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-rw-r--r--requests-0.14.0/requests/packages/urllib3/_collections.py94
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diff --git a/requests-0.14.0/requests/packages/urllib3/_collections.py b/requests-0.14.0/requests/packages/urllib3/_collections.py
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+++ b/requests-0.14.0/requests/packages/urllib3/_collections.py
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+# urllib3/_collections.py
+# Copyright 2008-2012 Andrey Petrov and contributors (see CONTRIBUTORS.txt)
+#
+# This module is part of urllib3 and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from collections import MutableMapping
+from threading import Lock
+
+try: # Python 2.7+
+ from collections import OrderedDict
+except ImportError:
+ from .packages.ordered_dict import OrderedDict
+
+
+__all__ = ['RecentlyUsedContainer']
+
+
+_Null = object()
+
+
+class RecentlyUsedContainer(MutableMapping):
+ """
+ Provides a thread-safe dict-like container which maintains up to
+ ``maxsize`` keys while throwing away the least-recently-used keys beyond
+ ``maxsize``.
+
+ :param maxsize:
+ Maximum number of recent elements to retain.
+
+ :param dispose_func:
+ Every time an item is evicted from the container,
+ ``dispose_func(value)`` is called. Callback which will get called
+ """
+
+ ContainerCls = OrderedDict
+
+ def __init__(self, maxsize=10, dispose_func=None):
+ self._maxsize = maxsize
+ self.dispose_func = dispose_func
+
+ self._container = self.ContainerCls()
+ self._lock = Lock()
+
+ def __getitem__(self, key):
+ # Re-insert the item, moving it to the end of the eviction line.
+ with self._lock:
+ item = self._container.pop(key)
+ self._container[key] = item
+ return item
+
+ def __setitem__(self, key, value):
+ evicted_value = _Null
+ with self._lock:
+ # Possibly evict the existing value of 'key'
+ evicted_value = self._container.get(key, _Null)
+ self._container[key] = value
+
+ # If we didn't evict an existing value, we might have to evict the
+ # least recently used item from the beginning of the container.
+ if len(self._container) > self._maxsize:
+ _key, evicted_value = self._container.popitem(last=False)
+
+ if self.dispose_func and evicted_value is not _Null:
+ self.dispose_func(evicted_value)
+
+ def __delitem__(self, key):
+ with self._lock:
+ value = self._container.pop(key)
+
+ if self.dispose_func:
+ self.dispose_func(value)
+
+ def __len__(self):
+ with self._lock:
+ return len(self._container)
+
+ def __iter__(self):
+ raise NotImplementedError('Iteration over this class is unlikely to be threadsafe.')
+
+ def clear(self):
+ with self._lock:
+ # Copy pointers to all values, then wipe the mapping
+ # under Python 2, this copies the list of values twice :-|
+ values = list(self._container.values())
+ self._container.clear()
+
+ if self.dispose_func:
+ for value in values:
+ self.dispose_func(value)
+
+ def keys(self):
+ with self._lock:
+ return self._container.keys()