Merge pull request #21105 from edx/INCR-434

INCR-434 python3 compatibility

lms/djangoapps/courseware/__init__.py

 #pylint: disable=missing-docstring
+from __future__ import absolute_import
+
 import warnings
 
 if __name__ == 'courseware':

lms/djangoapps/courseware/access.py

@@ -10,33 +10,34 @@ Note: The access control logic in this file does NOT check for enrollment in
   If enrollment is to be checked, use get_course_with_access in courseware.courses.
   It is a wrapper around has_access that additionally checks for enrollment.
 """
+from __future__ import absolute_import
+
 import logging
 from datetime import datetime
 
+import six
 from django.conf import settings
 from django.contrib.auth.models import AnonymousUser
-from pytz import UTC
 from opaque_keys.edx.keys import CourseKey, UsageKey
+from pytz import UTC
 from six import text_type
 from xblock.core import XBlock
 
 from courseware.access_response import (
+    IncorrectPartitionGroupError,
     MilestoneAccessError,
     MobileAvailabilityError,
-    VisibilityError,
+    NoAllowedPartitionGroupsError,
+    VisibilityError
 )
 from courseware.access_utils import (
     ACCESS_DENIED,
     ACCESS_GRANTED,
     adjust_start_date,
+    check_course_open_for_learner,
     check_start_date,
     debug,
-    in_preview_mode,
-    check_course_open_for_learner,
-)
-from courseware.access_response import (
-    NoAllowedPartitionGroupsError,
-    IncorrectPartitionGroupError,
+    in_preview_mode
 )
 from courseware.masquerade import get_masquerade_role, is_masquerading_as_student
 from lms.djangoapps.ccx.custom_exception import CCXLocatorValidationException
@@ -162,7 +163,7 @@ def has_access(user, action, obj, course_key=None):
     if isinstance(obj, UsageKey):
         return _has_access_location(user, action, obj, course_key)
 
-    if isinstance(obj, basestring):
+    if isinstance(obj, six.string_types):
         return _has_access_string(user, action, obj)
 
     # Passing an unknown object here is a coding error, so rather than
@@ -812,7 +813,12 @@ def _can_access_descriptor_with_milestones(user, descriptor, course_key):
         descriptor: the object being accessed
         course_key: key for the course for this descriptor
     """
-    if milestones_helpers.get_course_content_milestones(course_key, unicode(descriptor.location), 'requires', user.id):
+    if milestones_helpers.get_course_content_milestones(
+        course_key,
+        six.text_type(descriptor.location),
+        'requires',
+        user.id
+    ):
         debug("Deny: user has not completed all milestones for content")
         return ACCESS_DENIED
     else:

lms/djangoapps/courseware/access_response.py

@@ -2,6 +2,8 @@
 This file contains all the classes used by has_access for error handling
 """
 
+from __future__ import absolute_import
+
 from django.utils.translation import ugettext as _
 
 from xmodule.course_metadata_utils import DEFAULT_START_DATE

lms/djangoapps/courseware/access_utils.py

@@ -3,6 +3,8 @@ Simple utility functions for computing access.
 It allows us to share code between access.py and block transformers.
 """
 
+from __future__ import absolute_import
+
 from datetime import datetime, timedelta
 from logging import getLogger
 
@@ -11,10 +13,7 @@ from django.utils.translation import ugettext as _
 from pytz import UTC
 
 from courseware.access_response import AccessResponse, StartDateError
-from courseware.masquerade import (
-    get_course_masquerade,
-    is_masquerading_as_student
-)
+from courseware.masquerade import get_course_masquerade, is_masquerading_as_student
 from openedx.core.djangoapps.util.user_messages import PageLevelMessages
 from openedx.core.djangolib.markup import HTML
 from openedx.features.course_experience import COURSE_PRE_START_ACCESS_FLAG

lms/djangoapps/courseware/courseware_access_exception.py

 """
 This file contains the exception used in courseware access
 """
+from __future__ import absolute_import
+
 from django.http import Http404
 
 

lms/djangoapps/courseware/field_overrides.py

@@ -14,10 +14,13 @@ package and is used to wrap the `authored_data` when constructing an
 `LmsFieldData`.  This means overrides will be in effect for all scopes covered
 by `authored_data`, e.g. course content and settings stored in Mongo.
 """
+from __future__ import absolute_import
+
 import threading
 from abc import ABCMeta, abstractmethod
 from contextlib import contextmanager
 
+import six
 from django.conf import settings
 from edx_django_utils.cache import DEFAULT_REQUEST_CACHE
 from xblock.field_data import FieldData
@@ -91,7 +94,7 @@ def overrides_disabled():
     return bool(_OVERRIDES_DISABLED.disabled)
 
