Allow updating Cloud Function's source

Author: Olivier Cervello

main.tf

@@ -14,6 +14,12 @@
  * limitations under the License.
  */
 
+locals {
+  // we append the app hash to the filename as a temporary workaround for https://github.com/terraform-providers/terraform-provider-google/issues/1938
+  md5_hash = "${lower(replace(base64encode(data.archive_file.main.output_md5), "=", ""))}"
+  storage_object_name = "event_function-${random_string.random_suffix.result}-${local.md5_hash}.zip"
+}
+
 /******************************************
 	Scheduled Function Definition
  *****************************************/
@@ -94,7 +100,7 @@ resource "google_storage_bucket" "main" {
 }
 
 resource "google_storage_bucket_object" "main" {
-  name                = "event_function-${random_string.random_suffix.result}.zip"
+  name                = "${local.storage_object_name}"
   bucket              = "${google_storage_bucket.main.name}"
   source              = "${data.archive_file.main.output_path}"
   content_disposition = "attachment"