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ServiceBase

What it is​

  • A small base class for services that need access to an engine-provided Services container.
  • Supports “wiring” dependencies after instantiation and provides a guard to ensure wiring happened.

Public API​

  • class ServiceBase
    • __init__(self) -> None
      • Initializes the service with no wired services (_services = None).
    • set_services(self, services: IEngine.Services) -> None
      • Wires an IEngine.Services container into the service.
    • services_wired(self) -> bool (property)
      • Returns True if services have been wired; otherwise False.
    • services(self) -> IEngine.Services (property)
      • Returns the wired services container.
      • Raises an AssertionError if services are not wired.

Configuration/Dependencies​

  • Type dependency (for typing only): naas_abi_core.engine.IEngine.IEngine, specifically IEngine.Services.
  • No runtime imports from IEngine due to TYPE_CHECKING.

Usage​

from naas_abi_core.services.ServiceBase import ServiceBase

class MyService(ServiceBase):
    def do_something(self):
        # Access wired services
        return self.services  # replace with actual service usage

svc = MyService()
assert not svc.services_wired

# Later: wire dependencies (engine would typically do this)
services_container = object()  # placeholder for IEngine.Services
svc.set_services(services_container)

assert svc.services_wired
_ = svc.services

Caveats​

  • Accessing services before calling set_services(...) triggers:
    • AssertionError: Services are not wired.