From e5de3f6c89d2432a3afbc6d0545259ad49ee17a9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sergey=20M=E2=80=A4?= <dstftw@gmail.com>
Date: Fri, 14 Mar 2014 00:36:14 +0700
Subject: [PATCH] [udemy] Initial support for free courses (#1617)

---
 youtube_dl/extractor/__init__.py |   4 +
 youtube_dl/extractor/udemy.py    | 163 +++++++++++++++++++++++++++++++
 2 files changed, 167 insertions(+)
 create mode 100644 youtube_dl/extractor/udemy.py

diff --git a/youtube_dl/extractor/__init__.py b/youtube_dl/extractor/__init__.py
index f06b4d1dc..313414e7d 100644
--- a/youtube_dl/extractor/__init__.py
+++ b/youtube_dl/extractor/__init__.py
@@ -242,6 +242,10 @@ from .tumblr import TumblrIE
 from .tutv import TutvIE
 from .tvigle import TvigleIE
 from .tvp import TvpIE
+from .udemy import (
+    UdemyIE,
+    UdemyCourseIE
+)
 from .unistra import UnistraIE
 from .ustream import UstreamIE, UstreamChannelIE
 from .vbox7 import Vbox7IE
diff --git a/youtube_dl/extractor/udemy.py b/youtube_dl/extractor/udemy.py
new file mode 100644
index 000000000..35df918b8
--- /dev/null
+++ b/youtube_dl/extractor/udemy.py
@@ -0,0 +1,163 @@
+from __future__ import unicode_literals
+
+import re
+
+from .common import InfoExtractor
+from ..utils import (
+    compat_urllib_parse,
+    compat_urllib_request,
+    ExtractorError,
+)
+
+
+class UdemyIE(InfoExtractor):
+    IE_NAME = 'udemy'
+    _VALID_URL = r'https?://www\.udemy\.com/(?:[^#]+#/lecture/|lecture/view/?\?lectureId=)(?P<id>\d+)'
+    _LOGIN_URL = 'https://www.udemy.com/join/login-submit/'
+    _NETRC_MACHINE = 'udemy'
+
+    _TEST = {
+        'url': 'https://www.udemy.com/java-tutorial/#/lecture/172757',
+        'md5': '98eda5b657e752cf945d8445e261b5c5',
+        'info_dict': {
+            'id': '160614',
+            'ext': 'mp4',
+            'title': 'Introduction and Installation',
+            'description': 'md5:c0d51f6f21ef4ec65f091055a5eef876',
+            'duration': 579.29,
+        },
+        'skip': 'Requires udemy account credentials',
+    }
+
+    def _handle_error(self, response):
+        if not isinstance(response, dict):
+            return
+        error = response.get('error')
+        if error:
+            error_str = 'Udemy returned error #%s: %s' % (error.get('code'), error.get('message'))
+            error_data = error.get('data')
+            if error_data:
+                error_str += ' - %s' % error_data.get('formErrors')
+            raise ExtractorError(error_str, expected=True)
+
+    def _download_json(self, url, video_id, note='Downloading JSON metadata'):
+        response = super(UdemyIE, self)._download_json(url, video_id, note)
+        self._handle_error(response)
+        return response
+
+    def _real_initialize(self):
+        self._login()
+
+    def _login(self):
+        (username, password) = self._get_login_info()
+        if username is None:
+            raise ExtractorError(
+                'Udemy account is required, use --username and --password options to provide account credentials.',
+                expected=True)
+
+        login_popup = self._download_webpage(
+            'https://www.udemy.com/join/login-popup?displayType=ajax&showSkipButton=1', None,
+            'Downloading login popup')
+
+        if login_popup == '<div class="run-command close-popup redirect" data-url="https://www.udemy.com/"></div>':
+            return
+
+        csrf = self._html_search_regex(r'<input type="hidden" name="csrf" value="(.+?)"', login_popup, 'csrf token')
+
+        login_form = {
+            'email': username,
+            'password': password,
+            'csrf': csrf,
+            'displayType': 'json',
+            'isSubmitted': '1',
+        }
+        request = compat_urllib_request.Request(self._LOGIN_URL, compat_urllib_parse.urlencode(login_form))
+        response = self._download_json(request, None, 'Logging in as %s' % username)
+
+        if 'returnUrl' not in response:
+            raise ExtractorError('Unable to log in')
+
+    def _real_extract(self, url):
+        mobj = re.match(self._VALID_URL, url)
+        lecture_id = mobj.group('id')
+
+        lecture = self._download_json(
+            'https://www.udemy.com/api-1.1/lectures/%s' % lecture_id, lecture_id, 'Downloading lecture JSON')
+
+        if lecture['assetType'] != 'Video':
+            raise ExtractorError('Lecture %s is not a video' % lecture_id, expected=True)
+
+        asset = lecture['asset']
+
+        stream_url = asset['streamUrl']
+        mobj = re.search(r'(https?://www\.youtube\.com/watch\?v=.*)', stream_url)
+        if mobj:
+            return self.url_result(mobj.group(1), 'Youtube')
+
+        video_id = asset['id']
+        thumbnail = asset['thumbnailUrl']
+        duration = asset['data']['duration']
+
+        download_url = asset['downloadUrl']
+
+        formats = [
+            {
+                'url': download_url['Video480p'][0],
+                'format_id': '360p',
+            },
+            {
+                'url': download_url['Video'][0],
+                'format_id': '720p',
+            },
+        ]
+
+        title = lecture['title']
+        description = lecture['description']
+
+        return {
+            'id': video_id,
+            'title': title,
+            'description': description,
+            'thumbnail': thumbnail,
+            'duration': duration,
+            'formats': formats
+        }
+
+
+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.<'
+
+    @classmethod
+    def suitable(cls, url):
+        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')
+
+        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']
+
+        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)
+
+        response = self._download_json('https://www.udemy.com/api-1.1/courses/%s/curriculum' % course_id,
+            course_id, 'Downloading course curriculum')
+
+        entries = [
+            self.url_result('https://www.udemy.com/%s/#/lecture/%s' % (course_path, asset['id']), 'Udemy')
+            for asset in response if asset.get('assetType') == 'Video'
+        ]
+
+        return self.playlist_result(entries, course_id, course_title)
\ No newline at end of file