Merge pull request #480 from MITx/feature/victor/policy-dirs

Feature/victor/policy dirs

common/djangoapps/student/views.py

@@ -140,7 +140,20 @@ def dashboard(request):
     if not user.is_active:
         message = render_to_string('registration/activate_account_notice.html', {'email': user.email})
 
-    context = {'courses': courses, 'message': message}
+
+    # Global staff can see what courses errored on their dashboard
+    staff_access = False
+    errored_courses = {}
+    if has_access(user, 'global', 'staff'):
+        # Show any courses that errored on load
+        staff_access = True
+        errored_courses = modulestore().get_errored_courses()
+
+    context = {'courses': courses,
+               'message': message,
+               'staff_access': staff_access,
+               'errored_courses': errored_courses,}
+
     return render_to_response('dashboard.html', context)
 
 

common/lib/xmodule/xmodule/course_module.py

@@ -18,7 +18,7 @@ class CourseDescriptor(SequenceDescriptor):
     class Textbook:
         def __init__(self, title, book_url):
             self.title = title
-            self.book_url = book_url 
+            self.book_url = book_url
             self.table_of_contents = self._get_toc_from_s3()
 
         @classmethod
@@ -30,11 +30,11 @@ class CourseDescriptor(SequenceDescriptor):
             return self.table_of_contents
 
         def _get_toc_from_s3(self):
-            '''
+            """
             Accesses the textbook's table of contents (default name "toc.xml") at the URL self.book_url
 
             Returns XML tree representation of the table of contents
-            '''
+            """
             toc_url = self.book_url + 'toc.xml'
 
             # Get the table of contents from S3
@@ -72,6 +72,22 @@ class CourseDescriptor(SequenceDescriptor):
         self.enrollment_start = self._try_parse_time("enrollment_start")
         self.enrollment_end = self._try_parse_time("enrollment_end")
 
+        # NOTE: relies on the modulestore to call set_grading_policy() right after
+        # init.  (Modulestore is in charge of figuring out where to load the policy from)
+
+
+    def set_grading_policy(self, policy_str):
+        """Parse the policy specified in policy_str, and save it"""
+        try:
+            self._grading_policy = load_grading_policy(policy_str)
+        except:
+            self.system.error_tracker("Failed to load grading policy")
+            # Setting this to an empty dictionary will lead to errors when
+            # grading needs to happen, but should allow course staff to see
+            # the error log.
+            self._grading_policy = {}
+
+
     @classmethod
     def definition_from_xml(cls, xml_object, system):
         textbooks = []
@@ -87,25 +103,11 @@ class CourseDescriptor(SequenceDescriptor):
 
     @property
     def grader(self):
-        return self.__grading_policy['GRADER']
+        return self._grading_policy['GRADER']
 
     @property
     def grade_cutoffs(self):
-        return self.__grading_policy['GRADE_CUTOFFS']
-
-    @lazyproperty
-    def __grading_policy(self):
-        policy_string = ""
-
-        try:
-            with self.system.resources_fs.open("grading_policy.json") as grading_policy_file:
-                policy_string = grading_policy_file.read()
-        except (IOError, ResourceNotFoundError):
-            log.warning("Unable to load course settings file from grading_policy.json in course " + self.id)
-
-        grading_policy = load_grading_policy(policy_string)
-
-        return grading_policy
+        return self._grading_policy['GRADE_CUTOFFS']
 
     @lazyproperty
     def grading_context(self):

common/lib/xmodule/xmodule/graders.py

 import abc
 import json
 import logging
+import sys
 
 from collections import namedtuple
 
@@ -14,11 +15,11 @@ def load_grading_policy(course_policy_string):
     """
     This loads a grading policy from a string (usually read from a file),
     which can be a JSON object or an empty string.
-    
+
     The JSON object can have the keys GRADER and GRADE_CUTOFFS. If either is
     missing, it reverts to the default.
     """
-    
+
     default_policy_string = """
     {
         "GRADER" : [
@@ -56,7 +57,7 @@ def load_grading_policy(course_policy_string):
         }
     }
     """
-    
+
     # Load the global settings as a dictionary
     grading_policy = json.loads(default_policy_string)
 
@@ -64,15 +65,15 @@ def load_grading_policy(course_policy_string):
     course_policy = {}
     if course_policy_string:
         course_policy = json.loads(course_policy_string)
-    
+
     # Override any global settings with the course settings
     grading_policy.update(course_policy)
 
     # Here is where we should parse any configurations, so that we can fail early
     grading_policy['GRADER'] = grader_from_conf(grading_policy['GRADER'])
-    
+
     return grading_policy
-    
+
 
 def aggregate_scores(scores, section_name="summary"):
     """
@@ -130,9 +131,11 @@ def grader_from_conf(conf):
                 raise ValueError("Configuration has no appropriate grader class.")
 
