> The server doesn't need to know anything about the UI state here.
As always: "it depends". I've built many use-cases where the server did really need to know about this. When we needed the intermediate state to be stored so that a user could pick up where she left. Or when we needed the telemetry/events of intermediate states being sent (e.g. "your ticket is now reserved for 45 minutes please proceed to payment") and so on.
What's more, and more important though, is that no:
> But it's also wasteful.
It is hardly wasteful. Hell, your "ga.js" HTTP call is probably heavier than doing a simple call to proceed the state-machine over HTTP. HTTP certainly isn't the problem: most likely the choice of a bulky and sluggish backend language/framework is, though.
As always: "it depends". I've built many use-cases where the server did really need to know about this. When we needed the intermediate state to be stored so that a user could pick up where she left. Or when we needed the telemetry/events of intermediate states being sent (e.g. "your ticket is now reserved for 45 minutes please proceed to payment") and so on.
What's more, and more important though, is that no:
> But it's also wasteful.
It is hardly wasteful. Hell, your "ga.js" HTTP call is probably heavier than doing a simple call to proceed the state-machine over HTTP. HTTP certainly isn't the problem: most likely the choice of a bulky and sluggish backend language/framework is, though.