JezK
Edit File: retry.py
# Copyright 2016–2021 Julien Danjou # Copyright 2016 Joshua Harlow # Copyright 2013-2014 Ray Holder # # 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 abc import re import typing if typing.TYPE_CHECKING: from pip._vendor.tenacity import RetryCallState class retry_base(abc.ABC): """Abstract base class for retry strategies.""" @abc.abstractmethod def __call__(self, retry_state: "RetryCallState") -> bool: pass def __and__(self, other: "retry_base") -> "retry_all": return retry_all(self, other) def __or__(self, other: "retry_base") -> "retry_any": return retry_any(self, other) class _retry_never(retry_base): """Retry strategy that never rejects any result.""" def __call__(self, retry_state: "RetryCallState") -> bool: return False retry_never = _retry_never() class _retry_always(retry_base): """Retry strategy that always rejects any result.""" def __call__(self, retry_state: "RetryCallState") -> bool: return True retry_always = _retry_always() class retry_if_exception(retry_base): """Retry strategy that retries if an exception verifies a predicate.""" def __init__(self, predicate: typing.Callable[[BaseException], bool]) -> None: self.predicate = predicate def __call__(self, retry_state: "RetryCallState") -> bool: if retry_state.outcome.failed: return self.predicate(retry_state.outcome.exception()) else: return False class retry_if_exception_type(retry_if_exception): """Retries if an exception has been raised of one or more types.""" def __init__( self, exception_types: typing.Union[ typing.Type[BaseException], typing.Tuple[typing.Type[BaseException], ...], ] = Exception, ) -> None: self.exception_types = exception_types super().__init__(lambda e: isinstance(e, exception_types)) class retry_if_not_exception_type(retry_if_exception): """Retries except an exception has been raised of one or more types.""" def __init__( self, exception_types: typing.Union[ typing.Type[BaseException], typing.Tuple[typing.Type[BaseException], ...], ] = Exception, ) -> None: self.exception_types = exception_types super().__init__(lambda e: not isinstance(e, exception_types)) class retry_unless_exception_type(retry_if_exception): """Retries until an exception is raised of one or more types.""" def __init__( self, exception_types: typing.Union[ typing.Type[BaseException], typing.Tuple[typing.Type[BaseException], ...], ] = Exception, ) -> None: self.exception_types = exception_types super().__init__(lambda e: not isinstance(e, exception_types)) def __call__(self, retry_state: "RetryCallState") -> bool: # always retry if no exception was raised if not retry_state.outcome.failed: return True return self.predicate(retry_state.outcome.exception()) class retry_if_exception_cause_type(retry_base): """Retries if any of the causes of the raised exception is of one or more types. The check on the type of the cause of the exception is done recursively (until finding an exception in the chain that has no `__cause__`) """ def __init__( self, exception_types: typing.Union[ typing.Type[BaseException], typing.Tuple[typing.Type[BaseException], ...], ] = Exception, ) -> None: self.exception_cause_types = exception_types def __call__(self, retry_state: "RetryCallState") -> bool: if retry_state.outcome.failed: exc = retry_state.outcome.exception() while exc is not None: if isinstance(exc.__cause__, self.exception_cause_types): return True exc = exc.__cause__ return False class retry_if_result(retry_base): """Retries if the result verifies a predicate.""" def __init__(self, predicate: typing.Callable[[typing.Any], bool]) -> None: self.predicate = predicate def __call__(self, retry_state: "RetryCallState") -> bool: if not retry_state.outcome.failed: return self.predicate(retry_state.outcome.result()) else: return False class retry_if_not_result(retry_base): """Retries if the result refutes a predicate.""" def __init__(self, predicate: typing.Callable[[typing.Any], bool]) -> None: self.predicate = predicate def __call__(self, retry_state: "RetryCallState") -> bool: if not retry_state.outcome.failed: return not self.predicate(retry_state.outcome.result()) else: return False class retry_if_exception_message(retry_if_exception): """Retries if an exception message equals or matches.""" def __init__( self, message: typing.Optional[str] = None, match: typing.Optional[str] = None, ) -> None: if message and match: raise TypeError(f"{self.__class__.__name__}() takes either 'message' or 'match', not both") # set predicate if message: def message_fnc(exception: BaseException) -> bool: return message == str(exception) predicate = message_fnc elif match: prog = re.compile(match) def match_fnc(exception: BaseException) -> bool: return bool(prog.match(str(exception))) predicate = match_fnc else: raise TypeError(f"{self.__class__.__name__}() missing 1 required argument 'message' or 'match'") super().__init__(predicate) class retry_if_not_exception_message(retry_if_exception_message): """Retries until an exception message equals or matches.""" def __init__( self, message: typing.Optional[str] = None, match: typing.Optional[str] = None, ) -> None: super().__init__(message, match) # invert predicate if_predicate = self.predicate self.predicate = lambda *args_, **kwargs_: not if_predicate(*args_, **kwargs_) def __call__(self, retry_state: "RetryCallState") -> bool: if not retry_state.outcome.failed: return True return self.predicate(retry_state.outcome.exception()) class retry_any(retry_base): """Retries if any of the retries condition is valid.""" def __init__(self, *retries: retry_base) -> None: self.retries = retries def __call__(self, retry_state: "RetryCallState") -> bool: return any(r(retry_state) for r in self.retries) class retry_all(retry_base): """Retries if all the retries condition are valid.""" def __init__(self, *retries: retry_base) -> None: self.retries = retries def __call__(self, retry_state: "RetryCallState") -> bool: return all(r(retry_state) for r in self.retries)