#49 [niconico] Improved extraction and support encrypted/SMILE movies

Co-authored-by: tsukumijima <tsukumijima@users.noreply.github.com>
Co-authored-by: tsukumi <39271166+tsukumijima@users.noreply.github.com>
Co-authored-by: Bepis <36346617+bbepis@users.noreply.github.com>
Co-authored-by: pukkandan <pukkandan@gmail.com>

youtube_dlc/YoutubeDL.py

@@ -2681,7 +2681,7 @@ class YoutubeDL(object):
                     '|',
                     format_field(f, 'filesize', ' %s', func=format_bytes) + format_field(f, 'filesize_approx', '~%s', func=format_bytes),
                     format_field(f, 'tbr', '%4dk'),
-                    f.get('protocol').replace('http_dash_segments', 'dash').replace("native", "n"),
+                    f.get('protocol').replace('http_dash_segments', 'dash').replace("native", "n").replace('niconico_', ''),
                     '|',
                     format_field(f, 'vcodec', default='unknown').replace('none', ''),
                     format_field(f, 'vbr', '%4dk'),

youtube_dlc/downloader/__init__.py

@@ -21,6 +21,7 @@ from .http import HttpFD
 from .rtmp import RtmpFD
 from .rtsp import RtspFD
 from .ism import IsmFD
+from .niconico import NiconicoDmcFD
 from .youtube_live_chat import YoutubeLiveChatReplayFD
 from .external import (
     get_external_downloader,
@@ -36,6 +37,7 @@ PROTOCOL_MAP = {
     'f4m': F4mFD,
     'http_dash_segments': DashSegmentsFD,
     'ism': IsmFD,
+    'niconico_dmc': NiconicoDmcFD,
     'youtube_live_chat_replay': YoutubeLiveChatReplayFD,
 }
 

youtube_dlc/downloader/niconico.py

@@ -0,0 +1,54 @@
+# coding: utf-8
+from __future__ import unicode_literals
+
+import threading
+
+from .common import FileDownloader
+from ..downloader import _get_real_downloader
+from ..extractor.niconico import NiconicoIE
+from ..compat import compat_urllib_request
+
+
+class NiconicoDmcFD(FileDownloader):
+    """ Downloading niconico douga from DMC with heartbeat """
+
+    FD_NAME = 'niconico_dmc'
+
+    def real_download(self, filename, info_dict):
+        self.to_screen('[%s] Downloading from DMC' % self.FD_NAME)
+
+        ie = NiconicoIE(self.ydl)
+        info_dict, heartbeat_info_dict = ie._get_heartbeat_info(info_dict)
+
+        fd = _get_real_downloader(info_dict, params=self.params)(self.ydl, self.params)
+
+        success = download_complete = False
+        timer = [None]
+
+        heartbeat_lock = threading.Lock()
+        heartbeat_url = heartbeat_info_dict['url']
+        heartbeat_data = heartbeat_info_dict['data']
+        heartbeat_interval = heartbeat_info_dict.get('interval', 30)
+        self.to_screen('[%s] Heartbeat with %s second interval...' % (self.FD_NAME, heartbeat_interval))
+
+        def heartbeat():
+            try:
+                compat_urllib_request.urlopen(url=heartbeat_url, data=heartbeat_data.encode())
+            except Exception:
+                self.to_screen('[%s] Heartbeat failed' % self.FD_NAME)
+
+            with heartbeat_lock:
+                if not download_complete:
+                    timer[0] = threading.Timer(heartbeat_interval, heartbeat)
+                    timer[0].start()
+
+        try:
+            heartbeat()
+            success = fd.real_download(filename, info_dict)
+        finally:
+            if heartbeat_lock:
+                with heartbeat_lock:
+                    timer[0].cancel()
+                    download_complete = True
+
+            return success

youtube_dlc/extractor/niconico.py

@@ -1,25 +1,25 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
-import datetime
+import re
-import functools
 import json
-import math
+import datetime
 
