allow debug to only be set by env var as an override of static.json

README.md

@@ -68,6 +68,8 @@ You can disable the access log and change the severity level for the error log.
 
 By default `access` is set to `true` and `error` is set to `error`.
 
+The environment variable `STATIC_DEBUG` can be set, to override the `error` log level to `error`.
+
 
 #### Custom Routes
 You can define custom routes that combine to a single file. This allows you to preserve routing for a single page web application. The following operators are supported:

scripts/config/lib/nginx_config.rb

@@ -54,7 +54,7 @@ class NginxConfig
     end
 
     json["error_page"] ||= nil
-    json["debug"] ||= ENV['STATIC_DEBUG']
+    json["debug"] = ENV['STATIC_DEBUG']
 
     logging = json["logging"] || {}
     json["logging"] = DEFAULT[:logging].merge(logging)