def _any_response(self, params):
"""Generate a response to ANY/A query.
See polaris_health.state to_dist_dict() methods for the distribution
state implementation details.
"""
qname = params['qname'].lower()
# get a pool associated with the qname
pool_name = STATE['globalnames'][qname]['pool_name']
pool = STATE['pools'][pool_name]
# use the _default distribution table by default
dist_table = pool['dist_tables']['_default']
# pool is UP
if pool['status']:
# if using a topology based method, check if we have a distribution
# table in the same region, if so - use it
if pool['lb_method'] == 'twrr':
# we'll log the time it takes to perfom a topology lookup
t = time.time()
# lookup the client's region, get_region() will
# return None if the region cannot be determined
region = topology.get_region(params['remote'],
config.TOPOLOGY_MAP)
# log the time taken to perform the lookup
self.log.append(
'get_region() time taken: {:.6f}'.format(time.time() - t))
# log client's region
self.log.append('client region: {}'.format(region))
# if we have a region table corresponding
# to the client's region - use it
if region in pool['dist_tables']:
dist_table = pool['dist_tables'][region]
# pool is DOWN
else:
# if fallback is set to "refuse", refuse the query
# (SOA response must return False as well)
if pool['fallback'] == 'refuse':
self.result = False
return
# otherwise(fallback is "any") use the _default distribution table
# log the distribution table used
self.log.append('dist table used: {}'.format(json.dumps(dist_table)))
# determine how many records to return
# which is the minimum of the dist table's num_unique_addrs and
# the pool's max_addrs_returned
if dist_table['num_unique_addrs'] <= pool['max_addrs_returned']:
num_records_return = dist_table['num_unique_addrs']
else:
num_records_return = pool['max_addrs_returned']
# if we don't have anything to return(all member weights may have
# been set of 0), set the result to false
if num_records_return == 0:
self.result = False
return
# add records to the response
for i in range(num_records_return):
# add record to the response
self.add_record(
qtype='A',
# use the original qname from the parameters dict
qname=params['qname'],
content=dist_table['rotation'][dist_table['index']],
ttl=STATE['globalnames'][qname]['ttl'])
# increase index
dist_table['index'] += 1
# set the index to 0 if we reached the end of the rotation list
if dist_table['index'] >= len(dist_table['rotation']):
dist_table['index'] = 0
def _any_response(self, params):
"""Generate a response to ANY/A query.
See polaris_health.state to_dist_dict() methods for the distribution
state implementation details.
"""
qname = params['qname'].lower()
# get a pool associated with the qname
pool_name = self._state['globalnames'][qname]['pool_name']
pool = self._state['pools'][pool_name]
# use the _default distribution table by default
dist_table = pool['dist_tables']['_default']
##################
### pool is UP ###
##################
if pool['status']:
# if using a topology based method, check if we have a distribution
# table in the same region, if so - use it
if pool['lb_method'] == 'twrr':
# we'll log the time it takes to perfom a topology lookup
t = time.time()
# lookup the client's region, get_region() will
# return None if the region cannot be determined
region = topology.get_region(params['remote'],
config.TOPOLOGY_MAP)
# log the time taken to perform the lookup
self.log.append(
'get_region() time taken: {:.6f}'.format(time.time() - t))
# log client's region
self.log.append('client region: {}'.format(region))
# if we have a region table corresponding
# to the client's region - use it
if region in pool['dist_tables']:
dist_table = pool['dist_tables'][region]
####################
### pool is DOWN ###
####################
else:
# if fallback is set to "refuse", refuse the query
# (SOA response must return False as well)
if pool['fallback'] == 'refuse':
self.result = False
return
# otherwise(fallback is "any") use the _default distribution table
# log the distribution table used
self.log.append('dist table used: {}'
.format(json.dumps(dist_table)))
# determine how many records to return
# which is the minimum of the dist table's num_unique_addrs and
# the pool's max_addrs_returned
if dist_table['num_unique_addrs'] <= pool['max_addrs_returned']:
num_records_return = dist_table['num_unique_addrs']
else:
num_records_return = pool['max_addrs_returned']
# if we don't have anything to return(all member weights may have
# been set of 0), set the result to false
if num_records_return == 0:
self.result = False
return
### add records to the response ###
for i in range(num_records_return):
# add record to the response
self.add_record(qtype='A',
# use the original qname from the parameters dict
qname=params['qname'],
