Add new FileCache class

system/src/Grav/Framework/Cache/Adapter/FileCache.php

@@ -0,0 +1,167 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2014 - 2017 RocketTheme, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Grav\Framework\Cache\AbstractCache;
+use Grav\Framework\Cache\Exception\CacheException;
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using file backend.
+ *
+ * @package Grav\Framework\Cache
+ */
+class FileCache extends AbstractCache
+{
+    private $directory;
+    private $tmp;
+
+    public function doGet($key, $miss)
+    {
+        $now = time();
+        $file = $this->getFile($key);
+
+        if (!file_exists($file) || !$h = @fopen($file, 'rb')) {
+            return $miss;
+        }
+
+        if ($now >= (int) $expiresAt = fgets($h)) {
+            fclose($h);
+            @unlink($file);
+        } else {
+            $i = rawurldecode(rtrim(fgets($h)));
+            $value = stream_get_contents($h);
+            fclose($h);
+
+            if ($i === $key) {
+                return unserialize($value);
+            }
+        }
+
+        return $miss;
+    }
+
+    public function doSet($key, $value, $ttl)
+    {
+        $expiresAt = time() + ($ttl ?: 31557600); // = 1 year
+
+        $result = $this->write(
+            $this->getFile($key, true),
+            $expiresAt . "\n" . rawurlencode($key) . "\n" . serialize($value),
+            $expiresAt
+        );
+
+        if (!$result && !is_writable($this->directory)) {
+            throw new CacheException(sprintf('Cache directory is not writable (%s)', $this->directory));
+        }
+
+        return $result;
+    }
+
+    public function doDelete($key)
+    {
+        $file = $this->getFile($key);
+
+        return (!file_exists($file) || @unlink($file) || !file_exists($file));
+    }
+
+    public function doClear()
+    {
+        $result = true;
+        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($this->directory, \FilesystemIterator::SKIP_DOTS));
+
+        foreach ($iterator as $file) {
+            $result = ($file->isDir() || @unlink($file) || !file_exists($file)) && $result;
+        }
+
+        return $result;
+    }
+
+    public function doHas($key)
+    {
+        $file = $this->getFile($key);
+
+        return file_exists($file) && (@filemtime($file) > time() || $this->doGet($key, null));
+    }
+
+    protected function getFile($key, $mkdir = false)
+    {
+        $hash = str_replace('/', '-', base64_encode(hash('sha256', static::class . $key, true)));
+        $dir = $this->directory . $hash[0] . DIRECTORY_SEPARATOR . $hash[1] . DIRECTORY_SEPARATOR;
+
+        if ($mkdir && !file_exists($dir)) {
+            @mkdir($dir, 0777, true);
+        }
+
+        return $dir . substr($hash, 2, 20);
+    }
+
+    private function init($namespace, $directory)
+    {
+        if (!isset($directory[0])) {
+            $directory = sys_get_temp_dir() . '/grav-cache';
+        } else {
+            $directory = realpath($directory) ?: $directory;
+        }
+
+        if (isset($namespace[0])) {
+            if (preg_match('#[^-+_.A-Za-z0-9]#', $namespace, $match)) {
+                throw new InvalidArgumentException(sprintf('Namespace contains "%s" but only characters in [-+_.A-Za-z0-9] are allowed.', $match[0]));
+            }
+            $directory .= DIRECTORY_SEPARATOR . $namespace;
+        }
+
+        if (!file_exists($directory)) {
+            @mkdir($directory, 0777, true);
+        }
+
+        $directory .= DIRECTORY_SEPARATOR;
+        // On Windows the whole path is limited to 258 chars
+        if ('\\' === DIRECTORY_SEPARATOR && strlen($directory) > 234) {
+            throw new InvalidArgumentException(sprintf('Cache folder is too long (%s)', $directory));
+        }
+        $this->directory = $directory;
+    }
+
+    private function write($file, $data, $expiresAt = null)
+    {
+        set_error_handler(__CLASS__.'::throwError');
+
+        try {
+            if ($this->tmp === null) {
+                $this->tmp = $this->directory . uniqid('', true);
+            }
+
+            file_put_contents($this->tmp, $data);
+
+            if ($expiresAt !== null) {
+                touch($this->tmp, $expiresAt);
+            }
+
+            return rename($this->tmp, $file);
+        } finally {
+            restore_error_handler();
+        }
+    }
+
+    /**
+     * @internal
+     */
+    public static function throwError($type, $message, $file, $line)
+    {
+        throw new \ErrorException($message, 0, $type, $file, $line);
+    }
+
+    public function __destruct()
+    {
+        if ($this->tmp !== null && file_exists($this->tmp)) {
+            unlink($this->tmp);
+        }
+    }
+}