[nexx] Restore reverse engineered approach

youtube_dl/extractor/nexx.py

@@ -1,22 +1,27 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
+import hashlib
+import random
 import re
+import time
 
 from .common import InfoExtractor
 from ..compat import compat_str
 from ..utils import (
+    ExtractorError,
     int_or_none,
     parse_duration,
     try_get,
+    urlencode_postdata,
 )
 
 
 class NexxIE(InfoExtractor):
     _VALID_URL = r'''(?x)
                         (?:
-                            https?://api\.nexx(?:\.cloud|cdn\.com)/v3/\d+/videos/byid/|
-                            nexx:(?:\d+:)?|
+                            https?://api\.nexx(?:\.cloud|cdn\.com)/v3/(?P<domain_id>\d+)/videos/byid/|
+                            nexx:(?P<domain_id_s>\d+)?:|
                             https?://arc\.nexx\.cloud/api/video/
                         )
                         (?P<id>\d+)
@@ -57,6 +62,21 @@ class NexxIE(InfoExtractor):
         'params': {
             'skip_download': True,
         },
+    }, {
+        # does not work via arc
+        'url': 'nexx:741:1269984',
+        'md5': 'c714b5b238b2958dc8d5642addba6886',
+        'info_dict': {
+            'id': '1269984',
+            'ext': 'mp4',
+            'title': '1 TAG ohne KLO... wortwörtlich! 😑',
+            'alt_title': '1 TAG ohne KLO... wortwörtlich! 😑',
+            'description': 'md5:4604539793c49eda9443ab5c5b1d612f',
+            'thumbnail': r're:^https?://.*\.jpg$',
+            'duration': 607,
+            'timestamp': 1518614955,
+            'upload_date': '20180214',
+        },
     }, {
         'url': 'https://api.nexxcdn.com/v3/748/videos/byid/128907',
         'only_matching': True,
@@ -103,12 +123,99 @@ class NexxIE(InfoExtractor):
     def _extract_url(webpage):
         return NexxIE._extract_urls(webpage)[0]
 
+    def _handle_error(self, response):
+        status = int_or_none(try_get(
+            response, lambda x: x['metadata']['status']) or 200)
+        if 200 <= status < 300:
+            return
+        raise ExtractorError(
+            '%s said: %s' % (self.IE_NAME, response['metadata']['errorhint']),
+            expected=True)
+
+    def _call_api(self, domain_id, path, video_id, data=None, headers={}):
+        headers['Content-Type'] = 'application/x-www-form-urlencoded; charset=UTF-8'
+        result = self._download_json(
+            'https://api.nexx.cloud/v3/%s/%s' % (domain_id, path), video_id,
+            'Downloading %s JSON' % path, data=urlencode_postdata(data),
+            headers=headers)
+        self._handle_error(result)
+        return result['result']
+
     def _real_extract(self, url):
-        video_id = self._match_id(url)
+        mobj = re.match(self._VALID_URL, url)
+        domain_id = mobj.group('domain_id') or mobj.group('domain_id_s')
+        video_id = mobj.group('id')
+
+        video = None
 
-        video = self._download_json(
+        response = self._download_json(
             'https://arc.nexx.cloud/api/video/%s.json' % video_id,
-            video_id)['result']
+            video_id, fatal=False)
+        if response and isinstance(response, dict):
+            result = response.get('result')
+            if result and isinstance(result, dict):
+                video = result
+
+        # not all videos work via arc, e.g. nexx:741:1269984
+        if not video:
+            # Reverse engineered from JS code (see getDeviceID function)
+            device_id = '%d:%d:%d%d' % (
+                random.randint(1, 4), int(time.time()),
+                random.randint(1e4, 99999), random.randint(1, 9))
+
+            result = self._call_api(domain_id, 'session/init', video_id, data={
+                'nxp_devh': device_id,
+                'nxp_userh': '',
+                'precid': '0',
+                'playlicense': '0',
+                'screenx': '1920',
+                'screeny': '1080',
+                'playerversion': '6.0.00',
+                'gateway': 'html5',
+                'adGateway': '',
+                'explicitlanguage': 'en-US',
+                'addTextTemplates': '1',
+                'addDomainData': '1',
+                'addAdModel': '1',
+            }, headers={
+                'X-Request-Enable-Auth-Fallback': '1',
+            })
+
+            cid = result['general']['cid']
+
+            # As described in [1] X-Request-Token generation algorithm is
+            # as follows:
+            #   md5( operation + domain_id + domain_secret )
+            # where domain_secret is a static value that will be given by nexx.tv
+            # as per [1]. Here is how this "secret" is generated (reversed
+            # from _play.api.init function, search for clienttoken). So it's
+            # actually not static and not that much of a secret.
+            # 1. https://nexxtvstorage.blob.core.windows.net/files/201610/27.pdf
+            secret = result['device']['clienttoken'][int(device_id[0]):]
+            secret = secret[0:len(secret) - int(device_id[-1])]
+
+            op = 'byid'
+
+            # Reversed from JS code for _play.api.call function (search for
+            # X-Request-Token)
+            request_token = hashlib.md5(
+                ''.join((op, domain_id, secret)).encode('utf-8')).hexdigest()
+
+            video = self._call_api(
+                domain_id, 'videos/%s/%s' % (op, video_id), video_id, data={
+                    'additionalfields': 'language,channel,actors,studio,licenseby,slug,subtitle,teaser,description',
+                    'addInteractionOptions': '1',
+                    'addStatusDetails': '1',
+                    'addStreamDetails': '1',
+                    'addCaptions': '1',
+                    'addScenes': '1',
+                    'addHotSpots': '1',
+                    'addBumpers': '1',
+                    'captionFormat': 'data',
+                }, headers={
+                    'X-Request-CID': cid,
+                    'X-Request-Token': request_token,
+                })
 
         general = video['general']
         title = general['title']