Actions

Backend Ajax protocol

From LimeSurvey Manual

Revision as of 19:08, 28 September 2016 by Olle (talk | contribs) (→‎Implementation)

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 LS.ajax.

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.

Some questions:

  • Would we need to duplicate the model code in both backend and frontend?
  • How much of the CRUD will happen on client?
  • What much would backbone replace Yii?

Implementation

A first prototype of the backend classes can be seen here. Instead of a helper, this class can actually be put into LSYiiController, making it available to all controllers in LS.

Example:

public function indexAction()
{
  $this->ajax->outputSucces(gT('Success!'));
}