DetectorAssembler: go to ERROR if trying to match without geometry

#48 (closed) this came up again recently, let's do something about it.

• geometry is a property again, so if geometry device is up, we don't even need to wait for signal to get it
• DRY a bit by putting utility to get property + connect to signal in calngUtils
• start warning harder if no geometry

Options:

1. stay in INIT until we get geometry
2. go to ERROR after some timeout if we don't get geometry
3. go to ERROR in match handler if we don't have geometry by the time we need it (current implementation)

As the diff shows, at least for option 3, we need to fight the TrainMatcher state logic a bit; it's going from PASSIVE to CHANGING to ACTIVE outside of the methods we're currently overriding. State transitions for an assembler started while geometry device is down and then geometry device comes up later:

src/calng/FrameSelectionArbiter.py

@@ -2,7 +2,7 @@ import enum
 from importlib.metadata import entry_points
 
 import numpy as np
-from geometryDevices import utils as geom_utils
+from calngUtils import geom_utils
 from karabo.bound import (
     BOOL_ELEMENT,
     KARABO_CLASSINFO,
@@ -136,7 +136,6 @@ class BaseFrameSelectionArbiter(TrainMatcher.TrainMatcher):
 
     def __init__(self, config):
         super().__init__(config)
-        self.registerSlot(self.slotReceiveGeometry)
 
     def initialization(self):
         super().initialization()
@@ -145,13 +144,6 @@ class BaseFrameSelectionArbiter(TrainMatcher.TrainMatcher):
         )
 
         self._geometry = None
-        if self.get("geometryDevice"):
-            self.signalSlotable.connect(
-                self.get("geometryDevice"),
-                "signalNewGeometry",
-                "",  # slot device ID (default: self)
-                "slotReceiveGeometry",
-            )
 
     def _guess_number_of_frames(self, sources):
         # TODO: robust frame deduction
@@ -160,12 +152,6 @@ class BaseFrameSelectionArbiter(TrainMatcher.TrainMatcher):
                 return data.get("image.cellId").size
         self.log.ERROR("Unable to figure out number of frames")
 
-    def slotReceiveGeometry(self, device_id, serialized_geometry):
-        self.log.INFO(f"Received geometry from {device_id}")
-        try:
-            self._geometry = geom_utils.deserialize_geometry(serialized_geometry)
-        except Exception as e:
-            self.log.WARN(f"Failed to deserialize geometry; {e}")
 
 @KARABO_CLASSINFO("SimpleFrameSelectionArbiter", deviceVersion)
 class SimpleFrameSelectionArbiter(BaseFrameSelectionArbiter):
@@ -195,6 +181,9 @@ class SimpleFrameSelectionArbiter(BaseFrameSelectionArbiter):
         self._initialize_kernel(
             self["frameSelection.kernelChoice"], self["frameSelection.kernelParameters"]
         )
+        geom_utils.subscribe_to_geometry_bound(
+            self, self.get("geometryDevice"), on_geometry=self._on_geometry
+        )
 
         if self["state"] != State.ERROR:
             self.start()  # Auto-start this type of matcher.
@@ -270,6 +259,9 @@ class SimpleFrameSelectionArbiter(BaseFrameSelectionArbiter):
         self.info["trainId"] = train_id
         self.rate_out.update()
 
+    def _on_geometry(self, geometry):
+        self.kernel.on_new_geometry(geometry)
+
 
 @KARABO_CLASSINFO("AdvancedFrameSelectionArbiter", deviceVersion)
 class AdvancedFrameSelectionArbiter(BaseFrameSelectionArbiter):
@@ -315,6 +307,9 @@ class AdvancedFrameSelectionArbiter(BaseFrameSelectionArbiter):
         self._validate_plan_and_update_schema(self["frameSelection.plan"])
         self._initialize_kernels()
         self._configure_decision(self["frameSelection.decision"])
+        geom_utils.subscribe_to_geometry_bound(
+            self, self.get("geometryDevice"), on_geometry=self._on_geometry
+        )
 
         if self["state"] != State.ERROR:
             self.start()  # Auto-start this type of matcher.
@@ -523,3 +518,7 @@ class AdvancedFrameSelectionArbiter(BaseFrameSelectionArbiter):
                 kernel_prefix = f"frameSelection.selections.{name}"
                 if conf.has(kernel_prefix):
                     kernel.reconfigure(conf[kernel_prefix])
+
+    def _on_geometry(self, geometry):
+        for kernel in self._selection_kernels.values():
+            kernel.on_new_geometry(geometry)