 
-class FieldOverrideProvider(object):
+class FieldOverrideProvider(six.with_metaclass(ABCMeta, object)):
     """
     Abstract class which defines the interface that a `FieldOverrideProvider`
     must provide.  In general, providers should derive from this class, but
@@ -102,7 +105,6 @@ class FieldOverrideProvider(object):
     field overrides. To set overrides, there will be a domain specific API for
     the concrete override implementation being used.
     """
-    __metaclass__ = ABCMeta
 
     def __init__(self, user, fallback_field_data):
         self.user = user
@@ -187,7 +189,7 @@ class OverrideFieldData(FieldData):
         if course is None:
             cache_key = ENABLED_OVERRIDE_PROVIDERS_KEY.format(course_id='None')
         else:
-            cache_key = ENABLED_OVERRIDE_PROVIDERS_KEY.format(course_id=unicode(course.id))
+            cache_key = ENABLED_OVERRIDE_PROVIDERS_KEY.format(course_id=six.text_type(course.id))
         enabled_providers = request_cache.data.get(cache_key, NOTSET)
         if enabled_providers == NOTSET:
             enabled_providers = tuple(
@@ -234,7 +236,7 @@ class OverrideFieldData(FieldData):
             # If this is an inheritable field and an override is set above,
             # then we want to return False here, so the field_data uses the
             # override and not the original value for this block.
-            inheritable = InheritanceMixin.fields.keys()
+            inheritable = list(InheritanceMixin.fields.keys())  # pylint: disable=no-member
             if name in inheritable:
                 for ancestor in _lineage(block):
                     if self.get_override(ancestor, name) is not NOTSET:
@@ -249,7 +251,7 @@ class OverrideFieldData(FieldData):
         # The `default` method is overloaded by the field storage system to
         # also handle inheritance.
         if self.providers and not overrides_disabled():
-            inheritable = InheritanceMixin.fields.keys()
+            inheritable = list(InheritanceMixin.fields.keys())  # pylint: disable=no-member
             if name in inheritable:
                 for ancestor in _lineage(block):
                     value = self.get_override(ancestor, name)
@@ -294,7 +296,7 @@ class OverrideModulestoreFieldData(OverrideFieldData):
         Arguments:
             block: An XBlock
         """
-        course_id = unicode(block.location.course_key)
+        course_id = six.text_type(block.location.course_key)
         cache_key = ENABLED_MODULESTORE_OVERRIDE_PROVIDERS_KEY.format(course_id=course_id)
 
         request_cache = DEFAULT_REQUEST_CACHE

lms/djangoapps/courseware/masquerade.py

@@ -4,9 +4,11 @@ Allow course staff to see a student or staff view of courseware.
 Which kind of view has been selected is stored in the session state.
 '''
 
-import logging
+from __future__ import absolute_import
 
+import logging
 from datetime import datetime
+
 from django.conf import settings
 from django.contrib.auth.decorators import login_required
 from django.contrib.auth.models import User

lms/djangoapps/courseware/tabs.py

@@ -2,11 +2,15 @@
 This module is essentially a broker to xmodule/tabs.py -- it was originally introduced to
 perform some LMS-specific tab display gymnastics for the Entrance Exams feature
 """
-from courseware.access import has_access
-from courseware.entrance_exams import user_can_skip_entrance_exam
+from __future__ import absolute_import
+
+import six
 from django.conf import settings
 from django.utils.translation import ugettext as _
 from django.utils.translation import ugettext_noop
+
+from courseware.access import has_access
+from courseware.entrance_exams import user_can_skip_entrance_exam
 from openedx.core.lib.course_tabs import CourseTabPluginManager
 from openedx.features.course_experience import UNIFIED_COURSE_TAB_FLAG, default_course_url_name
 from student.models import CourseEnrollment
@@ -291,7 +295,7 @@ class SingleTextbookTab(CourseTab):
     def __init__(self, name, tab_id, view_name, index):
         def link_func(course, reverse_func, index=index):
             """ Constructs a link for textbooks from a view name, a course, and an index. """
-            return reverse_func(view_name, args=[unicode(course.id), index])
+            return reverse_func(view_name, args=[six.text_type(course.id), index])
 
         tab_dict = dict()
         tab_dict['name'] = name

lms/djangoapps/courseware/url_helpers.py

 """
 Module to define url helpers functions
 """
-from urllib import urlencode
+from __future__ import absolute_import
 
+import six
 from django.urls import reverse
+from six.moves.urllib.parse import urlencode  # pylint: disable=import-error
 
 from xmodule.modulestore.django import modulestore
 from xmodule.modulestore.search import navigation_index, path_to_location
@@ -32,13 +34,13 @@ def get_redirect_url(course_key, usage_key):
     # args provided by the redirect.
     # Rely on index to do all error handling and access control.
     if chapter is None:
-        redirect_url = reverse('courseware', args=(unicode(course_key), ))
+        redirect_url = reverse('courseware', args=(six.text_type(course_key), ))
     elif section is None:
-        redirect_url = reverse('courseware_chapter', args=(unicode(course_key), chapter))
+        redirect_url = reverse('courseware_chapter', args=(six.text_type(course_key), chapter))
     elif position is None:
         redirect_url = reverse(
             'courseware_section',
-            args=(unicode(course_key), chapter, section)
+            args=(six.text_type(course_key), chapter, section)
         )
     else:
         # Here we use the navigation_index from the position returned from
@@ -46,7 +48,7 @@ def get_redirect_url(course_key, usage_key):
         # moment
         redirect_url = reverse(
             'courseware_position',
-            args=(unicode(course_key), chapter, section, navigation_index(position))
+            args=(six.text_type(course_key), chapter, section, navigation_index(position))
         )
-    redirect_url += "?{}".format(urlencode({'activate_block_id': unicode(final_target_id)}))
+    redirect_url += "?{}".format(urlencode({'activate_block_id': six.text_type(final_target_id)}))
     return redirect_url