Merge pull request #287 from sartography/feature/workflow_data_exceptions

Workflow Data Exceptions were broken in the previous error refactor. …

Author: danfunk

SpiffWorkflow/bpmn/exceptions.py

@@ -1,16 +1,14 @@
-from SpiffWorkflow.exceptions import WorkflowException
+from SpiffWorkflow.exceptions import WorkflowTaskException
 
 
-class WorkflowDataException(WorkflowException):
+class WorkflowDataException(WorkflowTaskException):
 
-    def __init__(self, task, data_input=None, data_output=None, message=None):
+    def __init__(self, message, task, data_input=None, data_output=None):
         """
         :param task: the task that generated the error
         :param data_input: the spec of the input variable (if a data input)
         :param data_output: the spec of the output variable (if a data output)
         """
-        super().__init__(task.task_spec, message or 'data object error')
-        self.task = task
+        super().__init__(message, task)
         self.data_input = data_input
         self.data_output = data_output
-        self.task_trace = self.get_task_trace(task)

SpiffWorkflow/bpmn/specs/BpmnProcessSpec.py

@@ -72,28 +72,30 @@ def __init__(self, name, description=None):
     def get(self, my_task):
         """Copy a value form the workflow data to the task data."""
         if self.name not in my_task.workflow.data:
-            message = f"Workflow variable {self.name} not found"
-            raise WorkflowDataException(my_task, data_input=self, message=message)
+            message = f"Data object '{self.name}' " \
+                      f"does not exist and can not be read."
+            raise WorkflowDataException(message, my_task, data_input=self)
         my_task.data[self.name] = deepcopy(my_task.workflow.data[self.name])
 
     def set(self, my_task):
         """Copy a value from the task data to the workflow data"""
         if self.name not in my_task.data:
-            message = f"Task variable {self.name} not found"
-            raise WorkflowDataException(my_task, data_output=self, message=message)
+            message = f"A Data Object  '{self.name}' " \
+                      f"could not be set, it does not exist in the task data"
+            raise WorkflowDataException(message, my_task, data_output=self)
         my_task.workflow.data[self.name] = deepcopy(my_task.data[self.name])
         del my_task.data[self.name]
         data_log.info(f'Set workflow variable {self.name}', extra=my_task.log_info())
 
     def copy(self, source, destination, data_input=False, data_output=False):
         """Copy a value from one task to another."""
         if self.name not in source.data:
-            message = f"Unable to copy {self.name}"
+            message = f"'{self.name}' was not found in the task data"
             raise WorkflowDataException(
-                source, 
+                message,
+                source,
                 data_input=self if data_input else None,
                 data_output=self if data_output else None,
-                message=message
             )
         destination.data[self.name] = deepcopy(source.data[self.name])
 

SpiffWorkflow/bpmn/specs/SubWorkflowTask.py

@@ -3,6 +3,7 @@
 
 from SpiffWorkflow.task import TaskState
 from .BpmnSpecMixin import BpmnSpecMixin
+from ..exceptions import WorkflowDataException
 from ...specs.base import TaskSpec
 
 
@@ -51,7 +52,11 @@ def _on_subworkflow_completed(self, subworkflow, my_task):
             end = subworkflow.get_tasks_from_spec_name('End', workflow=subworkflow)
             # Otherwise only copy data with the specified names
             for var in subworkflow.spec.data_outputs:
-                var.copy(end[0], my_task, data_output=True)
+                try:
+                    var.copy(end[0], my_task, data_output=True)
+                except WorkflowDataException as wde:
+                    wde.add_note("A Data Output was not provided as promised.")
+                    raise wde
 
         my_task._set_state(TaskState.READY)
 
@@ -83,8 +88,11 @@ def start_workflow(self, my_task):
         else:
             # Otherwise copy only task data with the specified names
             for var in subworkflow.spec.data_inputs:
-                var.copy(my_task, start[0], data_input=True)
-
+                try:
+                    var.copy(my_task, start[0], data_input=True)
+                except WorkflowDataException as wde:
+                    wde.add_note("You are missing a required Data Input for a call activity.")
+                    raise wde
         for child in subworkflow.task_tree.children:
             child.task_spec._update(child)
 

tests/SpiffWorkflow/bpmn/IOSpecTest.py

@@ -18,14 +18,17 @@ def testCallActivityWithIOSpecSaveRestore(self):
         self.actual_test(True)
 
     def testCallActivityMissingInput(self):
-        
+
         self.workflow = BpmnWorkflow(self.spec, self.subprocesses)
         set_data = self.workflow.spec.task_specs['Activity_0haob58']
         set_data.script = """in_1, unused = 1, True"""
 
         with self.assertRaises(WorkflowDataException) as exc:
             self.advance_to_subprocess()
-            self.assertEqual(exc.var.name,'in_2')
+        self.assertEqual("'in_2' was not found in the task data. "
+                         "You are missing a required Data Input for a call activity.",
+                         str(exc.exception))
+        self.assertEqual(exc.exception.data_input.name,'in_2')
 
     def testCallActivityMissingOutput(self):
 
@@ -40,7 +43,10 @@ def testCallActivityMissingOutput(self):
 
         with self.assertRaises(WorkflowDataException) as exc:
             self.complete_subprocess()
-            self.assertEqual(exc.var.name,'out_2')
+
+        self.assertEqual("'out_2' was not found in the task data. A Data Output was not provided as promised.",
+                         str(exc.exception))
+        self.assertEqual(exc.exception.data_output.name,'out_2')
 
     def actual_test(self, save_restore=False):
 
@@ -85,4 +91,4 @@ def complete_subprocess(self):
         while len(waiting) > 0:
             next_task = self.workflow.get_tasks(TaskState.READY)[0]
             next_task.complete()
-            waiting = self.workflow.get_tasks(TaskState.WAITING)
+            waiting = self.workflow.get_tasks(TaskState.WAITING)