ArgParser

ArgParser is designed for processing command-line arguments passed to the application at startup. It’s important not to confuse them with flags that the user enters in interactive mode. ArgParser allows receiving external configuration at startup (e.g., path to settings file, debug flags, or launch mode).

Initialization

1def __init__(self, processed_args: list[ValueArgument | BooleanArgument], *,
2             name: str = "Argenta",
3             description: str = "Argenta available arguments",
4             epilog: str = "github.com/koloideal/Argenta | made by kolo")

Creates an instance of the command-line argument parser.

  • processed_args: List of arguments to process at application startup. For more details, see here.

  • name: Application name for display in help.

  • description: Application description for display in help.

  • epilog: Additional information for display at the end of help.

Attributes

parsed_argspace: ArgSpace

ArgSpace instance containing all processed command-line arguments. For more details, see here.

Caution

Before initializing Orchestrator, to whose constructor an ArgParser instance was passed, the parsed_argspace attribute will contain an empty ArgSpace.

Parsing and validation of arguments occur during Orchestrator initialization, so using parsed_argspace is advisable only after that.

Best Practices

Using the parsed_argspace attribute is recommended only during the application setup phase. In handlers, the best practice is to obtain ArgSpace through DI. For more details, see here.

Usage example:

 1from argenta import App, Orchestrator
 2from argenta.orchestrator.argparser import ArgParser, BooleanArgument
 3
 4arg_parser = ArgParser(
 5    processed_args=[
 6        BooleanArgument("dev")
 7    ]
 8)
 9orchestrator = Orchestrator(
10    arg_parser=arg_parser,
11)
12
13if __name__ == "__main__":
14    if arg_parser.parsed_argspace.get_by_name("dev"):
15        orchestrator.start_polling(App(initial_message="ArgentaDev"))
16    else:
17        orchestrator.start_polling(App())

Error Handling

See also

For more details on argument types, see Arguments

When working with command-line arguments, the standard ArgumentParser automatically handles the following situations:

Missing required argument:

$ python app.py
usage: Argenta [-h] --config CONFIG
Argenta: error: the following arguments are required: --config

Invalid value from possible_values list:

$ python app.py --config app.yaml --log-level TRACE
usage: Argenta [-h] --log-level {DEBUG,INFO,WARNING,ERROR,CRITICAL}
Argenta: error: argument --log-level: invalid choice: 'TRACE'

Using a deprecated argument:

When using an argument with is_deprecated=True, a warning is displayed, but execution continues:

$ python app.py --old-param value
Warning: argument --old-param is deprecated

Warning

Параметр поддерживается начиная с версии CPython 3.13, если версия ниже, то параметр будет игнорироваться.