[MicrosoftStream] Fixed code style and refactor

youtube_dl/extractor/microsoftstream.py

@@ -17,11 +17,36 @@ class MicrosoftStreamBaseIE(InfoExtractor):
         if username is not None or password is not None:
             raise ExtractorError('MicrosoftStream Extractor does not support username/password log-in at the moment. Please use cookies log-in instead. See https://github.com/ytdl-org/youtube-dl/blob/master/README.md#how-do-i-pass-cookies-to-youtube-dl for more information')
 
+    """
+     Extraction Helper
+    """
+
+    def _extract_access_token(self, webpage):
+        """
+         Extract the JWT access token with Regex
+        """
+        self._ACCESS_TOKEN = self._html_search_regex(r"\"AccessToken\":\"(?P<AccessToken>.+?)\"", webpage, 'AccessToken')
+        return self._ACCESS_TOKEN
+
+    def _extract_api_gateway(self, webpage):
+        """
+         Extract the API gateway with Regex
+        """
+        self._API_GATEWAY = self._html_search_regex(r"\"ApiGatewayUri\":\"(?P<APIGateway>.+?)\"", webpage, 'APIGateway')
+        return self._API_GATEWAY
+
 
 class MicrosoftStreamIE(MicrosoftStreamBaseIE):
+    """
+     Extract of single Microsoft Stream video
+    """
     IE_NAME = 'microsoftstream'
     _VALID_URL = r'https?://(?:(?:web|www)\.)?microsoftstream\.com/video/(?P<id>[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})'  # https://regex101.com/r/K1mlgK/1/
     _NETRC_MACHINE = 'microsoftstream'
+    _ACCESS_TOKEN = None  # A JWT token
+    _API_GATEWAY = None
+    _TEXTTRACKS_RESPONSE = None
+    _VIDEO_ID = None
 
     _TEST = {
         'url': 'https://web.microsoftstream.com/video/c883c6a5-9895-4900-9a35-62f4b5d506c9',
@@ -33,42 +58,49 @@ class MicrosoftStreamIE(MicrosoftStreamBaseIE):
         }
     }
 
-    def _remap_thumbnails(self, thumbnail_dict_list):
-        output = []
-        preference_index = ['extraSmall', 'small', 'medium', 'large']
-
-        for _, key in enumerate(thumbnail_dict_list):
-            output.append({
-                'preference': preference_index.index(key),
-                'url': thumbnail_dict_list[key]['url']
-            })
-        return output
-
-    def _remap_playback(self, master_playlist_urls, video_id, http_headers={}):
     """
-         A parser for the HLS and MPD playlists from the API endpoint.
+     Getters
+
+     The following getters include helpful message to prompt developers for potential errors.
     """
-        output = []
+    @property
+    def api_gateway(self):
+        if self._API_GATEWAY is None:
+            raise ExtractorError('API gateway is None. Did you forget to call "_extract_api_gateway"?')
+        return self._API_GATEWAY
 
-        for master_playlist_url in master_playlist_urls:
-            # Handle HLS Master playlist
-            if self._determine_protocol(master_playlist_url['mimeType']) == 'm3u8':
-                varient_playlists = self._extract_m3u8_formats(master_playlist_url['playbackUrl'], video_id, headers=http_headers)
+    @property
+    def access_token(self):
+        if self._ACCESS_TOKEN is None:
+            raise ExtractorError('Access token is None. Did you forget to call "_extract_access_token"?')
 
-            # For MPEG-DASH Master playlists
-            elif self._determine_protocol(master_playlist_url['mimeType']) == 'http_dash_segments':
-                varient_playlists = self._extract_mpd_formats(master_playlist_url['playbackUrl'], video_id, headers=http_headers)
+        return self._ACCESS_TOKEN
 
-            else:
-                self.to_screen('Found unresolvable stream with format %s' % master_playlist_url['mimeType'])
-                continue
+    @property
+    def video_id(self):
+        if self._VIDEO_ID is None:
+            raise('Variable "_VIDEO_ID" is not defined. Did you make the main extraction call?')
+        return self._VIDEO_ID
 
-            # Patching the "Authorization" header
-            for varient_playlist in varient_playlists:
-                varient_playlist['http_headers'] = http_headers
-                output.append(varient_playlist)
+    @property
+    def headers(self):
+        return {'Authorization': 'Bearer %s' % self.access_token}
 
-        return output
+    @property
+    def texttrack_info_endpoint(self):
+        return "%s/videos/%s/texttracks?api-version=1.3-private" % (self.api_gateway, self.video_id)
+
+    @property
+    def media_info_endpoint(self):
+        return "%s/videos/%s?$expand=creator,tokens,status,liveEvent,extensions&api-version=1.3-private" % (self.api_gateway, self.video_id)
+
+    def _request_texttracks(self):
+        """
+         Make an additional request to Microsoft Stream for the subtitle and auto-caption
+        """
+        # Map default variable
+        self._TEXTTRACKS_RESPONSE = self._download_json(self.texttrack_info_endpoint, self.video_id, headers=self.headers)['value']
+        return self._TEXTTRACKS_RESPONSE
 
     def _determine_protocol(self, mime):
         """
@@ -81,53 +113,100 @@ class MicrosoftStreamIE(MicrosoftStreamBaseIE):
         else:
             return None
 
