Trying workaround for labeling scheduled queries (#105)

* trying workaround for labeling scheduled queries

* path fix?

* path fix?

* tweaked formatting

* proper support for multiple labels

* removed need for separate template

* fixed bad concat

terraform/bigquery_scheduled_data_transfer/main.tf

@@ -23,12 +23,15 @@ resource "google_bigquery_data_transfer_config" "default" {
   destination_dataset_id = var.destination_dataset_id
 
   params = {
-    query = templatefile(
-      var.query_template,
-      merge(var.query_variables, { interval = try(local.bigquery_interval_mappings[var.interval], var.interval) })
-    )
     destination_table_name_template = var.destination_table_name_template
-    write_disposition               = var.write_disposition
+    query = join("", [
+      length(var.labels) > 0 ? format("SET @@query_label = \"%s\";\n\n", join(",", [for key, value in var.labels : format("%s:%s", key, value)])) : "",
+      templatefile(
+        var.query_template,
+        merge(var.query_variables, { interval = try(local.bigquery_interval_mappings[var.interval], var.interval) })
+      )
+    ])
+    write_disposition = var.write_disposition
   }
 
   # formatting rules are quite hard to generalize, see: https://cloud.google.com/appengine/docs/flexible/scheduling-jobs-with-cron-yaml#cron_yaml_The_schedule_format