Merge branch 'master' into pbaratta/calc-tests

.gitignore

@@ -26,6 +26,7 @@ Gemfile.lock
 conf/locale/en/LC_MESSAGES/*.po
 !messages.po
 lms/static/sass/*.css
+lms/static/sass/application.scss
 cms/static/sass/*.css
 lms/lib/comment_client/python
 nosetests.xml

.reviewboardrc

+REVIEWBOARD_URL = "https://rbcommons.com/s/edx/"
+GUESS_FIELDS = True

cms/djangoapps/contentstore/views/component.py

@@ -42,7 +42,7 @@ COMPONENT_TYPES = ['customtag', 'discussion', 'html', 'problem', 'video']
 
 OPEN_ENDED_COMPONENT_TYPES = ["combinedopenended", "peergrading"]
 NOTE_COMPONENT_TYPES = ['notes']
-ADVANCED_COMPONENT_TYPES = ['annotatable' + 'word_cloud'] + OPEN_ENDED_COMPONENT_TYPES + NOTE_COMPONENT_TYPES
+ADVANCED_COMPONENT_TYPES = ['annotatable', 'word_cloud'] + OPEN_ENDED_COMPONENT_TYPES + NOTE_COMPONENT_TYPES
 ADVANCED_COMPONENT_CATEGORY = 'advanced'
 ADVANCED_COMPONENT_POLICY_KEY = 'advanced_modules'
 

cms/envs/acceptance.py

@@ -2,6 +2,11 @@
 This config file extends the test environment configuration
 so that we can run the lettuce acceptance tests.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .test import *
 
 # You need to start the server in debug mode,
@@ -23,7 +28,7 @@ MODULESTORE_OPTIONS = {
 
 MODULESTORE = {
     'default': {
-        'ENGINE': 'xmodule.modulestore.mongo.MongoModuleStore',
+        'ENGINE': 'xmodule.modulestore.mongo.DraftMongoModuleStore',
         'OPTIONS': MODULESTORE_OPTIONS
     },
     'direct': {

cms/envs/aws.py

 """
 This is the default template for our main set of AWS servers.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 import json
 
 from .common import *

cms/envs/common.py

@@ -19,6 +19,10 @@ Longer TODO:
    multiple sites, but we do need a way to map their data assets.
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 import sys
 import lms.envs.common
 from path import path

cms/envs/dev.py

 """
 This config file runs the simplest dev environment"""
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 from logsettings import get_logger_config
 

cms/envs/dev_ike.py

+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 # dev environment for ichuang/mit
 
 # FORCE_SCRIPT_NAME = '/cms'

cms/envs/dev_with_worker.py

@@ -8,6 +8,10 @@ The worker can be executed using:
 django_admin.py celery worker
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from dev import *
 
 ################################# CELERY ######################################

cms/envs/jasmine.py

@@ -2,6 +2,10 @@
 This configuration is used for running jasmine tests
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .test import *
 from logsettings import get_logger_config
 

cms/envs/test.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 import os
 from path import path

cms/static/sass/_mixins-inherited.scss

@@ -5,6 +5,12 @@
 // talbs: we need to slowly ween ourselves off of these
 // ====================
 
+
+// line-height (old way)
+@function lh($amount: 1) {
+  @return $body-line-height * $amount;
+}
+
 // inherited - vertical and horizontal centering
 @mixin vertically-and-horizontally-centered ($height, $width) {
   left: 50%;

cms/static/sass/elements/_typography.scss

@@ -11,54 +11,54 @@
 .t-title1 {
   @extend .t-title;
   @include font-size(60);
-  @include lh(60);
+  @include line-height(60);
 }
 
 .t-title2 {
   @extend .t-title;
   @include font-size(48);
-  @include lh(48);
+  @include line-height(48);
 }
 
 .t-title3 {
   @include font-size(36);
-  @include lh(36);
+  @include line-height(36);
 }
 
 .t-title4 {
   @extend .t-title;
   @include font-size(24);
-  @include lh(24);
+  @include line-height(24);
 }
 
 .t-title5 {
   @extend .t-title;
   @include font-size(18);
-  @include lh(18);
+  @include line-height(18);
 }
 
 .t-title6 {
   @extend .t-title;
   @include font-size(16);
-  @include lh(16);
+  @include line-height(16);
 }
 
 .t-title7 {
   @extend .t-title;
   @include font-size(14);
-  @include lh(14);
+  @include line-height(14);
 }
 
 .t-title8 {
   @extend .t-title;
   @include font-size(12);
-  @include lh(12);
+  @include line-height(12);
 }
 
 .t-title9 {
   @extend .t-title;
   @include font-size(11);
-  @include lh(11);
+  @include line-height(11);
 }
 
 // ====================
@@ -71,31 +71,31 @@
 .t-copy-base {
   @extend .t-copy;
   @include font-size(16);
-  @include lh(16);
+  @include line-height(16);
 }
 
 .t-copy-lead1 {
   @extend .t-copy;
   @include font-size(18);
-  @include lh(18);
+  @include line-height(18);
 }
 
 .t-copy-lead2 {
   @extend .t-copy;
   @include font-size(24);
-  @include lh(24);
+  @include line-height(24);
 }
 
 .t-copy-sub1 {
   @extend .t-copy;
   @include font-size(14);
-  @include lh(14);
+  @include line-height(14);
 }
 
 .t-copy-sub2 {
   @extend .t-copy;
   @include font-size(12);
-  @include lh(12);
+  @include line-height(12);
 }
 
 // ====================
@@ -103,22 +103,22 @@
 // actions/labels
 .t-action1 {
   @include font-size(18);
-  @include lh(18);
+  @include line-height(18);
 }
 
 .t-action2 {
   @include font-size(16);
-  @include lh(16);
+  @include line-height(16);
 }
 
 .t-action3 {
   @include font-size(14);
-  @include lh(14);
+  @include line-height(14);
 }
 
 .t-action4 {
   @include font-size(12);
-  @include lh(12);
+  @include line-height(12);
 }
 
 

common/lib/calc/setup.py

@@ -2,7 +2,7 @@ from setuptools import setup
 
 setup(
     name="calc",
-    version="0.1",
+    version="0.1.1",
     py_modules=["calc"],
     install_requires=[
         "pyparsing==1.5.6",

common/lib/capa/capa/capa_problem.py

@@ -475,12 +475,11 @@ class LoncapaProblem(object):
                 msg = "Error while executing script code: %s" % str(err).replace('<', '&lt;')
                 raise responsetypes.LoncapaProblemError(msg)
 
