CommandParser

Customized ArgumentParser class to improve some error messages and prevent SystemExit in several occasions, as SystemExit is unacceptable when a command is called programmatically.

Attributes

Attribute	Type	Description
missing_args_message	string	Custom error message displayed when required arguments are missing during parsing.
called_from_command_line	boolean	Boolean flag determining if errors should trigger a SystemExit or raise a CommandError exception.

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Constructor

Signature

def CommandParser(
    missing_args_message: string = None,
    called_from_command_line: boolean = None,
    **kwargs: dict
) - > null

Parameters

Name	Type	Description
missing_args_message	string = None	Custom message to display when required arguments are missing.
called_from_command_line	boolean = None	Flag indicating if the parser was invoked via the CLI to determine error handling behavior.
**kwargs	dict	Arbitrary keyword arguments passed to the parent ArgumentParser class.

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Signature

def CommandParser(
    missing_args_message: string = null,
    called_from_command_line: boolean = null,
    **kwargs: dict
) - > null

Parameters

Name	Type	Description
missing_args_message	string = null	The custom error message to display when required arguments are not provided
called_from_command_line	boolean = null	A flag indicating if the parser was invoked via the CLI, determining whether to exit or raise a CommandError
**kwargs	dict	Additional keyword arguments passed to the parent ArgumentParser constructor

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Methods

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parse_args()

@classmethod
def parse_args(
    args: list = null,
    namespace: object = null
) - > Namespace

Parses the provided argument strings into a namespace object while validating for missing required arguments.

Parameters

Name	Type	Description
args	list = null	A list of strings representing the command-line arguments to parse
namespace	object = null	An existing object to populate with attributes instead of creating a new Namespace

Returns

Type	Description
Namespace	An object containing the populated attributes from the parsed command-line arguments

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error()

@classmethod
def error(
    message: string
) - > null

Handles parsing errors by either calling the system error handler or raising a CommandError depending on the execution context.

Parameters

Name	Type	Description
message	string	The error message describing the parsing failure

Returns

Type	Description
null	None

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add_subparsers()

@classmethod
def add_subparsers(
    **kwargs: dict
) - > _SubParsersAction

Adds a sub-command parser to the current parser, ensuring child parsers inherit the execution context and class type.

Parameters

Name	Type	Description
**kwargs	dict	Keyword arguments for sub-parser configuration, including the parser_class to use for sub-commands

Returns

Type	Description
_SubParsersAction	An action object that allows adding specific sub-commands to the parser

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