Exceptions: added StateTransitionFailed and Maintenance Exceptions. ALso BECCommunicationException

src/aare/common/exception_handler.py

@@ -17,6 +17,26 @@ class TransformationInvalidException(Exception):
         return self.message
 
 
+class StateTransitionFailed(Exception):
+    def __init__(self, message: str = "Beamline state transition failed"):
+        super().__init__(message)
+        self.message = message
+        logger.error(message, extra={"exception:": Exception})
+
+    def __str__(self) -> str:
+        return self.message
+
+
+class MaintenanceStateException(Exception):
+    def __init__(self, message: str = "Beamline is in Maintenance state"):
+        super().__init__(message)
+        self.message = message
+        logger.error(message, extra={"exception:": Exception})
+
+    def __str__(self) -> str:
+        return self.message
+
+
 class DataCollectionException(Exception):
     def __init__(self, message: str = "Data collection failed"):
         super().__init__(message)
@@ -409,4 +429,33 @@ class MagnetPositionSensorErorr(Exception):
         )
 
     def __str__(self) -> str:
-        return self.message
+        return self.message
+
+class BECCommunicationError(Exception):
+    def __init__(
+            self,
+            message: str = "BEC communication error",
+            *,
+            exception: Exception | None = None,
+            operation: str | None = None,
+            endpoint: str | None = None,
+            base_url: str | None = None,
+            ):
+        self.message = message
+        self.operation = operation
+        self.exception = exception
+        self.endpoint = endpoint
+        self.base_url = base_url
+        logger.error(
+            message,
+            extra={
+                "device": "bec",
+                "operation": operation,
+                "endpoint": endpoint,
+                "base_url": base_url,
+                "exception": exception,
+                },
+        )
+
+    def __str__(self) -> str:
+        return self.message

src/aare/daq/server_exception_handler.py

@@ -13,12 +13,15 @@ from aare.common.exception_handler import (
     CriticalTellException,
     LoopCenteringFailed,
     TransformationInvalidException,
+    StateTransitionFailed,
+    MaintenanceStateException,
     BeamlineBusyException,
     AuthenticationException,
     SampleException,
     UserRightsException,
     SmargonCommunicationError,
     TellCommunicationError,
+    BECCommunicationError,
     JFJochCommunicationError,
     AerotechCommunicationError,
     DataCollectionException,
@@ -237,6 +240,22 @@ def register_exception_handlers(app) -> None:
             ),
         )
 
+    @app.exception_handler(BECCommunicationError)
+    async def bec_comm_handler(request: Request, exc: BECCommunicationError) -> JSONResponse:
+        return JSONResponse(
+            status_code=api_status.HTTP_503_SERVICE_UNAVAILABLE,
+            content=_error_payload(
+                code="BEC_UNAVAILABLE",
+                message=str(exc) or "BEC is unavailable",
+                extra={
+                    "operation": getattr(exc, "operation", None),
+                    "endpoint": getattr(exc, "endpoint", None),
+                    "base_url": getattr(exc, "base_url", None),
+                },
+            ),
+        )
+
+
     @app.exception_handler(JFJochCommunicationError)
     async def jfjoch_comm_handler(request: Request, exc: JFJochCommunicationError) -> JSONResponse:
         return JSONResponse(