Backend Ajax protocol

Discussion

There should be a standard JSON protocol between the LS backend and Ajax calls to check for errors, permissions and if the user still is logged in. A suggestion would be to wrap $.ajax in a function that checks this for you, like $.lsAjax.

All server Ajax calls must return a JSON in the following format:

{
  result: mixed,
  error: {code: int, message: string},
  loggedIn: boolean,
  hasPermission: boolean,
}

Of course there needs to be server side support for this protocol, too, with helper functions to output correct JSON code, e.g. Ajax::outputResult or Ajax::outputError($code, $message).

Preferably, the function should be able to show an error if server throws 500.

Backbone

Since Javascript library Backbone might be used in the future, it would be nice to know how they handle stuff like this.

Implementation

A first prototype of the backend classes can be seen here.