# Copyright 2018 D-Wave Systems Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import logging
from concurrent.futures import ThreadPoolExecutor, ProcessPoolExecutor, Future, Executor
from hybrid.utils import cpu_count
__all__ = [
'immediate_executor', 'thread_executor'
]
logger = logging.getLogger(__name__)
[docs]class Present(Future):
"""Already resolved :class:`~concurrent.futures.Future` object.
Users should treat this class as just another
:class:`~concurrent.futures.Future`, the difference being an implementation
detail: :class:`Present` is "resolved" at construction time.
See the example of the :meth:`~hybrid.core.Runnable.run` method.
"""
def __init__(self, result=None, exception=None):
super(Present, self).__init__()
if result is not None:
self.set_result(result)
elif exception is not None:
self.set_exception(exception)
else:
raise ValueError("can't provide both 'result' and 'exception'")
class ImmediateExecutor(Executor):
def submit(self, fn, *args, **kwargs):
"""Blocking version of `Executor.submit()`. Returns a resolved
`Future`.
"""
try:
return Present(result=fn(*args, **kwargs))
except Exception as exc:
return Present(exception=exc)
thread_executor = ThreadPoolExecutor(max_workers=cpu_count() * 5)
process_executor = ProcessPoolExecutor(max_workers=cpu_count())
immediate_executor = ImmediateExecutor()