Cacheable – A transparent caching library

Installation

Using composer:

composer require sci/cacheable

Usage

Lets say, you have a class Foo, implementing a method Foo::bar() with quite high time/resource consumption:

class Foo
{
    public function bar($a, $b)
    {
        // make some hard things with $a and $b
        ...
        
        return ...; // some result
    }
}

$foo = new Foo();

$bar = $foo->bar(1, 2); // takes some amount of time

// and later, again...
$bar = $foo->bar(1, 2); // takes the same amount of time, again

If there are no side-effects, the result of Foo::bar() is determined only by its arguments $a and $b. So you could use some cache, if eventuelly the method is called again. To avoid messing around with cache keys, you can use sci\cacheable:

use Sci\Cacheable;
use Sci\CacheTrait;

class Foo implements Cacheable
{
    use CacheTrait;

    public function bar($a, $b)
    {
        // make some hard things with $a and $b
        ...
        
        return ...; // some result
    }
}

$foo = new Foo();
$foo->setCache(/* any PSR-6 cache pool interface */)

$bar = $foo->cache()->bar(1, 2); // 1st call takes some time, but now, the result is stored into cache

// and later, again...
$bar = $foo->cache()->bar(1, 2); // 2nd call's result comes directly from cache

en détail

• A class to be cached (Foo in example above) implements the interface Sci\Cacheable (which demands a method cache()).
• This can be done using Sci\CacheTrait (which additially provides a method setCache()).
• The method setCache gets as first argument a service, implementing Psr\Cache\CacheItemPoolInterface.
  • This cache pool is the actual cache backend.
  • An optional second argument to setCache is the default TTL (time to live) for all cached values.
• To use the cache, method calls are proxied through the method cache(), e.g. instead of $foo->bar(1, 2), now we use $foo->cache()->bar(1, 2).
  • Method cache() returns $this, i.e. it acts in a transparent way (fluent interface).
  • An optional argument for cache() allows to specify a TTL, different from the default one.

Implementation

License

All contents of this package are licensed under the MIT license.