-        # store code source in context
+        # Store code source in context, along with the Python path needed to run it correctly.
         context['script_code'] = all_code
+        context['python_path'] = python_path
         return context
 
-
-
     def _extract_html(self, problemtree):  # private
         '''
         Main (private) function which converts Problem XML tree to HTML.

common/lib/capa/capa/responsetypes.py

@@ -286,7 +286,7 @@ class LoncapaResponse(object):
             }
 
             try:
-                safe_exec.safe_exec(code, globals_dict)
+                safe_exec.safe_exec(code, globals_dict, python_path=self.context['python_path'])
             except Exception as err:
                 msg = 'Error %s in evaluating hint function %s' % (err, hintfn)
                 msg += "\nSee XML source line %s" % getattr(
@@ -972,7 +972,7 @@ class CustomResponse(LoncapaResponse):
                             'ans': ans,
                         }
                         globals_dict.update(kwargs)
-                        safe_exec.safe_exec(code, globals_dict, cache=self.system.cache)
+                        safe_exec.safe_exec(code, globals_dict, python_path=self.context['python_path'])
                         return globals_dict['cfn_return']
                     return check_function
 

common/lib/capa/capa/safe_exec/tests/test_lazymod.py

@@ -39,6 +39,9 @@ class TestLazyMod(unittest.TestCase):
         self.assertEqual(hsv[0], 0.25)
 
     def test_dotted(self):
-        self.assertNotIn("email.utils", sys.modules)
-        email_utils = LazyModule("email.utils")
-        self.assertEqual(email_utils.quote('"hi"'), r'\"hi\"')
+        # wsgiref is a module with submodules that is not already imported.
+        # Any similar module would do. This test demonstrates that the module
+        # is not already im
+        self.assertNotIn("wsgiref.util", sys.modules)
+        wsgiref_util = LazyModule("wsgiref.util")
+        self.assertEqual(wsgiref_util.guess_scheme({}), "http")

common/lib/chem/setup.py

@@ -2,7 +2,7 @@ from setuptools import setup
 
 setup(
     name="chem",
-    version="0.1",
+    version="0.1.1",
     packages=["chem"],
     install_requires=[
         "pyparsing==1.5.6",

common/lib/sandbox-packages/setup.py

@@ -2,7 +2,7 @@ from setuptools import setup
 
 setup(
     name="sandbox-packages",
-    version="0.1",
+    version="0.1.1",
     packages=[
         "verifiers",
     ],

common/lib/xmodule/xmodule/combined_open_ended_module.py

@@ -8,7 +8,7 @@ from .x_module import XModule
 from xblock.core import Integer, Scope, String, Boolean, List
 from xmodule.open_ended_grading_classes.combined_open_ended_modulev1 import CombinedOpenEndedV1Module, CombinedOpenEndedV1Descriptor
 from collections import namedtuple
-from .fields import Date, StringyFloat
+from .fields import Date, StringyFloat, StringyInteger, StringyBoolean
 
 log = logging.getLogger("mitx.courseware")
 
@@ -49,19 +49,19 @@ class VersionInteger(Integer):
 
 class CombinedOpenEndedFields(object):
     display_name = String(help="Display name for this module", default="Open Ended Grading", scope=Scope.settings)
-    current_task_number = Integer(help="Current task that the student is on.", default=0, scope=Scope.user_state)
+    current_task_number = StringyInteger(help="Current task that the student is on.", default=0, scope=Scope.user_state)
     task_states = List(help="List of state dictionaries of each task within this module.", scope=Scope.user_state)
     state = String(help="Which step within the current task that the student is on.", default="initial",
                    scope=Scope.user_state)
-    student_attempts = Integer(help="Number of attempts taken by the student on this problem", default=0,
+    student_attempts = StringyInteger(help="Number of attempts taken by the student on this problem", default=0,
                                scope=Scope.user_state)
-    ready_to_reset = Boolean(help="If the problem is ready to be reset or not.", default=False,
+    ready_to_reset = StringyBoolean(help="If the problem is ready to be reset or not.", default=False,
                              scope=Scope.user_state)
-    attempts = Integer(help="Maximum number of attempts that a student is allowed.", default=1, scope=Scope.settings)
-    is_graded = Boolean(help="Whether or not the problem is graded.", default=False, scope=Scope.settings)
-    accept_file_upload = Boolean(help="Whether or not the problem accepts file uploads.", default=False,
+    attempts = StringyInteger(help="Maximum number of attempts that a student is allowed.", default=1, scope=Scope.settings)
+    is_graded = StringyBoolean(help="Whether or not the problem is graded.", default=False, scope=Scope.settings)
+    accept_file_upload = StringyBoolean(help="Whether or not the problem accepts file uploads.", default=False,
                                  scope=Scope.settings)
-    skip_spelling_checks = Boolean(help="Whether or not to skip initial spelling checks.", default=True,
+    skip_spelling_checks = StringyBoolean(help="Whether or not to skip initial spelling checks.", default=True,
                                    scope=Scope.settings)
     due = Date(help="Date that this problem is due by", default=None, scope=Scope.settings)
     graceperiod = String(help="Amount of time after the due date that submissions will be accepted", default=None,

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

@@ -290,7 +290,6 @@ class XMLModuleStore(ModuleStoreBase):
         if course_dirs is None:
             course_dirs = sorted([d for d in os.listdir(self.data_dir) if
                                   os.path.exists(self.data_dir / d / "course.xml")])
-
         for course_dir in course_dirs:
             self.try_load_course(course_dir)
 

common/lib/xmodule/xmodule/open_ended_grading_classes/controller_query_service.py

@@ -6,7 +6,7 @@ log = logging.getLogger(__name__)
 
 class ControllerQueryService(GradingService):
     """
-    Interface to staff grading backend.
+    Interface to controller query backend.
     """
 
     def __init__(self, config, system):
@@ -77,6 +77,50 @@ class ControllerQueryService(GradingService):
         return response
 
