anchor.diff:  -spec s3_model() -> maps:map().
   s3_model() ->
       #{
  +        %% The type of storage.
  +        type => {equal, <<"s3">>},
           %% The Id of storage.
           id => {string, optional},
           %% The name of storage.
  
positive.code: -spec posix_model() -> maps:map().
  posix_model() ->
      #{
          %% The Id of storage.
          id => {string, optional},
          %% The name of storage.
  
negative.code:         %% LUMA API Key, must be identical with API Key in external LUMA
          %% service.
          lumaApiKey => {string, optional},
          %% The name of the volume to use as a storage backend.
          volume => string,
          %% The hostname (IP address or FQDN) of GlusterFS volume server.
  