Fix Static labels and document supported backends

Author: Carson Anderson

auth_server/authn/static_auth.go

@@ -23,6 +23,7 @@ import (
 
 type Requirements struct {
 	Password *PasswordString `yaml:"password,omitempty" json:"password,omitempty"`
+	Labels   Labels          `yaml:"labels,omitempty" json:"labels,omitempty"`
 }
 
 type staticUsersAuth struct {
@@ -54,7 +55,7 @@ func (sua *staticUsersAuth) Authenticate(user string, password PasswordString) (
 			return false, nil, nil
 		}
 	}
-	return true, nil, nil
+	return true, reqs.Labels, nil
 }
 
 func (sua *staticUsersAuth) Stop() {

docs/Labels.md

@@ -2,6 +2,8 @@
 
 Labels can be used to reduce the number ACLS needed in large, complex installations.
 
+Labels are only supported for certain auth backends. As of right now labels are only supported when using Static Authentication or Mongo Authentication.
+
 ## Label Placeholders
 
 Label placeholders are available for any label that is assigned to a user.