liminal/core/util/extensible.py

#
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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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import sys

from liminal.build.image_builder import ImageBuilder
from liminal.core.util import class_util
from liminal.runners.airflow.model import executor
from liminal.runners.airflow.model.task import Task

__PLUGINS = 'plugins'


def __generate_extra_paths(plugin_type, extra_paths):
    return (extra_paths or []) + ([f'{__PLUGINS}.{plugin_type}'] if f'{__PLUGINS}.{plugin_type}' in sys.path else [])


def load_executors(extra_paths=None):
    """
    Load all Executor extensions
    """
    package_paths = ['liminal.runners.airflow.executors'] + __generate_extra_paths('executors', extra_paths)
    return class_util.find_subclasses_in_packages(package_paths, executor.Executor)


def load_tasks(extra_paths=None):
    """
    Load all Task extensions
    """
    package_paths = ['liminal.runners.airflow.tasks'] + __generate_extra_paths('tasks', extra_paths)
    return class_util.find_subclasses_in_packages(package_paths, Task)


def load_image_builders(extra_paths=None):
    """
    Load all ImageBuilder extensions
    """
    package_paths = ['liminal.build.image'] + __generate_extra_paths('images', extra_paths)
    return class_util.find_subclasses_in_packages(package_paths, ImageBuilder)