Handle service account casing in google_bigquery_dataset_access (Goog…

…leCloudPlatform#11875)

mmv1/products/bigquery/DatasetAccess.yaml

@@ -134,6 +134,7 @@ properties:
       - 'routine'
     diff_suppress_func: 'resourceBigQueryDatasetAccessIamMemberDiffSuppress'
     custom_expand: 'templates/terraform/custom_expand/string_to_lower_case.go.tmpl'
+    custom_flatten: 'templates/terraform/custom_flatten/string_to_lower_case.go.tmpl'
   - name: 'groupByEmail'
     type: String
     description: An email address of a Google Group to grant access to.
@@ -148,6 +149,7 @@ properties:
       - 'routine'
     diff_suppress_func: 'resourceBigQueryDatasetAccessIamMemberDiffSuppress'
     custom_expand: 'templates/terraform/custom_expand/string_to_lower_case.go.tmpl'
+    custom_flatten: 'templates/terraform/custom_flatten/string_to_lower_case.go.tmpl'
   - name: 'domain'
     type: String
     description: |

mmv1/templates/terraform/custom_flatten/string_to_lower_case.go.tmpl

@@ -0,0 +1,19 @@
+{{/*
+	The license inside this block applies to this file
+	Copyright 2024 Google Inc.
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+	Unless required by applicable law or agreed to in writing, software
+	distributed under the License is distributed on an "AS IS" BASIS,
+	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+	See the License for the specific language governing permissions and
+	limitations under the License.
+*/ -}}
+func flatten{{$.GetPrefix}}{{$.TitlelizeProperty}}(v interface{}, d *schema.ResourceData, config *transport_tpg.Config) interface{} {
+  if v == nil {
+    return nil
+  }
+
+  return strings.ToLower(v.(string))
+}