 from .common import InfoExtractor
+from ..postprocessor.ffmpeg import FFmpegPostProcessor
 from ..compat import (
     compat_parse_qs,
     compat_urllib_parse_urlparse,
 )
 from ..utils import (
-    determine_ext,
     dict_get,
     ExtractorError,
-    float_or_none,
-    InAdvancePagedList,
     int_or_none,
+    float_or_none,
+    OnDemandPagedList,
     parse_duration,
     parse_iso8601,
+    PostProcessingError,
     remove_start,
     try_get,
     unified_timestamp,
@@ -191,37 +191,87 @@ class NiconicoIE(InfoExtractor):
             self._downloader.report_warning('unable to log in: bad username or password')
         return login_ok
 
-    def _extract_format_for_quality(self, api_data, video_id, audio_quality, video_quality):
+    def _get_heartbeat_info(self, info_dict):
-        def yesno(boolean):
-            return 'yes' if boolean else 'no'
 
-        session_api_data = api_data['video']['dmcInfo']['session_api']
+        video_id, video_src_id, audio_src_id = info_dict['url'].split(':')[1].split('/')
-        session_api_endpoint = session_api_data['urls'][0]
 
-        format_id = '-'.join(map(lambda s: remove_start(s['id'], 'archive_'), [video_quality, audio_quality]))
+        # Get video webpage for API data.
+        webpage, handle = self._download_webpage_handle(
+            'http://www.nicovideo.jp/watch/' + video_id, video_id)
+
+        api_data = self._parse_json(self._html_search_regex(
+            'data-api-data="([^"]+)"', webpage,
+            'API data', default='{}'), video_id)
+
+        session_api_data = try_get(api_data, lambda x: x['video']['dmcInfo']['session_api'])
+        session_api_endpoint = try_get(session_api_data, lambda x: x['urls'][0])
+
+        # ping
+        self._download_json(
+            'https://nvapi.nicovideo.jp/v1/2ab0cbaa/watch', video_id,
+            query={'t': try_get(api_data, lambda x: x['video']['dmcInfo']['tracking_id'])},
+            headers={
+                'Origin': 'https://www.nicovideo.jp',
+                'Referer': 'https://www.nicovideo.jp/watch/' + video_id,
+                'X-Frontend-Id': '6',
+                'X-Frontend-Version': '0'
+            })
+
+        yesno = lambda x: 'yes' if x else 'no'
+
+        # m3u8 (encryption)
+        if 'encryption' in try_get(api_data, lambda x: x['video']['dmcInfo']) or {}:
+            protocol = 'm3u8'
+            session_api_http_parameters = {
+                'parameters': {
+                    'hls_parameters': {
+                        'encryption': {
+                            'hls_encryption_v1': {
+                                'encrypted_key': try_get(api_data, lambda x: x['video']['dmcInfo']['encryption']['hls_encryption_v1']['encrypted_key']),
+                                'key_uri': try_get(api_data, lambda x: x['video']['dmcInfo']['encryption']['hls_encryption_v1']['key_uri'])
+                            }
+                        },
+                        'transfer_preset': '',
+                        'use_ssl': yesno(session_api_endpoint['is_ssl']),
+                        'use_well_known_port': yesno(session_api_endpoint['is_well_known_port']),
+                        'segment_duration': 6000
+                    }
+                }
+            }
+        # http
+        else:
+            protocol = 'http'
+            session_api_http_parameters = {
+                'parameters': {
+                    'http_output_download_parameters': {
+                        'use_ssl': yesno(session_api_endpoint['is_ssl']),
+                        'use_well_known_port': yesno(session_api_endpoint['is_well_known_port']),
+                    }
+                }
+            }
 
