diff --git a/spec/lib/synapse/service_watcher_zookeeper_spec.rb b/spec/lib/synapse/service_watcher_zookeeper_spec.rb
index 2d5e13eb..c4dd062f 100644
--- a/spec/lib/synapse/service_watcher_zookeeper_spec.rb
+++ b/spec/lib/synapse/service_watcher_zookeeper_spec.rb
@@ -63,7 +63,7 @@
     [ service_data['host'], service_data['port'], service_data['name'], service_data['weight'],
       service_data['haproxy_server_options'], service_data['labels'] ]
   }
-  let(:config_for_generator_string) { config_for_generator.to_json }
+  let(:config_for_generator_string) { [config_for_generator.to_json] }
   let(:parsed_config_for_generator) do
     {
       "haproxy" => config_for_generator_haproxy