VED-242: Updated error messaging when search requests exceed 1MB limit (#1448)

* VED-242: Updated error messaging when search requests exceed 1MB limit

* Rename MAX_SEARCH_RESPONSE_SIZE_BYTES constant

Author: ariagraham-nhs

lambdas/backend/src/constants.py

@@ -2,4 +2,4 @@
 
 GENERIC_SERVER_ERROR_DIAGNOSTICS_MESSAGE = "Unable to process request. Issue may be transient."
 # Maximum response size for an AWS Lambda function
-MAX_RESPONSE_SIZE_BYTES = 6 * 1024 * 1024
+MAX_SEARCH_RESPONSE_SIZE_BYTES = 1 * 1024 * 1024

lambdas/backend/src/controller/fhir_controller.py

@@ -11,7 +11,7 @@
 from fhir.resources.R4B.identifier import Identifier
 
 from common.get_service_url import get_service_url
-from constants import MAX_RESPONSE_SIZE_BYTES
+from constants import MAX_SEARCH_RESPONSE_SIZE_BYTES
 from controller.aws_apig_event_utils import (
     get_multi_value_query_params,
     get_path_parameter,
@@ -213,7 +213,7 @@ def _search_immunizations_by_target_disease(self, search_params: dict[str, list[
     def _create_search_response(self, search_bundle: Bundle) -> dict:
         search_response_json = search_bundle.json(use_decimal=True)
 
-        if len(search_response_json) > MAX_RESPONSE_SIZE_BYTES:
+        if len(search_response_json) > MAX_SEARCH_RESPONSE_SIZE_BYTES:
             raise TooManyResultsError("Search returned too many results. Please narrow down the search")
 
         prepared_search_bundle = self._prepare_search_bundle(search_response_json)

lambdas/backend/tests/controller/test_fhir_controller.py

@@ -1207,7 +1207,7 @@ def test_search_immunizations_returns_a_validation_error_when_optional_params_in
                 )
                 self.service.search_immunizations.assert_not_called()
 
-    @patch("controller.fhir_controller.MAX_RESPONSE_SIZE_BYTES", 5)
+    @patch("controller.fhir_controller.MAX_SEARCH_RESPONSE_SIZE_BYTES", 5)
     def test_search_immunizations_raises_error_if_too_many_results_found(self):
         """it should return an error if there are too many results in the response for Lambda to handle. In reality,
         highly unlikely. If a concern, pagination should be implemented."""

lambdas/backend/tests/controller/test_fhir_controller_target_disease.py

@@ -288,7 +288,7 @@ def test_search_by_target_disease_with_mixed_valid_and_invalid_returns_200_with_
         self.assertIn("invalid-no-pipe", call_args[1]["invalid_target_diseases"][0])
         self.assertIn("Invalid format", call_args[1]["invalid_target_diseases"][0])
 
-    @patch("controller.fhir_controller.MAX_RESPONSE_SIZE_BYTES", 5)
+    @patch("controller.fhir_controller.MAX_SEARCH_RESPONSE_SIZE_BYTES", 5)
     def test_search_by_target_disease_returns_400_when_response_too_large(self):
         """it should return the same narrow-the-search error for oversized target-disease searches"""
         self.mock_redis.hget.side_effect = self._hget_target_disease_codes_and_mmr