Some changes from code review.

lms/djangoapps/courseware/decorators.py

+from functools import wraps
+
 from django.http import Http404
 
 from xmodule.course_module import CourseDescriptor
 from xmodule.modulestore.django import modulestore
 
+
 def check_course(course_must_be_open=True, course_required=True):
     """
     This is a decorator for views that are within a course.
@@ -14,11 +17,26 @@ def check_course(course_must_be_open=True, course_required=True):
     If the course has not started, it raises a 404. This check
     can be skipped by setting course_must_be_open to False.
     
-    If course_required is False, course_id is not required. If
+    Usually, a 404 will be raised if a course is not found. This
+    behavior can be overrided by setting course_required to false.
+    When course_required is False, course_id is not required. If
     course_id is still provided, but is None, course will be
     set to None.
+    
+    Usage
+    This wrapper would be used on a function that has the following
+    entry in urls.py:
+    
+    url(r'^courses/(?P<course_id>[^/]+/[^/]+/[^/]+)/book$', 'staticbook.views.index'),
+     
+    Where staticbook.views.index has the following parameters:
+    
+    @check_course
+    def index(request, course):
+        # Notice that the parameter is course, not course_id
     """
     def inner_check_course(function):
+        @wraps(function)
         def wrapped_function(*args, **kwargs):
             if course_required or 'course_id' in kwargs:
                 course_id = kwargs['course_id']
@@ -42,7 +60,7 @@ def check_course(course_must_be_open=True, course_required=True):
         
     # If no arguments were passed to the decorator, the function itself
     # will be in course_must_be_open
-    if hasattr(course_must_be_open, '__call__'):
+    if callable(course_must_be_open):
         function = course_must_be_open
         course_must_be_open = True
         return inner_check_course(function)

lms/djangoapps/courseware/views.py

@@ -17,7 +17,7 @@ from models import StudentModuleCache
 from student.models import UserProfile
 from multicourse import multicourse_settings
 
-#from util.cache import cache #TODO: Where did this go? lib/util/cache no longer exists
+from util.cache import cache
 from student.models import UserTestGroup
 from courseware import grades
 from courseware.decorators import check_course