[ustream] Simplify channel extraction

the ChannelParser has been moved to a new function in utils get_meta_content
Instead of the SocialStreamParser now it uses a regex

2 files changed, 49 insertions, 52 deletions

diff --git a/youtube_dl/extractor/ustream.py b/youtube_dl/extractor/ustream.py
index f69b27d44..74c82587f 100644
--- a/youtube_dl/extractor/ustream.py
+++ b/youtube_dl/extractor/ustream.py
@@ -4,7 +4,7 @@ import re
 from .common import InfoExtractor
 from ..utils import (
     compat_urlparse,
-    compat_html_parser,
+    get_meta_content,
 )
 
 
@@ -49,40 +49,6 @@ class UstreamIE(InfoExtractor):
                }
         return info
 
-# More robust than regular expressions
-
-class ChannelParser(compat_html_parser.HTMLParser):
-    """
-    <meta name="ustream:channel_id" content="1234">
-    """
-    channel_id = None
-
-    def handle_starttag(self, tag, attrs):
-        if tag != 'meta':
-            return
-        values = dict(attrs)
-        if values.get('name') != 'ustream:channel_id':
-            return
-        value = values.get('content', '')
-        if value.isdigit():
-            self.channel_id = value
-
-class SocialstreamParser(compat_html_parser.HTMLParser):
-    """
-    <li class="content123 video" data-content-id="123" data-length="1452"
-        data-href="/recorded/123" data-og-url="/recorded/123">
-    """
-    def __init__(self):
-        compat_html_parser.HTMLParser.__init__(self)
-        self.content_ids = []
-
-    def handle_starttag(self, tag, attrs):
-        if tag != 'li':
-            return
-        for (attr, value) in attrs:
-            if attr == 'data-content-id' and value.isdigit():
-                self.content_ids.append(value)
-
 class UstreamChannelIE(InfoExtractor):
     _VALID_URL = r'https?://www\.ustream\.tv/channel/(?P<slug>.+)'
     IE_NAME = u'ustream:channel'
@@ -90,21 +56,16 @@ class UstreamChannelIE(InfoExtractor):
     def _real_extract(self, url):
         m = re.match(self._VALID_URL, url)
         slug = m.group('slug')
+        webpage = self._download_webpage(url, slug)
+        channel_id = get_meta_content('ustream:channel_id', webpage)
 
-        p = ChannelParser()
-        p.feed(self._download_webpage(url, slug))
-        p.close()
-        channel_id = p.channel_id
-
-        p = SocialstreamParser()
         BASE = 'http://www.ustream.tv'
         next_url = '/ajax/socialstream/videos/%s/1.json' % channel_id
+        video_ids = []
         while next_url:
             reply = json.loads(self._download_webpage(compat_urlparse.urljoin(BASE, next_url), channel_id))
-            p.feed(reply['data'])
+            video_ids.extend(re.findall(r'data-content-id="(\d.*)"', reply['data']))
             next_url = reply['nextUrl']
-        p.close()
-        video_ids = p.content_ids
 
         urls = ['http://www.ustream.tv/recorded/' + vid for vid in video_ids]
         url_entries = [self.url_result(eurl, 'Ustream') for eurl in urls]
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index 201802cee..768c6207d 100644
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -249,7 +249,17 @@ def htmlentity_transform(matchobj):
     return (u'&%s;' % entity)
 
 compat_html_parser.locatestarttagend = re.compile(r"""<[a-zA-Z][-.a-zA-Z0-9:_]*(?:\s+(?:(?<=['"\s])[^\s/>][^\s/=>]*(?:\s*=+\s*(?:'[^']*'|"[^"]*"|(?!['"])[^>\s]*))?\s*)*)?\s*""", re.VERBOSE) # backport bugfix
-class AttrParser(compat_html_parser.HTMLParser):
+class BaseHTMLParser(compat_html_parser.HTMLParser):
+    def __init(self):
+        compat_html_parser.HTMLParser.__init__(self)
+        self.html = None
+
+    def loads(self, html):
+        self.html = html
+        self.feed(html)
+        self.close()
+
+class AttrParser(BaseHTMLParser):
     """Modified HTMLParser that isolates a tag with the specified attribute"""
     def __init__(self, attribute, value):
         self.attribute = attribute
@@ -257,10 +267,9 @@ class AttrParser(compat_html_parser.HTMLParser):
         self.result = None
         self.started = False
         self.depth = {}
-        self.html = None
         self.watch_startpos = False
         self.error_count = 0
-        compat_html_parser.HTMLParser.__init__(self)
+        BaseHTMLParser.__init__(self)
 
     def error(self, message):
         if self.error_count > 10 or self.started:
@@ -269,11 +278,6 @@ class AttrParser(compat_html_parser.HTMLParser):
         self.error_count += 1
         self.goahead(1)
 
-    def loads(self, html):
-        self.html = html
-        self.feed(html)
-        self.close()
-
     def handle_starttag(self, tag, attrs):
         attrs = dict(attrs)
         if self.started:
@@ -334,6 +338,38 @@ def get_element_by_attribute(attribute, value, html):
         pass
     return parser.get_result()
 
+class MetaParser(BaseHTMLParser):
+    """
+    Modified HTMLParser that isolates a meta tag with the specified name 
+    attribute.
+    """
+    def __init__(self, name):
+        BaseHTMLParser.__init__(self)
+        self.name = name
+        self.content = None
+        self.result = None
+
+    def handle_starttag(self, tag, attrs):
+        if tag != 'meta':
+            return
+        attrs = dict(attrs)
+        if attrs.get('name') == self.name:
+            self.result = attrs.get('content')
+
+    def get_result(self):
+        return self.result
+
+def get_meta_content(name, html):
+    """
+    Return the content attribute from the meta tag with the given name attribute.
+    """
+    parser = MetaParser(name)
+    try:
+        parser.loads(html)
+    except compat_html_parser.HTMLParseError:
+        pass
+    return parser.get_result()
+
 
 def clean_html(html):
     """Clean an HTML snippet into a readable string"""