Understood, but doesn't make sense to look up for the server and fingerprint at the 'request', this should be done at the 'model'. 

If I'm using a model (the common use case), the current fingerprint should be filled automatically (because we've this data from when we got the instance), this is why I added a 'set_tags' method a the server model (https://github.com/fog/fog/pull/2863/files#diff-7740fa41055f4cd4d0dedbab4914f293R157). 

But if  I'm using directly the 'request', then I must provide the fingerprint by myself. 

Makes sense?