docs

CHANGELOG.md

@@ -27,6 +27,7 @@ Examples:
 * [PR #59](https://github.com/SonsOfPHP/sonsofphp/pull/59) Added new HttpMessage component
 * [PR #59](https://github.com/SonsOfPHP/sonsofphp/pull/59) Added new HttpFactory component
 * [PR #70](https://github.com/SonsOfPHP/sonsofphp/pull/70) Added new Core contract
+* [PR #112](https://github.com/SonsOfPHP/sonsofphp/pull/112) [Cache] Added new component
 
 ## [0.3.8]
 

docs/components/cache/index.md

@@ -9,3 +9,58 @@ Used for cache stuff
 ```shell
 composer require sonsofphp/cache
 ```
+
+### PSR-16 - Simple Cache
+
+To add support for PSR-16 Simple Cache, require the PSR.
+
+```shell
+composer require psr/simple-cache
+```
+
+## Usage
+
+```php
+<?php
+
+use SonsOfPHP\Component\Cache\Adapter\ApcuAdapter;
+
+$pool = new ApcuAdapter();
+```
+
+All Adapters implement `Psr\Cache\CacheItemPoolInterface`
+
+### PSR-16 Simple Cache Wrapper
+
+```php
+<?php
+
+use SonsOfPHP\Component\Cache\Adapter\ApcuAdapter;
+use SonsOfPHP\Component\Cache\SimpleCache;
+
+$pool = new ApcuAdapter();
+$cache = new SimpleCache($pool);
+```
+
+`SimpleCache` implements `Psr\SimpleCache\CacheInterface`.
+
+### Setting up a multi layer cache
+
+```php
+<?php
+
+use SonsOfPHP\Component\Cache\Adapter\ArrayAdapter;
+use SonsOfPHP\Component\Cache\Adapter\ApcuAdapter;
+use SonsOfPHP\Component\Cache\Adapter\ChainAdapter;
+
+$pool = new ChainAdapter([
+    new ArrayAdapter(),
+    new ApcuAdapter(),
+]);
+```
+
+The `ChainAdapter` will read from all pools and return the first result it
+finds. So in the above example, if the cache item is not found in
+`ArrayAdapter`, it will look for it in the `ApcuAdapter` pool.
+
+The `ChainAdapter` will also write to and delete from all pools.

src/SonsOfPHP/Component/Cache/Adapter/ChainAdapter.php

@@ -40,7 +40,13 @@ public function __construct(
      */
     public function getItem(string $key): CacheItemInterface
     {
-        return $this->adapters[0]->getItem($key);
+        foreach ($this->adapters as $adapter) {
+            if ($adapter->hasItem($key)) {
+                return $adapter->getItem($key);
+            }
+        }
+
+        return new CacheItem($key, false);
     }
 
     /**