Configuration Options for EPA AirNow Package

Module contains classes to describe the context in which AirNow data is downloaded

class Parameter(value)

An Enum with mnemonic names for the most common EPA AirNow Parameter Codes See more at https://docs.airnowapi.org/Data/docs

NO2 = 'no2'

NO2

OZONE = 'ozone'

ozone

PM25 = 'pm25'

PM25

PM10 = 'pm10'

PM10

CO = 'co'

co

SO2 = 'so2'

SO2

class AirNowContext(doc=None)

This class is part of EPA AirNow Toolkit. It allows user to define any parameters that are used to select what data to download, how to format it and where to place the results.

It is a concrete subclass of :class Context:

Constructor

Parameters

doc – Optional argument, specifying what to print as documentation

parameters

Parameters (variables, e.g. PM25, NO2, etc.) to download

destination

Destination directory for the downloaded files

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

start_date

First date in the range to download (inclusive)

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

end_date

Last date in the range to download (inclusive)

reset

Discard previously downloaded data if exists

qc

Perform basic data QC

cfg

Optional path to config file

shapes

Optional path to shapes directory

api_key

AirNow API Key

proxy

Proxy address

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

Classes used Internally

Abstract Context

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

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

Argument

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 –