Source code for nemo_nowcast.cli

# Copyright 2016-2021 Doug Latornell, 43ravens

# 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


# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# See the License for the specific language governing permissions and
# limitations under the License.

"""NEMO_Nowcast framework command-line interface.

Provides a command-line interface argument parser for nowcast system components.
The parser includes handling for the always-required :kbd:`config_file`
import argparse

import arrow
import attr

[docs]@attr.s class CommandLineInterface: """Construct a :py:class:`nemo_nowcast.cli.CommandLineInterface` instance. """ #: Name of the module that the parser is for; #: used to build the usage message. module_name = attr.ib() #: Name of the package that the module is part of; #: used to build the usage message. #: Use dotted notation; e.g. :kbd:`nowcast.workers`. package = attr.ib(default="nowcast") #: Brief description of what the module does that will be displayed in the #: help messages. description = attr.ib(default=None) #: Argument parser; created by calling the #: :py:meth:`~nemo_nowcast.cli.CommandLineInterface.build_parser` method. parser = attr.ib(default=None, init=False)
[docs] def build_parser(self, add_help=True): """Return a command-line argument parser with its description and usage messages set, and :kbd:`config_file` as a required argument. :arg boolean add_help: Add a `-h/--help` option to the parser. Disable this if you are going to use the returned parser as a parent parser to facilitate adding more args/options. :return: :class:`argparse.ArgumentParser` object """ self.parser = argparse.ArgumentParser( description=self.description, add_help=add_help ) self.parser.prog = f"python -m {self.package}.{self.module_name}" self.parser.add_argument( "config_file", help="Path/name of YAML configuration file for NEMO nowcast." )
[docs] def add_argument(self, *args, **kwargs): """Add an argument to the CLI parser. This is a thin wrapper around :py:meth:`argparse.ArgumentParser.add_argument` that accepts that method's arguments. """ self.parser.add_argument(*args, **kwargs)
[docs] def add_date_option(self, name, default, help): """Add a date option to the CLI parser. The stored date is an :py:class:`arrow.Arrow` object. This is a thin wrapper around :py:meth:`argparse.ArgumentParser.add_argument` that sets the type of the option to :py:meth:`nemo_nowcast.cli.CommandLineInterface.arrow_date`, and append information about the option's format and default value to the *help* message. :arg str name: Option name/flag; e.g. :kbd:`--forecast-date`. :arg default: Date to use when the option is not included on the command-line; typically :kbd:`'day')`. :type default: :py:class:`arrow.Arrow` :arg str help: Help message. The words "Use YYYY-MM-DD format. Defaults to {default}." are appended to the message provided, where "{default}" is the value of *default* formatted as :kbd:`YYYY-MM-DD`. """ self.parser.add_argument( name, type=self.arrow_date, default=default, help=( f"{help} Use YYYY-MM-DD format. Defaults to {default.format('YYYY-MM-DD')}." ), )
[docs] @staticmethod def arrow_date(string): """Convert a YYYY-MM-DD string to a UTC arrow object or raise :py:exc:`argparse.ArgumentTypeError`. The time part of the resulting arrow object is set to 00:00:00. :arg str string: YYYY-MM-DD string to convert. :returns: Date string converted to a UTC :py:class:`arrow.Arrow` object. :raises: :py:exc:`argparse.ArgumentTypeError` """ try: return arrow.get(string, "YYYY-MM-DD") except arrow.parser.ParserError: msg = f"unrecognized date format: {string} - please use YYYY-MM-DD" raise argparse.ArgumentTypeError(msg)