 
+class MockControllerQueryService(object):
+    """
+    Mock controller query service for testing
+    """
+
+    def __init__(self, config, system):
+        pass
+
+    def check_if_name_is_unique(self, **params):
+        """
+        Mock later if needed.  Stub function for now.
+        @param params:
+        @return:
+        """
+        pass
+
+    def check_for_eta(self, **params):
+        """
+        Mock later if needed.  Stub function for now.
+        @param params:
+        @return:
+        """
+        pass
+
+    def check_combined_notifications(self, **params):
+        combined_notifications = '{"flagged_submissions_exist": false, "version": 1, "new_student_grading_to_view": false, "success": true, "staff_needs_to_grade": false, "student_needs_to_peer_grade": true, "overall_need_to_check": true}'
+        return combined_notifications
+
+    def get_grading_status_list(self, **params):
+        grading_status_list = '{"version": 1, "problem_list": [{"problem_name": "Science Question -- Machine Assessed", "grader_type": "NA", "eta_available": true, "state": "Waiting to be Graded", "eta": 259200, "location": "i4x://MITx/oe101x/combinedopenended/Science_SA_ML"}, {"problem_name": "Humanities Question -- Peer Assessed", "grader_type": "NA", "eta_available": true, "state": "Waiting to be Graded", "eta": 259200, "location": "i4x://MITx/oe101x/combinedopenended/Humanities_SA_Peer"}], "success": true}'
+        return grading_status_list
+
+    def get_flagged_problem_list(self, **params):
+        flagged_problem_list = '{"version": 1, "success": false, "error": "No flagged submissions exist for course: MITx/oe101x/2012_Fall"}'
+        return flagged_problem_list
+
+    def take_action_on_flags(self, **params):
+        """
+        Mock later if needed.  Stub function for now.
+        @param params:
+        @return:
+        """
+        pass
+
 def convert_seconds_to_human_readable(seconds):
     if seconds < 60:
         human_string = "{0} seconds".format(seconds)

common/static/sass/_mixins.scss

@@ -8,7 +8,7 @@
 }
 
 // mixins - line height
-@mixin lh($fontSize: auto){
+@mixin line-height($fontSize: auto){
   line-height: ($fontSize*1.48) + px;
   line-height: (($fontSize/10)*1.48) + rem;
 }

lms/djangoapps/courseware/module_render.py

@@ -414,6 +414,11 @@ def modx_dispatch(request, dispatch, location, course_id):
            through the part before the first '?'.
       - location -- the module location. Used to look up the XModule instance
       - course_id -- defines the course context for this request.
+
+    Raises PermissionDenied if the user is not logged in. Raises Http404 if
+    the location and course_id do not identify a valid module, the module is
+    not accessible by the user, or the module raises NotFoundError. If the
+    module raises any other error, it will escape this function.
     '''
     # ''' (fix emacs broken parsing)
 
@@ -442,8 +447,19 @@ def modx_dispatch(request, dispatch, location, course_id):
                     return HttpResponse(json.dumps({'success': file_too_big_msg}))
             p[fileinput_id] = inputfiles
 
+    try:
+        descriptor = modulestore().get_instance(course_id, location)
+    except ItemNotFoundError:
+        log.warn(
+            "Invalid location for course id {course_id}: {location}".format(
+                course_id=course_id,
+                location=location
+            )
+        )
+        raise Http404
+
     model_data_cache = ModelDataCache.cache_for_descriptor_descendents(course_id,
-        request.user, modulestore().get_instance(course_id, location))
+        request.user, descriptor)
 
     instance = get_module(request.user, request, location, model_data_cache, course_id, grade_bucket_type='ajax')
     if instance is None:

lms/djangoapps/courseware/tests/test_module_render.py

@@ -69,19 +69,38 @@ class ModuleRenderTestCase(LoginEnrollmentTestCase):
                           json.dumps({'success': 'Submission aborted! Your file "%s" is too large (max size: %d MB)' %
                                       (inputfile.name, settings.STUDENT_FILEUPLOAD_MAX_SIZE / (1000 ** 2))}))
         mock_request_3 = MagicMock()
-        mock_request_3.POST.copy.return_value = {}
+        mock_request_3.POST.copy.return_value = {'position': 1}
         mock_request_3.FILES = False
         mock_request_3.user = UserFactory()
         inputfile_2 = Stub()
         inputfile_2.size = 1
         inputfile_2.name = 'name'
-        self.assertRaises(ItemNotFoundError, render.modx_dispatch,
-                          mock_request_3, 'dummy', self.location, 'toy')
-        self.assertRaises(Http404, render.modx_dispatch, mock_request_3, 'dummy',
-                          self.location, self.course_id)
-        mock_request_3.POST.copy.return_value = {'position': 1}
         self.assertIsInstance(render.modx_dispatch(mock_request_3, 'goto_position',
                                                    self.location, self.course_id), HttpResponse)
+        self.assertRaises(
+            Http404,
+            render.modx_dispatch,
+            mock_request_3,
+            'goto_position',
+            self.location,
+            'bad_course_id'
+        )
+        self.assertRaises(
+            Http404,
+            render.modx_dispatch,
+            mock_request_3,
+            'goto_position',
+            ['i4x', 'edX', 'toy', 'chapter', 'bad_location'],
+            self.course_id
+        )
+        self.assertRaises(
+            Http404,
+            render.modx_dispatch,
+            mock_request_3,
+            'bad_dispatch',
+            self.location,
+            self.course_id
+        )
 
     def test_get_score_bucket(self):
         self.assertEquals(render.get_score_bucket(0, 10), 'incorrect')

lms/djangoapps/django_comment_client/forum/views.py

@@ -174,6 +174,9 @@ def forum_form_discussion(request, course_id):
     try:
         unsafethreads, query_params = get_threads(request, course_id)   # This might process a search query
         threads = [utils.safe_content(thread) for thread in unsafethreads]
+    except (cc.utils.CommentClientMaintenanceError) as err:
+        log.warning("Forum is in maintenance mode")
+        return render_to_response('discussion/maintenance.html', {})
     except (cc.utils.CommentClientError, cc.utils.CommentClientUnknownError) as err:
         log.error("Error loading forum discussion threads: %s" % str(err))
         raise Http404

lms/djangoapps/notes/migrations/0001_initial.py

@@ -13,7 +13,7 @@ class Migration(SchemaMigration):
             ('id', self.gf('django.db.models.fields.AutoField')(primary_key=True)),
             ('user', self.gf('django.db.models.fields.related.ForeignKey')(to=orm['auth.User'])),
             ('course_id', self.gf('django.db.models.fields.CharField')(max_length=255, db_index=True)),
-            ('uri', self.gf('django.db.models.fields.CharField')(max_length=512, db_index=True)),
+            ('uri', self.gf('django.db.models.fields.CharField')(max_length=255, db_index=True)),
             ('text', self.gf('django.db.models.fields.TextField')(default='')),
             ('quote', self.gf('django.db.models.fields.TextField')(default='')),
             ('range_start', self.gf('django.db.models.fields.CharField')(max_length=2048)),
@@ -82,7 +82,7 @@ class Migration(SchemaMigration):
             'tags': ('django.db.models.fields.TextField', [], {'default': "''"}),
             'text': ('django.db.models.fields.TextField', [], {'default': "''"}),
             'updated': ('django.db.models.fields.DateTimeField', [], {'auto_now': 'True', 'db_index': 'True', 'blank': 'True'}),
-            'uri': ('django.db.models.fields.CharField', [], {'max_length': '512', 'db_index': 'True'}),
+            'uri': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'}),
             'user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']"})
         }
     }