         session_response = self._download_json(
             session_api_endpoint['url'], video_id,
             query={'_format': 'json'},
             headers={'Content-Type': 'application/json'},
-            note='Downloading JSON metadata for %s' % format_id,
+            note='Downloading JSON metadata for %s' % info_dict['format_id'],
             data=json.dumps({
                 'session': {
                     'client_info': {
-                        'player_id': session_api_data['player_id'],
+                        'player_id': session_api_data.get('player_id'),
                     },
                     'content_auth': {
-                        'auth_type': session_api_data['auth_types'][session_api_data['protocols'][0]],
+                        'auth_type': try_get(session_api_data, lambda x: x['auth_types'][session_api_data['protocols'][0]]),
-                        'content_key_timeout': session_api_data['content_key_timeout'],
+                        'content_key_timeout': session_api_data.get('content_key_timeout'),
                         'service_id': 'nicovideo',
-                        'service_user_id': session_api_data['service_user_id']
+                        'service_user_id': session_api_data.get('service_user_id')
                     },
-                    'content_id': session_api_data['content_id'],
+                    'content_id': session_api_data.get('content_id'),
                     'content_src_id_sets': [{
                         'content_src_ids': [{
                             'src_id_to_mux': {
-                                'audio_src_ids': [audio_quality['id']],
+                                'audio_src_ids': [audio_src_id],
-                                'video_src_ids': [video_quality['id']],
+                                'video_src_ids': [video_src_id],
                             }
                         }]
                     }],
@@ -229,52 +279,78 @@ class NiconicoIE(InfoExtractor):
                     'content_uri': '',
                     'keep_method': {
                         'heartbeat': {
-                            'lifetime': session_api_data['heartbeat_lifetime']
+                            'lifetime': session_api_data.get('heartbeat_lifetime')
                         }
                     },
-                    'priority': session_api_data['priority'],
+                    'priority': session_api_data.get('priority'),
                     'protocol': {
                         'name': 'http',
                         'parameters': {
-                            'http_parameters': {
+                            'http_parameters': session_api_http_parameters
-                                'parameters': {
-                                    'http_output_download_parameters': {
-                                        'use_ssl': yesno(session_api_endpoint['is_ssl']),
-                                        'use_well_known_port': yesno(session_api_endpoint['is_well_known_port']),
-                                    }
-                                }
-                            }
                         }
                     },
-                    'recipe_id': session_api_data['recipe_id'],
+                    'recipe_id': session_api_data.get('recipe_id'),
                     'session_operation_auth': {
                         'session_operation_auth_by_signature': {
-                            'signature': session_api_data['signature'],
+                            'signature': session_api_data.get('signature'),
-                            'token': session_api_data['token'],
+                            'token': session_api_data.get('token'),
                         }
                     },
                     'timing_constraint': 'unlimited'
                 }
             }).encode())
 
-        resolution = video_quality.get('resolution', {})
+        info_dict['url'] = session_response['data']['session']['content_uri']
+        info_dict['protocol'] = protocol
+
+        # get heartbeat info
+        heartbeat_info_dict = {
+            'url': session_api_endpoint['url'] + '/' + session_response['data']['session']['id'] + '?_format=json&_method=PUT',
+            'data': json.dumps(session_response['data']),
+            # interval, convert milliseconds to seconds, then halve to make a buffer.
+            'interval': float_or_none(session_api_data.get('heartbeat_lifetime'), scale=2000),
+        }
+
+        return info_dict, heartbeat_info_dict
+
+    def _extract_format_for_quality(self, api_data, video_id, audio_quality, video_quality):
+        def parse_format_id(id_code):
+            mobj = re.match(r'''(?x)
+                    (?:archive_)?
+                    (?:(?P<codec>[^_]+)_)?
+                    (?:(?P<br>[\d]+)kbps_)?
+                    (?:(?P<res>[\d+]+)p_)?
+                ''', '%s_' % id_code)
+            return mobj.groupdict() if mobj else {}
+
+        protocol = 'niconico_dmc'
+        format_id = '-'.join(map(lambda s: remove_start(s['id'], 'archive_'), [video_quality, audio_quality]))
+        vdict = parse_format_id(video_quality['id'])
+        adict = parse_format_id(audio_quality['id'])
+        resolution = video_quality.get('resolution', {'height': vdict.get('res')})
 
