pkg/chartutil/load.go
:returns: List of non-template files.
:rtype: List[:class:`google.protobuf.any_pb2.Any`]
'''
files_to_ignore = ['Chart.yaml', 'values.yaml', 'values.toml']
non_template_files = []
def _append_file_to_result(root, rel_folder_path, file):
abspath = os.path.abspath(os.path.join(root, file))
relpath = os.path.join(rel_folder_path, file)
encodings = ('utf-8', 'latin1')
unicode_errors = []
for encoding in encodings:
try:
with open(abspath, 'r') as f:
file_contents = f.read().encode(encoding)
except OSError as e:
LOG.debug('Failed to open and read file %s in the helm '
'chart directory.', abspath)
raise chartbuilder_exceptions.FilesLoadException(
file=abspath, details=e)
except UnicodeError as e:
LOG.debug('Attempting to read %s using encoding %s.',
abspath, encoding)
msg = "(encoding=%s) %s" % (encoding, str(e))
unicode_errors.append(msg)
else:
break
if len(unicode_errors) == 2:
LOG.debug('Failed to read file %s in the helm chart directory.'
' Ensure that it is encoded using utf-8.', abspath)
raise chartbuilder_exceptions.FilesLoadException(
file=abspath, clazz=unicode_errors[0].__class__.__name__,
details='\n'.join(e for e in unicode_errors))
non_template_files.append(
Any(type_url=relpath,
value=file_contents))
for root, dirs, files in os.walk(self.source_directory):
relfolder = os.path.split(root)[-1]
rel_folder_path = os.path.relpath(root, self.source_directory)
if not any(root.startswith(os.path.join(self.source_directory, x))
for x in ['templates', 'charts']):
for file in files:
if (file not in files_to_ignore and
file not in non_template_files):
_append_file_to_result(root, rel_folder_path, file)
elif relfolder == 'charts' and '.prov' in files:
_append_file_to_result(root, rel_folder_path, '.prov')
return non_template_files
def get_values(self):
'''
Return the chart (default) values
'''
# create config object representing unmarshaled values.yaml
if os.path.exists(os.path.join(self.source_directory, 'values.yaml')):
with open(os.path.join(self.source_directory, 'values.yaml')) as f:
raw_values = f.read()
else:
LOG.warn("No values.yaml in %s, using empty values",
self.source_directory)
raw_values = ''
return Config(raw=raw_values)
def get_templates(self):
'''
Return all the chart templates
'''
# process all files in templates/ as a template to attach to the chart
# building a Template object
templates = []
if not os.path.exists(
os.path.join(self.source_directory, 'templates')):
LOG.warn("Chart %s has no templates directory. "
"No templates will be deployed", self.chart.chart_name)
for root, _, files in os.walk(
os.path.join(self.source_directory, 'templates'),
topdown=True):
for tpl_file in files:
tname = os.path.relpath(
os.path.join(root, tpl_file),
os.path.join(self.source_directory, 'templates'))
if self.ignore_file(tname):
LOG.debug('Ignoring file %s', tname)
continue
with open(os.path.join(root, tpl_file)) as f:
templates.append(
Template(name=tname, data=f.read().encode()))
return templates
def get_helm_chart(self):
'''
Return a helm chart object
'''
if self._helm_chart:
return self._helm_chart
dependencies = []
for dep in self.chart.dependencies:
LOG.info("Building dependency chart %s for release %s.",
dep.chart.chart_name, self.chart.release)
try:
dependencies.append(ChartBuilder(dep.chart).get_helm_chart())
except Exception:
chart_name = self.chart.chart_name
raise chartbuilder_exceptions.DependencyException(chart_name)
try:
helm_chart = Chart(
metadata=self.get_metadata(),
templates=self.get_templates(),
dependencies=dependencies,
values=self.get_values(),
files=self.get_files())
except Exception as e:
chart_name = self.chart.chart_name
raise chartbuilder_exceptions.HelmChartBuildException(
chart_name, details=e)
self._helm_chart = helm_chart
return helm_chart
def dump(self):
'''
This method is used to dump a chart object as a
serialized string so that we can perform a diff
It should recurse into dependencies
'''
return self.get_helm_chart().SerializeToString()