def METHOD_NAME(self, matches):
    subject = 'ElastAlert: %s' % (self.rule['name'])
    # If the rule has a query_key, add that value plus timestamp to subject
    if 'query_key' in self.rule:
        qk = matches[0].get(self.rule['query_key'])
        if qk:
            subject += ' - %s' % (qk)
    return subject