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
|
import logging
import re
from typing import Callable, Iterable, List, Optional, Tuple, Type, Union
import pytest
RecordFilter = Callable[[logging.LogRecord], bool]
ExceptionType = Union[Type[BaseException], Tuple[Type[BaseException], ...]]
def _get_log_level_no(level: Union[int, str]) -> int:
return logging._checkLevel(level) # type: ignore
class LogPile:
__slots__ = ("_records",)
_records: List[logging.LogRecord]
def __init__(self, records: Iterable[logging.LogRecord] = ()):
self._records = list(records)
def __len__(self):
return len(self._records)
def __iter__(self):
return iter(self._records)
# `assert pile.is_empty()` is more readable than `assert not pile`
def is_empty(self) -> bool:
"""Return True if the pile is empty, False otherwise."""
return not self._records
def _add(self, record):
self._records.append(record)
def messages(self) -> List[str]:
return [record.getMessage() for record in self._records]
def _partition(
self,
func: Optional[RecordFilter] = None,
*,
name: Optional[str] = None,
level: Union[None, int, str] = None,
message: Optional[str] = None,
exc_info: Union[None, bool, ExceptionType] = None,
stack_info: Optional[bool] = None,
) -> Tuple[List[logging.LogRecord], List[logging.LogRecord]]:
filters = []
if func is not None:
filters.append(func)
if name is not None:
def _filter(record):
# The same behavior as for `logging.Filter(name=...)`
return (
record.name == name
or record.name.startswith(f"{name}.")
)
filters.append(_filter)
if level is not None:
levelno = _get_log_level_no(level)
if levelno:
def _filter(record):
return record.levelno >= levelno
filters.append(_filter)
if message is not None:
def _filter(record):
return re.search(message, record.getMessage())
filters.append(_filter)
if exc_info is not None:
if isinstance(exc_info, (type, tuple)):
exc_type = exc_info
def _filter(record):
return (
record.exc_info is not None
and isinstance(record.exc_info[1], exc_type)
)
else:
has_exc_info = bool(exc_info)
def _filter(record):
return (record.exc_info is not None) == has_exc_info
filters.append(_filter)
if stack_info is not None:
has_stack_info = bool(stack_info)
def _filter(record):
return (record.stack_info is not None) == has_stack_info
filters.append(_filter)
matching = []
rest = []
for record in self._records:
if all(matches(record) for matches in filters):
matching.append(record)
else:
rest.append(record)
return matching, rest
def filter(
self,
func: Optional[RecordFilter] = None,
*,
name: Optional[str] = None,
level: Union[None, int, str] = None,
message: Optional[str] = None,
exc_info: Union[None, bool, ExceptionType] = None,
stack_info: Optional[bool] = None,
) -> "LogPile":
"""Return list of matching log records."""
matching, _ = self._partition(
func, name=name, level=level, message=message, exc_info=exc_info,
stack_info=stack_info
)
return LogPile(matching)
def drain(
self,
func: Optional[RecordFilter] = None,
*,
name: Optional[str] = None,
level: Union[None, int, str] = None,
message: Optional[str] = None,
exc_info: Union[None, bool, ExceptionType] = None,
stack_info: Optional[bool] = None,
) -> "LogPile":
"""Return list of matching log records and remove them from the pile.
"""
matching, rest = self._partition(
func, name=name, level=level, message=message, exc_info=exc_info,
stack_info=stack_info
)
# Atomically update without locks
count = len(matching) + len(rest)
self._records[:count] = rest
# Commented buggy version to ensure test catches the race:
# self._records = rest
return LogPile(matching)
class LogHandler(logging.Handler):
__slots__ = ("_pile",)
def __init__(self, pile):
super().__init__()
self._pile = pile
def handle(self, record):
self._pile._records.append(record)
class LogDog:
__slots__ = ("_logger", "_handler", "_orig_level", "_level")
def __init__(
self,
name: Optional[str] = None,
level: Union[None, int, str] = None,
):
self._logger = logging.getLogger(name)
self._level = level
def __enter__(self):
pile = LogPile()
self._handler = LogHandler(pile)
if self._level is not None:
self._handler.setLevel(self._level)
self._logger.addHandler(self._handler)
if self._level is not None:
self._orig_level = self._logger.level
# Argument `level` can be `None`, `int` or `str`, while
# `handler.level` is always `int` (converted by `setLevel()`
# method)
self._logger.setLevel(min(self._orig_level, self._handler.level))
return pile
def __exit__(self, type, value, traceback):
if self._level is not None:
self._logger.setLevel(self._orig_level)
self._logger.removeHandler(self._handler)
@pytest.fixture
def logdog():
"""Scoped log capturing and testing tool."""
return LogDog
|
