Hi Takeshi,
There is no direct “anonymous” access level, you should file a feature request for this.
You could fake it by using an API token for a non-existent user “anonymous", and then granting access based on username.
However, the access level for this user would be the combination of ACL policies matching "group: api_token_group" and the "username: anonymous”. if you want to allow api_token_group to do other things, but disallow this “anonymous” user, you would have to add DENY rules for everything you don’t want “anonymous” to do. Basically you could start with the admin.aclpolicy, but change `- allow: “*”`to `- deny: “*”`, except for the Key storage.
You could use two ways to create the anonymous token, either generate a random one via the API, for the “anonymous” username:
anonymous: anon
Then use the token in a URL parameter `?authtoken=anon` in your later requests.