This repository has been archived on 2020-03-24. You can view files and clone it, but cannot push or open issues or pull requests.
quay/config_app/config_util/config/baseprovider.py
2019-11-12 11:09:47 -05:00

128 lines
3.8 KiB
Python

import logging
import yaml
from abc import ABCMeta, abstractmethod
from six import add_metaclass
from jsonschema import validate, ValidationError
from util.config.schema import CONFIG_SCHEMA
logger = logging.getLogger(__name__)
class CannotWriteConfigException(Exception):
""" Exception raised when the config cannot be written. """
pass
class SetupIncompleteException(Exception):
""" Exception raised when attempting to verify config that has not yet been setup. """
pass
def import_yaml(config_obj, config_file):
with open(config_file) as f:
c = yaml.safe_load(f)
if not c:
logger.debug('Empty YAML config file')
return
if isinstance(c, str):
raise Exception('Invalid YAML config file: ' + str(c))
for key in c.iterkeys():
if key.isupper():
config_obj[key] = c[key]
if config_obj.get('SETUP_COMPLETE', False):
try:
validate(config_obj, CONFIG_SCHEMA)
except ValidationError:
# TODO: Change this into a real error
logger.exception('Could not validate config schema')
else:
logger.debug('Skipping config schema validation because setup is not complete')
return config_obj
def get_yaml(config_obj):
return yaml.safe_dump(config_obj, encoding='utf-8', allow_unicode=True)
def export_yaml(config_obj, config_file):
try:
with open(config_file, 'w') as f:
f.write(get_yaml(config_obj))
except IOError as ioe:
raise CannotWriteConfigException(str(ioe))
@add_metaclass(ABCMeta)
class BaseProvider(object):
""" A configuration provider helps to load, save, and handle config override in the application.
"""
@property
def provider_id(self):
raise NotImplementedError
@abstractmethod
def update_app_config(self, app_config):
""" Updates the given application config object with the loaded override config. """
@abstractmethod
def get_config(self):
""" Returns the contents of the config override file, or None if none. """
@abstractmethod
def save_config(self, config_object):
""" Updates the contents of the config override file to those given. """
@abstractmethod
def config_exists(self):
""" Returns true if a config override file exists in the config volume. """
@abstractmethod
def volume_exists(self):
""" Returns whether the config override volume exists. """
@abstractmethod
def volume_file_exists(self, filename):
""" Returns whether the file with the given name exists under the config override volume. """
@abstractmethod
def get_volume_file(self, filename, mode='r'):
""" Returns a Python file referring to the given name under the config override volume. """
@abstractmethod
def write_volume_file(self, filename, contents):
""" Writes the given contents to the config override volumne, with the given filename. """
@abstractmethod
def remove_volume_file(self, filename):
""" Removes the config override volume file with the given filename. """
@abstractmethod
def list_volume_directory(self, path):
""" Returns a list of strings representing the names of the files found in the config override
directory under the given path. If the path doesn't exist, returns None.
"""
@abstractmethod
def save_volume_file(self, filename, flask_file):
""" Saves the given flask file to the config override volume, with the given
filename.
"""
@abstractmethod
def requires_restart(self, app_config):
""" If true, the configuration loaded into memory for the app does not match that on disk,
indicating that this container requires a restart.
"""
@abstractmethod
def get_volume_path(self, directory, filename):
""" Helper for constructing file paths, which may differ between providers. For example,
kubernetes can't have subfolders in configmaps """