Reduce redundancy, and fix wrong var passed

src/arcaflow_plugin_sdk/atp.py

@@ -174,7 +174,7 @@ def run_server_read_loop(
                                      f"does not match expected step ID '{step_id}'")
                         return
                     unserialized_data = plugin_schema.unserialize_signal_handler_input(
-                        step_id,
+                        received_step_id,
                         received_signal_id,
                         signal_msg["data"]
                     )

src/arcaflow_plugin_sdk/schema.py

@@ -5681,6 +5681,17 @@ class SchemaType(Schema):
 
     steps: Dict[str, StepType]
 
+    def get_step(self, step_id: str):
+        if step_id not in self.steps:
+            raise NoSuchStepException(step_id)
+        return self.steps[step_id]
+
+    def get_signal(self, step_id: str, signal_id: str):
+        step = self.get_step(step_id)
+        if signal_id not in step.signal_handlers:
+            raise NoSuchSignalException(step_id, signal_id)
+        return step.signal_handlers[signal_id]
+
     def unserialize_step_input(self, step_id: str, serialized_data: Any) -> Any:
         """
         This function unserializes the input from a raw data to data structures, such as dataclasses. This function is
@@ -5690,10 +5701,7 @@ def unserialize_step_input(self, step_id: str, serialized_data: Any) -> Any:
         :param serialized_data: The raw data to unserialize.
         :return: The unserialized data in the structure the step expects it.
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-        return self._unserialize_step_input(step, serialized_data)
+        return self._unserialize_step_input(self.get_step(step_id), serialized_data)
 
     @staticmethod
     def _unserialize_step_input(step: StepType, serialized_data: Any) -> Any:
@@ -5711,12 +5719,7 @@ def unserialize_signal_handler_input(self, step_id: str, signal_id: str, seriali
         :param serialized_data: The raw data to unserialize.
         :return: The unserialized data in the structure the step expects it.
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-        if signal_id not in step.signal_handlers:
-            raise NoSuchSignalException(step_id, signal_id)
-        return self._unserialize_signal_handler_input(step, serialized_data)
+        return self._unserialize_signal_handler_input(self.get_signal(step_id, signal_id), serialized_data)
 
     @staticmethod
     def _unserialize_signal_handler_input(signal: SignalHandlerType, data: Any) -> Any:
@@ -5735,10 +5738,7 @@ def call_step(self, step_id: str, input_param: Any) -> typing.Tuple[str, Any]:
         :param input_param: The unserialized data structure the step expects.
         :return: The ID of the output, and the data structure returned from the step.
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-        return self._call_step(step, input_param)
+        return self._call_step(self.get_step(step_id), input_param)
 
     def call_step_signal(self, step_id: str, signal_id: str, unserialized_input_param: Any):
         """
@@ -5749,13 +5749,8 @@ def call_step_signal(self, step_id: str, signal_id: str, unserialized_input_para
         :param unserialized_input_param: The unserialized data structure the step expects.
         :return: The ID of the output, and the data structure returned from the step.
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-
-        if signal_id not in step.signal_handlers:
-            raise NoSuchSignalException(step_id, signal_id)
-        signal = step.signal_handlers[signal_id]
+        step = self.get_step(step_id)
+        signal = self.get_signal(step_id, signal_id)
         return signal(step.initializedObjectData, unserialized_input_param)
 
     @staticmethod
@@ -5781,10 +5776,7 @@ def serialize_output(self, step_id: str, output_id: str, output_data: Any) -> An
         :param output_data: The data structure returned from the step.
         :return:
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-        return self._serialize_output(step, output_id, output_data)
+        return self._serialize_output(self.get_step(step_id), output_id, output_data)
 
     @staticmethod
     def _serialize_output(step, output_id: str, output_data: Any) -> Any:
@@ -5805,10 +5797,8 @@ def __call__(
         :param skip_serialization: skip result serialization to basic types
         :return: the result ID, and the resulting data in the structure matching the result ID
         """
-        if step_id not in self.steps:
-            raise NoSuchStepException(step_id)
-        step = self.steps[step_id]
-        input_param = self.unserialize_step_input(step, data)
+        step = self.get_step(step_id)
+        input_param = self._unserialize_step_input(step, data)
         output_id, output_data = self._call_step(
             step,
             input_param,