The context Module

Utilities to create context and configuration objects

class Cardinality(value)

Cardinality of a configuration parameter: multiple or singular

single = 'single'

multiple = 'multiple'

class Argument(name, help: str, type=<class 'str'>, aliases: ~typing.Optional[~typing.List] = None, default=None, cardinality: ~nsaph_utils.utils.context.Cardinality = Cardinality.single, valid_values=None, required=True)

A wrapper class to describe a command-line arguments This is practically, a more rigid format for :func ArgumentParser.add_argument:

All arguments are passed to Argparser

Parameters

• name –

• help –

• type –

• aliases –

• default –

• cardinality –

• valid_values –

get_action()

get_nargs()

get_help()

is_required()

add_to(parser)

class Context(subclass, description=None, include_default: bool = True)

Generic class allowing to build context and configuration objects and initialize them using command line arguments

Creates a new object

Parameters

• subclass – A concrete class containing configuration information Configuration options must be defined as class memebers with names, starting with one ‘_’ characters and values be instances of :class Argument:

• description – Optional text to use as description. If not specified, then it is extracted from subclass documentation

years

Year or list of years to download. For example, the following argument: -y 1992:1995 1998 1999 2011 2015:2017 will produce the following list: [1992,1993,1994,1995,1998,1999,2011,2015,2016,2017]

compress

Specifies whether to use gzip compression for the result

instantiate()

set_empty_args()

default()

validate(attr, value)

Subclasses can override this method to implement custom handling of command line arguments

Parameters

• attr – Command line argument name

• value – Value returned by argparse

Returns

value to use

classmethod enum(enum_cls, s: str)

A helper method to return Enum value by its name

Parameters

• cls – Enum class

• s – name of a member in Enum class

Returns

value of the member