lms/djangoapps/notes/models.py

@@ -9,7 +9,7 @@ import json
 class Note(models.Model):
     user = models.ForeignKey(User, db_index=True)
     course_id = models.CharField(max_length=255, db_index=True)
-    uri = models.CharField(max_length=512, db_index=True)
+    uri = models.CharField(max_length=255, db_index=True)
     text = models.TextField(default="")
     quote = models.TextField(default="")
     range_start = models.CharField(max_length=2048)  # xpath string

lms/djangoapps/open_ended_grading/views.py

@@ -21,6 +21,7 @@ import open_ended_notifications
 
 from xmodule.modulestore.django import modulestore
 from xmodule.modulestore import search
+from xmodule.modulestore.exceptions import ItemNotFoundError
 
 from django.http import HttpResponse, Http404, HttpResponseRedirect
 from mitxmako.shortcuts import render_to_string
@@ -30,10 +31,10 @@ log = logging.getLogger(__name__)
 system = ModuleSystem(
     ajax_url=None,
     track_function=None,
-    get_module = None,
+    get_module=None,
     render_template=render_to_string,
-    replace_urls = None,
-    xblock_model_data= {}
+    replace_urls=None,
+    xblock_model_data={}
 )
 controller_qs = ControllerQueryService(settings.OPEN_ENDED_GRADING_INTERFACE, system)
 
@@ -90,40 +91,61 @@ def staff_grading(request, course_id):
         'staff_access': True, })
 
 
+def find_peer_grading_module(course):
+    """
+    Given a course, finds the first peer grading module in it.
+    @param course: A course object.
+    @return: boolean found_module, string problem_url
+    """
+    #Reverse the base course url
+    base_course_url = reverse('courses')
+    found_module = False
+    problem_url = ""
+
+    #Get the course id and split it
+    course_id_parts = course.id.split("/")
+    log.info("COURSE ID PARTS")
+    log.info(course_id_parts)
+    #Get the peer grading modules currently in the course.  Explicitly specify the course id to avoid issues with different runs.
+    items = modulestore().get_items(['i4x', course_id_parts[0], course_id_parts[1], 'peergrading', None],
+                                    course_id=course.id)
+    #See if any of the modules are centralized modules (ie display info from multiple problems)
+    items = [i for i in items if not getattr(i, "use_for_single_location", True)]
+    #Get the first one
+    if len(items) > 0:
+        item_location = items[0].location
+        #Generate a url for the first module and redirect the user to it
+        problem_url_parts = search.path_to_location(modulestore(), course.id, item_location)
+        problem_url = generate_problem_url(problem_url_parts, base_course_url)
+        found_module = True
+
+    return found_module, problem_url
+
+
 @cache_control(no_cache=True, no_store=True, must_revalidate=True)
 def peer_grading(request, course_id):
     '''
-    Show a peer grading interface
+    When a student clicks on the "peer grading" button in the open ended interface, link them to a peer grading
+    xmodule in the course.
     '''
 
     #Get the current course
     course = get_course_with_access(request.user, course_id, 'load')
-    course_id_parts = course.id.split("/")
-    false_dict = [False, "False", "false", "FALSE"]
-
-    #Reverse the base course url
-    base_course_url = reverse('courses')
-    try:
-        #TODO:  This will not work with multiple runs of a course.  Make it work.  The last key in the Location passed
-        #to get_items is called revision.  Is this the same as run?
-        #Get the peer grading modules currently in the course
-        items = modulestore().get_items(['i4x', None, course_id_parts[1], 'peergrading', None])
-        #See if any of the modules are centralized modules (ie display info from multiple problems)
-        items = [i for i in items if getattr(i,"use_for_single_location", True) in false_dict]
-        #Get the first one
-        item_location = items[0].location
-        #Generate a url for the first module and redirect the user to it
-        problem_url_parts = search.path_to_location(modulestore(), course.id, item_location)
-        problem_url = generate_problem_url(problem_url_parts, base_course_url)
 
-        return HttpResponseRedirect(problem_url)
-    except:
+    found_module, problem_url = find_peer_grading_module(course)
+    if not found_module:
         #This is a student_facing_error
-        error_message = "Error with initializing peer grading.  Centralized module does not exist.  Please contact course staff."
+        error_message = """
+        Error with initializing peer grading.
+        There has not been a peer grading module created in the courseware that would allow you to grade others.
+        Please check back later for this.
+        """
         #This is a dev_facing_error
         log.exception(error_message + "Current course is: {0}".format(course_id))
         return HttpResponse(error_message)
 
+    return HttpResponseRedirect(problem_url)
+
 
 def generate_problem_url(problem_url_parts, base_course_url):
     """
@@ -145,7 +167,8 @@ def generate_problem_url(problem_url_parts, base_course_url):
 @cache_control(no_cache=True, no_store=True, must_revalidate=True)
 def student_problem_list(request, course_id):
     '''
-    Show a student problem list
+    Show a student problem list to a student.  Fetch the list from the grading controller server, get some metadata,
+    and then show it to the student.
     '''
     course = get_course_with_access(request.user, course_id, 'load')
     student_id = unique_id_for_user(request.user)
@@ -157,6 +180,7 @@ def student_problem_list(request, course_id):
     base_course_url = reverse('courses')
 
     try:
+        #Get list of all open ended problems that the grading server knows about
         problem_list_json = controller_qs.get_grading_status_list(course_id, unique_id_for_user(request.user))
         problem_list_dict = json.loads(problem_list_json)
         success = problem_list_dict['success']
@@ -166,8 +190,22 @@ def student_problem_list(request, course_id):
         else:
             problem_list = problem_list_dict['problem_list']
 
