# pylint: disable=W0223
"""VideoAlpha is ungraded Xmodule for support video content.
It's new improved video module, which support additional feature:
- Can play non-YouTube video sources via in-browser HTML5 video player.
- YouTube defaults to HTML5 mode from the start.
- Speed changes in both YouTube and non-YouTube videos happen via
in-browser HTML5 video method (when in HTML5 mode).
- Navigational subtitles can be disabled altogether via an attribute
in XML.
"""
import json
import logging
from lxml import etree
from pkg_resources import resource_string, resource_listdir
from django.http import Http404
from django.conf import settings
from xmodule.x_module import XModule
from xmodule.editing_module import TabsEditingDescriptor
from xmodule.raw_module import RawDescriptor
from xmodule.modulestore.mongo import MongoModuleStore
from xmodule.modulestore.django import modulestore
from xmodule.contentstore.content import StaticContent
from xblock.core import Integer, Scope, String
import datetime
import time
import textwrap
log = logging.getLogger(__name__)
class VideoAlphaFields(object):
"""Fields for `VideoAlphaModule` and `VideoAlphaDescriptor`."""
data = String(help="XML data for the problem",
default=textwrap.dedent('''\
'''),
scope=Scope.content)
position = Integer(help="Current position in the video", scope=Scope.user_state, default=0)
display_name = String(
display_name="Display Name", help="Display name for this module",
default="Video Alpha",
scope=Scope.settings
)
class VideoAlphaModule(VideoAlphaFields, XModule):
"""
XML source example:
"""
video_time = 0
icon_class = 'video'
js = {
'js': [
resource_string(__name__, 'js/src/videoalpha/01_initialize.js'),
resource_string(__name__, 'js/src/videoalpha/02_html5_video.js'),
resource_string(__name__, 'js/src/videoalpha/03_video_player.js'),
resource_string(__name__, 'js/src/videoalpha/04_video_control.js'),
resource_string(__name__, 'js/src/videoalpha/05_video_quality_control.js'),
resource_string(__name__, 'js/src/videoalpha/06_video_progress_slider.js'),
resource_string(__name__, 'js/src/videoalpha/07_video_volume_control.js'),
resource_string(__name__, 'js/src/videoalpha/08_video_speed_control.js'),
resource_string(__name__, 'js/src/videoalpha/09_video_caption.js'),
resource_string(__name__, 'js/src/videoalpha/10_main.js')
]
}
css = {'scss': [resource_string(__name__, 'css/videoalpha/display.scss')]}
js_module_name = "VideoAlpha"
def __init__(self, *args, **kwargs):
XModule.__init__(self, *args, **kwargs)
xmltree = etree.fromstring(self.data)
# Front-end expects an empty string, or a properly formatted string with YouTube IDs.
self.youtube_streams = xmltree.get('youtube', '')
self.sub = xmltree.get('sub')
self.autoplay = xmltree.get('autoplay') or ''
if self.autoplay.lower() not in ['true', 'false']:
self.autoplay = 'true'
self.position = 0
self.show_captions = xmltree.get('show_captions', 'true')
self.sources = {
'main': self._get_source(xmltree),
'mp4': self._get_source(xmltree, ['mp4']),
'webm': self._get_source(xmltree, ['webm']),
'ogv': self._get_source(xmltree, ['ogv']),
}
self.track = self._get_track(xmltree)
self.start_time, self.end_time = self.get_timeframe(xmltree)
def _get_source(self, xmltree, exts=None):
"""Find the first valid source, which ends with one of `exts`."""
exts = ['mp4', 'ogv', 'avi', 'webm'] if exts is None else exts
condition = lambda src: any([src.endswith(ext) for ext in exts])
return self._get_first_external(xmltree, 'source', condition)
def _get_track(self, xmltree):
"""Find the first valid track."""
return self._get_first_external(xmltree, 'track')
def _get_first_external(self, xmltree, tag, condition=bool):
"""Will return the first 'valid' element of the given tag.
'valid' means that `condition('src' attribute) == True`
"""
result = None
for element in xmltree.findall(tag):
src = element.get('src')
if condition(src):
result = src
break
return result
def get_timeframe(self, xmltree):
""" Converts 'start_time' and 'end_time' parameters in video tag to seconds.
If there are no parameters, returns empty string. """
def parse_time(str_time):
"""Converts s in '12:34:45' format to seconds. If s is
None, returns empty string"""
if str_time is None:
return ''
else:
obj_time = time.strptime(str_time, '%H:%M:%S')
return datetime.timedelta(
hours=obj_time.tm_hour,
minutes=obj_time.tm_min,
seconds=obj_time.tm_sec
).total_seconds()
return parse_time(xmltree.get('start_time')), parse_time(xmltree.get('end_time'))
def handle_ajax(self, dispatch, data):
"""This is not being called right now and we raise 404 error."""
log.debug(u"GET {0}".format(data))
log.debug(u"DISPATCH {0}".format(dispatch))
raise Http404()
def get_instance_state(self):
"""Return information about state (position)."""
return json.dumps({'position': self.position})
def get_html(self):
if isinstance(modulestore(), MongoModuleStore):
caption_asset_path = StaticContent.get_base_url_path_for_course_assets(self.location) + '/subs_'
else:
# VS[compat]
# cdodge: filesystem static content support.
caption_asset_path = "/static/subs/"
return self.system.render_template('videoalpha.html', {
'youtube_streams': self.youtube_streams,
'id': self.location.html_id(),
'sub': self.sub,
'autoplay': self.autoplay,
'sources': self.sources,
'track': self.track,
'display_name': self.display_name_with_default,
# This won't work when we move to data that
# isn't on the filesystem
'data_dir': getattr(self, 'data_dir', None),
'caption_asset_path': caption_asset_path,
'show_captions': self.show_captions,
'start': self.start_time,
'end': self.end_time,
'autoplay': settings.MITX_FEATURES.get('AUTOPLAY_VIDEOS', True)
})
class VideoAlphaDescriptor(VideoAlphaFields, TabsEditingDescriptor, RawDescriptor):
"""Descriptor for `VideoAlphaModule`."""
module_class = VideoAlphaModule
tabs = [
{
'name': "XML",
'template': "videoalpha/codemirror-edit.html",
'css': {'scss': [resource_string(__name__, 'css/tabs/codemirror.scss')]},
'current': True,
},
# {
# 'name': "Subtitles",
# 'template': "videoalpha/subtitles.html",
# },
{
'name': "Settings",
'template': "tabs/metadata-edit-tab.html"
}
]