[utils] Relax attribute key assert

[youtube-dl] / youtube_dl / utils.py

diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index b7a423166997766d8903b5697dc764008978bc6b..86b75710300251379cca9b31cacaecc5cb43c6ed 100644 (file)
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -141,7 +141,7 @@ def write_json_file(obj, fn):
 if sys.version_info >= (2, 7):
     def find_xpath_attr(node, xpath, key, val=None):
         """ Find the xpath xpath[@key=val] """
-        assert re.match(r'^[a-zA-Z-]+$', key)
+        assert re.match(r'^[a-zA-Z_-]+$', key)
         if val:
             assert re.match(r'^[a-zA-Z0-9@\s:._-]*$', val)
         expr = xpath + ('[@%s]' % key if val is None else "[@%s='%s']" % (key, val))
@@ -176,7 +176,7 @@ def xpath_with_ns(path, ns_map):
     return '/'.join(replaced)
 
 
-def xpath_text(node, xpath, name=None, fatal=False, default=NO_DEFAULT):
+def xpath_element(node, xpath, name=None, fatal=False, default=NO_DEFAULT):
     if sys.version_info < (2, 7):  # Crazy 2.6
         xpath = xpath.encode('ascii')
 
@@ -189,7 +189,24 @@ def xpath_text(node, xpath, name=None, fatal=False, default=NO_DEFAULT):
             raise ExtractorError('Could not find XML element %s' % name)
         else:
             return None
-    return n.text
+    return n
+
+
+def xpath_text(node, xpath, name=None, fatal=False, default=NO_DEFAULT):
+    return xpath_element(node, xpath, name, fatal=fatal, default=default).text
+
+
+def xpath_attr(node, xpath, key, name=None, fatal=False, default=NO_DEFAULT):
+    n = find_xpath_attr(node, xpath, key)
+    if n is None:
+        if default is not NO_DEFAULT:
+            return default
+        elif fatal:
+            name = '%s[@%s]' % (xpath, key) if name is None else name
+            raise ExtractorError('Could not find XML attribute %s' % name)
+        else:
+            return None
+    return n.attrib[key]
 
 
 def get_element_by_id(id, html):