+        #A list of problems to remove (problems that can't be found in the course)
+        list_to_remove = []
         for i in xrange(0, len(problem_list)):
-            problem_url_parts = search.path_to_location(modulestore(), course.id, problem_list[i]['location'])
+            try:
+                #Try to load each problem in the courseware to get links to them
+                problem_url_parts = search.path_to_location(modulestore(), course.id, problem_list[i]['location'])
+            except ItemNotFoundError:
+                #If the problem cannot be found at the location received from the grading controller server, it has been deleted by the course author.
+                #Continue with the rest of the location to construct the list
+                error_message = "Could not find module for course {0} at location {1}".format(course.id,
+                                                                                              problem_list[i][
+                                                                                                  'location'])
+                log.error(error_message)
+                #Mark the problem for removal from the list
+                list_to_remove.append(i)
+                continue
             problem_url = generate_problem_url(problem_url_parts, base_course_url)
             problem_list[i].update({'actual_url': problem_url})
             eta_available = problem_list[i]['eta_available']
@@ -197,6 +235,8 @@ def student_problem_list(request, course_id):
         log.error("Problem with results from external grading service for open ended.")
         success = False
 
+    #Remove problems that cannot be found in the courseware from the list
+    problem_list = [problem_list[i] for i in xrange(0, len(problem_list)) if i not in list_to_remove]
     ajax_url = _reverse_with_slash('open_ended_problems', course_id)
 
     return render_to_response('open_ended_problems/open_ended_problems.html', {
@@ -300,7 +340,16 @@ def combined_notifications(request, course_id):
                 'description': description,
                 'alert_message': alert_message
             }
-            notification_list.append(notification_item)
+            #The open ended panel will need to link the "peer grading" button in the panel to a peer grading
+            #xmodule defined in the course.  This checks to see if the human name of the server notification
+            #that we are currently processing is "peer grading".  If it is, it looks for a peer grading
+            #module in the course.  If none exists, it removes the peer grading item from the panel.
+            if human_name == "Peer Grading":
+                found_module, problem_url = find_peer_grading_module(course)
+                if found_module:
+                    notification_list.append(notification_item)
+            else:
+                notification_list.append(notification_item)
 
     ajax_url = _reverse_with_slash('open_ended_notifications', course_id)
     combined_dict = {
@@ -311,9 +360,7 @@ def combined_notifications(request, course_id):
         'ajax_url': ajax_url,
     }
 
-    return render_to_response('open_ended_problems/combined_notifications.html',
-                              combined_dict
-    )
+    return render_to_response('open_ended_problems/combined_notifications.html', combined_dict)
 
 
 @cache_control(no_cache=True, no_store=True, must_revalidate=True)

lms/envs/acceptance.py

@@ -2,6 +2,11 @@
 This config file extends the test environment configuration
 so that we can run the lettuce acceptance tests.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .test import *
 
 # You need to start the server in debug mode,

lms/envs/aws.py

@@ -6,6 +6,11 @@ Common traits:
 * Use memcached, and cache-backed sessions
 * Use a MySQL 5.1 database
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 import json
 
 from .common import *
@@ -109,6 +114,11 @@ DEFAULT_FEEDBACK_EMAIL = ENV_TOKENS.get('DEFAULT_FEEDBACK_EMAIL', DEFAULT_FEEDBA
 ADMINS = ENV_TOKENS.get('ADMINS', ADMINS)
 SERVER_EMAIL = ENV_TOKENS.get('SERVER_EMAIL', SERVER_EMAIL)
 
+#Theme overrides
+THEME_NAME = ENV_TOKENS.get('THEME_NAME', None)
+if not THEME_NAME is None:
+    enable_theme(THEME_NAME)
+
 #Timezone overrides
 TIME_ZONE = ENV_TOKENS.get('TIME_ZONE', TIME_ZONE)
 

lms/envs/cms/acceptance.py

@@ -3,6 +3,11 @@ This config file is a copy of dev environment without the Debug
 Toolbar. I it suitable to run against acceptance tests.
 
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .dev import *
 
 #  REMOVE DEBUG TOOLBAR

lms/envs/cms/aws.py

@@ -2,6 +2,10 @@
 Settings for the LMS that runs alongside the CMS on AWS
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from ..aws import *
 
 with open(ENV_ROOT / "cms.auth.json") as auth_file:

lms/envs/cms/dev.py

@@ -2,6 +2,10 @@
 Settings for the LMS that runs alongside the CMS on AWS
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from ..dev import *
 
 MITX_FEATURES['AUTH_USE_MIT_CERTIFICATES'] = False

lms/envs/cms/preview_dev.py

@@ -2,6 +2,10 @@
 Settings for the LMS that runs alongside the CMS on AWS
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .dev import *
 
 MODULESTORE = {

lms/envs/common.py

@@ -18,6 +18,11 @@ Longer TODO:
 3. We need to handle configuration for multiple courses. This could be as
    multiple sites, but we do need a way to map their data assets.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 import sys
 import os
 
@@ -67,6 +72,7 @@ MITX_FEATURES = {
 
     'ENABLE_PSYCHOMETRICS': False,  	# real-time psychometrics (eg item response theory analysis in instructor dashboard)
 
+    'ENABLE_DJANGO_ADMIN_SITE': False,  # set true to enable django's admin site, even on prod (e.g. for course ops)
     'ENABLE_SQL_TRACKING_LOGS': False,
     'ENABLE_LMS_MIGRATION': False,
     'ENABLE_MANUAL_GIT_RELOAD': False,
@@ -105,6 +111,9 @@ MITX_FEATURES = {
 
     # Enable URL that shows information about the status of variuous services
     'ENABLE_SERVICE_STATUS': False,
+
+    # Toggle to indicate use of a custom theme
+    'USE_CUSTOM_THEME': False
 }
 
 # Used for A/B testing
@@ -162,12 +171,12 @@ MAKO_TEMPLATES['main'] = [PROJECT_ROOT / 'templates',
 
 # This is where Django Template lookup is defined. There are a few of these
 # still left lying around.
-TEMPLATE_DIRS = (
+TEMPLATE_DIRS = [
     PROJECT_ROOT / "templates",
     COMMON_ROOT / 'templates',
     COMMON_ROOT / 'lib' / 'capa' / 'capa' / 'templates',
     COMMON_ROOT / 'djangoapps' / 'pipeline_mako' / 'templates',
-)
+]
 
