An 'authorizer' manages known users and their access policies. Authorizers are configured using two properties in the nifi-registry.properties file:
nifi.registry.security.authorizers.configuration.fileproperty specifies the configuration file where authorizers are defined. By default, the authorizers.xml file located in the root installation conf directory is selected.
nifi.registry.security.authorizerproperty indicates which of the configured authorizers in the authorizers.xml file to use.