1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
|
# 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 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)
RetryBaseT = typing.Union[retry_base, typing.Callable[["RetryCallState"], bool]]
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 is None:
raise RuntimeError("__call__() called before outcome was set")
if retry_state.outcome.failed:
exception = retry_state.outcome.exception()
if exception is None:
raise RuntimeError("outcome failed but the exception is None")
return self.predicate(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:
if retry_state.outcome is None:
raise RuntimeError("__call__() called before outcome was set")
# always retry if no exception was raised
if not retry_state.outcome.failed:
return True
exception = retry_state.outcome.exception()
if exception is None:
raise RuntimeError("outcome failed but the exception is None")
return self.predicate(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 is None:
raise RuntimeError("__call__ called before outcome was set")
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 retry_state.outcome is None:
raise RuntimeError("__call__() called before outcome was set")
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 retry_state.outcome is None:
raise RuntimeError("__call__() called before outcome was set")
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 retry_state.outcome is None:
raise RuntimeError("__call__() called before outcome was set")
if not retry_state.outcome.failed:
return True
exception = retry_state.outcome.exception()
if exception is None:
raise RuntimeError("outcome failed but the exception is None")
return self.predicate(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)
|
