Fix backend execution import error and Airflow callback typing

backend/api/routes/executions.py

@@ -73,25 +73,6 @@ def initialize_execution(pipeline_id: str, context: Optional[Dict[str, Any]] = N
     return execution
 
 
-def initialize_execution(pipeline_id: str, context: Optional[Dict[str, Any]] = None) -> Execution:
-def initialize_execution(pipeline_id: str, context: Dict = None) -> Execution:
-    """Create and store a pending execution record."""
-    from datetime import datetime
-
-    execution_id = f"exec-{uuid.uuid4()}"
-    pipeline = pipelines_db[pipeline_id]
-    execution = Execution(
-        id=execution_id,
-        pipeline_id=pipeline_id,
-        status=ExecutionStatus.PENDING,
-        started_at=datetime.now(),
-        total_stages=len(pipeline.stages),
-        context=context or {}
-    )
-    executions_db[execution_id] = execution
-    return execution
-
-
 async def execute_pipeline_background(pipeline_id: str, execution_id: str):
     """Background task to execute pipeline."""
     try:
@@ -115,11 +96,6 @@ async def execute_pipeline_background(pipeline_id: str, execution_id: str):
                 result.error = existing.error
 
         result.id = execution_id
-        if execution_id in executions_db:
-            existing_context = executions_db[execution_id].context.copy()
-            result.context.update(existing_context)
-
-        result.id = execution_id  # Use the pre-assigned ID
         executions_db[execution_id] = result
     except Exception as e:
         if execution_id in executions_db:

backend/api/schemas.py

@@ -118,7 +118,6 @@ class AirflowCallbackRequest(BaseModel):
     """Schema for processing Airflow run callbacks."""
     execution_id: str
     callback_type: AirflowCallbackTypeSchema
-    callback_type: str = Field(description="success, failure, retry, running, cancelled")
     dag_id: str
     dag_run_id: str
     task_id: Optional[str] = None