Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/urllib3/util/timeout.py: 41%
71 statements
« prev ^ index » next coverage.py v7.4.4, created at 2024-04-20 06:09 +0000
1from __future__ import annotations
3import time
4import typing
5from enum import Enum
6from socket import getdefaulttimeout
8from ..exceptions import TimeoutStateError
10if typing.TYPE_CHECKING:
11 from typing import Final
14class _TYPE_DEFAULT(Enum):
15 # This value should never be passed to socket.settimeout() so for safety we use a -1.
16 # socket.settimout() raises a ValueError for negative values.
17 token = -1
20_DEFAULT_TIMEOUT: Final[_TYPE_DEFAULT] = _TYPE_DEFAULT.token
22_TYPE_TIMEOUT = typing.Optional[typing.Union[float, _TYPE_DEFAULT]]
25class Timeout:
26 """Timeout configuration.
28 Timeouts can be defined as a default for a pool:
30 .. code-block:: python
32 import urllib3
34 timeout = urllib3.util.Timeout(connect=2.0, read=7.0)
36 http = urllib3.PoolManager(timeout=timeout)
38 resp = http.request("GET", "https://example.com/")
40 print(resp.status)
42 Or per-request (which overrides the default for the pool):
44 .. code-block:: python
46 response = http.request("GET", "https://example.com/", timeout=Timeout(10))
48 Timeouts can be disabled by setting all the parameters to ``None``:
50 .. code-block:: python
52 no_timeout = Timeout(connect=None, read=None)
53 response = http.request("GET", "https://example.com/", timeout=no_timeout)
56 :param total:
57 This combines the connect and read timeouts into one; the read timeout
58 will be set to the time leftover from the connect attempt. In the
59 event that both a connect timeout and a total are specified, or a read
60 timeout and a total are specified, the shorter timeout will be applied.
62 Defaults to None.
64 :type total: int, float, or None
66 :param connect:
67 The maximum amount of time (in seconds) to wait for a connection
68 attempt to a server to succeed. Omitting the parameter will default the
69 connect timeout to the system default, probably `the global default
70 timeout in socket.py
71 <http://hg.python.org/cpython/file/603b4d593758/Lib/socket.py#l535>`_.
72 None will set an infinite timeout for connection attempts.
74 :type connect: int, float, or None
76 :param read:
77 The maximum amount of time (in seconds) to wait between consecutive
78 read operations for a response from the server. Omitting the parameter
79 will default the read timeout to the system default, probably `the
80 global default timeout in socket.py
81 <http://hg.python.org/cpython/file/603b4d593758/Lib/socket.py#l535>`_.
82 None will set an infinite timeout.
84 :type read: int, float, or None
86 .. note::
88 Many factors can affect the total amount of time for urllib3 to return
89 an HTTP response.
91 For example, Python's DNS resolver does not obey the timeout specified
92 on the socket. Other factors that can affect total request time include
93 high CPU load, high swap, the program running at a low priority level,
94 or other behaviors.
96 In addition, the read and total timeouts only measure the time between
97 read operations on the socket connecting the client and the server,
98 not the total amount of time for the request to return a complete
99 response. For most requests, the timeout is raised because the server
100 has not sent the first byte in the specified time. This is not always
101 the case; if a server streams one byte every fifteen seconds, a timeout
102 of 20 seconds will not trigger, even though the request will take
103 several minutes to complete.
104 """
106 #: A sentinel object representing the default timeout value
107 DEFAULT_TIMEOUT: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT
109 def __init__(
110 self,
111 total: _TYPE_TIMEOUT = None,
112 connect: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
113 read: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
114 ) -> None:
115 self._connect = self._validate_timeout(connect, "connect")
116 self._read = self._validate_timeout(read, "read")
117 self.total = self._validate_timeout(total, "total")
118 self._start_connect: float | None = None
120 def __repr__(self) -> str:
121 return f"{type(self).__name__}(connect={self._connect!r}, read={self._read!r}, total={self.total!r})"
123 # __str__ provided for backwards compatibility
124 __str__ = __repr__
126 @staticmethod
127 def resolve_default_timeout(timeout: _TYPE_TIMEOUT) -> float | None:
128 return getdefaulttimeout() if timeout is _DEFAULT_TIMEOUT else timeout
130 @classmethod
131 def _validate_timeout(cls, value: _TYPE_TIMEOUT, name: str) -> _TYPE_TIMEOUT:
132 """Check that a timeout attribute is valid.
134 :param value: The timeout value to validate
135 :param name: The name of the timeout attribute to validate. This is
136 used to specify in error messages.
137 :return: The validated and casted version of the given value.
138 :raises ValueError: If it is a numeric value less than or equal to
139 zero, or the type is not an integer, float, or None.
