Laravel 3闪烁的变量并不总是在会话中

Question

I'm using the following line to redirect to my base index action in a bundle:

return Redirect::to_action('mybundle::base@index')->with("prevCommands", $prevCommands)->with("result", $result)->with_input();

Redirection works but when I'm grabbing the info from the Session I randomly get null values, the following code is in my index action:

$view['prevCommands']  = (array)Session::get('prevCommands');
$view['result']        = (string)Session::get('result');

The combination above seems to only randomly work, and it tends to work better if the server takes a bit longer to respond. I checked that the variables are correctly populated all the time before redirecting.

When it happens both values come back as null at once. There's never a case where only one of them is set.

Answer 1

It sounds like you're using the cookie session driver, and that it's running out of space. I'd recommend changing to any of the other drivers (except 'memory').

Laravel 3 offers a number of session drivers . 'cookie' is the default driver as it requires zero set up, but it has a size limit of 4K. For anything more serious you should consider a different driver. In order of ease of set up...

• file saves each session as a file in storage/sessions, so you need to make sure this location is writable, and if you're on a shared server that it has suitable permissions.
• database uses a table in your default database connection, the documentation describes the necessary schema.
• memcached and redis use the respective service, they don't require much set up once you have the service installed and working.

It's worth mentioning the memory driver, this is useful only for testing as the data is not persistent (lost at the end of the request).

Answer 2

Never mind, I figured it out, it began to make sense once I noticed that the cookie driver for Sessions in Laravel 3 does not actually use PHP's built in Cookie Session mechanism, it actually stores the whole payload in a cookie.

Since cookies have a limited size allowance this mechanism breaks if the total data stored exceeds 4K, bearing in mind all the "padding" characters for storing an actual array in the session.

This also made me aware that my application's design is faulty, I should not flash such huge amounts of data to the session.