Set default value for miniomaha server config file

For most cases, we use miniomaha.conf as miniOmaha server configuration file.
Let's set this as the default value.

TEST=Start from two different working directories without config
     file specified.

Change-Id: I75bf8cc36908902686b9899d418c6970d524291c
Reviewed-by: Hung-Te Lin <>
Commit-Ready: Vic Yang <>
Tested-by: Vic Yang <>
diff --git a/factory_setup/ b/factory_setup/
index 9f4d3a4..ed721d2 100755
--- a/factory_setup/
+++ b/factory_setup/
@@ -126,13 +126,15 @@
 if __name__ == '__main__':
+  base_path = os.path.dirname(os.path.abspath(sys.argv[0]))
   usage = 'usage: %prog [options]'
   parser = optparse.OptionParser(usage)
   parser.add_option('--data_dir', dest='data_dir',
                     help='Writable directory where static lives',
-                    default=os.path.dirname(os.path.abspath(sys.argv[0])))
+                    default=base_path)
   parser.add_option('--factory_config', dest='factory_config',
-                    help='Config file for serving images from factory floor.')
+                    help='Config file for serving images from factory floor.',
+                    default=base_path + "/miniomaha.conf")
   parser.add_option('--port', default=8080,
                     help='Port for the dev server to use.')
   parser.add_option('--proxy_port', default=None,