diff options
Diffstat (limited to 'urllib3/util/timeout.py')
| -rw-r--r-- | urllib3/util/timeout.py | 67 |
1 files changed, 37 insertions, 30 deletions
diff --git a/urllib3/util/timeout.py b/urllib3/util/timeout.py index aaadc12..ea7027f 100644 --- a/urllib3/util/timeout.py +++ b/urllib3/util/timeout.py @@ -1,32 +1,49 @@ +# The default socket timeout, used by httplib to indicate that no timeout was +# specified by the user from socket import _GLOBAL_DEFAULT_TIMEOUT import time from ..exceptions import TimeoutStateError +# A sentinel value to indicate that no timeout was specified by the user in +# urllib3 +_Default = object() def current_time(): """ - Retrieve the current time, this function is mocked out in unit testing. + Retrieve the current time. This function is mocked out in unit testing. """ return time.time() -_Default = object() -# The default timeout to use for socket connections. This is the attribute used -# by httplib to define the default timeout +class Timeout(object): + """ Timeout configuration. + Timeouts can be defined as a default for a pool:: -class Timeout(object): - """ - Utility object for storing timeout values. + timeout = Timeout(connect=2.0, read=7.0) + http = PoolManager(timeout=timeout) + response = http.request('GET', 'http://example.com/') + + Or per-request (which overrides the default for the pool):: + + response = http.request('GET', 'http://example.com/', timeout=Timeout(10)) - Example usage: + Timeouts can be disabled by setting all the parameters to ``None``:: + + no_timeout = Timeout(connect=None, read=None) + response = http.request('GET', 'http://example.com/, timeout=no_timeout) + + + :param total: + This combines the connect and read timeouts into one; the read timeout + will be set to the time leftover from the connect attempt. In the + event that both a connect timeout and a total are specified, or a read + timeout and a total are specified, the shorter timeout will be applied. - .. code-block:: python + Defaults to None. - timeout = urllib3.util.Timeout(connect=2.0, read=7.0) - pool = HTTPConnectionPool('www.google.com', 80, timeout=timeout) - pool.request(...) # Etc, etc + :type total: integer, float, or None :param connect: The maximum amount of time to wait for a connection attempt to a server @@ -47,25 +64,15 @@ class Timeout(object): :type read: integer, float, or None - :param total: - This combines the connect and read timeouts into one; the read timeout - will be set to the time leftover from the connect attempt. In the - event that both a connect timeout and a total are specified, or a read - timeout and a total are specified, the shorter timeout will be applied. - - Defaults to None. - - :type total: integer, float, or None - .. note:: Many factors can affect the total amount of time for urllib3 to return - an HTTP response. Specifically, Python's DNS resolver does not obey the - timeout specified on the socket. Other factors that can affect total - request time include high CPU load, high swap, the program running at a - low priority level, or other behaviors. The observed running time for - urllib3 to return a response may be greater than the value passed to - `total`. + an HTTP response. + + For example, Python's DNS resolver does not obey the timeout specified + on the socket. Other factors that can affect total request time include + high CPU load, high swap, the program running at a low priority level, + or other behaviors. In addition, the read and total timeouts only measure the time between read operations on the socket connecting the client and the server, @@ -73,8 +80,8 @@ class Timeout(object): response. For most requests, the timeout is raised because the server has not sent the first byte in the specified time. This is not always the case; if a server streams one byte every fifteen seconds, a timeout - of 20 seconds will not ever trigger, even though the request will - take several minutes to complete. + of 20 seconds will not trigger, even though the request will take + several minutes to complete. If your goal is to cut off any request after a set amount of wall clock time, consider having a second "watcher" thread to cut off a slow |