async2v.cli module¶

Build a command-line interface for your application.

Subclass ApplicationLauncher and override the required methods to configure your components and run your application without having to write boilerplate.

This gives you the predefined commands run, graph and possibly additional commands provided by component configurators. In addition, you can also define additional commands by subclassing Command and add them to your application by registering a subclass of Configurator.

Summary¶

Classes:

`ApplicationLauncher`	Main entry point for a async2v commandline application.
`Command`	Abstract base class to define subcommands for the command line interface
`Configurator`	Abstract base class to define reusable command line arguments and configuration parsers

Reference¶

class Command¶

Bases: object

Abstract base class to define subcommands for the command line interface

__call__(args, app=None)¶

Override to define the command logic.

Parameters:	args – Arguments parsed by argparse app (`Optional`[`Application`]) – Holds an `Application` instance if `needs_app` is `True`, otherwise `None`
Return type:	`None`

name¶

Name of the subcommand

Return type:	`str`

help¶

Help text used in the command line interface

Return type:	`str`

needs_app¶

Return True if your command requires a fully configured Application instance.

Return type:	`bool`

add_arguments(parser)¶

Override to register commandline arguments for this command

Parameters:	parser (`ArgumentParser`) –
Return type:	`None`

class Configurator¶

Bases: object

Abstract base class to define reusable command line arguments and configuration parsers

A configurator can optionally provide one or more subcommands by returning a list of Command instances.

add_app_arguments(parser)¶

Override to register additional parameters for the application.

Parameters:	parser (`ArgumentParser`) –
Return type:	`None`

commands¶

Override to register additional subcommands.

Return type:	`List`[`Command`]

class ApplicationLauncher¶

Bases: object

Main entry point for a async2v commandline application.

To register components, override register_application_components and call app.register(...).
Some components have predefined configurators that can be hooked into the launcher:
- Override __init__ and call self.add_configurator(...) to register them.
- Construct the configuration with MyConfigurator.config_from_args(...) in register_application_components.
Override add_app_arguments to register argparse arguments for your application.

add_configurator(configurator)¶

Add a configurator to be evaluated by argparse.

This method needs to be called from the constructor to be effective.

Parameters:	configurator (`Configurator`) – Configurator provided by a configurable `Component`

add_app_arguments(parser)¶

Override this method to specify arguments that are needed to construct the application, i.e. when register_application_components is called.

Parameters:	parser (`ArgumentParser`) –

register_application_components(args, app)¶

This method must be overridden.

Use app.register(...) to register your components, using the parsed commandline args.

Parameters:	args – Arguments parsed by argparse app (`Application`) –

main(args=None)¶

Launch the commandline interface.

Parameters:	args – Optionally pass arguments. If not given, the arguments passed to the program will be parsed.