Added extra field to CCX model for Course Models

REST APIs modified

lms/djangoapps/ccx/api/v0/serializers.py

@@ -17,6 +17,7 @@ class CCXCourseSerializer(serializers.ModelSerializer):
     start = serializers.CharField(allow_blank=True)
     due = serializers.CharField(allow_blank=True)
     max_students_allowed = serializers.IntegerField(source='max_student_enrollments_allowed')
+    course_modules = serializers.SerializerMethodField()
 
     class Meta(object):
         model = CustomCourseForEdX
@@ -28,6 +29,7 @@ class CCXCourseSerializer(serializers.ModelSerializer):
             "start",
             "due",
             "max_students_allowed",
+            "course_modules",
         )
         read_only_fields = (
             "ccx_course_id",
@@ -42,3 +44,10 @@ class CCXCourseSerializer(serializers.ModelSerializer):
         Getter for the CCX Course ID
         """
         return unicode(CCXLocator.from_course_locator(obj.course.id, obj.id))
+
+    @staticmethod
+    def get_course_modules(obj):
+        """
+        Getter for the Course Modules. The list is stored in a compressed field.
+        """
+        return obj.structure or []

lms/djangoapps/ccx/migrations/0002_customcourseforedx_structure_json.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ccx', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='customcourseforedx',
+            name='structure_json',
+            field=models.TextField(null=True, verbose_name=b'Structure JSON', blank=True),
+        ),
+    ]

lms/djangoapps/ccx/models.py

 """
 Models for the custom course feature
 """
-from datetime import datetime
+import json
 import logging
+from datetime import datetime
 
 from django.contrib.auth.models import User
 from django.db import models
@@ -24,6 +25,9 @@ class CustomCourseForEdX(models.Model):
     course_id = CourseKeyField(max_length=255, db_index=True)
     display_name = models.CharField(max_length=255)
     coach = models.ForeignKey(User, db_index=True)
+    # if not empty, this field contains a json serialized list of
+    # the master course modules
+    structure_json = models.TextField(verbose_name='Structure JSON', blank=True, null=True)
 
     class Meta(object):
         app_label = 'ccx'
@@ -107,6 +111,15 @@ class CustomCourseForEdX(models.Model):
             value += u' UTC'
         return value
 
+    @property
+    def structure(self):
+        """
+        Deserializes a course structure JSON object
+        """
+        if self.structure_json:
+            return json.loads(self.structure_json)
+        return None
+
 
 class CcxFieldOverride(models.Model):
     """

lms/djangoapps/ccx/tests/test_models.py

 """
 tests for the models
 """
+import json
 from datetime import datetime, timedelta
 from django.utils.timezone import UTC
 from mock import patch
@@ -30,11 +31,11 @@ class TestCCX(ModuleStoreTestCase):
     def setUp(self):
         """common setup for all tests"""
         super(TestCCX, self).setUp()
-        self.course = course = CourseFactory.create()
-        coach = AdminFactory.create()
-        role = CourseCcxCoachRole(course.id)
-        role.add_users(coach)
-        self.ccx = CcxFactory(course_id=course.id, coach=coach)
+        self.course = CourseFactory.create()
+        self.coach = AdminFactory.create()
+        role = CourseCcxCoachRole(self.course.id)
+        role.add_users(self.coach)
+        self.ccx = CcxFactory(course_id=self.course.id, coach=self.coach)
 
     def set_ccx_override(self, field, value):
         """Create a field override for the test CCX on <field> with <value>"""
@@ -209,3 +210,28 @@ class TestCCX(ModuleStoreTestCase):
         self.set_ccx_override('max_student_enrollments_allowed', expected)
         actual = self.ccx.max_student_enrollments_allowed  # pylint: disable=no-member
         self.assertEqual(expected, actual)
+
+    def test_structure_json_default_empty(self):
+        """
+        By default structure_json does not contain anything
+        """
+        self.assertEqual(self.ccx.structure_json, None)  # pylint: disable=no-member
+        self.assertEqual(self.ccx.structure, None)  # pylint: disable=no-member
+
+    def test_structure_json(self):
+        """
+        Test a json stored in the structure_json
+        """
+        dummy_struct = [
+            "block-v1:Organization+CN101+CR-FALL15+type@chapter+block@Unit_4",
+            "block-v1:Organization+CN101+CR-FALL15+type@chapter+block@Unit_5",
+            "block-v1:Organization+CN101+CR-FALL15+type@chapter+block@Unit_11"
+        ]
+        json_struct = json.dumps(dummy_struct)
+        ccx = CcxFactory(
+            course_id=self.course.id,
+            coach=self.coach,
+            structure_json=json_struct
+        )
+        self.assertEqual(ccx.structure_json, json_struct)  # pylint: disable=no-member
+        self.assertEqual(ccx.structure, dummy_struct)  # pylint: disable=no-member

