* split local cache implementation into a separate class

 * allow custom implementations provided by plugins

1 files changed, 76 insertions, 143 deletions

diff --git a/classes/diskcache.php b/classes/diskcache.php
index 1df8daf15..4cec77cde 100644
--- a/classes/diskcache.php
+++ b/classes/diskcache.php
@@ -1,6 +1,7 @@
 <?php
-class DiskCache {
-	private string $dir;
+class DiskCache implements Cache_Adapter {
+	/** @var Cache_Adapter $adapter */
+	private $adapter;
 
 	/**
 	 * https://stackoverflow.com/a/53662733
@@ -195,60 +196,63 @@ class DiskCache {
 	];
 
 	public function __construct(string $dir) {
-		$this->dir = Config::get(Config::CACHE_DIR) . "/" . basename(clean($dir));
+		foreach (PluginHost::getInstance()->get_plugins() as $n => $p) {
+			if (implements_interface($p, "Cache_Adapter")) {
+
+				/** @var Cache_Adapter $p */
+				$this->adapter = $p;
+				$this->adapter->set_dir($dir);
+				return;
+			}
+		}
+
+		$this->adapter = new Cache_Local();
+		$this->adapter->set_dir($dir);
 	}
 
-	public function get_dir(): string {
-		return $this->dir;
+	public function set_dir(string $dir) : void {
+		$this->adapter->set_dir($dir);
 	}
 
 	public function make_dir(): bool {
-		if (!is_dir($this->dir)) {
-			return mkdir($this->dir);
-		}
-		return false;
+		return $this->adapter->make_dir();
 	}
 
 	public function is_writable(?string $filename = null): bool {
-		if ($filename) {
-			if (file_exists($this->get_full_path($filename)))
-				return is_writable($this->get_full_path($filename));
-			else
-				return is_writable($this->dir);
-		} else {
-			return is_writable($this->dir);
-		}
+		return $this->adapter->is_writable($filename);
 	}
 
 	public function exists(string $filename): bool {
-		return file_exists($this->get_full_path($filename));
+		return $this->adapter->exists($filename);
 	}
 
-	/**
-	 * @return int|false -1 if the file doesn't exist, false if an error occurred, size in bytes otherwise
-	 */
 	public function get_size(string $filename) {
-		if ($this->exists($filename))
-			return filesize($this->get_full_path($filename));
-		else
-			return -1;
-	}
-
-	public function get_full_path(string $filename): string {
-		return $this->dir . "/" . basename(clean($filename));
+		return $this->adapter->get_size($filename);
 	}
 
-	/**
-	 * @param mixed $data
-	 *
-	 * @return int|false Bytes written or false if an error occurred.
-	 */
 	public function put(string $filename, $data) {
-		return file_put_contents($this->get_full_path($filename), $data);
+		return $this->adapter->put($filename, $data);
 	}
 
 	public function touch(string $filename): bool {
-		return touch($this->get_full_path($filename));
+		return $this->adapter->touch($filename);
+	}
+
+	public function get(string $filename): ?string {
+		return $this->adapter->get($filename);
+	}
+
+	static function expire(): void {
+		$adapter = new Cache_Local();
+		$adapter->expire_all();
+	}
+
+	public function expire_all(): void {
+		$this->adapter->expire_all();
+	}
+
+	public function get_dir(): string {
+		return $this->adapter->get_dir();
 	}
 
 	/** Downloads $url to cache as $local_filename if its missing (unless $force-ed)
@@ -271,48 +275,57 @@ class DiskCache {
 		return false;
 	}
 
-	public function get(string $filename): ?string {
-		if ($this->exists($filename))
-			return file_get_contents($this->get_full_path($filename));
-		else
-			return null;
-	}
-
 	/**
-	 * @return false|null|string false if detection failed, null if the file doesn't exist, string mime content type otherwise
+	 * @return bool|int false if the file doesn't exist (or unreadable) or isn't audio/video, true if a plugin handled, otherwise int of bytes sent
 	 */
-	public function get_mime_type(string $filename) {
-		if ($this->exists($filename))
-			return mime_content_type($this->get_full_path($filename));
-		else
-			return null;
-	}
+	public function send(string $filename) {
+		$mimetype = $this->adapter->get_mime_type($filename);
 
-	public function get_fake_extension(string $filename): string {
-		$mimetype = $this->get_mime_type($filename);
+		if ($mimetype == "application/octet-stream")
+				$mimetype = "video/mp4";
 
-		if ($mimetype)
-			return isset($this->mimeMap[$mimetype]) ? $this->mimeMap[$mimetype] : "";
-		else
-			return "";
-	}
+		# block SVG because of possible embedded javascript (.....)
+		$mimetype_blacklist = [ "image/svg+xml" ];
+
+		/* only serve video and images */
+		if (!preg_match("/(image|audio|video)\//", (string)$mimetype) || in_array($mimetype, $mimetype_blacklist)) {
+			http_response_code(400);
+			header("Content-type: text/plain");
+
+			print "Stored file has disallowed content type ($mimetype)";
+			return false;
+		}
 
