how should I used "es6 import" with advanced methods Meteor package from client server or both?

I have my method here : imports/api/Books/methods

Following the guide, we can import this method from server or from both (server and client) if we want optimistic UI.

However, if we use this package : https://github.com/meteor/validated-method : is it necessary to import from both ? Can we just import from server ?

Thank you

update

I already read this :

• https://docs.meteor.com/api/methods.html
• https://github.com/meteor/validated-method
• https://blog.meteor.com/optimistic-ui-with-meteor-67b5a78c3fcf
• https://github.com/cleverbeagle/pup/issues/53
• https://forums.meteor.com/t/import-from-client-to-server/37227/17

Optimistic UI works by running the method against the minimongo on the client to give you the most likely result from running the query on the server. Therefore the method needs to be available from both the client and server to enable optimistic UI.

If you want to do something differently on the client or server you have the isSimulation boolean that will be true in the case it is running on the client and false on the server side.

The relevant docs