Implement an basic cache for faces.. Issue #193

lib/Controller/FaceController.php

@@ -17,32 +17,50 @@
 use OCA\FaceRecognition\Db\Image;
 use OCA\FaceRecognition\Db\ImageMapper;
 
+use OCA\FaceRecognition\Service\FileCache;
+
 class FaceController extends Controller {
 
 	private $rootFolder;
 	private $faceMapper;
 	private $imageMapper;
+	private $fileCache;
 	private $userId;
 
 	public function __construct($AppName,
 	                            IRequest    $request,
 	                            IRootFolder $rootFolder,
 	                            FaceMapper  $faceMapper,
 	                            ImageMapper $imageMapper,
+	                            FileCache   $fileCache,
 	                            $UserId)
 	{
 		parent::__construct($AppName, $request);
 		$this->rootFolder = $rootFolder;
 		$this->faceMapper = $faceMapper;
 		$this->imageMapper = $imageMapper;
+		$this->fileCache = $fileCache;
 		$this->userId = $UserId;
 	}
 
 	/**
 	 * @NoAdminRequired
 	 * @NoCSRFRequired
+	 *
+	 * @return DataDisplayResponse
 	 */
-	public function getThumb ($id, $size) {
+	public function getThumb (int $id, int $size) {
+
+		$key = 'face-'. $this->userId . '-' .$id . '-' . $size . 'x' . $size;
+		if ($this->fileCache->hasKey($key)) {
+			$imgData = $this->fileCache->get($key);
+			if (!is_null($imgData)) {
+				$img = new OCP_Image();
+				$img->loadFromData($imgData);
+				return new DataDisplayResponse($img->data(), Http::STATUS_OK, ['Content-Type' => $img->mimeType()]);
+			}
+		}
+
 		$face = $this->faceMapper->find($id);
 		$image = $this->imageMapper->find($this->userId, $face->getImage());
 		$fileId = $image->getFile();
@@ -73,12 +91,10 @@ public function getThumb ($id, $size) {
 		$img->crop($x, $y, $w, $h);
 		$img->scaleDownToFit($size, $size);
 
-		$resp = new DataDisplayResponse($img->data(), Http::STATUS_OK, ['Content-Type' => $img->mimeType()]);
-		$resp->setETag((string)crc32($img->data()));
-		$resp->cacheFor(7 * 24 * 60 * 60);
-		$resp->setLastModified(new \DateTime('now', new \DateTimeZone('GMT')));
+		$this->fileCache->set($key, $img->data());
+
+		return new DataDisplayResponse($img->data(), Http::STATUS_OK, ['Content-Type' => $img->mimeType()]);
 
-		return $resp;
 	}
 
 }

lib/Service/FileCache.php

@@ -0,0 +1,134 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ *
+ * @author Joas Schilling <coding@schilljs.com>
+ * @author Lukas Reschke <lukas@statuscode.ch>
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ * @author Sebastian Wessalowski <sebastian@wessalowski.org>
+ * @author Thomas Müller <thomas.mueller@tmit.eu>
+ * @author Vincent Petry <pvince81@owncloud.com>
+ *
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCA\FaceRecognition\Service;
+
+use OCP\Files\IAppData;
+use OCP\Files\NotFoundException;
+use OCP\Files\NotPermittedException;
+use OCP\ICache;
+
+class FileCache implements ICache {
+
+	const TIMEOUT = 60*60*24*30*2; // two months
+
+	protected $storage;
+
+	public function __construct(IAppData $appData) {
+		try {
+			$this->storage = $appData->getFolder('cache');
+		} catch (NotFoundException $e) {
+			$appData->newFolder('cache');
+			$this->storage = $appData->getFolder('cache');
+		}
+	}
+
+	/**
+	 * @param string $key
+	 * @return mixed|null
+	 * @throws NotFoundException
+	 * @throws NotPermittedException
+	 */
+	public function get($key) {
+		$result = null;
+		if ($this->hasKey($key)) {
+			$result = $this->storage->getFile($key)->getContent();
+		}
+		return $result;
+	}
+
+	/**
+	 * Returns the size of the stored/cached data
+	 *
+	 * @param string $key
+	 * @return int
+	 * @throws NotFoundException
+	 */
+	public function size($key) {
+		$result = 0;
+		if ($this->hasKey($key)) {
+			$result = $this->storage->getFile($key)->getSize();
+		}
+		return $result;
+	}
+
+	/**
+	 * @param string $key
+	 * @param mixed $value
+	 * @param int $ttl
+	 * @return bool|mixed
+	 * @throws NotFoundException
+	 * @throws NotPermittedException
+	 */
+	public function set($key, $value, $ttl = 0) {
+		$file = $this->storage->newFile($key);
+		$file->putContent($value);
+		return true;
+	}
+	/**
+	 * @param string $key
+	 * @return bool
+	 */
+	public function hasKey($key) {
+		if ($this->storage->fileExists($key)) {
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * @param string $key
+	 * @return bool|mixed
+	 * @throws NotFoundException
+	 * @throws NotPermittedException
+	 */
+	public function remove($key) {
+		return $this->storage->getFile($key)->delete();
+	}
+
+	/**
+	 * @param string $prefix
+	 * @return void
+	 * @throws NotPermittedException
+	 */
+	public function clear($prefix = '') {
+		$this->storage->delete();
+	}
+
+	/**
+	 * Runs GC
+	 *
+	 * @throws NotPermittedException
+	 */
+	public function gc() {
+		foreach ($this->storage->getDirectoryListing() as $file) {
+			if (time() - self::TIMEOUT > $file->getMTime()) {
+				$file->delete();
+			}
+		}
+	}
+
+}