# Copyright (C) 2012 Canonical Ltd. # Copyright (C) 2012 Hewlett-Packard Development Company, L.P. # Copyright (C) 2012 Yahoo! Inc. # # Author: Scott Moser <scott.moser@canonical.com> # Author: Juerg Haefliger <juerg.haefliger@hp.com> # Author: Joshua Harlow <harlowja@yahoo-inc.com> # # This file is part of cloud-init. See LICENSE file for license information. import importlib from types import ModuleType from typing import Optional, Sequence def import_module(module_name: str) -> ModuleType: return importlib.import_module(module_name) def _count_attrs( module_name: str, attrs: Optional[Sequence[str]] = None ) -> int: found_attrs = 0 if not attrs: return found_attrs mod = importlib.import_module(module_name) for attr in attrs: if hasattr(mod, attr): found_attrs += 1 return found_attrs def find_module( base_name: str, search_paths: Sequence[str], required_attrs: Optional[Sequence[str]] = None, ) -> tuple: """Finds specified modules""" if not required_attrs: required_attrs = [] # NOTE(harlowja): translate the search paths to include the base name. lookup_paths = [] for path in search_paths: real_path = [] if path: real_path.extend(path.split(".")) real_path.append(base_name) full_path = ".".join(real_path) lookup_paths.append(full_path) found_paths = [] for full_path in lookup_paths: if not importlib.util.find_spec(full_path): continue # Check that required_attrs are all present within the module. if _count_attrs(full_path, required_attrs) == len(required_attrs): found_paths.append(full_path) return (found_paths, lookup_paths) # vi: ts=4 expandtab