TYPO3扩展：从javascript访问TYPO3会话变量？

Question

This may sound a little unprecise, but is it possible to change the TYPO3 session variable

$GLOBALS["TSFE"]->fe_user->setKey('ses', 't_minus', 0);

from javascript somehow for the variable to be processed within a listAction to specify certain records to be shown or not?

In more detail: I work on an extension for a calendar. The calendar is generated in javascript (that's the part i'm not responsible for). The listAction basically generates a JSON object or records which have a unix timestamp within a specific interval (2 weeks in the past, 3 weeks in the future). The javascript has a button "one week forward"/"one week back". One week back should subtract 604800 (1 week) from the session variable, one week forward add 604800 (1 week) to the session variable.

In the listAction the session variable adjusts the timestamp interval (n weeks forward/backward) or rather which records should be put into the JSON object.

Is it possible to access the session variable from javascript or does this violate safety requirements?

Answer 1

I would create a PHP function to change this session variable (eg with eID functionality) and call the function via AJAX in JavaScript. More see here: https://seethroughweb.com/ajax-with-typo3/

(Sorry, couldn't find a better manual in english, you need to use the new class names)

Answer 2

It is not possible to change TYPO3 session content directly via javascript. It may be that you can access the PHP session cookie via javascript - I am not quite sure on that -, but the session variables are stored in the TYPO3 DB. They are serialized and encrypted via PHP and you won't be able to get access on these via Javascript. This is only possible via PHP.

What you could do: create oneWeekForwardAction and oneWeekBackAction in your controller. Read your session cookie and modifie it to your needs. These actions can be activated via Ajax. For this to happen you have to create the appropriate links with the f:uri.action in advance in your Fluid template! Place these strings somewhere in your JSON object. Then you can connect these links to the click events.

Don't forget to generate a special AJAX page type with page.config.disableAllHeaderCode . If you search for this and Ajax you will find examples, fe this one:

[ http://www.sklein-medien.de/tutorials/detail/erstellung-einer-typo3-extension-mit-ajax-aufruf/]

It is from 2016 und uses Extbase/Fluid.

Answer 3

It's not a question of safety. The idea of a session is, to bind to the same data on the server over a series of multiple HTTP requests. Javascript lives in the Browser. There is no direct access from JavaScript to the data on the server.

If you are responsible for JS only, it's the job of the other person to provide an interface to the session data for you.

And yes, I think it a good idea to synchronise your calculations in the Browser with the data in the server else calendar datas get quickly out of sync. I would even go that far, that the server should be responsible for this kind of calculations, as it is more reliable than JS. So the guy responsible for PHP should do the main job and provide results to you ie via AJAX.