         except (TypeError, ValueError) as error:
-            errorString = "Unable to parse grader configuration:\n    " + str(subgraderconf) + "\n    Error was:\n    " + str(error)
-            log.critical(errorString)
-            raise ValueError(errorString)
+            # Add info and re-raise
+            msg = ("Unable to parse grader configuration:\n    " +
+                   str(subgraderconf) +
+                   "\n    Error was:\n    " + str(error))
+            raise ValueError(msg), None, sys.exc_info()[2]
 
     return WeightedSubsectionsGrader(subgraders)
 

common/lib/xmodule/xmodule/modulestore/xml.py

@@ -4,16 +4,17 @@ import os
 import re
 
 from collections import defaultdict
+from cStringIO import StringIO
 from fs.osfs import OSFS
 from importlib import import_module
 from lxml import etree
 from lxml.html import HtmlComment
 from path import path
+
 from xmodule.errortracker import ErrorLog, make_error_tracker
-from xmodule.x_module import XModuleDescriptor, XMLParsingSystem
 from xmodule.course_module import CourseDescriptor
 from xmodule.mako_module import MakoDescriptorSystem
-from cStringIO import StringIO
+from xmodule.x_module import XModuleDescriptor, XMLParsingSystem
 
 from . import ModuleStoreBase, Location
 from .exceptions import ItemNotFoundError
@@ -134,12 +135,12 @@ class XMLModuleStore(ModuleStoreBase):
         self.data_dir = path(data_dir)
         self.modules = defaultdict(dict)  # course_id -> dict(location -> XModuleDescriptor)
         self.courses = {}  # course_dir -> XModuleDescriptor for the course
+        self.errored_courses = {}  # course_dir -> errorlog, for dirs that failed to load
 
         if default_class is None:
             self.default_class = None
         else:
             module_path, _, class_name = default_class.rpartition('.')
-            #log.debug('module_path = %s' % module_path)
             class_ = getattr(import_module(module_path), class_name)
             self.default_class = class_
 
@@ -162,18 +163,27 @@ class XMLModuleStore(ModuleStoreBase):
         '''
         Load a course, keeping track of errors as we go along.
         '''
+        # Special-case code here, since we don't have a location for the
+        # course before it loads.
+        # So, make a tracker to track load-time errors, then put in the right
+        # place after the course loads and we have its location
+        errorlog = make_error_tracker()
+        course_descriptor = None
         try:
-            # Special-case code here, since we don't have a location for the
-            # course before it loads.
-            # So, make a tracker to track load-time errors, then put in the right
-            # place after the course loads and we have its location
-            errorlog = make_error_tracker()
             course_descriptor = self.load_course(course_dir, errorlog.tracker)
+        except Exception as e:
+            msg = "Failed to load course '{0}': {1}".format(course_dir, str(e))
+            log.exception(msg)
+            errorlog.tracker(msg)
+
+        if course_descriptor is not None:
             self.courses[course_dir] = course_descriptor
             self._location_errors[course_descriptor.location] = errorlog
-        except:
-            msg = "Failed to load course '%s'" % course_dir
-            log.exception(msg)
+        else:
+            # Didn't load course.  Instead, save the errors elsewhere.
+            self.errored_courses[course_dir] = errorlog
+
+
 
     def __unicode__(self):
         '''
@@ -202,6 +212,28 @@ class XMLModuleStore(ModuleStoreBase):
         return {}
 
 
+    def read_grading_policy(self, paths, tracker):
+        """Load a grading policy from the specified paths, in order, if it exists."""
+        # Default to a blank policy
+        policy_str = ""
+
+        for policy_path in paths:
+            if not os.path.exists(policy_path):
+                continue
+            log.debug("Loading grading policy from {0}".format(policy_path))
+            try:
+                with open(policy_path) as grading_policy_file:
+                    policy_str = grading_policy_file.read()
+                    # if we successfully read the file, stop looking at backups
+                    break
+            except (IOError):
+                msg = "Unable to load course settings file from '{0}'".format(policy_path)
+                tracker(msg)
+                log.warning(msg)
+
+        return policy_str
+
+
     def load_course(self, course_dir, tracker):
         """
         Load a course into this module store
@@ -242,9 +274,16 @@ class XMLModuleStore(ModuleStoreBase):
                 course = course_dir
 
             url_name = course_data.get('url_name', course_data.get('slug'))
+            policy_dir = None
             if url_name:
-                policy_path = self.data_dir / course_dir / 'policies' / '{0}.json'.format(url_name)
+                policy_dir = self.data_dir / course_dir / 'policies' / url_name
+                policy_path = policy_dir / 'policy.json'
                 policy = self.load_policy(policy_path, tracker)
+
+                # VS[compat]: remove once courses use the policy dirs.
+                if policy == {}:
+                    old_policy_path = self.data_dir / course_dir / 'policies' / '{0}.json'.format(url_name)
+                    policy = self.load_policy(old_policy_path, tracker)
             else:
                 policy = {}
                 # VS[compat] : 'name' is deprecated, but support it for now...
@@ -268,6 +307,15 @@ class XMLModuleStore(ModuleStoreBase):
             # after we have the course descriptor.
             XModuleDescriptor.compute_inherited_metadata(course_descriptor)
 
