pvc/client-cli/pvc/lib/lazy_imports.py
2025-03-13 01:04:57 -04:00

38 lines
1.4 KiB
Python

#!/usr/bin/env python3
# lazy_imports.py - Lazy module importer library
# Part of the Parallel Virtual Cluster (PVC) system
#
# Copyright (C) 2018-2024 Joshua M. Boniface <joshua@boniface.me>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 3.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
#
###############################################################################
class LazyModule:
"""
A proxy for a module that is loaded only when actually used
"""
def __init__(self, name):
self.name = name
self._module = None
def __getattr__(self, attr):
if self._module is None:
import importlib
self._module = importlib.import_module(self.name)
return getattr(self._module, attr)
# Create lazy module proxies
yaml = LazyModule('yaml')
click_advanced = LazyModule('click') # For advanced click features not used at startup