text: ##############################################################################
  # Copyright 2018 Parker Berberian and Others                                 #
  #                                                                            #
  # Licensed under the Apache License, Version 2.0 (the "License");            #
  # you may not use this file except in compliance with the License.           #
  # You may obtain a copy of the License at                                    #
  #                                                                            #
  #    http://www.apache.org/licenses/LICENSE-2.0                              #
  #                                                                            #
  # Unless required by applicable law or agreed to in writing, software        #
  # distributed under the License is distributed on an "AS IS" BASIS,          #
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   #
  # See the License for the specific language governing permissions and        #
  # limitations under the License.                                             #
  ##############################################################################
  
  from st2actions.runners.pythonrunner import Action
  import json
  import requests
  
  
  class DetectHostsAction(Action):
      def __init__(self, *args, **kwargs):
          self._config = kwargs.get('config', None)
          super(DetectHostsAction, self).__init__(*args, **kwargs)
  
          server = self._config['dashboard']['address']
          name = self._config['dashboard']['lab_name']
          auth = self.action_service.get_value("lab_auth_token", local=False)
  
          self.base_url = server + "/api/labs/" + name + "/hosts/"
          self.header = {"auth-token": auth}
  
      def run(self):
          hosts_to_boot = set()
          my_hosts = json.loads(
              self.action_service.get_value(name="hosts", local=False)
          )
          for host in my_hosts:
              if self.is_booked(host):
                  hosts_to_boot.add(host)
          self.action_service.set_value(name="hosts_to_boot", value=json.dumps(list(hosts_to_boot)), local=False)
  
      def is_booked(self, hostname):
          url = self.base_url + hostname
  
          try:
              response = requests.get(url, timeout=10, headers=self.header)
              return response.json()['booked']
          except:
              self.logger.exception("Something happened..")
              return True  # return true on failure to be safe
  