Merge pull request #3461 from alphagov/be-more-robust-around-references-to-cancel

Be more robust in handling ambiguous references to cancel an alert

app/dao/broadcast_message_dao.py

@@ -26,6 +26,10 @@ def dao_get_broadcast_message_by_id_and_service_id(broadcast_message_id, service
 
 def dao_get_broadcast_message_by_references_and_service_id(references_to_original_broadcast, service_id):
     return BroadcastMessage.query.filter(
+        BroadcastMessage.status.in_((
+            BroadcastStatusType.PENDING_APPROVAL,
+            BroadcastStatusType.BROADCASTING,
+        )),
         BroadcastMessage.reference.in_(references_to_original_broadcast),
         BroadcastMessage.service_id == service_id
     ).one()

app/v2/broadcast/post_broadcast.py

@@ -3,6 +3,7 @@ from itertools import chain
 from flask import current_app, jsonify, request
 from notifications_utils.polygons import Polygons
 from notifications_utils.template import BroadcastMessageTemplate
+from sqlalchemy.orm.exc import MultipleResultsFound
 
 from app import api_user, authenticated_service
 from app.broadcast_message.translators import cap_xml_to_dict
@@ -105,10 +106,17 @@ def create_broadcast():
 
 
 def _cancel_or_reject_broadcast(references_to_original_broadcast, service_id):
-    broadcast_message = dao_get_broadcast_message_by_references_and_service_id(
-        references_to_original_broadcast,
-        service_id
-    )
+    try:
+        broadcast_message = dao_get_broadcast_message_by_references_and_service_id(
+            references_to_original_broadcast,
+            service_id
+        )
+    except MultipleResultsFound:
+        raise BadRequestError(
+            message='Multiple alerts found - unclear which one to cancel',
+            status_code=400,
+        )
+
     if broadcast_message.status == BroadcastStatusType.PENDING_APPROVAL:
         new_status = BroadcastStatusType.REJECTED
     else:

tests/app/v2/broadcast/sample_cap_xml_documents.py

@@ -79,6 +79,15 @@ WAINFLEET_CANCEL_WITH_EMPTY_REFERENCES = WAINFLEET_CANCEL.format(
     "<references></references>"
 )
 
+WAINFLEET_CANCEL_WITH_WINDMERE_REFERENCES = WAINFLEET_CANCEL.format(
+    "<references>"
+    # Wainfleet
+    "www.gov.uk/environment-agency,50385fcb0ab7aa447bbd46d848ce8466E,2020-02-16T23:01:13-00:00,"
+    # Windemere
+    "www.gov.uk/environment-agency,4f6d28b10ab7aa447bbd46d85f1e9effE,2020-02-16T19:20:03+00:00"
+    "</references>"
+)
+
 UPDATE = """
     <alert xmlns="urn:oasis:names:tc:emergency:cap:1.2">
       <identifier>PAAQ-4-mg5a94</identifier>

tests/app/v2/broadcast/test_post_broadcast.py

@@ -220,6 +220,38 @@ def test_cancel_request_does_not_cancel_broadcast_if_reference_does_not_match(
     assert response_for_cancel_json["errors"] == expected_error
 
 
+def test_cancel_raises_error_if_multiple_broadcasts_referenced(
+    client,
+    sample_broadcast_service,
+):
+    auth_header = create_service_authorization_header(service_id=sample_broadcast_service.id)
+
+    for cap_document in (
+        sample_cap_xml_documents.WAINFLEET,
+        sample_cap_xml_documents.WINDEMERE,
+    ):
+        response_for_create = client.post(
+            path='/v2/broadcast',
+            data=cap_document,
+            headers=[('Content-Type', 'application/cap+xml'), auth_header],
+        )
+        assert response_for_create.status_code == 201
+
+    # try to cancel two broadcasts with one request
+    response_for_cancel = client.post(
+        path='/v2/broadcast',
+        data=sample_cap_xml_documents.WAINFLEET_CANCEL_WITH_WINDMERE_REFERENCES,
+        headers=[('Content-Type', 'application/cap+xml'), auth_header],
+    )
+    response_for_cancel_json = json.loads(response_for_cancel.get_data(as_text=True))
+
+    assert response_for_cancel.status_code == 400
+    assert response_for_cancel_json["errors"] == [{
+        'error': 'BadRequestError',
+        'message': 'Multiple alerts found - unclear which one to cancel',
+    }]
+
+
 def test_cancel_request_does_not_cancel_broadcast_if_service_id_does_not_match(
     client,
     sample_broadcast_service,
@@ -253,6 +285,56 @@ def test_cancel_request_does_not_cancel_broadcast_if_service_id_does_not_match(
     assert response_for_cancel.status_code == 404
 
 
+@pytest.mark.parametrize("is_approved, expected_cancel_tasks", (
+    (True, 1),
+    (False, 0),
+))
+def test_same_broadcast_cant_be_cancelled_twice(
+    mocker,
+    client,
+    sample_broadcast_service,
+    is_approved,
+    expected_cancel_tasks,
+):
+    mock_send_broadcast_event_task = mocker.patch(
+        'app.celery.broadcast_message_tasks.send_broadcast_event.apply_async'
+    )
+    auth_header = create_service_authorization_header(service_id=sample_broadcast_service.id)
+
+    # create a broadcast
+    response_for_create = client.post(
+        path='/v2/broadcast',
+        data=sample_cap_xml_documents.WAINFLEET,
+        headers=[('Content-Type', 'application/cap+xml'), auth_header],
+    )
+    assert response_for_create.status_code == 201
+
+    response_json_for_create = json.loads(response_for_create.get_data(as_text=True))
+
+    broadcast_message = dao_get_broadcast_message_by_id_and_service_id(
+        response_json_for_create["id"], response_json_for_create["service_id"]
+    )
+    # approve broadcast
+    if is_approved:
+        broadcast_message.status = 'broadcasting'
+
+    first_response_for_cancel = client.post(
+        path='/v2/broadcast',
+        data=sample_cap_xml_documents.WAINFLEET_CANCEL_WITH_REFERENCES,
+        headers=[('Content-Type', 'application/cap+xml'), auth_header],
+    )
+    assert first_response_for_cancel.status_code == 201
+
+    second_response_for_cancel = client.post(
+        path='/v2/broadcast',
+        data=sample_cap_xml_documents.WAINFLEET_CANCEL_WITH_REFERENCES,
+        headers=[('Content-Type', 'application/cap+xml'), auth_header],
+    )
+    assert second_response_for_cancel.status_code == 404
+
+    assert len(mock_send_broadcast_event_task.call_args_list) == expected_cancel_tasks
+
+
 def test_large_polygon_is_simplified(
     client,
     sample_broadcast_service,