Drop support for Python 2.7 up to 3.6.

setup.py

@@ -12,7 +12,7 @@
 #
 ##############################################################################
 # This package is developed by the Zope Toolkit project, documented here:
-# http://docs.zope.org/zopetoolkit
+# https://zopetoolkit.readthedocs.io/
 # When developing and releasing this package, please follow the documented
 # Zope Toolkit policies as described by this documentation.
 ##############################################################################
@@ -39,7 +39,7 @@ def read(*rnames):
 setup(name='zope.session',
       version='5.0.dev0',
       author='Zope Foundation and Contributors',
-      author_email='zope-dev@zope.org',
+      author_email='zope-dev@zope.dev',
       description='Client identification and sessions for Zope',
       long_description=(
           read('README.rst')
@@ -54,11 +54,7 @@ def read(*rnames):
           'Intended Audience :: Developers',
           'License :: OSI Approved :: Zope Public License',
           'Programming Language :: Python',
-          'Programming Language :: Python :: 2',
-          'Programming Language :: Python :: 2.7',
           'Programming Language :: Python :: 3',
-          'Programming Language :: Python :: 3.5',
-          'Programming Language :: Python :: 3.6',
           'Programming Language :: Python :: 3.7',
           'Programming Language :: Python :: 3.8',
           'Programming Language :: Python :: 3.9',
@@ -75,6 +71,7 @@ def read(*rnames):
       packages=find_packages('src'),
       package_dir={'': 'src'},
       namespace_packages=['zope', ],
+      python_requires='>=3.7',
       install_requires=[
           'setuptools',
           'ZODB >= 4.2.0.b1',

src/zope/session/http.py

@@ -20,14 +20,7 @@
 import time
 from email.utils import formatdate
 from hashlib import sha1
-
-
-try:
-    # Python 3.3+: OS-independent CPU counter
-    from time import process_time
-except ImportError:  # pragma: no cover
-    # Python 2.7
-    from time import clock as process_time
+from time import process_time
 
 import zope.location
 from persistent import Persistent
@@ -188,7 +181,7 @@ def __init__(self, namespace=None, secret=None):
         if namespace is None:
             namespace = "zope3_cs_%x" % (int(time.time()) - 1000000000)
         if secret is None:
-            secret = u'%.20f' % random.random()
+            secret = '%.20f' % random.random()
         self.namespace = namespace
         self.secret = secret
 
@@ -221,7 +214,7 @@ def getClientId(self, request):
         an `.IClientId`. This is because this method is used to implement
         the `.IClientId` Adapter.
 
-          >>> type(id) == type(u'')
+          >>> type(id) == str
           True
 
         We don't set the client id unless we need to, so, for example,
@@ -249,7 +242,7 @@ def getClientId(self, request):
           >>> bim.getClientId(request)
           Traceback (most recent call last):
           ...
-          MissingClientIdException
+          zope.session.http.MissingClientIdException
 
           >>> print(request.response.getCookie(bim.namespace))
           None
@@ -274,7 +267,7 @@ def getClientId(self, request):
           >>> bim.getClientId(request)
           Traceback (most recent call last):
           ...
-          MissingClientIdException
+          zope.session.http.MissingClientIdException
 
           >>> print(request.response.getCookie(bim.namespace))
           None
@@ -305,7 +298,7 @@ def generateUniqueId(self):
           True
 
         """
-        data = "%.20f%.20f%.20f" % (
+        data = "{:.20f}{:.20f}{:.20f}".format(
             random.random(), time.time(), process_time())
         digest = sha1(data.encode()).digest()
         s = digestEncode(digest)
@@ -492,7 +485,7 @@ def setRequestId(self, request, id):
 
         If the domain is specified, it will be set as a cookie attribute.
 
