[10.x] Ensure array driver expires values at the expiry time

[timacdonald]

The array cache driver's logic for determining when a key has expired is wrong.

It currently requires the time to be PAST the expiry - but the value indicates when the key expires at, thus if it is currently the time that it expires, it should have expired.

This means the array driver does not currently function like Redis. You can demo this yourself using the following script to test.

Make sure to test with array and with redis to see the difference.

You will notice that the array driver cannot make another hit until 1 second past the NEXT minute while Redis is able to make a hit at the very start of the second (give or take a few hundred milliseconds for communicating with Redis itself).

Artisan::command('limit', function () {
    while (now()->second !== 0) {
        echo '.';

        usleep(100_000);
    }

    echo PHP_EOL;

    $continue = true;

    while ($continue) {
        $continue = RateLimiter::attempt('echo-message', 10, function() {
            echo 'Executing rate limited code at '.now()->toDateTimeString().PHP_EOL;
        });
    }

    sleep(1);

    while (now()->second !== 0) {
        echo '.';

        usleep(100_000);
    }

    echo PHP_EOL;

    $continue = true;

    while (true) {
        $continue = RateLimiter::attempt('echo-message', 10, function() {
            echo 'Executing rate limited code at '.now()->toDateTimeString('m').PHP_EOL;
        });
    }
});

Array

Waiting until the start of the minute...
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Executing rate limited code at 2023-09-22 05:56:00
Waiting until the start of the NEXT minute...
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.........
Executing rate limited code at 2023-09-22 05:57:01.000

Redis

Waiting until the start of the minute...
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Executing rate limited code at 2023-09-22 05:50:00
Waiting until the start of the NEXT minute...
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.......
Executing rate limited code at 2023-09-22 05:51:00.054

The included test is one I was already writing that lead me down the path of testing all of this - so I left it in for us.