[udemy] Semi-switch to api 2.0 (Closes #7704)

* Use api 2.0 to get lectures since it provides more formats
* Fix authorization for api 2.0
* Autotry enrolling in the course for single lectures
* Extract additional metadata rom asset['data']['outputs']

youtube_dl/extractor/udemy.py

@@ -1,14 +1,15 @@
 from __future__ import unicode_literals
 
-import re
-
 from .common import InfoExtractor
 from ..compat import (
+    compat_HTTPError,
     compat_urllib_parse,
     compat_urllib_request,
+    compat_urlparse,
 )
 from ..utils import (
     ExtractorError,
+    float_or_none,
     int_or_none,
     sanitized_Request,
 )
@@ -19,6 +20,8 @@ class UdemyIE(InfoExtractor):
     _VALID_URL = r'https?://www\.udemy\.com/(?:[^#]+#/lecture/|lecture/view/?\?lectureId=)(?P<id>\d+)'
     _LOGIN_URL = 'https://www.udemy.com/join/login-popup/?displayType=ajax&showSkipButton=1'
     _ORIGIN_URL = 'https://www.udemy.com'
+    _SUCCESSFULLY_ENROLLED = '>You have enrolled in this course!<'
+    _ALREADY_ENROLLED = '>You are already taking this course.<'
     _NETRC_MACHINE = 'udemy'
 
     _TESTS = [{
@@ -34,6 +37,29 @@ class UdemyIE(InfoExtractor):
         'skip': 'Requires udemy account credentials',
     }]
 
+    def _enroll_course(self, webpage, course_id):
+        enroll_url = self._search_regex(
+            r'href=(["\'])(?P<url>https?://(?:www\.)?udemy\.com/course/subscribe/.+?)\1',
+            webpage, 'enroll url', group='url',
+            default='https://www.udemy.com/course/subscribe/?courseId=%s' % course_id)
+        webpage = self._download_webpage(enroll_url, course_id, 'Enrolling in the course')
+        if self._SUCCESSFULLY_ENROLLED in webpage:
+            self.to_screen('%s: Successfully enrolled in' % course_id)
+        elif self._ALREADY_ENROLLED in webpage:
+            self.to_screen('%s: Already enrolled in' % course_id)
+
+    def _download_lecture(self, course_id, lecture_id):
+        return self._download_json(
+            'https://www.udemy.com/api-2.0/users/me/subscribed-courses/%s/lectures/%s?%s' % (
+                course_id, lecture_id, compat_urllib_parse.urlencode({
+                    'video_only': '',
+                    'auto_play': '',
+                    'fields[lecture]': 'title,description,asset',
+                    'fields[asset]': 'asset_type,stream_url,thumbnail_url,download_urls,data',
+                    'instructorPreviewMode': 'False',
+                })),
+            lecture_id, 'Downloading lecture JSON', fatal=False)
+
     def _handle_error(self, response):
         if not isinstance(response, dict):
             return
@@ -45,7 +71,7 @@ class UdemyIE(InfoExtractor):
                 error_str += ' - %s' % error_data.get('formErrors')
             raise ExtractorError(error_str, expected=True)
 
-    def _download_json(self, url_or_request, video_id, note='Downloading JSON metadata'):
+    def _download_json(self, url_or_request, video_id, note='Downloading JSON metadata', *args, **kwargs):
         headers = {
             'X-Udemy-Snail-Case': 'true',
             'X-Requested-With': 'XMLHttpRequest',
@@ -55,6 +81,7 @@ class UdemyIE(InfoExtractor):
                 headers['X-Udemy-Client-Id'] = cookie.value
             elif cookie.name == 'access_token':
                 headers['X-Udemy-Bearer-Token'] = cookie.value
+                headers['X-Udemy-Authorization'] = 'Bearer %s' % cookie.value
 
         if isinstance(url_or_request, compat_urllib_request.Request):
             for header, value in headers.items():
@@ -62,7 +89,7 @@ class UdemyIE(InfoExtractor):
         else:
             url_or_request = sanitized_Request(url_or_request, headers=headers)
 
-        response = super(UdemyIE, self)._download_json(url_or_request, video_id, note)
+        response = super(UdemyIE, self)._download_json(url_or_request, video_id, note, *args, **kwargs)
         self._handle_error(response)
         return response
 
@@ -110,66 +137,77 @@ class UdemyIE(InfoExtractor):
     def _real_extract(self, url):
         lecture_id = self._match_id(url)
 
-        lecture = self._download_json(
-            'https://www.udemy.com/api-1.1/lectures/%s' % lecture_id,
-            lecture_id, 'Downloading lecture JSON')
+        webpage = self._download_webpage(url, lecture_id)
 
-        asset_type = lecture.get('assetType') or lecture.get('asset_type')
+        course_id = self._search_regex(
+            r'data-course-id=["\'](\d+)', webpage, 'course id')
+
+        try:
+            lecture = self._download_lecture(course_id, lecture_id)
+        except ExtractorError as e:
+            # Error could possibly mean we are not enrolled in the course
+            if isinstance(e.cause, compat_HTTPError) and e.cause.code == 403:
+                self._enroll_course(webpage, course_id)
+                lecture_id = self._download_lecture(course_id, lecture_id)
+            else:
+                raise
+
+        title = lecture['title']
+        description = lecture.get('description')
+
+        asset = lecture['asset']
+
+        asset_type = asset.get('assetType') or asset.get('asset_type')
         if asset_type != 'Video':
             raise ExtractorError(
                 'Lecture %s is not a video' % lecture_id, expected=True)
 
