def gather_constructors(service_methods, construct):
"""Loads the construct methods that are defined."""
try:
_methods = service_methods
except KeyError:
pass
else:
for meth in _methods:
try:
func = meth['function']
except KeyError:
pass
else:
construct.append(util.importer(func))
def init_services(service_definitions,
service_context,
state_db,
client_authn_factory=None):
"""
Initiates a set of services
:param service_definitions: A dictionary containing service definitions
:param service_context: A reference to the service context, this is the same
for all service instances.
:param state_db: A reference to the state database. Shared by all the
services.
:param client_authn_factory: A list of methods the services can use to
authenticate the client to a service.
:return: A dictionary, with service name as key and the service instance as
value.
"""
service = {}
for service_name, service_configuration in service_definitions.items():
try:
kwargs = service_configuration['kwargs']
except KeyError:
kwargs = {}
kwargs.update({
'service_context': service_context,
'state_db': state_db,
'client_authn_factory': client_authn_factory
})
if isinstance(service_configuration['class'], str):
_srv = util.importer(service_configuration['class'])(**kwargs)
else:
_srv = service_configuration['class'](**kwargs)
if 'post_functions' in service_configuration:
gather_constructors(service_configuration['post_functions'],
_srv.post_construct)
if 'pre_functions' in service_configuration:
gather_constructors(service_configuration['pre_functions'],
_srv.pre_construct)
try:
service[_srv.service_name] = _srv
except AttributeError:
raise ValueError("Could not load '{}'".format(service_name))
return service
def do_add_ons(add_ons, services):
for key, spec in add_ons.items():
_func = importer(spec['function'])
_func(services, **spec['kwargs'])
