Added subtitle model and API

edxval/admin.py

@@ -3,9 +3,9 @@ Admin file for django app edxval.
 """
 
 from django.contrib import admin
-from .models import Video, Profile, EncodedVideo
+from .models import Video, Profile, EncodedVideo, Subtitle
 
 admin.site.register(Video)
 admin.site.register(Profile)
 admin.site.register(EncodedVideo)
-
+admin.site.register(Subtitle)

edxval/api.py

@@ -139,6 +139,11 @@ def get_video_info(edx_video_id, location=None):  # pylint: disable=W0613
                         extension: 3 letter extension of video
                         width: horizontal pixel resolution
                         height: vertical pixel resolution
+                subtitles: a list of Subtitle dicts
+                    fmt: file format (SRT or SJSON)
+                    language: language code
+                    content_url: url of file
+                    url: api url to subtitle
             }
 
     Raises:

edxval/models.py

@@ -29,6 +29,7 @@ invalid profile_name will be returned.
 
 from django.db import models
 from django.core.validators import MinValueValidator, RegexValidator
+from django.core.urlresolvers import reverse
 
 
 url_regex = r'^[a-zA-Z0-9\-]*$'
@@ -78,6 +79,9 @@ class Video(models.Model):
     client_video_id = models.CharField(max_length=255, db_index=True)
     duration = models.FloatField(validators=[MinValueValidator(0)])
 
+    def __str__(self):
+        return self.edx_video_id
+
 
 class CourseVideos(models.Model):
     """
@@ -89,7 +93,7 @@ class CourseVideos(models.Model):
     course_id = models.CharField(max_length=255)
     video = models.ForeignKey(Video)
 
-    class Meta:
+    class Meta:  # pylint: disable=C1001
         """
         course_id is listed first in this composite index
         """
@@ -108,3 +112,34 @@ class EncodedVideo(models.Model):
 
     profile = models.ForeignKey(Profile, related_name="+")
     video = models.ForeignKey(Video, related_name="encoded_videos")
+
+
+SUBTITLE_FORMATS = (
+    ('srt', 'SubRip'),
+    ('sjson', 'SRT JSON')
+)
+
+
+class Subtitle(models.Model):
+    """
+    Subtitle for video
+    """
+    created = models.DateTimeField(auto_now_add=True)
+    modified = models.DateTimeField(auto_now=True)
+    video = models.ForeignKey(Video, related_name="subtitles")
+    fmt = models.CharField(max_length=20, db_index=True, choices=SUBTITLE_FORMATS)
+    language = models.CharField(max_length=8, db_index=True)
+    content = models.TextField()
+
+    def __str__(self):
+        return '%s Subtitle for %s' % (self.language, self.video)
+
+    def get_absolute_url(self):
+        return reverse('subtitle-content', args=[str(self.id)])
+
+    @property
+    def content_type(self):
+        if self.fmt == 'sjson':
+            return 'application/json'
+        else:
+            return 'text/plain'

edxval/serializers.py

@@ -7,7 +7,7 @@ EncodedVideoSerializer which uses the profile_name as it's profile field.
 from rest_framework import serializers
 from django.core.exceptions import ValidationError
 
-from edxval.models import Profile, Video, EncodedVideo
+from edxval.models import Profile, Video, EncodedVideo, Subtitle
 
 
 class ProfileSerializer(serializers.ModelSerializer):
@@ -51,6 +51,41 @@ class EncodedVideoSerializer(serializers.ModelSerializer):
         return data.get('profile', None)
 
 
+class SubtitleSerializer(serializers.HyperlinkedModelSerializer):
+    """
+    Serializer for Subtitle objects
+    """
+    content_url = serializers.CharField(source='get_absolute_url', read_only=True)
+    content = serializers.CharField(write_only=True)
+
+    def validate_content(self, attrs, source):
+        """
+        Validate that the subtitle is in the correct format
+        """
+        value = attrs[source]
+        if attrs.get('fmt') == 'sjson':
+            import json
+            try:
+                loaded = json.loads(value)
+            except ValueError:
+                raise serializers.ValidationError("Not in JSON format")
+            else:
+                attrs[source] = json.dumps(loaded)
+        return attrs
+
+    class Meta:  # pylint: disable=C1001, C0111
+        model = Subtitle
+        lookup_field = "id"
+        fields = (
+            "fmt",
+            "language",
+            "id",
+            "content_url",
+            "url",
+            "content"
+        )
+
+
 class VideoSerializer(serializers.HyperlinkedModelSerializer):
     """
     Serializer for Video object
@@ -58,6 +93,7 @@ class VideoSerializer(serializers.HyperlinkedModelSerializer):
     encoded_videos takes a list of dicts EncodedVideo data.
     """
     encoded_videos = EncodedVideoSerializer(many=True, allow_add_remove=True)
+    subtitles = SubtitleSerializer(many=True, allow_add_remove=True)
 
     class Meta:  # pylint: disable=C0111
         model = Video

edxval/urls.py

@@ -18,4 +18,13 @@ urlpatterns = patterns(
         views.VideoDetail.as_view(),
         name="video-detail"
     ),
+    url(
+    	r'^edxval/subtitle/(?P<id>[\d]+)$',
+        views.SubtitleDetail.as_view(),
+        name="subtitle-detail"
+    ),
+    url(r'^edxval/subtitle/(?P<subtitle_id>[\d]+)/content$',
+        views.get_subtitle,
+        name="subtitle-content"
+    ),
 )

edxval/views.py

@@ -3,11 +3,14 @@ Views file for django app edxval.
 """
 
 from rest_framework import generics
+from django.http import HttpResponse
+from django.views.decorators.http import last_modified
 
-from edxval.models import Video, Profile
+from edxval.models import Video, Profile, Subtitle
 from edxval.serializers import (
     VideoSerializer,
-    ProfileSerializer
+    ProfileSerializer,
+    SubtitleSerializer
 )
 
 
@@ -36,3 +39,22 @@ class VideoDetail(generics.RetrieveUpdateDestroyAPIView):
     lookup_field = "edx_video_id"
     queryset = Video.objects.all()
     serializer_class = VideoSerializer
+
+
+class SubtitleDetail(generics.RetrieveUpdateDestroyAPIView):
+    """
+    Gets a subtitle instance given its id
+    """
+    lookup_field = "id"
+    queryset = Subtitle.objects.all()
+    serializer_class = SubtitleSerializer
+
+
+@last_modified(last_modified_func=lambda request, subtitle_id: Subtitle.objects.get(pk=subtitle_id).modified)
+def get_subtitle(request, subtitle_id):
+    """
+    Return content of subtitle by id
+    """
+    sub = Subtitle.objects.get(pk=subtitle_id)
+    response = HttpResponse(sub.content, content_type=sub.content_type)
+    return response