diff --git a/swh/core/config.py b/swh/core/config.py index 2fdd45e..940adb4 100644 --- a/swh/core/config.py +++ b/swh/core/config.py @@ -1,276 +1,281 @@ # Copyright (C) 2015 The Software Heritage developers # See the AUTHORS file at the top-level directory of this distribution # License: GNU General Public License version 3, or any later version # See top-level LICENSE file for more information import configparser +import logging import os import yaml SWH_CONFIG_DIRECTORIES = [ '~/.config/swh', '~/.swh', '/etc/softwareheritage', ] SWH_GLOBAL_CONFIG = 'global.ini' SWH_DEFAULT_GLOBAL_CONFIG = { 'content_size_limit': ('int', 100 * 1024 * 1024), 'log_db': ('str', 'dbname=softwareheritage-log'), } SWH_CONFIG_EXTENSIONS = [ '.yml', '.ini', ] # conversion per type _map_convert_fn = { 'int': int, 'bool': lambda x: x.lower() == 'true', 'list[str]': lambda x: [value.strip() for value in x.split(',')], 'list[int]': lambda x: [int(value.strip()) for value in x.split(',')], } _map_check_fn = { 'int': lambda x: isinstance(x, int), 'bool': lambda x: isinstance(x, bool), 'list[str]': lambda x: (isinstance(x, list) and all(isinstance(y, str) for y in x)), 'list[int]': lambda x: (isinstance(x, list) and all(isinstance(y, int) for y in x)), } def exists_accessible(file): """Check whether a file exists, and is accessible. Returns: True if the file exists and is accessible False if the file does not exist Raises: PermissionError if the file cannot be read. """ try: os.stat(file) except PermissionError: raise except FileNotFoundError: return False else: if os.access(file, os.R_OK): return True else: raise PermissionError("Permission denied: %r" % file) def config_basepath(config_path): """Return the base path of a configuration file""" if config_path.endswith(('.ini', '.yml')): return config_path[:-4] return config_path def read_raw_config(base_config_path): """Read the raw config corresponding to base_config_path. Can read yml or ini files. """ yml_file = base_config_path + '.yml' if exists_accessible(yml_file): + logging.debug('Using config file %s', yml_file) with open(yml_file) as f: return yaml.safe_load(f) ini_file = base_config_path + '.ini' if exists_accessible(ini_file): config = configparser.ConfigParser() config.read(ini_file) if 'main' in config._sections: + logging.debug('Using config file %s', ini_file) return config._sections['main'] + else: + logging.debug('Ignoring config file %s (no [main])', ini_file) return {} def config_exists(config_path): """Check whether the given config exists""" basepath = config_basepath(config_path) return any(exists_accessible(basepath + extension) for extension in SWH_CONFIG_EXTENSIONS) def read(conf_file=None, default_conf=None): """Read the user's configuration file. Fill in the gap using `default_conf`. `default_conf` is similar to this:: DEFAULT_CONF = { 'a': ('str', '/tmp/swh-loader-git/log'), 'b': ('str', 'dbname=swhloadergit') 'c': ('bool', true) 'e': ('bool', None) 'd': ('int', 10) } If conf_file is None, return the default config. """ conf = {} if conf_file: base_config_path = config_basepath(os.path.expanduser(conf_file)) conf = read_raw_config(base_config_path) if not default_conf: default_conf = {} # remaining missing default configuration key are set # also type conversion is enforced for underneath layer for key in default_conf: nature_type, default_value = default_conf[key] val = conf.get(key, None) if val is None: # fallback to default value conf[key] = default_value elif not _map_check_fn.get(nature_type, lambda x: True)(val): # value present but not in the proper format, force type conversion conf[key] = _map_convert_fn.get(nature_type, lambda x: x)(val) return conf def priority_read(conf_filenames, default_conf=None): """Try reading the configuration files from conf_filenames, in order, and return the configuration from the first one that exists. default_conf has the same specification as it does in read. """ # Try all the files in order for filename in conf_filenames: full_filename = os.path.expanduser(filename) if config_exists(full_filename): return read(full_filename, default_conf) # Else, return the default configuration return read(None, default_conf) def merge_default_configs(base_config, *other_configs): """Merge several default config dictionaries, from left to right""" full_config = base_config.copy() for config in other_configs: full_config.update(config) return full_config def swh_config_paths(base_filename): """Return the Software Heritage specific configuration paths for the given filename.""" return [os.path.join(dirname, base_filename) for dirname in SWH_CONFIG_DIRECTORIES] def prepare_folders(conf, *keys): """Prepare the folder mentioned in config under keys. """ def makedir(folder): if not os.path.exists(folder): os.makedirs(folder) for key in keys: makedir(conf[key]) def load_global_config(): """Load the global Software Heritage config""" return priority_read( swh_config_paths(SWH_GLOBAL_CONFIG), SWH_DEFAULT_GLOBAL_CONFIG, ) def load_named_config(name, default_conf=None, global_conf=True): """Load the config named `name` from the Software Heritage configuration paths. If global_conf is True (default), read the global configuration too. """ conf = {} if global_conf: conf.update(load_global_config()) conf.update(priority_read(swh_config_paths(name), default_conf)) return conf class SWHConfig: """Mixin to add configuration parsing abilities to classes The class should override the class attributes: - DEFAULT_CONFIG (default configuration to be parsed) - CONFIG_BASE_FILENAME (the filename of the configuration to be used) This class defines one classmethod, parse_config_file, which parses a configuration file using the default config as set in the class attribute. """ DEFAULT_CONFIG = {} CONFIG_BASE_FILENAME = '' @classmethod def parse_config_file(cls, base_filename=None, config_filename=None, additional_configs=None, global_config=True): """Parse the configuration file associated to the current class. By default, parse_config_file will load the configuration cls.CONFIG_BASE_FILENAME from one of the Software Heritage configuration directories, in order, unless it is overridden by base_filename or config_filename (which shortcuts the file lookup completely). Args: - base_filename (str) overrides the default cls.CONFIG_BASE_FILENAME - config_filename (str) sets the file to parse instead of the defaults set from cls.CONFIG_BASE_FILENAME - additional_configs (list of default configuration dicts) allows to override or extend the configuration set in cls.DEFAULT_CONFIG. - global_config (bool): Load the global configuration (default: True) """ if config_filename: config_filenames = [config_filename] else: if not base_filename: base_filename = cls.CONFIG_BASE_FILENAME config_filenames = swh_config_paths(base_filename) if not additional_configs: additional_configs = [] full_default_config = merge_default_configs(cls.DEFAULT_CONFIG, *additional_configs) config = {} if global_config: config = load_global_config() config.update(priority_read(config_filenames, full_default_config)) return config