Imported Upstream version 1.8.3

4 files changed, 33 insertions, 28 deletions

diff --git a/urllib3/util/connection.py b/urllib3/util/connection.py
index 8deeab5..c67ef04 100644
--- a/urllib3/util/connection.py
+++ b/urllib3/util/connection.py
@@ -8,6 +8,7 @@ except ImportError:  # `poll` doesn't exist on OSX and other platforms
     except ImportError:  # `select` doesn't exist on AppEngine.
         select = False
 
+
 def is_connection_dropped(conn):  # Platform-specific
     """
     Returns True if the connection is dropped and should be closed.
@@ -22,7 +23,7 @@ def is_connection_dropped(conn):  # Platform-specific
     if sock is False:  # Platform-specific: AppEngine
         return False
     if sock is None:  # Connection already closed (such as by httplib).
-        return False
+        return True
 
     if not poll:
         if not select:  # Platform-specific: AppEngine
@@ -40,6 +41,3 @@ def is_connection_dropped(conn):  # Platform-specific
         if fno == sock.fileno():
             # Either data is buffered (bad), or the connection is dropped.
             return True
-
-
-
diff --git a/urllib3/util/request.py b/urllib3/util/request.py
index d48d651..bfd7a98 100644
--- a/urllib3/util/request.py
+++ b/urllib3/util/request.py
@@ -7,7 +7,7 @@ ACCEPT_ENCODING = 'gzip,deflate'
 
 
 def make_headers(keep_alive=None, accept_encoding=None, user_agent=None,
-                 basic_auth=None, proxy_basic_auth=None):
+                 basic_auth=None, proxy_basic_auth=None, disable_cache=None):
     """
     Shortcuts for generating request headers.
 
@@ -29,8 +29,11 @@ def make_headers(keep_alive=None, accept_encoding=None, user_agent=None,
         auth header.
 
     :param proxy_basic_auth:
-        Colon-separated username:password string for 'proxy-authorization: basic ...'
-        auth header.
+        Colon-separated username:password string for
+        'proxy-authorization: basic ...' auth header.
+
+    :param disable_cache:
+        If ``True``, adds 'cache-control: no-cache' header.
 
     Example: ::
 
@@ -63,6 +66,7 @@ def make_headers(keep_alive=None, accept_encoding=None, user_agent=None,
         headers['proxy-authorization'] = 'Basic ' + \
             b64encode(six.b(proxy_basic_auth)).decode('utf-8')
 
-    return headers
-
+    if disable_cache:
+        headers['cache-control'] = 'no-cache'
 
+    return headers
diff --git a/urllib3/util/timeout.py b/urllib3/util/timeout.py
index 4f947cb..aaadc12 100644
--- a/urllib3/util/timeout.py
+++ b/urllib3/util/timeout.py
@@ -94,17 +94,16 @@ class Timeout(object):
         return '%s(connect=%r, read=%r, total=%r)' % (
             type(self).__name__, self._connect, self._read, self.total)
 
-
     @classmethod
     def _validate_timeout(cls, value, name):
-        """ Check that a timeout attribute is valid
+        """ Check that a timeout attribute is valid.
 
         :param value: The timeout value to validate
-        :param name: The name of the timeout attribute to validate. This is used
-            for clear error messages
-        :return: the value
-        :raises ValueError: if the type is not an integer or a float, or if it
-            is a numeric value less than zero
+        :param name: The name of the timeout attribute to validate. This is
+            used to specify in error messages.
+        :return: The validated and casted version of the given value.
+        :raises ValueError: If the type is not an integer or a float, or if it
+            is a numeric value less than zero.
         """
         if value is _Default:
             return cls.DEFAULT_TIMEOUT
@@ -123,7 +122,7 @@ class Timeout(object):
                 raise ValueError("Attempted to set %s timeout to %s, but the "
                                  "timeout cannot be set to a value less "
                                  "than 0." % (name, value))
-        except TypeError: # Python 3
+        except TypeError:  # Python 3
             raise ValueError("Timeout value %s was %s, but it must be an "
                              "int or float." % (name, value))
 
@@ -135,12 +134,12 @@ class Timeout(object):
 
         The timeout value used by httplib.py sets the same timeout on the
         connect(), and recv() socket requests. This creates a :class:`Timeout`
-        object that sets the individual timeouts to the ``timeout`` value passed
-        to this function.
+        object that sets the individual timeouts to the ``timeout`` value
+        passed to this function.
 
-        :param timeout: The legacy timeout value
+        :param timeout: The legacy timeout value.
         :type timeout: integer, float, sentinel default object, or None
-        :return: a Timeout object
+        :return: Timeout object
         :rtype: :class:`Timeout`
         """
         return Timeout(read=timeout, connect=timeout)
@@ -174,7 +173,7 @@ class Timeout(object):
     def get_connect_duration(self):
         """ Gets the time elapsed since the call to :meth:`start_connect`.
 
-        :return: the elapsed time
+        :return: Elapsed time.
         :rtype: float
         :raises urllib3.exceptions.TimeoutStateError: if you attempt
             to get duration for a timer that hasn't been started.
@@ -191,7 +190,7 @@ class Timeout(object):
         This will be a positive float or integer, the value None
         (never timeout), or the default system timeout.
 
-        :return: the connect timeout
+        :return: Connect timeout.
         :rtype: int, float, :attr:`Timeout.DEFAULT_TIMEOUT` or None
         """
         if self.total is None:
@@ -214,7 +213,7 @@ class Timeout(object):
         established, a :exc:`~urllib3.exceptions.TimeoutStateError` will be
         raised.
 
-        :return: the value to use for the read timeout
+        :return: Value to use for the read timeout.
         :rtype: int, float, :attr:`Timeout.DEFAULT_TIMEOUT` or None
         :raises urllib3.exceptions.TimeoutStateError: If :meth:`start_connect`
             has not yet been called on this object.
@@ -223,7 +222,7 @@ class Timeout(object):
             self.total is not self.DEFAULT_TIMEOUT and
             self._read is not None and
             self._read is not self.DEFAULT_TIMEOUT):
-            # in case the connect timeout has not yet been established.
+            # In case the connect timeout has not yet been established.
             if self._start_connect is None:
                 return self._read
             return max(0, min(self.total - self.get_connect_duration(),
diff --git a/urllib3/util/url.py b/urllib3/util/url.py
index 362d216..122108b 100644
--- a/urllib3/util/url.py
+++ b/urllib3/util/url.py
@@ -2,16 +2,20 @@ from collections import namedtuple
 
 from ..exceptions import LocationParseError
 
+url_attrs = ['scheme', 'auth', 'host', 'port', 'path', 'query', 'fragment']
 
-class Url(namedtuple('Url', ['scheme', 'auth', 'host', 'port', 'path', 'query', 'fragment'])):
+
+class Url(namedtuple('Url', url_attrs)):
     """
     Datastructure for representing an HTTP URL. Used as a return value for
     :func:`parse_url`.
     """
     slots = ()
 
-    def __new__(cls, scheme=None, auth=None, host=None, port=None, path=None, query=None, fragment=None):
-        return super(Url, cls).__new__(cls, scheme, auth, host, port, path, query, fragment)
+    def __new__(cls, scheme=None, auth=None, host=None, port=None, path=None,
+                query=None, fragment=None):
+        return super(Url, cls).__new__(cls, scheme, auth, host, port, path,
+                                       query, fragment)
 
     @property
     def hostname(self):