         return {
-            'url': session_response['data']['session']['content_uri'],
+            'url': '%s:%s/%s/%s' % (protocol, video_id, video_quality['id'], audio_quality['id']),
             'format_id': format_id,
             'ext': 'mp4',  # Session API are used in HTML5, which always serves mp4
-            'abr': float_or_none(audio_quality.get('bitrate'), 1000),
+            'vcodec': vdict.get('codec'),
-            'vbr': float_or_none(video_quality.get('bitrate'), 1000),
+            'acodec': adict.get('codec'),
-            'height': resolution.get('height'),
+            'vbr': float_or_none(video_quality.get('bitrate'), 1000) or float_or_none(vdict.get('br')),
-            'width': resolution.get('width'),
+            'abr': float_or_none(audio_quality.get('bitrate'), 1000) or float_or_none(adict.get('br')),
+            'height': int_or_none(resolution.get('height', vdict.get('res'))),
+            'width': int_or_none(resolution.get('width')),
+            'quality': -2 if 'low' in format_id else -1,  # Default quality value is -1
+            'protocol': protocol,
+            'http_headers': {
+                'Origin': 'https://www.nicovideo.jp',
+                'Referer': 'https://www.nicovideo.jp/watch/' + video_id,
+            }
         }
 
     def _real_extract(self, url):
         video_id = self._match_id(url)
 
-        # Get video webpage. We are not actually interested in it for normal
+        # Get video webpage for API data.
-        # cases, but need the cookies in order to be able to download the
-        # info webpage
         webpage, handle = self._download_webpage_handle(
             'http://www.nicovideo.jp/watch/' + video_id, video_id)
         if video_id.startswith('so'):
@@ -284,36 +360,15 @@ class NiconicoIE(InfoExtractor):
             'data-api-data="([^"]+)"', webpage,
             'API data', default='{}'), video_id)
 
-        def _format_id_from_url(video_url):
+        def get_video_info_web(items):
-            return 'economy' if video_real_url.endswith('low') else 'normal'
+            return dict_get(api_data['video'], items)
-
-        try:
-            video_real_url = api_data['video']['smileInfo']['url']
-        except KeyError:  # Flash videos
-            # Get flv info
-            flv_info_webpage = self._download_webpage(
-                'http://flapi.nicovideo.jp/api/getflv/' + video_id + '?as3=1',
-                video_id, 'Downloading flv info')
-
-            flv_info = compat_parse_qs(flv_info_webpage)
-            if 'url' not in flv_info:
-                if 'deleted' in flv_info:
-                    raise ExtractorError('The video has been deleted.',
-                                         expected=True)
-                elif 'closed' in flv_info:
-                    raise ExtractorError('Niconico videos now require logging in',
-                                         expected=True)
-                elif 'error' in flv_info:
-                    raise ExtractorError('%s reports error: %s' % (
-                        self.IE_NAME, flv_info['error'][0]), expected=True)
-                else:
-                    raise ExtractorError('Unable to find video URL')
 
+        # Get video info
         video_info_xml = self._download_xml(
             'http://ext.nicovideo.jp/api/getthumbinfo/' + video_id,
             video_id, note='Downloading video info page')
 
-            def get_video_info(items):
+        def get_video_info_xml(items):
             if not isinstance(items, list):
                 items = [items]
             for item in items:
@@ -321,43 +376,118 @@ class NiconicoIE(InfoExtractor):
                 if ret:
                     return ret
 
-            video_real_url = flv_info['url'][0]
+        if get_video_info_xml('error'):
-
+            error_code = get_video_info_xml('code')
-            extension = get_video_info('movie_type')
-            if not extension:
-                extension = determine_ext(video_real_url)
 
-            formats = [{
+            if error_code == 'DELETED':
-                'url': video_real_url,
+                raise ExtractorError('The video has been deleted.',
-                'ext': extension,
+                                     expected=True)
-                'format_id': _format_id_from_url(video_real_url),
+            elif error_code == 'NOT_FOUND':
-            }]
+                raise ExtractorError('The video is not found.',
+                                     expected=True)
+            elif error_code == 'COMMUNITY':
+                self.to_screen('%s: The video is community members only.' % video_id)
             else:
+                raise ExtractorError('%s reports error: %s' % (self.IE_NAME, error_code))
+
+        # Start extracting video formats
         formats = []
 
