def __init__(self, dbobj, logger, required_only=False):
"""Initialize the chooser.
To clear out bindings that are not required, pass in
required_only=True.
Several staging areas and caches are set up within this object.
The general flow is that potential service instance choices
are kept in staging_services (dictionary of service to list of
service instances) and finalized into chosen_services (dictionary
of service to single service instance).
The original state of the object is held in the cache
original_service_instances (dictionary of service to single service
instance).
The instances_bound and instances_unbound lists are populated
after chosen_services with the differences between chosen_services
and original_service_instances.
Subclasses should call this before starting their own
initialization.
"""
self.dbobj = dbobj
self.session = object_session(dbobj)
self.required_only = required_only
self.logger = logger
self.description = self.generate_description()
self.logger.debug("Creating service Chooser for %s", self.description)
# Cache of the service maps
self.mapped_services = {}
# Stores interim service instance lists
self.staging_services = {}
# Report as many errors as possible in one shot
self.errors = []
# Cache the servers backing service instances
self.servers = {}
# Set of service instances with a new client
self.instances_bound = set()
# Set of service instances losing a client
self.instances_unbound = set()
# Track the chosen services
self.chosen_services = {}
# Keep stashed plenaries for rollback purposes
self.plenaries = PlenaryCollection(logger=self.logger)
legacy_env = HostEnvironment.get_unique(session,
'legacy',
compel=True)
if dbpersona.host_environment == legacy_env:
HostEnvironment.polymorphic_subclass(
host_environment, "Unknown environment name")
Personality.validate_env_in_name(personality, host_environment)
dbpersona.host_environment = HostEnvironment.get_unique(
session, host_environment, compel=True)
else:
raise ArgumentError(
"The personality '{0}' already has env set to '{1}'"
" and cannot be updated".format(str(dbpersona),
host_environment))
plenaries = PlenaryCollection(logger=logger)
if grn or eon_id:
dbgrn = lookup_grn(session,
grn,
eon_id,
logger=logger,
config=self.config)
old_grn = dbpersona.owner_grn
dbpersona.owner_grn = dbgrn
if not leave_existing:
# If this is a public personality, then there may be hosts with
# various GRNs inside the personality, so make sure we preserve
# those GRNs by filtering on the original GRN of the personality
q = session.query(Host)
