1 files changed, 74 insertions, 0 deletions
diff --git a/urllib3/util/sessioncontext.py b/urllib3/util/sessioncontext.py
new file mode 100644
index 00000000..3b323dca
--- /dev/null
+++ b/urllib3/util/sessioncontext.py
@@ -0,0 +1,74 @@
+import time
+
+from ..packages.six.moves.http_cookiejar import (
+    DefaultCookiePolicy as PythonCookiePolicy,
+    CookieJar as PythonCookieJar
+)
+
+
+class DefaultCookiePolicy(PythonCookiePolicy):
+    """
+    The default urllib3 cookie policy - similar to the Python default,
+    but :param:`strict_ns_domain` is set to `DomainStrict` for security.
+    """
+    def __init__(self, *args, **kwargs):
+        policy = PythonCookiePolicy.DomainStrict
+        kwargs.setdefault('strict_ns_domain', policy)
+        # Old-style class on Python 2
+        PythonCookiePolicy.__init__(self, *args, **kwargs)
+
+
+class CookieJar(PythonCookieJar):
+
+    def __init__(self, policy=None):
+        if policy is None:
+            policy = DefaultCookiePolicy()
+        # Old-style class on Python 2
+        PythonCookieJar.__init__(self, policy=policy)
+
+    def add_cookie_header(self, request):
+        """
+        Add correct Cookie: header to Request object.
+        This is copied from and slightly modified from the stdlib version.
+        """
+        with self._cookies_lock:
+            self._policy._now = self._now = int(time.time())
+            cookies = self._cookies_for_request(request)
+            attrs = self._cookie_attrs(cookies)
+            # This is a modification; stdlib sets the entire cookie header
+            # and only if it's not there already. We're less picky.
+            if attrs:
+                request.add_cookies(*attrs)
+
+        self.clear_expired_cookies()
+
+
+class SessionContext(object):
+    """
+    Extensible class encapsulated by :class:`.SessionManager`; currently
+    used to manage cookies.
+
+    :param cookie_jar:
+        Used to pass a prebuilt :class:`CookieJar` into the
+        context to be used instead of an empty jar.
+    """
+
+    def __init__(self, cookie_jar=None):
+        # We unfortunately have to do it this way; empty cookie jars
+        # evaluate as falsey.
+        if cookie_jar is not None:
+            self.cookie_jar = cookie_jar
+        else:
+            self.cookie_jar = CookieJar()
+
+    def apply_to(self, request):
+        """
+        Applies changes from the context to the supplied :class:`.request.Request`.
+        """
+        self.cookie_jar.add_cookie_header(request)
+
+    def extract_from(self, response, request):
+        """
+        Extracts context modifications (new cookies, etc) from the response and stores them.
+        """
+        self.cookie_jar.extract_cookies(response, request)