lms/djangoapps/ccx/tests/test_utils.py

 """
 test utils
 """
+import mock
 from nose.plugins.attrib import attr
 
-from lms.djangoapps.ccx.tests.factories import CcxFactory
 from student.roles import CourseCcxCoachRole
 from student.tests.factories import (
     AdminFactory,
@@ -12,7 +12,11 @@ from xmodule.modulestore.tests.django_utils import (
     ModuleStoreTestCase,
     TEST_DATA_SPLIT_MODULESTORE)
 from xmodule.modulestore.tests.factories import CourseFactory
+from opaque_keys.edx.keys import CourseKey
 
+from lms.djangoapps.ccx import utils
+from lms.djangoapps.ccx.tests.factories import CcxFactory
+from lms.djangoapps.ccx.tests.utils import CcxTestCase
 from ccx_keys.locator import CCXLocator
 
 
@@ -47,3 +51,45 @@ class TestGetCCXFromCCXLocator(ModuleStoreTestCase):
         course_key = CCXLocator.from_course_locator(self.course.id, ccx.id)
         result = self.call_fut(course_key)
         self.assertEqual(result, ccx)
+
+
+@attr('shard_1')
+class TestGetCourseChapters(CcxTestCase):
+    """
+    Tests for the `get_course_chapters` util function
+    """
+    def setUp(self):
+        """
+        Set up tests
+        """
+        super(TestGetCourseChapters, self).setUp()
+        self.course_key = self.course.location.course_key
+
+    def test_get_structure_non_existing_key(self):
+        """
+        Test to get the course structure
+        """
+        self.assertEqual(utils.get_course_chapters(None), None)
+        # build a fake key
+        fake_course_key = CourseKey.from_string('course-v1:FakeOrg+CN1+CR-FALLNEVER1')
+        self.assertEqual(utils.get_course_chapters(fake_course_key), None)
+
+    @mock.patch('openedx.core.djangoapps.content.course_structures.models.CourseStructure.structure',
+                new_callable=mock.PropertyMock)
+    def test_wrong_course_structure(self, mocked_attr):
+        """
+        Test the case where the course  has an unexpected structure.
+        """
+        mocked_attr.return_value = {'foo': 'bar'}
+        self.assertEqual(utils.get_course_chapters(self.course_key), [])
+
+    def test_get_chapters(self):
+        """
+        Happy path
+        """
+        course_chapters = utils.get_course_chapters(self.course_key)
+        self.assertEqual(len(course_chapters), 2)
+        self.assertEqual(
+            sorted(course_chapters),
+            sorted([unicode(child) for child in self.course.children])
+        )

lms/djangoapps/ccx/utils.py

@@ -23,6 +23,7 @@ from instructor.enrollment import (
 from instructor.access import allow_access
 from instructor.views.tools import get_student_from_identifier
 from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
+from openedx.core.djangoapps.content.course_structures.models import CourseStructure
 from student.models import CourseEnrollment
 from student.roles import CourseCcxCoachRole
 
@@ -284,3 +285,29 @@ def is_email(identifier):
     except ValidationError:
         return False
     return True
+
+
+def get_course_chapters(course_key):
+    """
+    Extracts the chapters from a course structure.
+    If the course does not exist returns None.
+    If the structure does not contain 1st level children,
+    it returns an empty list.
+
+    Args:
+        course_key (CourseLocator): the course key
+    Returns:
+        list (string): a list of string representing the chapters modules
+            of the course
+    """
+    if course_key is None:
+        return
+    try:
+        course_obj = CourseStructure.objects.get(course_id=course_key)
+    except CourseStructure.DoesNotExist:
+        return
+    course_struct = course_obj.structure
+    try:
+        return course_struct['blocks'][course_struct['root']].get('children', [])
+    except KeyError:
+        return []