-        asset = lecture['asset']
-
         stream_url = asset.get('streamUrl') or asset.get('stream_url')
-        mobj = re.search(r'(https?://www\.youtube\.com/watch\?v=.*)', stream_url)
-        if mobj:
-            return self.url_result(mobj.group(1), 'Youtube')
+        if stream_url:
+            youtube_url = self._search_regex(
+                r'(https?://www\.youtube\.com/watch\?v=.*)', stream_url, 'youtube URL', default=None)
+            if youtube_url:
+                return self.url_result(youtube_url, 'Youtube')
 
         video_id = asset['id']
         thumbnail = asset.get('thumbnailUrl') or asset.get('thumbnail_url')
-        duration = int_or_none(asset.get('data', {}).get('duration'))
+        duration = float_or_none(asset.get('data', {}).get('duration'))
+        outputs = asset.get('data', {}).get('outputs', {})
 
-        download_url = asset.get('downloadUrl') or asset.get('download_url')
-
-        video = download_url.get('Video') or download_url.get('video')
-        video_480p = download_url.get('Video480p') or download_url.get('video_480p')
-
-        formats = [{
-            'url': video_480p[0],
-            'format_id': 'download-360p',
-        }, {
-            'url': video[0],
-            'format_id': 'download-720p',
-        }]
-
-        # Some videos also contain formats in asset['data']['outputs'] (e.g.
-        # https://www.udemy.com/ios9-swift/learn/#/lecture/3383208)
-        outputs = asset.get('data', {}).get('outputs')
-        if isinstance(outputs, dict):
-            for format_id, f in outputs.items():
-                video_url = f.get('url')
-                if video_url:
-                    formats.append({
-                        'url': video_url,
-                        'format_id': '%sp' % (f.get('labe1l') or format_id),
-                        'width': int_or_none(f.get('width')),
-                        'height': int_or_none(f.get('height')),
-                        'vbr': int_or_none(f.get('video_bitrate_in_kbps')),
-                        'vcodec': f.get('video_codec'),
-                        'fps': int_or_none(f.get('frame_rate')),
-                        'abr': int_or_none(f.get('audio_bitrate_in_kbps')),
-                        'acodec': f.get('audio_codec'),
-                        'asr': int_or_none(f.get('audio_sample_rate')),
-                        'tbr': int_or_none(f.get('total_bitrate_in_kbps')),
-                        'filesize': int_or_none(f.get('file_size_in_bytes')),
+        formats = []
+        for format_ in asset.get('download_urls', {}).get('Video', []):
+            video_url = format_.get('file')
+            if not video_url:
+                continue
+            format_id = format_.get('label')
+            f = {
+                'url': format_['file'],
+                'height': int_or_none(format_id),
+            }
+            if format_id:
+                # Some videos contain additional metadata (e.g.
+                # https://www.udemy.com/ios9-swift/learn/#/lecture/3383208)
+                output = outputs.get(format_id)
+                if isinstance(output, dict):
+                    f.update({
+                        'format_id': '%sp' % (output.get('label') or format_id),
+                        'width': int_or_none(output.get('width')),
+                        'height': int_or_none(output.get('height')),
+                        'vbr': int_or_none(output.get('video_bitrate_in_kbps')),
+                        'vcodec': output.get('video_codec'),
+                        'fps': int_or_none(output.get('frame_rate')),
+                        'abr': int_or_none(output.get('audio_bitrate_in_kbps')),
+                        'acodec': output.get('audio_codec'),
+                        'asr': int_or_none(output.get('audio_sample_rate')),
+                        'tbr': int_or_none(output.get('total_bitrate_in_kbps')),
+                        'filesize': int_or_none(output.get('file_size_in_bytes')),
                     })
+                else:
+                    f['format_id'] = '%sp' % format_id
+            formats.append(f)
 
         self._sort_formats(formats)
 
-        title = lecture['title']
-        description = lecture.get('description')
-
         return {
             'id': video_id,
             'title': title,
@@ -182,9 +220,7 @@ class UdemyIE(InfoExtractor):
 
 class UdemyCourseIE(UdemyIE):
     IE_NAME = 'udemy:course'
-    _VALID_URL = r'https?://www\.udemy\.com/(?P<coursepath>[\da-z-]+)'
-    _SUCCESSFULLY_ENROLLED = '>You have enrolled in this course!<'
-    _ALREADY_ENROLLED = '>You are already taking this course.<'
+    _VALID_URL = r'https?://www\.udemy\.com/(?P<id>[\da-z-]+)'
     _TESTS = []
 
     @classmethod
@@ -192,24 +228,18 @@ class UdemyCourseIE(UdemyIE):
         return False if UdemyIE.suitable(url) else super(UdemyCourseIE, cls).suitable(url)
 
     def _real_extract(self, url):
-        mobj = re.match(self._VALID_URL, url)
-        course_path = mobj.group('coursepath')
+        course_path = self._match_id(url)
+
+        webpage = self._download_webpage(url, course_path)
 
         response = self._download_json(
             'https://www.udemy.com/api-1.1/courses/%s' % course_path,
             course_path, 'Downloading course JSON')
 
-        course_id = int(response['id'])
-        course_title = response['title']
+        course_id = response['id']
+        course_title = response.get('title')
 
-        webpage = self._download_webpage(
-            'https://www.udemy.com/course/subscribe/?courseId=%s' % course_id,
-            course_id, 'Enrolling in the course')
-
-        if self._SUCCESSFULLY_ENROLLED in webpage:
-            self.to_screen('%s: Successfully enrolled in' % course_id)
-        elif self._ALREADY_ENROLLED in webpage:
-            self.to_screen('%s: Already enrolled in' % course_id)
+        self._enroll_course(webpage, course_id)
 
         response = self._download_json(
             'https://www.udemy.com/api-1.1/courses/%s/curriculum' % course_id,