 TEMPLATE_CONTEXT_PROCESSORS = (
     'django.core.context_processors.request',
@@ -709,3 +718,31 @@ MKTG_URL_LINK_MAP = {
     'HONOR': 'honor',
     'PRIVACY': 'privacy_edx',
 }
+
+############################### THEME ################################
+def enable_theme(theme_name):
+    """
+    Enable the settings for a custom theme, whose files should be stored
+    in ENV_ROOT/themes/THEME_NAME (e.g., edx_all/themes/stanford).
+
+    The THEME_NAME setting should be configured separately since it can't
+    be set here (this function closes too early). An idiom for doing this
+    is:
+
+    THEME_NAME = "stanford"
+    enable_theme(THEME_NAME)
+    """
+    MITX_FEATURES['USE_CUSTOM_THEME'] = True
+
+    # Calculate the location of the theme's files
+    theme_root = ENV_ROOT / "themes" / theme_name
+
+    # Include the theme's templates in the template search paths
+    TEMPLATE_DIRS.append(theme_root / 'templates')
+    MAKO_TEMPLATES['main'].append(theme_root / 'templates')
+
+    # Namespace the theme's static files to 'themes/<theme_name>' to
+    # avoid collisions with default edX static files
+    STATICFILES_DIRS.append((u'themes/%s' % theme_name,
+                             theme_root / 'static'))
+

lms/envs/content.py

@@ -2,6 +2,11 @@
 These are debug machines used for content creators, so they're kind of a cross
 between dev machines and AWS machines.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .aws import *
 
 DEBUG = True

lms/envs/dev.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 from logsettings import get_logger_config
 

lms/envs/dev_edx4edx.py

@@ -8,6 +8,10 @@ sessions. Assumes structure:
         /log  # Where we're going to write log files
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 import socket
 
 if 'eecs1' in socket.gethostname():

lms/envs/dev_ike.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 from logsettings import get_logger_config
 from .dev import *

lms/envs/dev_int.py

@@ -9,6 +9,11 @@ following domains to 127.0.0.1 in your /etc/hosts file:
 Note that OS X has a bug where using *.local domains is excruciatingly slow, so
 use *.dev domains instead for local testing.
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .dev import *
 
 MITX_FEATURES['SUBDOMAIN_COURSE_LISTINGS'] = True

lms/envs/dev_mongo.py

 """
 This config file runs the dev environment, but with mongo as the datastore
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .dev import *
 
 GITHUB_REPO_ROOT = ENV_ROOT / "data"

lms/envs/dev_with_worker.py

@@ -8,6 +8,10 @@ The worker can be executed using:
 django_admin.py celery worker
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from dev import *
 
 ################################# CELERY ######################################

lms/envs/devgroups/courses.py

+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from ..dev import *
 
 CLASSES_TO_DBS = {

lms/envs/devgroups/h_cs50.py

+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .courses import *
 
 DATABASES = course_db_for('HarvardX/CS50x/2012')

lms/envs/devgroups/m_6002.py

+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .courses import *
 
 DATABASES = course_db_for('MITx/6.002x/2012_Fall')

lms/envs/devgroups/portal.py

@@ -2,6 +2,11 @@
 Note that for this to work at all, you must have memcached running (or you won't
 get shared sessions)
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from courses import *
 
 # Move this to a shared file later:

lms/envs/devplus.py

@@ -13,6 +13,11 @@ Dir structure:
         /log  # Where we're going to write log files
 
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .dev import *
 
 WIKI_ENABLED = True

lms/envs/discussionsettings.py

+
+# We intentionally define variables that aren't used
+# pylint: disable=W0614
+
 DISCUSSION_ALLOWED_UPLOAD_FILE_TYPES = ('.jpg', '.jpeg', '.gif', '.bmp', '.png', '.tiff')

lms/envs/edx4edx_aws.py

+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 # Settings for edx4edx production instance
 from .aws import *
 COURSE_NAME = "edx4edx"

lms/envs/jasmine.py

@@ -2,6 +2,10 @@
 This configuration is used for running jasmine tests
 """
 
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .test import *
 from logsettings import get_logger_config
 

lms/envs/static.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 from logsettings import get_logger_config
 

lms/envs/test.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 import os
 from path import path

lms/envs/test_ike.py

@@ -7,6 +7,11 @@ sessions. Assumes structure:
         /mitx # The location of this repo
         /log  # Where we're going to write log files
 """
+
+# We intentionally define lots of variables that aren't used, and
+# want to import all variables from base settings files
+# pylint: disable=W0401, W0614
+
 from .common import *
 from logsettings import get_logger_config
 import os

lms/lib/comment_client/utils.py

@@ -31,14 +31,9 @@ def merge_dict(dic1, dic2):
 def perform_request(method, url, data_or_params=None, *args, **kwargs):
     if data_or_params is None:
         data_or_params = {}
-    tags = [
-        "{k}:{v}".format(k=k, v=v)
-        for (k, v) in data_or_params.items() + [("method", method), ("url", url)]
-        if k != 'api_key'
-    ]
     data_or_params['api_key'] = settings.API_KEY
     try:
-        with dog_stats_api.timer('comment_client.request.time', tags=tags):
+        with dog_stats_api.timer('comment_client.request.time'):
             if method in ['post', 'put', 'patch']:
                 response = requests.request(method, url, data=data_or_params, timeout=5)
             else:
@@ -55,6 +50,9 @@ def perform_request(method, url, data_or_params=None, *args, **kwargs):
 
     if 200 < response.status_code < 500:
         raise CommentClientError(response.text)
+    # Heroku returns a 503 when an application is in maintenance mode
+    elif response.status_code == 503:
+        raise CommentClientMaintenanceError(response.text)
     elif response.status_code == 500:
         raise CommentClientUnknownError(response.text)
     else:
@@ -72,5 +70,9 @@ class CommentClientError(Exception):
         return repr(self.message)
 
 
+class CommentClientMaintenanceError(CommentClientError):
+    pass
+
+
 class CommentClientUnknownError(CommentClientError):
     pass

lms/static/sass/application.scss → lms/static/sass/application.scss.mako

@@ -36,3 +36,16 @@
 @import 'news';
 
 @import 'shame';
+
+## THEMING
+## -------
+## Set up this file to import an edX theme library if the environment
+## indicates that a theme should be used. The assumption is that the
+## theme resides outside of this main edX repository, in a directory
+## called themes/<theme-name>/, with its base Sass file in
+## themes/<theme-name>/static/sass/_<theme-name>.scss. That one entry
+## point can be used to @import in as many other things as needed.
+% if env.get('THEME_NAME') is not None:
+  // import theme's Sass overrides
+  @import '${env.get('THEME_NAME')}'
+% endif

lms/templates/discussion/maintenance.html

+<%inherit file="../main.html" />
+<h1>We're sorry</h1>
+<p>The forums are currently undergoing maintenance. We'll have them back up shortly!</p>

lms/urls.py

@@ -8,7 +8,7 @@ from . import one_time_startup
 import django.contrib.auth.views
 
 # Uncomment the next two lines to enable the admin:
-if settings.DEBUG:
+if settings.DEBUG or settings.MITX_FEATURES.get('ENABLE_DJANGO_ADMIN_SITE'):
     admin.autodiscover()
 
 urlpatterns = ('',  # nopep8
@@ -330,7 +330,7 @@ if settings.COURSEWARE_ENABLED:
 if settings.ENABLE_JASMINE:
     urlpatterns += (url(r'^_jasmine/', include('django_jasmine.urls')),)
 
