heron/statemgrs/src/python/statemanagerfactory.py

#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

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'''
statemanagerfactory.py
Factory function that instantiates and connects to the requested
state managers based on a conf file.
Returns these state managers.
'''

import os


from heron.statemgrs.src.python.filestatemanager import FileStateManager
from heron.statemgrs.src.python.log import Log as LOG
from heron.statemgrs.src.python.zkstatemanager import ZkStateManager

def get_all_state_managers(conf):
  """
  @param conf - An instance of Config class
  Reads the config for requested state managers.
  Instantiates them, start and then return them.
  """
  state_managers = []
  try:
    state_managers.extend(get_all_zk_state_managers(conf))
    state_managers.extend(get_all_file_state_managers(conf))
    return state_managers
  except Exception as ex:
    LOG.error("Exception while getting state_managers.")
    raise ex

def get_all_zk_state_managers(conf):
  """
  Creates all the zookeeper state_managers and returns
  them in a list
  """
  state_managers = []
  state_locations = conf.get_state_locations_of_type("zookeeper")
  for location in state_locations:
    name = location['name']
    hostport = location['hostport']
    hostportlist = []
    for hostportpair in hostport.split(','):
      host = None
      port = None
      if ':' in hostport:
        hostandport = hostportpair.split(':')
        if len(hostandport) == 2:
          host = hostandport[0]
          port = int(hostandport[1])
      if not host or not port:
        raise Exception("Hostport for %s must be of the format 'host:port'." % (name))
      hostportlist.append((host, port))
    tunnelhost = location['tunnelhost']
    rootpath = location['rootpath']
    LOG.info("Connecting to zk hostports: " + str(hostportlist) + " rootpath: " + rootpath)
    state_manager = ZkStateManager(name, hostportlist, rootpath, tunnelhost)
    state_managers.append(state_manager)

  return state_managers

def get_all_file_state_managers(conf):
  """
  Returns all the file state_managers.
  """
  state_managers = []
  state_locations = conf.get_state_locations_of_type("file")
  for location in state_locations:
    name = location['name']
    rootpath = os.path.expanduser(location['rootpath'])
    LOG.info("Connecting to file state with rootpath: " + rootpath)
    state_manager = FileStateManager(name, rootpath)
    state_managers.append(state_manager)

  return state_managers