Merge pull request #73 from edx/ammar/add-video-image-urls-field

add support in model for multiple video image urls

.travis.yml

@@ -10,6 +10,5 @@ script:
 branches:
     only:
       - master
-      - ammar/course-rerun-import-export
 after_success:
   coveralls

edxval/migrations/0005_videoimage.py

@@ -21,6 +21,7 @@ class Migration(migrations.Migration):
                 ('created', model_utils.fields.AutoCreatedField(default=django.utils.timezone.now, verbose_name='created', editable=False)),
                 ('modified', model_utils.fields.AutoLastModifiedField(default=django.utils.timezone.now, verbose_name='modified', editable=False)),
                 ('image', edxval.models.CustomizableImageField(null=True, blank=True)),
+                ('generated_images', edxval.models.ListField()),
                 ('course_video', models.OneToOneField(related_name='video_image', to='edxval.CourseVideo')),
             ],
             options={

edxval/models.py

@@ -12,12 +12,14 @@
 """
 
 from contextlib import closing
+import json
 import logging
 import os
 from uuid import uuid4
 
 from django.db import models
 from django.dispatch import receiver
+from django.core.exceptions import ValidationError
 from django.core.validators import MinValueValidator, RegexValidator
 from django.core.urlresolvers import reverse
 
@@ -28,6 +30,7 @@
 logger = logging.getLogger(__name__)  # pylint: disable=C0103
 
 URL_REGEX = r'^[a-zA-Z0-9\-_]*$'
+LIST_MAX_ITEMS = 3
 
 
 class ModelFactoryWithValidation(object):
@@ -199,12 +202,70 @@ def deconstruct(self):
         return name, path, args, kwargs
 
 
+class ListField(models.TextField):
+    """
+    ListField use to store and retrieve list data.
+    """
+    __metaclass__ = models.SubfieldBase
+
+    def get_prep_value(self, value):
+        """
+        Converts a list to its json represetation to store in database as text.
+        """
+        return json.dumps(value)
+
+    def to_python(self, value):
+        """
+        Converts the value into a list.
+        """
+        if not value:
+            value = []
+
+        # If a list is set then validated its items
+        if isinstance(value, list):
+            return self.validate(value)
+        else:  # try to de-serialize value and expect list and then validate
+            try:
+                py_list = json.loads(value)
+
+                if not isinstance(py_list, list):
+                    raise TypeError
+
+                self.validate(py_list)
+            except (ValueError, TypeError):
+                raise ValidationError(u'Must be a valid list of strings.')
+
+        return py_list
+
+    def validate(self, value):
+        """
+        Validate data before saving to database.
+
+        Arguemtns:
+            value(list): list to be validated
+
+        Returns:
+            list if validation is successful
+
+        Raises:
+            ValidationError
+        """
+        if len(value) > LIST_MAX_ITEMS:
+            raise ValidationError(u'list must not contain more than {} items.'.format(LIST_MAX_ITEMS))
+
+        if all(isinstance(item, str) for item in value) is False:
+            raise ValidationError(u'list must only contain strings.')
+
+        return value
+
+
 class VideoImage(TimeStampedModel):
     """
     Image model for course video.
     """
     course_video = models.OneToOneField(CourseVideo, related_name="video_image")
     image = CustomizableImageField()
+    generated_images = ListField()
 
     @classmethod
     def create_or_update(cls, course_video, file_name, image_data=None):

edxval/tests/test_api.py

@@ -7,14 +7,15 @@
 from mock import patch
 from lxml import etree
 
+from django.core.exceptions import ValidationError
 from django.core.files.images import ImageFile
 from django.test import TestCase
 from django.db import DatabaseError
 from django.core.urlresolvers import reverse
 from rest_framework import status
 from ddt import ddt, data, unpack
 
-from edxval.models import Profile, Video, EncodedVideo, CourseVideo, VideoImage
+from edxval.models import Profile, Video, EncodedVideo, CourseVideo, VideoImage, LIST_MAX_ITEMS
 from edxval import api as api
 from edxval.api import (
     SortDirection,
@@ -1335,3 +1336,53 @@ def test_update_video_image_exception(self):
                 does_not_course_id
             )
         )
+
+    def test_video_image_urls_field(self):
+        """
+        Test `VideoImage.generated_images` field works as expected.
+        """
+        image_urls = ['video-images/a.png', 'video-images/b.png']
+
+        # an empty list should be returned when there is no value for urls
+        self.assertEqual(self.course_video.video_image.generated_images, [])
+
+        # set a list with data and expect the same list to be returned
+        course_video = CourseVideo.objects.create(video=self.video, course_id='course101')
+        video_image = VideoImage.objects.create(course_video=course_video)
+        video_image.generated_images = image_urls
+        video_image.save()
+        self.assertEqual(video_image.generated_images, image_urls)
+        self.assertEqual(course_video.video_image.generated_images, image_urls)
+
+    def test_video_image_urls_field_validation(self):
+        """
+        Test `VideoImage.generated_images` field validation.
+        """
+        course_video = CourseVideo.objects.create(video=self.video, course_id='course101')
+        video_image = VideoImage.objects.create(course_video=course_video)
+
+        # expect a validation error if we try to set a list with more than 3 items
+        with self.assertRaises(ValidationError) as set_exception:
+            video_image.generated_images = ['a', 'b', 'c', 'd']
+
+        self.assertEqual(
+            set_exception.exception.message,
+            u'list must not contain more than {} items.'.format(LIST_MAX_ITEMS)
+        )
+
+        # expect a validation error if we try to a list with non-string items
+        with self.assertRaises(ValidationError) as set_exception:
+            video_image.generated_images = ['a', 1, 2]
+
+        self.assertEqual(set_exception.exception.message, u'list must only contain strings.')
+
+        # expect a validation error if we try to set non list data
+        exception_messages = set()
+        for item in ('a string', 555, {'a': 1}, (1,), video_image):
+            with self.assertRaises(ValidationError) as set_exception:
+                video_image.generated_images = item
+
+            exception_messages.add(set_exception.exception.message)
+
+        self.assertEqual(len(exception_messages), 1)
+        self.assertEqual(exception_messages.pop(), u'Must be a valid list of strings.')

setup.py

@@ -39,7 +39,7 @@ def load_requirements(*requirements_paths):
 
 setup(
     name='edxval',
-    version='0.0.15',
+    version='0.0.14',
     author='edX',
     url='http://github.com/edx/edx-val',
     description='edx-val',