class django_docker_helpers.config.ConfigLoader(parsers, silent=False, suppress_logs=False, keep_read_records_max=1024)[source]
  • provides a single interface to read from specified config parsers in order they present;

  • tracks accessed from parsers options;

  • prints config options access log in pretty-print way.


env = {
    'PROJECT__DEBUG': 'false'
parsers = [
    EnvironmentParser(scope='project', env=env),
    RedisParser('my/conf/service/config.yml', host=REDIS_HOST, port=REDIS_PORT),
    YamlParser(config='./tests/data/config.yml', scope='project'),
configure = ConfigLoader(parsers=parsers)

DEBUG = configure('debug')  # 'false'
DEBUG = configure('debug', coerce_type=bool)  # False
  • takes a list of initialized parsers;

  • it’s supposed to use ONLY unique parsers for parsers argument (or you are going to get the same initial arguments for all parsers of the same type in from_env());

  • the parsers’s order does matter.

  • parsers (List[BaseParser]) – a list of initialized parsers

  • silent (bool) – don’t raise exceptions if any read attempt failed

  • suppress_logs (bool) – don’t display any exception warnings on screen

  • keep_read_records_max (int) – max capacity queue length

format_config_read_queue(use_color=False, max_col_width=50)[source]

Prepares a string with pretty printed config read queue.

  • use_color (bool) – use terminal colors

  • max_col_width (int) – limit column width, 50 by default

Return type



static from_env(parser_modules=('django_docker_helpers.config.backends.EnvironmentParser', 'django_docker_helpers.config.backends.MPTRedisParser', 'django_docker_helpers.config.backends.MPTConsulParser', 'django_docker_helpers.config.backends.RedisParser', 'django_docker_helpers.config.backends.ConsulParser', 'django_docker_helpers.config.backends.YamlParser'), env=None, silent=False, suppress_logs=False, extra=None)[source]

Creates an instance of ConfigLoader with parsers initialized from environment variables.

By default it tries to initialize all bundled parsers. Parsers may be customized with parser_modules argument or CONFIG__PARSERS environment variable. Environment variable has a priority over the method argument.

  • parser_modules (Union[List[str], Tuple[str], None]) – a list of dot-separated module paths

  • env (Optional[Dict[str, str]]) – a dict with environment variables, default is os.environ

  • silent (bool) – passed to ConfigLoader

  • suppress_logs (bool) – passed to ConfigLoader

  • extra (Optional[dict]) – pass extra arguments to every parser

Return type



an instance of ConfigLoader


env = {
    'CONFIG__PARSERS': 'EnvironmentParser,RedisParser,YamlParser',
    'YAMLPARSER__CONFIG': './tests/data/config.yml',
    'REDISPARSER__HOST': 'wtf.test',
    'NESTED__VARIABLE': 'i_am_here',

loader = ConfigLoader.from_env(env=env)
assert [type(p) for p in loader.parsers] == [EnvironmentParser, RedisParser, YamlParser]
assert loader.get('variable') == 'i_am_here', 'Ensure env copied from ConfigLoader'

loader = ConfigLoader.from_env(parser_modules=['EnvironmentParser'], env={})
get(variable_path, default=None, coerce_type=None, coercer=None, required=False, **kwargs)[source]

Tries to read a variable_path from each of the passed parsers. It stops if read was successful and returns a retrieved value. If none of the parsers contain a value for the specified path it returns default.

  • variable_path (str) – a path to variable in config

  • default (Optional[Any]) – a default value if variable_path is not present anywhere

  • coerce_type (Optional[Type]) – cast a result to a specified type

  • coercer (Optional[Callable]) – perform the type casting with specified callback

  • required (bool) – raise RequiredValueIsEmpty if no default and no result

  • kwargs – additional options to all parsers


the first successfully read value from the list of parser instances or default


config.exceptions.RequiredValueIsEmpty – if nothing is read,``required`` flag is set, and there’s no default specified

static import_parsers(parser_modules)[source]

Resolves and imports all modules specified in parser_modules. Short names from the local scope are supported (the scope is django_docker_helpers.config.backends).


parser_modules (Iterable[str]) – a list of dot-separated module paths

Return type

Generator[Type[BaseParser], None, None]


a generator of [probably] BaseParser


parsers = list(ConfigLoader.import_parsers([
assert parsers == [EnvironmentParser, YamlParser]
static load_parser_options_from_env(parser_class, env=None)[source]

Extracts arguments from parser_class.__init__ and populates them from environment variables.

Uses __init__ argument type annotations for correct type casting.


Environment variables should be prefixed with <UPPERCASEPARSERCLASSNAME>__.

  • parser_class (Type[BaseParser]) – a subclass of BaseParser

  • env (Optional[Dict[str, str]]) – a dict with environment variables, default is os.environ

Return type

Dict[str, Any]


parser’s __init__ arguments dict mapping


env = {
    'REDISPARSER__ENDPOINT': 'go.deep',
    'REDISPARSER__HOST': 'my-host',
    'REDISPARSER__PORT': '66',

res = ConfigLoader.load_parser_options_from_env(RedisParser, env)
assert res == {'endpoint': 'go.deep', 'host': 'my-host', 'port': 66}
print_config_read_queue(use_color=False, max_col_width=50)[source]

Prints all read (in call order) options.

  • max_col_width (int) – limit column width, 50 by default

  • use_color (bool) – use terminal colors



class django_docker_helpers.config.ConfigReadItem(variable_path, value, type, is_default, parser_name)

Create new instance of ConfigReadItem(variable_path, value, type, is_default, parser_name)

property is_default

Alias for field number 3

property parser_name

Alias for field number 4

property type

Alias for field number 2

property value

Alias for field number 1

property variable_path

Alias for field number 0