-if settings.DEBUG:
+if settings.DEBUG or settings.MITX_FEATURES.get('ENABLE_DJANGO_ADMIN_SITE'):
     ## Jasmine and admin
     urlpatterns += (url(r'^admin/', include(admin.site.urls)),)
 

rakefile

+require 'json'
 require 'rake/clean'
 require './rakefiles/helpers.rb'
 
@@ -7,6 +8,13 @@ end
 
 # Build Constants
 REPO_ROOT = File.dirname(__FILE__)
+ENV_ROOT = File.dirname(REPO_ROOT)
 REPORT_DIR = File.join(REPO_ROOT, "reports")
 
+# Environment constants
+SERVICE_VARIANT = ENV['SERVICE_VARIANT']
+CONFIG_PREFIX = SERVICE_VARIANT ? SERVICE_VARIANT + "." : ""
+ENV_FILE = File.join(ENV_ROOT, CONFIG_PREFIX + "env.json")
+ENV_TOKENS = File.exists?(ENV_FILE) ? JSON.parse(File.read(ENV_FILE)) : {}
+
 task :default => [:test, :pep8, :pylint]

rakefiles/assets.rake

+# Theming constants
+THEME_NAME = ENV_TOKENS['THEME_NAME']
+USE_CUSTOM_THEME = !(THEME_NAME.nil? || THEME_NAME.empty?)
+if USE_CUSTOM_THEME
+    THEME_ROOT = File.join(ENV_ROOT, "themes", THEME_NAME)
+    THEME_SASS = File.join(THEME_ROOT, "static", "sass")
+end
+
+# Run the specified file through the Mako templating engine, providing
+# the ENV_TOKENS to the templating context.
+def preprocess_with_mako(filename)
+    # simple command-line invocation of Mako engine
+    mako = "from mako.template import Template;" +
+           "print Template(filename=\"#{filename}\")" +
+           # Total hack. It works because a Python dict literal has
+           # the same format as a JSON object.
+           ".render(env=#{ENV_TOKENS.to_json});"
+
+    # strip off the .mako extension
+    output_filename = filename.chomp(File.extname(filename))
+
+    # just pipe from stdout into the new file, exiting on failure
+    File.open(output_filename, 'w') do |file|
+      file.write(`python -c '#{mako}'`)
+      exit_code = $?.to_i
+      abort "#{mako} failed with #{exit_code}" if exit_code.to_i != 0
+    end
+end
 
 def xmodule_cmd(watch=false, debug=false)
     xmodule_cmd = 'xmodule_assets common/static/xmodule'
@@ -32,10 +60,17 @@ def coffee_cmd(watch=false, debug=false)
 end
 
 def sass_cmd(watch=false, debug=false)
+    sass_load_paths = ["./common/static/sass"]
+    sass_watch_paths = ["*/static"]
+    if USE_CUSTOM_THEME
+      sass_load_paths << THEME_SASS
+      sass_watch_paths << THEME_SASS
+    end
+
     "sass #{debug ? '--debug-info' : '--style compressed'} " +
-          "--load-path ./common/static/sass " +
+          "--load-path #{sass_load_paths.join(' ')} " +
           "--require ./common/static/sass/bourbon/lib/bourbon.rb " +
-          "#{watch ? '--watch' : '--update'} */static"
+          "#{watch ? '--watch' : '--update'} #{sass_watch_paths.join(' ')}"
 end
 
 desc "Compile all assets"
@@ -46,6 +81,13 @@ namespace :assets do
     desc "Compile all assets in debug mode"
     multitask :debug
 
+    desc "Preprocess all static assets that have the .mako extension"
+    task :preprocess do
+      # Run assets through the Mako templating engine. Right now we
+      # just hardcode the asset filenames.
+      preprocess_with_mako("lms/static/sass/application.scss.mako")
+    end
+
     desc "Watch all assets for changes and automatically recompile"
     task :watch => 'assets:_watch' do
         puts "Press ENTER to terminate".red
@@ -54,9 +96,9 @@ namespace :assets do
 
     {:xmodule => :install_python_prereqs,
      :coffee => :install_node_prereqs,
-     :sass => :install_ruby_prereqs}.each_pair do |asset_type, prereq_task|
+     :sass => [:install_ruby_prereqs, :preprocess]}.each_pair do |asset_type, prereq_tasks|
         desc "Compile all #{asset_type} assets"
-        task asset_type => prereq_task do
+        task asset_type => prereq_tasks do
             cmd = send(asset_type.to_s + "_cmd", watch=false, debug=false)
             if cmd.kind_of?(Array)
                 cmd.each {|c| sh(c)}
@@ -71,7 +113,7 @@ namespace :assets do
 
         namespace asset_type do
             desc "Compile all #{asset_type} assets in debug mode"
-            task :debug => prereq_task do
+            task :debug => prereq_tasks do
                 cmd = send(asset_type.to_s + "_cmd", watch=false, debug=true)
                 sh(cmd)
             end
@@ -82,7 +124,7 @@ namespace :assets do
                 $stdin.gets
             end
 
-            task :_watch => prereq_task do
+            task :_watch => prereq_tasks do
                 cmd = send(asset_type.to_s + "_cmd", watch=true, debug=true)
                 if cmd.kind_of?(Array)
                     cmd.each {|c| background_process(c)}

rakefiles/helpers.rb

@@ -14,16 +14,31 @@ def report_dir_path(dir)
     return File.join(REPORT_DIR, dir.to_s)
 end
 
-def when_changed(unchanged_message, *files)
-    Rake::Task[PREREQS_MD5_DIR].invoke
-    cache_file = File.join(PREREQS_MD5_DIR, files.join('-').gsub(/\W+/, '-')) + '.md5'
+def compute_fingerprint(files, dirs)
     digest = Digest::MD5.new()
+
+    # Digest the contents of all the files.
     Dir[*files].select{|file| File.file?(file)}.each do |file|
         digest.file(file)
     end
-    if !File.exists?(cache_file) or digest.hexdigest != File.read(cache_file)
+
+    # Digest the names of the files in all the dirs.
+    dirs.each do |dir|
+        file_names = Dir.entries(dir).sort.join(" ")
+        digest.update(file_names)
+    end
+
+    digest.hexdigest
+end
+
+# Hash the contents of all the files, and the names of files in the dirs.
+# Run the block if they've changed.
+def when_changed(unchanged_message, files, dirs=[])
+    Rake::Task[PREREQS_MD5_DIR].invoke
+    cache_file = File.join(PREREQS_MD5_DIR, files[0].gsub(/\W+/, '-').sub(/-+$/, '')) + '.md5'
+    if !File.exists?(cache_file) or compute_fingerprint(files, dirs) != File.read(cache_file)
         yield
-        File.write(cache_file, digest.hexdigest)
+        File.write(cache_file, compute_fingerprint(files, dirs))
     elsif !unchanged_message.empty?
         puts unchanged_message
     end

rakefiles/prereqs.rake

 require './rakefiles/helpers.rb'
 
