Quick Start

Quick Start

Five minutes from composer require to a working cache.

1. Build a handler

Use the Cache::create() factory. Its first argument is a handler class; the second is an options array.

<?phpdeclare(strict_types=1);
require__DIR__ . '/vendor/autoload.php';
useInitPHP\Cache\Cache;
useInitPHP\Cache\Handler\File;
$cache = Cache::create(File::class, [
'path' => __DIR__ . '/var/cache', // the directory must exist and be writable
]);

create() returns an object implementing CacheInterface, which extends Psr\SimpleCache\CacheInterface. You can type-hint either interface anywhere in your app.

2. Store and read

$cache->set('greeting', 'Hello'); // no TTL → kept until deleted$cache->set('token', 'abc123', 3600); // expires in 3600 seconds$cache->get('greeting'); // "Hello"$cache->get('unknown'); // null (default)$cache->get('unknown', 'fallback'); // "fallback"$cache->has('greeting'); // true$cache->delete('greeting'); // true$cache->clear(); // wipe everything this handler owns

Values keep their type and structure — strings, ints, floats, booleans, null, arrays and objects all round-trip exactly:

$cache->set('config', ['debug' => true, 'level' => 5]);
$cache->get('config'); // ['debug' => true, 'level' => 5]

3. The read-through pattern

The most common use of a cache: return the stored value, or compute and store it on a miss.

$report = $cache->get('daily-report');
if ($report === null) {
$report = build_expensive_report(); // your slow code$cache->set('daily-report', $report, 86400); // cache for a day
}
return$report;

If null is a legitimate value for you, use has() to tell a miss from a stored null — see Keys, TTL & Values.

4. Switch the backend in one line

Because every handler shares the same API, moving from the filesystem to Redis is a one-line change:

useInitPHP\Cache\Handler\Redis;
$cache = Cache::create(Redis::class, [
'host' => '127.0.0.1',
'port' => 6379,
'database' => 0,
]);
// ...the rest of your code is unchanged.$cache->set('user:42', ['name' => 'Jane'], 3600);

See the handler pages for each backend's options.

5. Bulk operations and counters

// Many at once (accepts arrays or any iterable)$cache->setMultiple(['a' => 1, 'b' => 2, 'c' => 3], 600);
$cache->getMultiple(['a', 'b', 'missing'], 0); // ['a'=>1, 'b'=>2, 'missing'=>0]$cache->deleteMultiple(['a', 'b']);
// Atomic-style counters (return the new value)$cache->increment('views'); // 1$cache->increment('views', 5); // 6$cache->decrement('views', 2); // 4

See Bulk Operations and Counters.

What just happened

1. create() instantiated the handler, verified the runtime supports it, and merged your options over the defaults.
2. set() serialised the value and wrote it to the backend, with the TTL you gave (or none).
3. get() read it back, returned your $default on a miss, and honoured the expiry.

Things worth knowing immediately

• Keys are validated. A key must be a non-empty string with none of the reserved characters {}()/\@:; otherwise an InvalidArgumentException is thrown. See Keys, TTL & Values.
• A zero or negative TTL deletes the item (and returns true).
• The default key prefix is cache_. It scopes clear() so caches sharing one backend don't wipe each other. Change it with the prefix option.
• get() never calls your default. A callable default is returned as a plain value, per PSR-16.

Next steps

• The Cache Factory — instances, options, error cases.
• Keys, TTL & Values — the full rules.
• Recipes — read-through, memoization, rate limiting, and more.
• Configuration Options — every option, every handler.