-    def _remap_texttracks(self, tracks):
+    def _remap_thumbnails(self, thumbnail_dict_list):
+        output = []
+        preference_index = ['extraSmall', 'small', 'medium', 'large']
+
+        for _, key in enumerate(thumbnail_dict_list):
+            output.append({
+                'preference': preference_index.index(key),
+                'url': thumbnail_dict_list.get(key).get('url')
+            })
+        return output
+
+    def _remap_playback(self, master_playlist_urls):
         """
-         A parser for the texttracks response.
+         A parser for the HLS and MPD playlists from the API endpoint.
         """
-        subtitle = {}
-        automatic_captions = {}
-        for track in tracks:
-            if track['autoGenerated'] is True:
-                if track['language'] not in automatic_captions:
-                    automatic_captions[track['language']] = []
-                automatic_captions[track['language']].append({'url': track['url']})
+        output = []
+
+        for master_playlist_url in master_playlist_urls:
+            protocol = self._determine_protocol(master_playlist_url['mimeType'])
+            # Handle HLS Master playlist
+            if protocol == 'm3u8':
+                varient_playlists = self._extract_m3u8_formats(master_playlist_url['playbackUrl'], video_id=self.video_id, headers=self.headers)
+
+            # For MPEG-DASH Master playlists
+            elif protocol == 'http_dash_segments':
+                varient_playlists = self._extract_mpd_formats(master_playlist_url['playbackUrl'], video_id=self.video_id, headers=self.headers)
+
+            # For other Master playlists (like Microsoft Smooth Streaming)
             else:
-                if track['language'] not in subtitle:
-                    subtitle[track['language']] = []
-                subtitle[track['language']].append({'url': track['url']})
-        return (subtitle, automatic_captions)
+                self.to_screen('Found unresolvable stream with format %s' % master_playlist_url['mimeType'])
+                continue
+
+            # Patching the "Authorization" header
+            for varient_playlist in varient_playlists:
+                varient_playlist['http_headers'] = self.headers
+                output.append(varient_playlist)
+        return output
+
+    def _extract_subtitle(self, tracks, is_auto_generated):
+        """
+         An internal method for filtering and remapping text tracks
+        """
+        if type(is_auto_generated) is not bool:
+            raise ExtractorError('Unexpected variable "is_auto_generated" type: must be a Boolean')
+
+        subtitle_subset = {}
+
+        for track in tracks:
+            track_language = track.get('language')           # The track language must have a language code.
+
+            if track.get('autoGenerated') is is_auto_generated:
+                if track_language not in subtitle_subset:
+                    subtitle_subset[track_language] = []     # Scaffold an empty list for the object to insert into
+
+                # Since the subtitle is token protected, a get request will fire here.
+                data = self._download_webpage(url_or_request=track.get('url'), video_id=self.video_id, headers=self.headers)
+                subtitle_subset[track_language].append({'data': data, "ext": "vtt"})
+
+        return subtitle_subset
+
+    def _get_subtitles(self, tracks=None):                        # Fulfill abstract method
+        tracks = self._TEXTTRACKS_RESPONSE if tracks is None else tracks
+        return self._extract_subtitle(tracks, False)
+
+    def _get_automatic_captions(self, tracks=None):               # Fulfill abstract method
+        tracks = self._TEXTTRACKS_RESPONSE if tracks is None else tracks
+        return self._extract_subtitle(tracks, True)
 
     def _real_extract(self, url):
-        video_id = self._match_id(url)
-        webpage = self._download_webpage(url, video_id)
+        self._VIDEO_ID = self._match_id(url)
+        webpage = self._download_webpage(url, self.video_id)
 
         if not self.is_logged_in(webpage):
             return self.raise_login_required()
 
         # Extract access token from webpage
-        accessToken = self._html_search_regex(r"\"AccessToken\":\"(?P<AccessToken>.+?)\"", webpage, 'AccessToken')
-        apiGateway = self._html_search_regex(r"\"ApiGatewayUri\":\"(?P<APIGateway>.+?)\"", webpage, 'APIGateway')
-        headers = {'Authorization': 'Bearer %s' % accessToken}
+        self._extract_access_token(webpage)
+        self._extract_api_gateway(webpage)
 
         # "GET" api for video information
-        apiUri = "%s/videos/%s?$expand=creator,tokens,status,liveEvent,extensions&api-version=1.3-private" % (apiGateway, video_id)
-        apiCall = self._download_json(apiUri, video_id, headers=headers)
+        apiUri = self.media_info_endpoint
+        apiCall = self._download_json(apiUri, self.video_id, headers=self.headers)
 
-        # "GET" api for subtitles and auto-captions
-        texttracksUri = "%s/videos/%s/texttracks?api-version=1.3-private" % (apiGateway, video_id)
-        texttracksCall = self._download_json(texttracksUri, video_id, headers=headers)['value']
-        subtitles, automatic_captions = self._remap_texttracks(texttracksCall)
+        texttracks = self._request_texttracks()
 
         return {
-            'id': video_id,
+            'id': self.video_id,
             'title': apiCall['name'],
-            'description': apiCall['description'],
-            'uploader': apiCall['creator']['name'],
-            'thumbnails': self._remap_thumbnails(apiCall['posterImage']),
-            'formats': self._remap_playback(apiCall['playbackUrls'], video_id, http_headers=headers),
-            'subtitles': subtitles,
-            'automatic_captions': automatic_captions,
+            'description': apiCall.get('description'),
+            'uploader': apiCall.get('creator').get('name'),
+            'thumbnails': self._remap_thumbnails(apiCall.get('posterImage')),
+            'formats': self._remap_playback(apiCall['playbackUrls']),
+            'subtitles': self._get_subtitles(texttracks),
+            'automatic_captions': self._get_automatic_captions(texttracks),
             'is_live': False,
             # 'duration': apiCall['media']['duration'],
         }