163 lines
5.0 KiB
Python
163 lines
5.0 KiB
Python
# Copyright 2022-present MongoDB, 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.
|
|
|
|
"""Internal helpers for CSOT."""
|
|
|
|
from __future__ import annotations
|
|
|
|
import functools
|
|
import inspect
|
|
import time
|
|
from collections import deque
|
|
from contextlib import AbstractContextManager
|
|
from contextvars import ContextVar, Token
|
|
from typing import TYPE_CHECKING, Any, Callable, Deque, MutableMapping, Optional, TypeVar, cast
|
|
|
|
if TYPE_CHECKING:
|
|
from pymongo.write_concern import WriteConcern
|
|
|
|
TIMEOUT: ContextVar[Optional[float]] = ContextVar("TIMEOUT", default=None)
|
|
RTT: ContextVar[float] = ContextVar("RTT", default=0.0)
|
|
DEADLINE: ContextVar[float] = ContextVar("DEADLINE", default=float("inf"))
|
|
|
|
|
|
def get_timeout() -> Optional[float]:
|
|
return TIMEOUT.get(None)
|
|
|
|
|
|
def get_rtt() -> float:
|
|
return RTT.get()
|
|
|
|
|
|
def get_deadline() -> float:
|
|
return DEADLINE.get()
|
|
|
|
|
|
def set_rtt(rtt: float) -> None:
|
|
RTT.set(rtt)
|
|
|
|
|
|
def remaining() -> Optional[float]:
|
|
if not get_timeout():
|
|
return None
|
|
return DEADLINE.get() - time.monotonic()
|
|
|
|
|
|
def clamp_remaining(max_timeout: float) -> float:
|
|
"""Return the remaining timeout clamped to a max value."""
|
|
timeout = remaining()
|
|
if timeout is None:
|
|
return max_timeout
|
|
return min(timeout, max_timeout)
|
|
|
|
|
|
class _TimeoutContext(AbstractContextManager):
|
|
"""Internal timeout context manager.
|
|
|
|
Use :func:`pymongo.timeout` instead::
|
|
|
|
with pymongo.timeout(0.5):
|
|
client.test.test.insert_one({})
|
|
"""
|
|
|
|
def __init__(self, timeout: Optional[float]):
|
|
self._timeout = timeout
|
|
self._tokens: Optional[tuple[Token[Optional[float]], Token[float], Token[float]]] = None
|
|
|
|
def __enter__(self) -> _TimeoutContext:
|
|
timeout_token = TIMEOUT.set(self._timeout)
|
|
prev_deadline = DEADLINE.get()
|
|
next_deadline = time.monotonic() + self._timeout if self._timeout else float("inf")
|
|
deadline_token = DEADLINE.set(min(prev_deadline, next_deadline))
|
|
rtt_token = RTT.set(0.0)
|
|
self._tokens = (timeout_token, deadline_token, rtt_token)
|
|
return self
|
|
|
|
def __exit__(self, exc_type: Any, exc_val: Any, exc_tb: Any) -> None:
|
|
if self._tokens:
|
|
timeout_token, deadline_token, rtt_token = self._tokens
|
|
TIMEOUT.reset(timeout_token)
|
|
DEADLINE.reset(deadline_token)
|
|
RTT.reset(rtt_token)
|
|
|
|
|
|
# See https://mypy.readthedocs.io/en/stable/generics.html?#decorator-factories
|
|
F = TypeVar("F", bound=Callable[..., Any])
|
|
|
|
|
|
def apply(func: F) -> F:
|
|
"""Apply the client's timeoutMS to this operation. Can wrap both asynchronous and synchronous methods"""
|
|
if inspect.iscoroutinefunction(func):
|
|
|
|
@functools.wraps(func)
|
|
async def csot_wrapper(self: Any, *args: Any, **kwargs: Any) -> Any:
|
|
if get_timeout() is None:
|
|
timeout = self._timeout
|
|
if timeout is not None:
|
|
with _TimeoutContext(timeout):
|
|
return await func(self, *args, **kwargs)
|
|
return await func(self, *args, **kwargs)
|
|
else:
|
|
|
|
@functools.wraps(func)
|
|
def csot_wrapper(self: Any, *args: Any, **kwargs: Any) -> Any:
|
|
if get_timeout() is None:
|
|
timeout = self._timeout
|
|
if timeout is not None:
|
|
with _TimeoutContext(timeout):
|
|
return func(self, *args, **kwargs)
|
|
return func(self, *args, **kwargs)
|
|
|
|
return cast(F, csot_wrapper)
|
|
|
|
|
|
def apply_write_concern(
|
|
cmd: MutableMapping[str, Any], write_concern: Optional[WriteConcern]
|
|
) -> None:
|
|
"""Apply the given write concern to a command."""
|
|
if not write_concern or write_concern.is_server_default:
|
|
return
|
|
wc = write_concern.document
|
|
if get_timeout() is not None:
|
|
wc.pop("wtimeout", None)
|
|
if wc:
|
|
cmd["writeConcern"] = wc
|
|
|
|
|
|
_MAX_RTT_SAMPLES: int = 10
|
|
_MIN_RTT_SAMPLES: int = 2
|
|
|
|
|
|
class MovingMinimum:
|
|
"""Tracks a minimum RTT within the last 10 RTT samples."""
|
|
|
|
samples: Deque[float]
|
|
|
|
def __init__(self) -> None:
|
|
self.samples = deque(maxlen=_MAX_RTT_SAMPLES)
|
|
|
|
def add_sample(self, sample: float) -> None:
|
|
if sample < 0:
|
|
raise ValueError(f"duration cannot be negative {sample}")
|
|
self.samples.append(sample)
|
|
|
|
def get(self) -> float:
|
|
"""Get the min, or 0.0 if there aren't enough samples yet."""
|
|
if len(self.samples) >= _MIN_RTT_SAMPLES:
|
|
return min(self.samples)
|
|
return 0.0
|
|
|
|
def reset(self) -> None:
|
|
self.samples.clear()
|