def _get_video(edx_video_id):
"""
Get a Video instance, prefetching encoded video and course information.
Raises ValVideoNotFoundError if the video cannot be retrieved.
"""
try:
return Video.objects.prefetch_related(
"encoded_videos", "courses").get(edx_video_id=edx_video_id)
except Video.DoesNotExist:
error_message = u"Video not found for edx_video_id: {0}".format(
edx_video_id)
raise ValVideoNotFoundError(error_message)
except Exception:
error_message = u"Could not get edx_video_id: {0}".format(edx_video_id)
logger.exception(error_message)
raise ValInternalError(error_message)
def _get_video(edx_video_id):
"""
Get a Video instance, prefetching encoded video and course information.
Raises ValVideoNotFoundError if the video cannot be retrieved.
"""
try:
encoded_videos = EncodedVideo.objects.select_related("profile")
return Video.objects \
.prefetch_related(Prefetch("encoded_videos", queryset=encoded_videos)) \
.prefetch_related("courses") \
.get(edx_video_id=edx_video_id)
except Video.DoesNotExist as no_video_error:
error_message = f"Video not found for edx_video_id: {edx_video_id}"
raise ValVideoNotFoundError(error_message) from no_video_error
except Exception as exc:
error_message = f"Could not get edx_video_id: {edx_video_id}"
logger.exception(error_message)
raise ValInternalError(error_message) from exc
def get_video_info_for_course_and_profiles(course_id, profiles):
"""
Returns a dict of edx_video_ids with a dict of requested profiles.
Args:
course_id (str): id of the course
profiles (list): list of profile_names
Returns:
(dict): Returns all the profiles attached to a specific
edx_video_id
{
edx_video_id: {
'duration': length of the video in seconds,
'profiles': {
profile_name: {
'url': url of the encoding
'file_size': size of the file in bytes
},
}
},
}
Example:
Given two videos with two profiles each in course_id 'test_course':
{
u'edx_video_id_1': {
u'duration: 1111,
u'profiles': {
u'mobile': {
'url': u'http: //www.example.com/meow',
'file_size': 2222
},
u'desktop': {
'url': u'http: //www.example.com/woof',
'file_size': 4444
}
}
},
u'edx_video_id_2': {
u'duration: 2222,
u'profiles': {
u'mobile': {
'url': u'http: //www.example.com/roar',
'file_size': 6666
},
u'desktop': {
'url': u'http: //www.example.com/bzzz',
'file_size': 8888
}
}
}
}
"""
# In case someone passes in a key (VAL doesn't really understand opaque keys)
course_id = unicode(course_id)
try:
encoded_videos = EncodedVideo.objects.filter(
profile__profile_name__in=profiles,
video__courses__course_id=course_id).select_related()
except Exception:
error_message = u"Could not get encoded videos for course: {0}".format(
course_id)
logger.exception(error_message)
raise ValInternalError(error_message)
# DRF serializers were causing extra queries for some reason...
return_dict = {}
for enc_vid in encoded_videos:
# Add duration to edx_video_id
return_dict.setdefault(enc_vid.video.edx_video_id, {}).update({
"duration":
enc_vid.video.duration,
})
# Add profile information to edx_video_id's profiles
return_dict[enc_vid.video.edx_video_id].setdefault(
"profiles", {}).update({
enc_vid.profile.profile_name: {
"url": enc_vid.url,
"file_size": enc_vid.file_size,
}
})
return return_dict