[mtv,cc,cmt,spike] Improve and refactor

- Eliminate _transform_rtmp_url
* Generalize triforce mgid extraction
+ [cmt] Add support for full-episodes (closes #11623)

youtube_dl/extractor/cmt.py

@@ -1,13 +1,11 @@
 from __future__ import unicode_literals
 
 from .mtv import MTVIE
-from ..utils import ExtractorError
 
 
 class CMTIE(MTVIE):
     IE_NAME = 'cmt.com'
-    _VALID_URL = r'https?://(?:www\.)?cmt\.com/(?:videos|shows)/(?:[^/]+/)*(?P<videoid>\d+)'
-    _FEED_URL = 'http://www.cmt.com/sitewide/apps/player/embed/rss/'
+    _VALID_URL = r'https?://(?:www\.)?cmt\.com/(?:videos|shows|full-episodes)/(?P<id>[^/]+)'
 
     _TESTS = [{
         'url': 'http://www.cmt.com/videos/garth-brooks/989124/the-call-featuring-trisha-yearwood.jhtml#artist=30061',
@@ -35,15 +33,16 @@ class CMTIE(MTVIE):
         'only_matching': True,
     }]
 
-    @classmethod
-    def _transform_rtmp_url(cls, rtmp_video_url):
-        if 'error_not_available.swf' in rtmp_video_url:
-            raise ExtractorError(
-                '%s said: video is not available' % cls.IE_NAME, expected=True)
-
-        return super(CMTIE, cls)._transform_rtmp_url(rtmp_video_url)
-
     def _extract_mgid(self, webpage):
-        return self._search_regex(
+        mgid = self._search_regex(
             r'MTVN\.VIDEO\.contentUri\s*=\s*([\'"])(?P<mgid>.+?)\1',
-            webpage, 'mgid', group='mgid')
+            webpage, 'mgid', group='mgid', default=None)
+        if not mgid:
+            mgid = self._extract_triforce_mgid(webpage)
+        return mgid
+
+    def _real_extract(self, url):
+        video_id = self._match_id(url)
+        webpage = self._download_webpage(url, video_id)
+        mgid = self._extract_mgid(webpage)
+        return self.url_result('http://media.mtvnservices.com/embed/%s' % mgid)