以只读模式启动会话

Question

My problem is the following:

I have a page which runs a series of AJAX calls e.g.

$.ajax({ url: "/user/post1" });
$.ajax({ url: "/user/post2" });
$.ajax({ url: "/user/post3" });
...
$.ajax({ url: "/user/postN" }); 

(I've determined the ids beforehand)

I've also got:

$.ajax({ url: "/user/modifysessiondata" }); 

Now the problem is that I need to start the session in each and every request (to get the current user) and in addition "/user/modifysessiondata" also needs to modify session data.

However I've noticed that if I just execute all AJAX requests at once it's possible that if a /user/postX request starts before /user/modifysessiondata request and ends after that then it will save the session data as it was when the request was called and therefore will overwrite the session data that was set by the 2nd call.

My question is:

Is it possible to flag the session started in a specific request as "Read only"? Would I need to create a new custom StartSession middleware for this?

Am I just doing something completely ridiculous?

Note: To clarify I'm talking about the Laravel session. I am using a redis backed session storage.

Answer 1

In case it helps anyone this is what I ended up doing:

In my RouteServiceProvider.php boot() method:

Route::group([
    'middleware' => 'readonly',
    'namespace' => $this->namespace,
], function ($router) {
    Route::get("user/{post}","UserController@getPost");
});

In my Kernel.php:

'readonly' => [            
        \App\Http\Middleware\EncryptCookies::class,
        \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
        \App\Http\Middleware\StartReadOnlySession::class,            
        \Illuminate\View\Middleware\ShareErrorsFromSession::class,
        \App\Http\Middleware\VerifyCsrfToken::class,   
        'bindings',
 ]

This was basically copied from the web route group with the exception of StartSession swapped for StartReadOnlySession

Here's my StartReadOnlySession code (the punchline of the issue):

use Illuminate\Session\Middleware\StartSession;
class StartReadOnlySession extends StartSession {
    public function terminate($request, $response) { /* Does nothing */ }
}

This this starts the session but does not save it when the request terminates. Everything else behaves identically.