[nrk] Workaround geo restriction and improve error messages

youtube_dl/extractor/nrk.py

@@ -1,6 +1,7 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
+import random
 import re
 
 from .common import InfoExtractor
@@ -14,6 +15,24 @@
 
 
 class NRKBaseIE(InfoExtractor):
+    _faked_ip = None
+
+    def _download_webpage(self, *args, **kwargs):
+        # NRK checks X-Forwarded-For HTTP header in order to figure out the
+        # origin of the client behind proxy. This allows to bypass geo
+        # restriction by faking this header's value to some Norway IP.
+        # We will do so once we encounter any geo restriction error.
+        if self._faked_ip:
+            kwargs.setdefault('headers', {})['X-Forwarded-For'] = self._faked_ip
+        return super(NRKBaseIE, self)._download_webpage(*args, **kwargs)
+
+    def _fake_ip(self):
+        # Use fake IP from 37.191.128.0/17 in order to workaround geo
+        # restriction
+        def octet(lb=0, ub=255):
+            return random.randint(lb, ub)
+        self._faked_ip = '37.191.%d.%d' % (octet(128), octet())
+
     def _real_extract(self, url):
         video_id = self._match_id(url)
 
@@ -70,10 +89,22 @@ def video_id_and_title(idx):
                 }]
 
         if not entries:
-            if data.get('usageRights', {}).get('isGeoBlocked'):
-                raise ExtractorError(
-                    'NRK har ikke rettigheter til å vise dette programmet utenfor Norge',
-                    expected=True)
+            message_type = data.get('messageType')
+            if message_type == 'ProgramIsGeoBlocked' and not self._faked_ip:
+                self.report_warning(
+                    'Video is geo restricted, trying to fake IP')
+                self._fake_ip()
+                return self._real_extract(url)
+
+            MESSAGES = {
+                'ProgramRightsAreNotReady': 'Du kan dessverre ikke se eller høre programmet',
+                'ProgramRightsHasExpired': 'Programmet har gått ut',
+                'ProgramIsGeoBlocked': 'NRK har ikke rettigheter til å vise dette programmet utenfor Norge',
+            }
+            raise ExtractorError(
+                '%s said: %s' % (self.IE_NAME, MESSAGES.get(
+                    message_type, message_type)),
+                expected=True)
 
         conviva = data.get('convivaStatistics') or {}
         series = conviva.get('seriesName') or data.get('seriesTitle')