socket.io, we can execute a callback function over WebSockets (or a relevant alternative). The function is defined client side, yet called server side (and vice versa). This can be a very powerful way to share processing resources and functionalities between clients and servers—it's called Remote Procedure Calls (RPC).
In this recipe, we'll create a way for the server to call a client-side function that squares a number, and for the client to call a server-side function that sends a Base64 encoded (http://en.wikipedia.org/wiki/Base64) sentence back to the client.
We simply need to create a new folder with the new
On our server, as before, we load ...