+ _FEDERATED_URL_TEMPLATE = 'http://c.brightcove.com/services/viewer/htmlFederated?%s'
+
+ # There is a test for Brigtcove in GenericIE, that way we test both the download
+ # and the detection of videos, and we don't have to find an URL that is always valid
+
+ @classmethod
+ def _build_brighcove_url(cls, object_str):
+ """
+ Build a Brightcove url from a xml string containing
+ <object class="BrightcoveExperience">{params}</object>
+ """
+ object_doc = xml.etree.ElementTree.fromstring(object_str)
+ assert object_doc.attrib['class'] == u'BrightcoveExperience'
+ params = {'flashID': object_doc.attrib['id'],
+ 'playerID': object_doc.find('./param[@name="playerID"]').attrib['value'],
+ '@videoPlayer': object_doc.find('./param[@name="@videoPlayer"]').attrib['value'],
+ }
+ playerKey = object_doc.find('./param[@name="playerKey"]')
+ # Not all pages define this value
+ if playerKey is not None:
+ params['playerKey'] = playerKey.attrib['value']
+ data = compat_urllib_parse.urlencode(params)
+ return cls._FEDERATED_URL_TEMPLATE % data