Issue description

The configuration field cache_zone of the cache zone in the plug-in is a required item. I think this is unfriendly to some users who are not familiar with this field. They don't know what needs to be done here. In my opinion, cache_zone should be optional and have a default value. In this way, for novice users, they do not need to care about what needs to be configured in this field. For familiar users, they can set this field according to their needs.

......
properties = {
        cache_zone = {
            type = "string",
            minLength = 1
        },
......
},
required = {"cache_zone"},