content=dist_table['rotation'][dist_table['index']],
ttl=self._state['globalnames'][qname]['ttl'])
# increase index
dist_table['index'] += 1
# set the index to 0 if we reached the end of the rotation list
if dist_table['index'] >= len(dist_table['rotation']):
dist_table['index'] = 0
def from_config_dict(cls, pool_name, obj):
"""Build a Pool object from a config dict
args:
pool_name: string, pool_name of the pool
obj: dict, config dict
"""
#################################
### pool mandatory parameters ###
#################################
### monitor
if obj['monitor'] not in monitors.registered:
log_msg = 'unknown monitor "{}"'.format(obj['monitor'])
LOG.error(log_msg)
raise Error(log_msg)
else:
monitor_name = obj['monitor']
if 'monitor_params' in obj:
if not obj['monitor_params']:
log_msg = 'monitor_params should not be empty'
LOG.error(log_msg)
raise Error(log_msg)
monitor_params = obj['monitor_params']
else:
monitor_params = {}
monitor = monitors.registered[monitor_name](**monitor_params)
### lb_method
lb_method = obj['lb_method']
### members
members = []
# validate "members" key is present and not empty
if not 'members' in obj or not obj['members']:
log_msg = ('configuration dictionary must contain '
'a non-empty "members" list')
LOG.error(log_msg)
raise Error(log_msg)
for member_obj in obj['members']:
# ensure a member with the same IP doesn't exist already
for _m in members:
if member_obj['ip'] == _m.ip:
log_msg = 'duplicate member IP {}'.format(member_obj['ip'])
LOG.error(log_msg)
raise Error(log_msg)
### member optional parameters ###
member_optional_params = {}
### region
# if topology lb method is used - set region
if lb_method == 'twrr':
region = topology.get_region(
member_obj['ip'], config.TOPOLOGY_MAP)
if not region:
log_msg = ('unable to determine region for member {}({})'
.format(member_obj['ip'], member_obj['name']))
LOG.error(log_msg)
raise Error(log_msg)
member_optional_params['region'] = region
### monitor_ip
if 'monitor_ip' in member_obj:
member_optional_params['monitor_ip'] = member_obj['monitor_ip']
_m = PoolMember(ip=member_obj['ip'],
name=member_obj['name'],
weight=member_obj['weight'],
**member_optional_params)
members.append(_m)
################################
### pool optional parameters ###
################################
pool_optional_params = {}
### fallback
if 'fallback' in obj:
pool_optional_params['fallback'] = obj['fallback']
### max_addrs_returned
if 'max_addrs_returned' in obj:
pool_optional_params['max_addrs_returned'] = \
obj['max_addrs_returned']
# return Pool object
return cls(name=pool_name,
monitor=monitor,
lb_method=lb_method,
members=members,
**pool_optional_params)
def from_config_dict(cls, pool_name, obj):
"""Build a Pool object from a config dict
args:
pool_name: string, pool_name of the pool
obj: dict, config dict
"""
############################
### mandatory parameters ###
############################
### monitor
if obj['monitor'] not in monitors.registered:
log_msg = 'unknown monitor "{}"'.format(obj['monitor'])
LOG.error(log_msg)
raise Error(log_msg)
else:
monitor_name = obj['monitor']
if 'monitor_params' in obj:
if not obj['monitor_params']:
log_msg = 'monitor_params should not be empty'
LOG.error(log_msg)
raise Error(log_msg)
monitor_params = obj['monitor_params']
else:
monitor_params = {}
monitor = monitors.registered[monitor_name](**monitor_params)
### lb_method
lb_method = obj['lb_method']
### members
members = []
# validate "members" key is present and not empty
if not 'members' in obj or not obj['members']:
log_msg = ('configuration dictionary must contain '
'a non-empty "members" list')
LOG.error(log_msg)
raise Error(log_msg)
for member_obj in obj['members']:
# ensure a member with the same IP doesn't exist already
for _m in members:
if member_obj['ip'] == _m.ip:
log_msg = 'duplicate member IP {}'.format(member_obj['ip'])
LOG.error(log_msg)
raise Error(log_msg)
region = None
# if topology lb method is used - set region on the pool member
if lb_method == 'twrr':
region = topology.get_region(
member_obj['ip'], config.TOPOLOGY_MAP)
if not region:
log_msg = ('unable to determine region for member {}({})'
.format(member_obj['ip'], member_obj['name']))
LOG.error(log_msg)
raise Error(log_msg)
_m = PoolMember(ip=member_obj['ip'],
name=member_obj['name'],
weight=member_obj['weight'],
region=region)
members.append(_m)
###########################
### optional parameters ###
###########################
pool_optional_params = {}
### fallback
if 'fallback' in obj:
pool_optional_params['fallback'] = obj['fallback']
### max_addrs_returned
if 'max_addrs_returned' in obj:
pool_optional_params['max_addrs_returned'] = \
obj['max_addrs_returned']
# return Pool object
return cls(name=pool_name,
monitor=monitor,
lb_method=lb_method,
members=members,
**pool_optional_params)
