Allow TOs to be deleted, along with their associated CLINs

atst/domain/task_orders.py

@@ -71,3 +71,10 @@ class TaskOrders(BaseDomainClass):
         by_time_created = sorted(task_orders, key=lambda to: to.time_created)
         by_status = sorted(by_time_created, key=lambda to: SORT_ORDERING.get(to.status))
         return by_status
+
+    @classmethod
+    def delete(cls, task_order_id):
+        task_order = TaskOrders.get(task_order_id)
+        if task_order:
+            db.session.delete(task_order)
+            db.session.commit()

atst/models/task_order.py

@@ -44,7 +44,9 @@ class TaskOrder(Base, mixins.TimestampsMixin):
     signer_dod_id = Column(String)
     signed_at = Column(DateTime)
 
-    clins = relationship("CLIN", back_populates="task_order")
+    clins = relationship(
+        "CLIN", back_populates="task_order", cascade="all, delete-orphan"
+    )
 
     @hybrid_property
     def pdf(self):