-            dmc_info = api_data['video'].get('dmcInfo')
+        # Get HTML5 videos info
-            if dmc_info:  # "New" HTML5 videos
+        try:
-                quality_info = dmc_info['quality']
+            dmc_info = api_data['video']['dmcInfo']
-                for audio_quality in quality_info['audios']:
+        except KeyError:
-                    for video_quality in quality_info['videos']:
+            raise ExtractorError('The video can\'t downloaded.',
-                        if not audio_quality['available'] or not video_quality['available']:
+                                 expected=True)
+
+        quality_info = dmc_info.get('quality')
+        for audio_quality in quality_info.get('audios') or {}:
+            for video_quality in quality_info.get('videos') or {}:
+                if not audio_quality.get('available') or not video_quality.get('available'):
                     continue
                 formats.append(self._extract_format_for_quality(
                     api_data, video_id, audio_quality, video_quality))
 
-                self._sort_formats(formats)
+        # Get flv/swf info
-            else:  # "Old" HTML5 videos
+        video_real_url = try_get(api_data, lambda x: x['video']['smileInfo']['url'])
-                formats = [{
+        is_economy = video_real_url.endswith('low')
+
+        if is_economy:
+            self.report_warning('Site is currently in economy mode! You will only have access to lower quality streams')
+
+        # Invoking ffprobe to determine resolution
+        pp = FFmpegPostProcessor(self._downloader)
+        cookies = self._get_cookies('https://nicovideo.jp').output(header='', sep='; path=/; domain=nicovideo.jp;\n')
+
+        self.to_screen('%s: %s' % (video_id, 'Checking smile format with ffprobe'))
+
+        try:
+            metadata = pp.get_metadata_object(video_real_url, ['-cookies', cookies])
+        except PostProcessingError as err:
+            raise ExtractorError(err.msg, expected=True)
+
+        v_stream = a_stream = {}
+
+        # Some complex swf files doesn't have video stream (e.g. nm4809023)
+        for stream in metadata['streams']:
+            if stream['codec_type'] == 'video':
+                v_stream = stream
+            elif stream['codec_type'] == 'audio':
+                a_stream = stream
+
+        # Community restricted videos seem to have issues with the thumb API not returning anything at all
+        filesize = int(
+            (get_video_info_xml('size_high') if not is_economy else get_video_info_xml('size_low'))
+            or metadata['format']['size']
+        )
+        extension = (
+            get_video_info_xml('movie_type')
+            or 'mp4' if 'mp4' in metadata['format']['format_name'] else metadata['format']['format_name']
+        )
+
+        # 'creation_time' tag on video stream of re-encoded SMILEVIDEO mp4 files are '1970-01-01T00:00:00.000000Z'.
+        timestamp = (
+            parse_iso8601(get_video_info_web('first_retrieve'))
+            or unified_timestamp(get_video_info_web('postedDateTime'))
+        )
+        metadata_timestamp = (
+            parse_iso8601(try_get(v_stream, lambda x: x['tags']['creation_time']))
+            or timestamp if extension != 'mp4' else 0
+        )
+
+        # According to compconf, smile videos from pre-2017 are always better quality than their DMC counterparts
+        smile_threshold_timestamp = parse_iso8601('2016-12-08T00:00:00+09:00')
+
+        is_source = timestamp < smile_threshold_timestamp or metadata_timestamp > 0
+
+        # If movie file size is unstable, old server movie is not source movie.
+        if filesize > 1:
+            formats.append({
                 'url': video_real_url,
-                    'ext': 'mp4',
+                'format_id': 'smile' if not is_economy else 'smile_low',
-                    'format_id': _format_id_from_url(video_real_url),
+                'format_note': 'SMILEVIDEO source' if not is_economy else 'SMILEVIDEO low quality',
-                }]
+                'ext': extension,
+                'container': extension,
+                'vcodec': v_stream.get('codec_name'),
+                'acodec': a_stream.get('codec_name'),
+                # Some complex swf files doesn't have total bit rate metadata (e.g. nm6049209)
+                'tbr': int_or_none(metadata['format'].get('bit_rate'), scale=1000),
+                'vbr': int_or_none(v_stream.get('bit_rate'), scale=1000),
+                'abr': int_or_none(a_stream.get('bit_rate'), scale=1000),
+                'height': int_or_none(v_stream.get('height')),
+                'width': int_or_none(v_stream.get('width')),
+                'source_preference': 5 if not is_economy else -2,
+                'quality': 5 if is_source and not is_economy else None,
+                'filesize': filesize
+            })
 
