pyzmq/zmq/backend/__init__.py

35 lines
940 B
Python

"""Import basic exposure of libzmq C API as a backend"""
# Copyright (C) PyZMQ Developers
# Distributed under the terms of the Modified BSD License.
import os
import platform
from .select import public_api, select_backend
if 'PYZMQ_BACKEND' in os.environ:
backend = os.environ['PYZMQ_BACKEND']
if backend in ('cython', 'cffi'):
backend = f'zmq.backend.{backend}'
_ns = select_backend(backend)
else:
# default to cython, fallback to cffi
# (reverse on PyPy)
if platform.python_implementation() == 'PyPy':
first, second = ('zmq.backend.cffi', 'zmq.backend.cython')
else:
first, second = ('zmq.backend.cython', 'zmq.backend.cffi')
try:
_ns = select_backend(first)
except Exception as original_error:
try:
_ns = select_backend(second)
except ImportError:
raise original_error from None
globals().update(_ns)
__all__ = public_api