-	/**
-	 * @return bool|int false if the file doesn't exist (or unreadable) or isn't audio/video, true if a plugin handled, otherwise int of bytes sent
-	 */
-	public function send(string $filename) {
 		$fake_extension = $this->get_fake_extension($filename);
 
 		if ($fake_extension)
 			$fake_extension = ".$fake_extension";
 
 		header("Content-Disposition: inline; filename=\"{$filename}{$fake_extension}\"");
+		header("Content-type: $mimetype");
 
-		return $this->send_local_file($this->get_full_path($filename));
+		return $this->adapter->send($filename);
+	}
+
+	public function get_full_path(string $filename): string {
+		return $this->adapter->get_full_path($filename);
+	}
+
+	public function get_mime_type(string $filename) {
+		return $this->adapter->get_mime_type($filename);
+	}
+
+	public function get_fake_extension(string $filename): string {
+		$mimetype = $this->get_mime_type($filename);
+
+		if ($mimetype)
+			return isset($this->mimeMap[$mimetype]) ? $this->mimeMap[$mimetype] : "";
+		else
+			return "";
 	}
 
 	public function get_url(string $filename): string {
-		return Config::get_self_url() . "/public.php?op=cached&file=" . basename($this->dir) . "/" . basename($filename);
+		return Config::get_self_url() . "/public.php?op=cached&file=" . basename($this->adapter->get_dir()) . "/" . basename($filename);
 	}
 
 	// check for locally cached (media) URLs and rewrite to local versions
@@ -375,84 +388,4 @@ class DiskCache {
 		}
 		return $res;
 	}
-
-	static function expire(): void {
-		$dirs = array_filter(glob(Config::get(Config::CACHE_DIR) . "/*"), "is_dir");
-
-		foreach ($dirs as $cache_dir) {
-			$num_deleted = 0;
-
-			if (is_writable($cache_dir) && !file_exists("$cache_dir/.no-auto-expiry")) {
-				$files = glob("$cache_dir/*");
-
-				if ($files) {
-					foreach ($files as $file) {
-						if (time() - filemtime($file) > 86400*Config::get(Config::CACHE_MAX_DAYS)) {
-							unlink($file);
-
-							++$num_deleted;
-						}
-					}
-				}
-
-				Debug::log("Expired $cache_dir: removed $num_deleted files.");
-			}
-		}
-	}
-
-	/*	 */
-	/**
-	 * this is essentially a wrapper for readfile() which allows plugins to hook
-	 * output with httpd-specific "fast" implementation i.e. X-Sendfile or whatever else
-	 *
-	 * hook function should return true if request was handled (or at least attempted to)
-	 *
-	 * note that this can be called without user context so the plugin to handle this
-	 * should be loaded systemwide in config.php
-	 *
-	 * @return bool|int false if the file doesn't exist (or unreadable) or isn't audio/video, true if a plugin handled, otherwise int of bytes sent
-	 */
-	function send_local_file(string $filename) {
-		if (file_exists($filename)) {
-
-			if (is_writable($filename)) touch($filename);
-
-			$mimetype = mime_content_type($filename);
-
-			// this is hardly ideal but 1) only media is cached in images/ and 2) seemingly only mp4
-			// video files are detected as octet-stream by mime_content_type()
-
-			if ($mimetype == "application/octet-stream")
-				$mimetype = "video/mp4";
-
-			# block SVG because of possible embedded javascript (.....)
-			$mimetype_blacklist = [ "image/svg+xml" ];
-
-			/* only serve video and images */
-			if (!preg_match("/(image|audio|video)\//", (string)$mimetype) || in_array($mimetype, $mimetype_blacklist)) {
-				http_response_code(400);
-				header("Content-type: text/plain");
-
-				print "Stored file has disallowed content type ($mimetype)";
-				return false;
-			}
-
-			$tmppluginhost = new PluginHost();
-
-			$tmppluginhost->load(Config::get(Config::PLUGINS), PluginHost::KIND_SYSTEM);
-			//$tmppluginhost->load_data();
-
-			if ($tmppluginhost->run_hooks_until(PluginHost::HOOK_SEND_LOCAL_FILE, true, $filename))
-				return true;
-
-			header("Content-type: $mimetype");
-
-			$stamp = gmdate("D, d M Y H:i:s", (int)filemtime($filename)) . " GMT";
-			header("Last-Modified: $stamp", true);
-
-			return readfile($filename);
-		} else {
-			return false;
-		}
-	}
 }