Session sometimes works, sometimes doesn't?

Questions
1

Silverstripe Version:
4.4.5
Question:
OK, this is just straight out of the official doc:

Here I see the value saved into session

    $session = $request->getSession();
    $session->set('MyVal', '1');
    Debug::show($session);

image

Now I take out $session->set('MyVal', '1');

$session = $request->getSession();
Debug::show($session);

and — ???
image

I had this issue before - but it resolved itself before I could figure out what was going no - now tonight it came up again :confused:

However, if I save data via $_SESSION, it works (save and read, no problem) - and it will work if I call “save” function and pass in $request

$session->save($request);

So, how does it really work? The documentation seems clear, but the same issue comes and goes and I’m already confused like

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image640×640 48.8 KB

2

It looks like you’ve already found the answer.
Session component does not persist its state on every “Session::set”, but does it only once per request on Session::save invocation. That happens in SessionMiddleware. Note that the middleware does not ::start the session, it merely performs ::init. The ::start is done lazily within the ::save method.
When you do Debug::show($session), it flushes HTTP headers before the middleware can persist the session, so the cookie with the session id cannot be set.

1 Like
3

Thanks @dnsl48 ! In the next morning when I had a closer look on Session::class, I found SilverStripe has its own session data built on top of $_SESSION, and yes, like you said, it won’t get properly called until later stage.

Actually, I also figured out where my problem is:

When I did Session::set, I did it in handleAction function, and then die;- this is why it couldn’t get saved!

Cheers
Leo