ksamborski/apcu-memo

apcumemo

PHP library for memoization function results based on it's arguments., _(*1)

Requirements

You need to have acpu extension installed for php >= 7.0.0, _(*2)

Installation

composer require ksamborski/apcu-memo

Basic usage

Functional paradigm teaches us that pure functions are the way to go. They provide two main features:, _(*3)

• because their result depends only on their arguments they can be easly tested (you don't need any mocks or stubs)
• because they have no side effects they can be easly cached

Consider this example:, _(*4)

use APCuMemo\APCuMemo;

function sumrange($a, $b)
{
    return APCuMemo::memoize(
        function(...$_) use ($a, $b) {
            return array_reduce(range($a, $b), function ($product, $item) { return $product + $item; }, 1);
        },
        [ 'ttl' => 5 ],
        "sumrange",
        $a,
        $b
    );
}

$start = microtime(true);
echo sumrange((int) $_GET['a'], (int) $_GET['b']);
$elapsed = microtime(true) - $start;
echo " " . ($elapsed * 1000) . " ms";

We have a simple function that sums integers from $a to $b. It can take some time but when we compute it for the first time then we can cache it. Notice the 'ttl' parameter. It is set to 5 seconds and means that if nobody asks us for the same range within 5 seconds it will forget the result. But every request for cached value will reset the ttl. That way we can have only mostly used values in cache., _(*5)

Let's see it in action. For $a = 1 and $b = 1831233 it will return something like:, _(*6)

1676708065762 283.94412994385 ms

And the followed requests will return:, _(*7)

1676708065762 0.030040740966797 ms