-          >>> bim.domain = u'.example.org'
+          >>> bim.domain = '.example.org'
           >>> bim.setRequestId(request, '1234')
           >>> cookie = request.response.getCookie(bim.namespace)
           >>> print(cookie['domain'])

src/zope/session/interfaces.py

@@ -69,7 +69,7 @@ class ISessionDataContainer(IReadMapping, IWriteMapping):
     :meth:`values` etc.
     """
     timeout = schema.Int(
-        title=_(u"Timeout"),
+        title=_("Timeout"),
         description=_(
             "Number of seconds before data becomes stale and may "
             "be removed. A value of '0' means no expiration."),

src/zope/session/session.py

@@ -16,8 +16,10 @@
 import base64
 import random
 import time
+from collections import UserDict
 from heapq import heapify
 from heapq import heappop
+from threading import get_ident
 
 import persistent
 import ZODB
@@ -38,38 +40,17 @@
 from zope.session.interfaces import ISessionPkgData
 
 
-try:
-    from UserDict import IterableUserDict as UserDict
-except ImportError:
-    # Py3: New UserDict location.
-    from collections import UserDict
-
-try:
-    from thread import get_ident
-except ImportError:
-    # Py3: New get_ident location
-    from threading import get_ident
-
-_PY3 = bytes is not str
-encodebytes = base64.encodebytes if _PY3 else base64.encodestring
-text_type = str if _PY3 else unicode  # noqa: F821 undefined name 'unicode' PY2
-
-try:
-    import string
-    transtable = string.maketrans(b'+/', b'-.')
-except AttributeError:
-    # Python 3
-    transtable = bytes.maketrans(b'+/', b'-.')
+transtable = bytes.maketrans(b'+/', b'-.')
 
 
 def digestEncode(s):
     """Encode SHA digest for cookie."""
-    return encodebytes(s)[:-2].translate(transtable)
+    return base64.encodebytes(s)[:-2].translate(transtable)
 
 
 @zope.interface.implementer(IClientId)
 @zope.component.adapter(IRequest)
-class ClientId(text_type):
+class ClientId(str):
     """
     Default implementation of `zope.session.interfaces.IClientId`.
 
@@ -102,7 +83,7 @@ class ClientId(text_type):
     def __new__(cls, request):
         id_manager = zope.component.getUtility(IClientIdManager)
         cid = id_manager.getClientId(request)
-        return text_type.__new__(cls, cid)
+        return str.__new__(cls, cid)
 
 
 @zope.interface.implementer(ISessionDataContainer)
@@ -372,7 +353,7 @@ def __init__(self):
         self.resolution = 5 * 60
         self.timeout = 1 * 60 * 60
         # Something unique
-        self.key = '%s.%s.%s' % (time.time(), random.random(), id(self))
+        self.key = '{}.{}.{}'.format(time.time(), random.random(), id(self))
 
     _ram_storage = ZODB.MappingStorage.MappingStorage()
     _ram_db = ZODB.DB(_ram_storage)
@@ -393,13 +374,13 @@ def _getData(self):
     data = property(_getData, None)
 
     def sweep(self):
-        super(RAMSessionDataContainer, self).sweep()
+        super().sweep()
         self._ram_db.pack(time.time())
 
 
 @zope.interface.implementer(ISession)
 @zope.component.adapter(IRequest)
-class Session(object):
+class Session:
     """
     Default implementation of  `zope.session.interfaces.ISession`
     """

src/zope/session/tests.py

@@ -118,38 +118,14 @@ def testSessionIterationBug(self):
 
 def test_suite():
     import doctest
-    import re
-
-    from zope.testing import renormalizing
-
-    checker = renormalizing.RENormalizing([
-        # Python 3 strings remove the "u".
-        (re.compile("u('.*?')"),
-         r"\1"),
-        (re.compile('u(".*?")'),
-         r"\1"),
-        # Python 3 bytes add a "b".
-        (re.compile("b('.*?')"),
-         r"\1"),
-        (re.compile('b(".*?")'),
-         r"\1"),
-        # Python 3 adds module name to exceptions.
-        (re.compile("zope.session.http.MissingClientIdException"),
-         r"MissingClientIdException"),
-    ])
+
     flags = doctest.NORMALIZE_WHITESPACE | doctest.ELLIPSIS
     suite = unittest.defaultTestLoader.loadTestsFromName(__name__)
 
     suite.addTest(doctest.DocTestSuite(
         'zope.session.session',
-        checker=checker,
         tearDown=tearDownTransaction))
     suite.addTest(doctest.DocTestSuite(
         'zope.session.http',
-        checker=checker,
         optionflags=flags))
     return suite
-
-
-if __name__ == '__main__':
-    unittest.main()