-            def get_video_info(items):
+        if len(formats) == 0:
-                return dict_get(api_data['video'], items)
+            raise ExtractorError('Unable to find video info.')
+
+        self._sort_formats(formats)
 
         # Start extracting information
-        title = get_video_info('title')
+        title = get_video_info_web('originalTitle')
         if not title:
             title = self._og_search_title(webpage, default=None)
         if not title:
@@ -372,14 +502,13 @@ class NiconicoIE(InfoExtractor):
         video_detail = watch_api_data.get('videoDetail', {})
 
         thumbnail = (
-            get_video_info(['thumbnail_url', 'thumbnailURL'])
+            self._html_search_regex(r'<meta property="og:image" content="([^"]+)">', webpage, 'thumbnail data', default=None)
+            or get_video_info_web(['thumbnail_url', 'largeThumbnailURL', 'thumbnailURL'])
             or self._html_search_meta('image', webpage, 'thumbnail', default=None)
             or video_detail.get('thumbnail'))
 
-        description = get_video_info('description')
+        description = get_video_info_web('description')
 
-        timestamp = (parse_iso8601(get_video_info('first_retrieve'))
-                     or unified_timestamp(get_video_info('postedDateTime')))
         if not timestamp:
             match = self._html_search_meta('datePublished', webpage, 'date published', default=None)
             if match:
@@ -389,7 +518,7 @@ class NiconicoIE(InfoExtractor):
                 video_detail['postedAt'].replace('/', '-'),
                 delimiter=' ', timezone=datetime.timedelta(hours=9))
 
-        view_count = int_or_none(get_video_info(['view_counter', 'viewCount']))
+        view_count = int_or_none(get_video_info_web(['view_counter', 'viewCount']))
         if not view_count:
             match = self._html_search_regex(
                 r'>Views: <strong[^>]*>([^<]+)</strong>',
@@ -398,7 +527,7 @@ class NiconicoIE(InfoExtractor):
                 view_count = int_or_none(match.replace(',', ''))
         view_count = view_count or video_detail.get('viewCount')
 
-        comment_count = (int_or_none(get_video_info('comment_num'))
+        comment_count = (int_or_none(get_video_info_web('comment_num'))
                          or video_detail.get('commentCount')
                          or try_get(api_data, lambda x: x['thread']['commentCount']))
         if not comment_count:
@@ -409,19 +538,19 @@ class NiconicoIE(InfoExtractor):
                 comment_count = int_or_none(match.replace(',', ''))
 
         duration = (parse_duration(
-            get_video_info('length')
+            get_video_info_web('length')
             or self._html_search_meta(
                 'video:duration', webpage, 'video duration', default=None))
             or video_detail.get('length')
-            or get_video_info('duration'))
+            or get_video_info_web('duration'))
 
-        webpage_url = get_video_info('watch_url') or url
+        webpage_url = get_video_info_web('watch_url') or url
 
