def feed_validate():
"""preview a feed"""
feed_type = int(request.form.get('feed_type', 1))
form = FEED_TYPE_TO_CLASS[feed_type].preview_form(request.form)
if not form.validate():
raise ndb.Return(jsonify(status='error', form_errors=form.errors))
feed = Feed()
form.populate_obj(feed)
feed.preview = True
error = None
try:
parsed_feed, resp = yield fetch_parsed_feed_for_feed(feed)
feed.update_feed_from_parsed_feed(parsed_feed)
except FetchException, e:
error = unicode(e)
