Add --list-extractor-descriptions (human-readable list of IEs)
[youtube-dl] / youtube_dl / extractor / stanfordoc.py
1 import re
2 import socket
3 import xml.etree.ElementTree
4
5 from .common import InfoExtractor
6 from ..utils import (
7     compat_http_client,
8     compat_str,
9     compat_urllib_error,
10     compat_urllib_request,
11
12     ExtractorError,
13     orderedSet,
14     unescapeHTML,
15 )
16
17
18 class StanfordOpenClassroomIE(InfoExtractor):
19     IE_NAME = u'stanfordoc'
20     IE_DESC = u'Stanford Open ClassRoom'
21     _VALID_URL = r'^(?:https?://)?openclassroom.stanford.edu(?P<path>/?|(/MainFolder/(?:HomePage|CoursePage|VideoPage)\.php([?]course=(?P<course>[^&]+)(&video=(?P<video>[^&]+))?(&.*)?)?))$'
22     _TEST = {
23         u'url': u'http://openclassroom.stanford.edu/MainFolder/VideoPage.php?course=PracticalUnix&video=intro-environment&speed=100',
24         u'file': u'PracticalUnix_intro-environment.mp4',
25         u'md5': u'544a9468546059d4e80d76265b0443b8',
26         u'info_dict': {
27             u"title": u"Intro Environment"
28         }
29     }
30
31     def _real_extract(self, url):
32         mobj = re.match(self._VALID_URL, url)
33         if mobj is None:
34             raise ExtractorError(u'Invalid URL: %s' % url)
35
36         if mobj.group('course') and mobj.group('video'): # A specific video
37             course = mobj.group('course')
38             video = mobj.group('video')
39             info = {
40                 'id': course + '_' + video,
41                 'uploader': None,
42                 'upload_date': None,
43             }
44
45             self.report_extraction(info['id'])
46             baseUrl = 'http://openclassroom.stanford.edu/MainFolder/courses/' + course + '/videos/'
47             xmlUrl = baseUrl + video + '.xml'
48             try:
49                 metaXml = compat_urllib_request.urlopen(xmlUrl).read()
50             except (compat_urllib_error.URLError, compat_http_client.HTTPException, socket.error) as err:
51                 raise ExtractorError(u'Unable to download video info XML: %s' % compat_str(err))
52             mdoc = xml.etree.ElementTree.fromstring(metaXml)
53             try:
54                 info['title'] = mdoc.findall('./title')[0].text
55                 info['url'] = baseUrl + mdoc.findall('./videoFile')[0].text
56             except IndexError:
57                 raise ExtractorError(u'Invalid metadata XML file')
58             info['ext'] = info['url'].rpartition('.')[2]
59             return [info]
60         elif mobj.group('course'): # A course page
61             course = mobj.group('course')
62             info = {
63                 'id': course,
64                 'type': 'playlist',
65                 'uploader': None,
66                 'upload_date': None,
67             }
68
69             coursepage = self._download_webpage(url, info['id'],
70                                         note='Downloading course info page',
71                                         errnote='Unable to download course info page')
72
73             info['title'] = self._html_search_regex('<h1>([^<]+)</h1>', coursepage, 'title', default=info['id'])
74
75             info['description'] = self._html_search_regex('<description>([^<]+)</description>',
76                 coursepage, u'description', fatal=False)
77
78             links = orderedSet(re.findall('<a href="(VideoPage.php\?[^"]+)">', coursepage))
79             info['list'] = [
80                 {
81                     'type': 'reference',
82                     'url': 'http://openclassroom.stanford.edu/MainFolder/' + unescapeHTML(vpage),
83                 }
84                     for vpage in links]
85             results = []
86             for entry in info['list']:
87                 assert entry['type'] == 'reference'
88                 results += self.extract(entry['url'])
89             return results
90         else: # Root page
91             info = {
92                 'id': 'Stanford OpenClassroom',
93                 'type': 'playlist',
94                 'uploader': None,
95                 'upload_date': None,
96             }
97
98             self.report_download_webpage(info['id'])
99             rootURL = 'http://openclassroom.stanford.edu/MainFolder/HomePage.php'
100             try:
101                 rootpage = compat_urllib_request.urlopen(rootURL).read()
102             except (compat_urllib_error.URLError, compat_http_client.HTTPException, socket.error) as err:
103                 raise ExtractorError(u'Unable to download course info page: ' + compat_str(err))
104
105             info['title'] = info['id']
106
107             links = orderedSet(re.findall('<a href="(CoursePage.php\?[^"]+)">', rootpage))
108             info['list'] = [
109                 {
110                     'type': 'reference',
111                     'url': 'http://openclassroom.stanford.edu/MainFolder/' + unescapeHTML(cpage),
112                 }
113                     for cpage in links]
114
115             results = []
116             for entry in info['list']:
117                 assert entry['type'] == 'reference'
118                 results += self.extract(entry['url'])
119             return results