140 """
141 if value is None or value is _DEFAULT_TIMEOUT:
142 return value
144 if isinstance(value, bool):
145 raise ValueError(
146 "Timeout cannot be a boolean value. It must "
147 "be an int, float or None."
148 )
149 try:
150 float(value)
151 except (TypeError, ValueError):
152 raise ValueError(
153 "Timeout value %s was %s, but it must be an "
154 "int, float or None." % (name, value)
155 ) from None
157 try:
158 if value <= 0:
159 raise ValueError(
160 "Attempted to set %s timeout to %s, but the "
161 "timeout cannot be set to a value less "
162 "than or equal to 0." % (name, value)
163 )
164 except TypeError:
165 raise ValueError(
166 "Timeout value %s was %s, but it must be an "
167 "int, float or None." % (name, value)
168 ) from None
170 return value
172 @classmethod
173 def from_float(cls, timeout: _TYPE_TIMEOUT) -> Timeout:
174 """Create a new Timeout from a legacy timeout value.
176 The timeout value used by httplib.py sets the same timeout on the
177 connect(), and recv() socket requests. This creates a :class:`Timeout`
178 object that sets the individual timeouts to the ``timeout`` value
179 passed to this function.
181 :param timeout: The legacy timeout value.
182 :type timeout: integer, float, :attr:`urllib3.util.Timeout.DEFAULT_TIMEOUT`, or None
183 :return: Timeout object
184 :rtype: :class:`Timeout`
185 """
186 return Timeout(read=timeout, connect=timeout)
188 def clone(self) -> Timeout:
189 """Create a copy of the timeout object
191 Timeout properties are stored per-pool but each request needs a fresh
192 Timeout object to ensure each one has its own start/stop configured.
194 :return: a copy of the timeout object
195 :rtype: :class:`Timeout`
196 """
197 # We can't use copy.deepcopy because that will also create a new object
198 # for _GLOBAL_DEFAULT_TIMEOUT, which socket.py uses as a sentinel to
199 # detect the user default.
200 return Timeout(connect=self._connect, read=self._read, total=self.total)
202 def start_connect(self) -> float:
203 """Start the timeout clock, used during a connect() attempt
205 :raises urllib3.exceptions.TimeoutStateError: if you attempt
206 to start a timer that has been started already.
207 """
208 if self._start_connect is not None:
209 raise TimeoutStateError("Timeout timer has already been started.")
210 self._start_connect = time.monotonic()
211 return self._start_connect
213 def get_connect_duration(self) -> float:
214 """Gets the time elapsed since the call to :meth:`start_connect`.
216 :return: Elapsed time in seconds.
217 :rtype: float
218 :raises urllib3.exceptions.TimeoutStateError: if you attempt
219 to get duration for a timer that hasn't been started.
220 """
221 if self._start_connect is None:
222 raise TimeoutStateError(
223 "Can't get connect duration for timer that has not started."
224 )
225 return time.monotonic() - self._start_connect
227 @property
228 def connect_timeout(self) -> _TYPE_TIMEOUT:
229 """Get the value to use when setting a connection timeout.
231 This will be a positive float or integer, the value None
232 (never timeout), or the default system timeout.
234 :return: Connect timeout.
235 :rtype: int, float, :attr:`Timeout.DEFAULT_TIMEOUT` or None
236 """
237 if self.total is None:
238 return self._connect
240 if self._connect is None or self._connect is _DEFAULT_TIMEOUT:
241 return self.total
243 return min(self._connect, self.total) # type: ignore[type-var]
245 @property
246 def read_timeout(self) -> float | None:
247 """Get the value for the read timeout.
249 This assumes some time has elapsed in the connection timeout and
250 computes the read timeout appropriately.
252 If self.total is set, the read timeout is dependent on the amount of
253 time taken by the connect timeout. If the connection time has not been
254 established, a :exc:`~urllib3.exceptions.TimeoutStateError` will be
255 raised.
257 :return: Value to use for the read timeout.
258 :rtype: int, float or None
259 :raises urllib3.exceptions.TimeoutStateError: If :meth:`start_connect`
260 has not yet been called on this object.
261 """
262 if (
263 self.total is not None
264 and self.total is not _DEFAULT_TIMEOUT
265 and self._read is not None
266 and self._read is not _DEFAULT_TIMEOUT
267 ):
268 # In case the connect timeout has not yet been established.
269 if self._start_connect is None:
270 return self._read
271 return max(0, min(self.total - self.get_connect_duration(), self._read))
272 elif self.total is not None and self.total is not _DEFAULT_TIMEOUT:
273 return max(0, self.total - self.get_connect_duration())
274 else:
275 return self.resolve_default_timeout(self._read)