         # Note: cannot use api_data.get('owner', {}) because owner may be set to "null"
         # in the JSON, which will cause None to be returned instead of {}.
         owner = try_get(api_data, lambda x: x.get('owner'), dict) or {}
-        uploader_id = get_video_info(['ch_id', 'user_id']) or owner.get('id')
+        uploader_id = get_video_info_web(['ch_id', 'user_id']) or owner.get('id')
-        uploader = get_video_info(['ch_name', 'user_nickname']) or owner.get('nickname')
+        uploader = get_video_info_web(['ch_name', 'user_nickname']) or owner.get('nickname')
 
         return {
             'id': video_id,
@@ -456,60 +585,45 @@ class NiconicoPlaylistIE(InfoExtractor):
         'url': 'https://www.nicovideo.jp/user/805442/mylist/27411728',
         'only_matching': True,
     }]
-    _PAGE_SIZE = 100
 
-    def _call_api(self, list_id, resource, query):
+    def _real_extract(self, url):
+        list_id = self._match_id(url)
+        webpage = self._download_webpage(url, list_id)
+
+        header = self._parse_json(self._html_search_regex(
+            r'data-common-header="([^"]+)"', webpage,
+            'webpage header'), list_id)
+        frontendId = header.get('initConfig').get('frontendId')
+        frontendVersion = header.get('initConfig').get('frontendVersion')
+
+        def get_page_data(pagenum, pagesize):
             return self._download_json(
-            'https://nvapi.nicovideo.jp/v2/mylists/' + list_id, list_id,
+                'http://nvapi.nicovideo.jp/v2/mylists/' + list_id, list_id,
-            'Downloading %s JSON metatdata' % resource, query=query,
+                query={'page': 1 + pagenum, 'pageSize': pagesize},
-            headers={'X-Frontend-Id': 6})['data']['mylist']
+                headers={
+                    'X-Frontend-Id': frontendId,
+                    'X-Frontend-Version': frontendVersion,
+                }).get('data').get('mylist')
+
+        data = get_page_data(0, 1)
+        title = data.get('name')
+        description = data.get('description')
+        uploader = data.get('owner').get('name')
+        uploader_id = data.get('owner').get('id')
+
+        def pagefunc(pagenum):
+            data = get_page_data(pagenum, 25)
+            return ({
+                '_type': 'url',
+                'url': 'http://www.nicovideo.jp/watch/' + item.get('watchId'),
+            } for item in data.get('items'))
 
-    def _parse_owner(self, item):
-        owner = item.get('owner') or {}
-        if owner:
         return {
-                'uploader': owner.get('name'),
+            '_type': 'playlist',
-                'uploader_id': owner.get('id'),
+            'id': list_id,
-            }
+            'title': title,
-        return {}
+            'description': description,
-
+            'uploader': uploader,
-    def _fetch_page(self, list_id, page):
+            'uploader_id': uploader_id,
-        page += 1
+            'entries': OnDemandPagedList(pagefunc, 25),
-        items = self._call_api(list_id, 'page %d' % page, {
-            'page': page,
-            'pageSize': self._PAGE_SIZE,
-        })['items']
-        for item in items:
-            video = item.get('video') or {}
-            video_id = video.get('id')
-            if not video_id:
-                continue
-            count = video.get('count') or {}
-            get_count = lambda x: int_or_none(count.get(x))
-            info = {
-                '_type': 'url',
-                'id': video_id,
-                'title': video.get('title'),
-                'url': 'https://www.nicovideo.jp/watch/' + video_id,
-                'description': video.get('shortDescription'),
-                'duration': int_or_none(video.get('duration')),
-                'view_count': get_count('view'),
-                'comment_count': get_count('comment'),
-                'ie_key': NiconicoIE.ie_key(),
         }
-            info.update(self._parse_owner(video))
-            yield info
-
-    def _real_extract(self, url):
-        list_id = self._match_id(url)
-        mylist = self._call_api(list_id, 'list', {
-            'pageSize': 1,
-        })
-        entries = InAdvancePagedList(
-            functools.partial(self._fetch_page, list_id),
-            math.ceil(mylist['totalItemCount'] / self._PAGE_SIZE),
-            self._PAGE_SIZE)
-        result = self.playlist_result(
-            entries, list_id, mylist.get('name'), mylist.get('description'))
-        result.update(self._parse_owner(mylist))
-        return result