Add `open_piker_runtime()` to setup actor runtime correctly from non-daemons

piker/_daemon.py

@@ -34,9 +34,11 @@ from .brokers import get_brokermod
 log = get_logger(__name__)
 
 _root_dname = 'pikerd'
+
+_registry_addr = ('127.0.0.1', 6116)
 _tractor_kwargs: dict[str, Any] = {
     # use a different registry addr then tractor's default
-    'arbiter_addr':  ('127.0.0.1', 6116),
+    'arbiter_addr':  _registry_addr
 }
 _root_modules = [
     __name__,
@@ -150,7 +152,7 @@ async def open_pikerd(
         tractor.open_root_actor(
 
             # passed through to ``open_root_actor``
-            arbiter_addr=_tractor_kwargs['arbiter_addr'],
+            arbiter_addr=_registry_addr,
             name=_root_dname,
             loglevel=loglevel,
             debug_mode=debug_mode,
@@ -179,6 +181,47 @@ async def open_pikerd(
             yield _services
 
 
+@asynccontextmanager
+async def open_piker_runtime(
+    name: str,
+    enable_modules: list[str] = [],
+    start_method: str = 'trio',
+    loglevel: Optional[str] = None,
+
+    # XXX: you should pretty much never want debug mode
+    # for data daemons when running in production.
+    debug_mode: bool = False,
+
+) -> Optional[tractor._portal.Portal]:
+    '''
+    Start a piker actor who's runtime will automatically
+    sync with existing piker actors in local network
+    based on configuration.
+
+    '''
+    global _services
+    assert _services is None
+
+    # XXX: this may open a root actor as well
+    async with (
+        tractor.open_root_actor(
+
+            # passed through to ``open_root_actor``
+            arbiter_addr=_registry_addr,
+            name=name,
+            loglevel=loglevel,
+            debug_mode=debug_mode,
+            start_method=start_method,
+
+            # TODO: eventually we should be able to avoid
+            # having the root have more then permissions to
+            # spawn other specialized daemons I think?
+            enable_modules=_root_modules,
+        ) as _,
+    ):
+        yield tractor.current_actor()
+
+
 @asynccontextmanager
 async def maybe_open_runtime(
     loglevel: Optional[str] = None,
@@ -283,13 +326,20 @@ async def maybe_spawn_daemon(
     lock = Brokerd.locks[service_name]
     await lock.acquire()
 
+    log.info(f'Scanning for existing {service_name}')
     # attach to existing daemon by name if possible
-    async with tractor.find_actor(service_name) as portal:
+    async with tractor.find_actor(
+        service_name,
+        arbiter_sockaddr=_registry_addr,
+
+    ) as portal:
         if portal is not None:
             lock.release()
             yield portal
             return
 
+        log.warning(f"Couldn't find any existing {service_name}")
+
     # ask root ``pikerd`` daemon to spawn the daemon we need if
     # pikerd is not live we now become the root of the
     # process tree