+            # Try to load grading policy
+            paths = [self.data_dir / course_dir / 'grading_policy.json']
+            if policy_dir:
+                paths = [policy_dir / 'grading_policy.json'] + paths
+
+            policy_str = self.read_grading_policy(paths, tracker)
+            course_descriptor.set_grading_policy(policy_str)
+
+
             log.debug('========> Done with course import from {0}'.format(course_dir))
             return course_descriptor
 
@@ -318,6 +366,12 @@ class XMLModuleStore(ModuleStoreBase):
         """
         return self.courses.values()
 
+    def get_errored_courses(self):
+        """
+        Return a dictionary of course_dir -> [(msg, exception_str)], for each
+        course_dir where course loading failed.
+        """
+        return dict( (k, self.errored_courses[k].errors) for k in self.errored_courses)
 
     def create_item(self, location):
         raise NotImplementedError("XMLModuleStores are read-only")

common/lib/xmodule/xmodule/tests/test_import.py

@@ -233,6 +233,9 @@ class ImportTestCase(unittest.TestCase):
         self.assertEqual(toy_ch.display_name, "Overview")
         self.assertEqual(two_toys_ch.display_name, "Two Toy Overview")
 
+        # Also check that the grading policy loaded
+        self.assertEqual(two_toys.grade_cutoffs['C'], 0.5999)
+
 
     def test_definition_loading(self):
         """When two courses share the same org and course name and

common/test/data/two_toys/policies/TT_2012_Fall/grading_policy.json

+{
+  "GRADER" : [
+    {
+      "type" : "Homework",
+      "min_count" : 12,
+      "drop_count" : 2,
+      "short_label" : "HW",
+      "weight" : 0.15
+    },
+    {
+      "type" : "Lab",
+      "min_count" : 12,
+      "drop_count" : 2,
+      "category" : "Labs",
+      "weight" : 0.15
+    },
+    {
+      "type" : "Midterm",
+      "name" : "Midterm Exam",
+      "short_label" : "Midterm",
+      "weight" : 0.3
+    },
+    {
+      "type" : "Final",
+      "name" : "Final Exam",
+      "short_label" : "Final",
+      "weight" : 0.4
+    }
+  ],
+  "GRADE_CUTOFFS" : {
+    "A" : 0.87,
+    "B" : 0.7,
+    "C" : 0.5999
+  }
+}

lms/djangoapps/courseware/access.py

@@ -63,6 +63,9 @@ def has_access(user, obj, action):
     if isinstance(obj, Location):
         return _has_access_location(user, obj, action)
 
+    if isinstance(obj, basestring):
+        return _has_access_string(user, obj, action)
+
     # Passing an unknown object here is a coding error, so rather than
     # returning a default, complain.
     raise TypeError("Unknown object type in has_access(): '{0}'"
@@ -238,6 +241,30 @@ def _has_access_location(user, location, action):
     return _dispatch(checkers, action, user, location)
 
 
+def _has_access_string(user, perm, action):
+    """
+    Check if user has certain special access, specified as string.  Valid strings:
+
+    'global'
+
+    Valid actions:
+
+    'staff' -- global staff access.
+    """
+
+    def check_staff():
+        if perm != 'global':
+            debug("Deny: invalid permission '%s'", perm)
+            return False
+        return _has_global_staff_access(user)
+
+    checkers = {
+        'staff': check_staff
+        }
+
+    return _dispatch(checkers, action, user, perm)
+
+
 #####  Internal helper methods below
 
 def _dispatch(table, action, user, obj):
@@ -266,6 +293,15 @@ def _course_staff_group_name(location):
     """
     return 'staff_%s' % Location(location).course
 
+def _has_global_staff_access(user):
+    if user.is_staff:
+        debug("Allow: user.is_staff")
+        return True
+    else:
+        debug("Deny: not user.is_staff")
+        return False
+
+
 def _has_staff_access_to_location(user, location):
     '''
     Returns True if the given user has staff access to a location.  For now this

lms/djangoapps/courseware/courses.py

@@ -30,7 +30,6 @@ def get_course_by_id(course_id):
         raise Http404("Course not found.")
 
 
-
 def get_course_with_access(user, course_id, action):
     """
     Given a course_id, look up the corresponding course descriptor,

lms/templates/dashboard.html

@@ -107,6 +107,21 @@
       </section>
     % endif
 
+    % if staff_access and len(errored_courses) > 0:
+      <div id="course-errors">
+        <h2>Course-loading errors</h2>
+
+      % for course_dir, errors in errored_courses.items():
+         <h3>${course_dir | h}</h3>
+             <ul>
+           % for (msg, err) in errors:
+               <li>${msg}
+                 <ul><li><pre>${err}</pre></li></ul>
+               </li>
+           % endfor
+             </ul>
+      % endfor
+    % endif
   </section>
 </section>