-
 PREREQS_MD5_DIR = ENV["PREREQ_CACHE_DIR"] || File.join(REPO_ROOT, '.prereqs_cache')
 
 CLOBBER.include(PREREQS_MD5_DIR)
@@ -13,7 +12,7 @@ task :install_prereqs => [:install_node_prereqs, :install_ruby_prereqs, :install
 desc "Install all node prerequisites for the lms and cms"
 task :install_node_prereqs => "ws:migrate" do
     unchanged = 'Node requirements unchanged, nothing to install'
-    when_changed(unchanged, 'package.json') do
+    when_changed(unchanged, ['package.json']) do
         sh('npm install')
     end unless ENV['NO_PREREQ_INSTALL']
 end
@@ -21,20 +20,21 @@ end
 desc "Install all ruby prerequisites for the lms and cms"
 task :install_ruby_prereqs => "ws:migrate" do
     unchanged = 'Ruby requirements unchanged, nothing to install'
-    when_changed(unchanged, 'Gemfile') do
+    when_changed(unchanged, ['Gemfile']) do
         sh('bundle install')
     end unless ENV['NO_PREREQ_INSTALL']
 end
 
 desc "Install all python prerequisites for the lms and cms"
 task :install_python_prereqs => "ws:migrate" do
+    site_packages_dir = `python -c 'import os; import distutils.sysconfig as dusc; print dusc.get_python_lib()'`.chomp
     unchanged = 'Python requirements unchanged, nothing to install'
-    when_changed(unchanged, 'requirements/**/*') do
+    when_changed(unchanged, ['requirements/**/*'], [site_packages_dir]) do
         ENV['PIP_DOWNLOAD_CACHE'] ||= '.pip_download_cache'
         sh('pip install --exists-action w -r requirements/edx/base.txt')
         sh('pip install --exists-action w -r requirements/edx/post.txt')
-        # Check for private-requirements.txt: used to install our libs as working dirs,
-        # or personal-use tools.
+        # requirements/private.txt is used to install our libs as
+        # working dirs, or for personal-use tools.
         if File.file?("requirements/private.txt")
             sh('pip install -r requirements/private.txt')
         end

rakefiles/quality.rake

+def run_pylint(system, report_dir, flags='')
+    apps = Dir["#{system}", "#{system}/djangoapps/*", "#{system}/lib/*"].map do |app|
+        File.basename(app)
+    end.select do |app|
+        app !=~ /.pyc$/
+    end.map do |app|
+        if app =~ /.py$/
+            app.gsub('.py', '')
+        else
+            app
+        end
+    end
+
+    pythonpath_prefix = "PYTHONPATH=#{system}:#{system}/djangoapps:#{system}/lib:common/djangoapps:common/lib"
+    sh("#{pythonpath_prefix} pylint #{flags} -f parseable #{apps.join(' ')} | tee #{report_dir}/pylint.report")
+end
+
 
 [:lms, :cms, :common].each do |system|
     report_dir = report_dir_path(system)
@@ -11,21 +28,18 @@
 
     desc "Run pylint on all #{system} code"
     task "pylint_#{system}" => [report_dir, :install_python_prereqs] do
-        apps = Dir["#{system}/*.py", "#{system}/djangoapps/*", "#{system}/lib/*"].map do |app|
-            File.basename(app)
-        end.select do |app|
-            app !=~ /.pyc$/
-        end.map do |app|
-            if app =~ /.py$/
-                app.gsub('.py', '')
-            else
-                app
-            end
+        run_pylint(system, report_dir)
+    end
+    namespace "pylint_#{system}" do
+        desc "Run pylint checking for errors only, and aborting if there are any"
+        task :errors do
+            run_pylint(system, report_dir, '-E')
         end
-
-        pythonpath_prefix = "PYTHONPATH=#{system}:#{system}/djangoapps:#{system}/lib:common/djangoapps:common/lib"
-        sh("#{pythonpath_prefix} pylint --rcfile=.pylintrc -f parseable #{apps.join(' ')} | tee #{report_dir}/pylint.report")
     end
+    namespace :pylint do
+        task :errors => "pylint_#{system}:errors"
+    end
+
     task :pylint => "pylint_#{system}"
 
 end
\ No newline at end of file

requirements/edx-sandbox/local.txt

+# Install these packages from the edx-platform working tree
+# NOTE: if you change code in these packages, you MUST change the version
+# number in its setup.py or the code WILL NOT be installed during deploy.
+common/lib/calc
+common/lib/chem
+common/lib/sandbox-packages

requirements/edx-sandbox/post.txt

 # Packages to install in the Python sandbox for secured execution.
 scipy==0.11.0
 lxml==3.0.1
--e common/lib/calc
--e common/lib/chem
--e common/lib/sandbox-packages

requirements/edx/base.txt

@@ -74,6 +74,7 @@ lettuce==0.2.16
 mock==0.8.0
 nosexcover==1.0.7
 pep8==1.4.5
+pylint==0.28
 rednose==0.3
 selenium==2.31.0
 splinter==0.5.0
@@ -81,7 +82,3 @@ django_nose==1.1
 django-jasmine==0.3.2
 django_debug_toolbar
 django-debug-toolbar-mongo
-
-# Install pylint from a specific commit on trunk
-# to get the fix for this issue: http://www.logilab.org/ticket/122793
-https://bitbucket.org/logilab/pylint/get/e828cb5.zip

requirements/edx/github.txt

@@ -8,5 +8,5 @@
 -e git://github.com/eventbrite/zendesk.git@d53fe0e81b623f084e91776bcf6369f8b7b63879#egg=zendesk
 
 # Our libraries:
--e git+https://github.com/edx/XBlock.git@483e0cb1#egg=XBlock
+-e git+https://github.com/edx/XBlock.git@2144a25d#egg=XBlock
 -e git+https://github.com/edx/codejail.git@07494f1#egg=codejail