Merge branch 'MDL-32471-thumbnails' of git://github.com/mudrd8mz/moodle

blocks/html/lib.php

@@ -28,9 +28,10 @@
  * @param string $filearea file area
  * @param array $args extra arguments
  * @param bool $forcedownload whether or not force download
+ * @param array $options additional options affecting the file serving
  * @return bool
  */
-function block_html_pluginfile($course, $birecord_or_cm, $context, $filearea, $args, $forcedownload) {
+function block_html_pluginfile($course, $birecord_or_cm, $context, $filearea, $args, $forcedownload, array $options=array()) {
     global $SCRIPT;
 
     if ($context->contextlevel != CONTEXT_BLOCK) {
@@ -64,7 +65,7 @@ function block_html_pluginfile($course, $birecord_or_cm, $context, $filearea, $a
     }
 
     session_get_instance()->write_close();
-    send_stored_file($file, 60*60, 0, $forcedownload);
+    send_stored_file($file, 60*60, 0, $forcedownload, $options);
 }
 
 /**

blocks/upgrade.txt

@@ -1,6 +1,12 @@
 This files describes API changes in /blocks/* - activity modules,
 information provided here is intended especially for developers.
 
+=== 2.3 ===
+
+required changes in code:
+* block_xxx_pluginfile() is now given the 7th parameter (hopefully the last one) that
+  contains additional options for the file serving. The array should be re-passed
+  to send_stored_file().
 
 === 2.0 ===
 

lib/filestorage/file_storage.php

@@ -152,6 +152,113 @@ public function get_file_instance(stdClass $file_record) {
         return new stored_file($this, $file_record, $this->filedir);
     }
 
+    /**
+     * Returns an image file that represent the given stored file as a preview
+     *
+     * At the moment, only GIF, JPEG and PNG files are supported to have previews. In the
+     * future, the support for other mimetypes can be added, too (eg. generate an image
+     * preview of PDF, text documents etc).
+     *
+     * @param stored_file $file the file we want to preview
+     * @param string $mode preview mode, eg. 'thumb'
+     * @return stored_file|bool false if unable to create the preview, stored file otherwise
+     */
+    public function get_file_preview(stored_file $file, $mode) {
+
+        $context = context_system::instance();
+        $path = '/' . trim($mode, '/') . '/';
+        $preview = $this->get_file($context->id, 'core', 'preview', 0, $path, $file->get_contenthash());
+
+        if (!$preview) {
+            $preview = $this->create_file_preview($file, $mode);
+            if (!$preview) {
+                return false;
+            }
+        }
+
+        return $preview;
+    }
+
+    /**
+     * Generates a preview image for the stored file
+     *
+     * @param stored_file $file the file we want to preview
+     * @param string $mode preview mode, eg. 'thumb'
+     * @return stored_file|bool the newly created preview file or false
+     */
+    protected function create_file_preview(stored_file $file, $mode) {
+
+        $mimetype = $file->get_mimetype();
+
+        if ($mimetype === 'image/gif' or $mimetype === 'image/jpeg' or $mimetype === 'image/png') {
+            // make a preview of the image
+            $data = $this->create_imagefile_preview($file, $mode);
+
+        } else {
+            // unable to create the preview of this mimetype yet
+            return false;
+        }
+
+        if (empty($data)) {
+            return false;
+        }
+
+        // getimagesizefromstring() is available from PHP 5.4 but we need to support
+        // lower versions, so...
+        $tmproot = make_temp_directory('thumbnails');
+        $tmpfilepath = $tmproot.'/'.$file->get_contenthash().'_'.$mode;
+        file_put_contents($tmpfilepath, $data);
+        $imageinfo = getimagesize($tmpfilepath);
+        unlink($tmpfilepath);
+
+        $context = context_system::instance();
+
+        $record = array(
+            'contextid' => $context->id,
+            'component' => 'core',
+            'filearea'  => 'preview',
+            'itemid'    => 0,
+            'filepath'  => '/' . trim($mode, '/') . '/',
+            'filename'  => $file->get_contenthash(),
+        );
+
+        if ($imageinfo) {
+            $record['mimetype'] = $imageinfo['mime'];
+        }
+
+        return $this->create_file_from_string($record, $data);
+    }
+
+    /**
+     * Generates a preview for the stored image file
+     *
+     * @param stored_file $file the image we want to preview
+     * @param string $mode preview mode, eg. 'thumb'
+     * @return string|bool false if a problem occurs, the thumbnail image data otherwise
+     */
+    protected function create_imagefile_preview(stored_file $file, $mode) {
+        global $CFG;
+        require_once($CFG->libdir.'/gdlib.php');
+
+        $tmproot = make_temp_directory('thumbnails');
+        $tmpfilepath = $tmproot.'/'.$file->get_contenthash();
+        $file->copy_content_to($tmpfilepath);
+
+        if ($mode === 'tinyicon') {
+            $data = generate_image_thumbnail($tmpfilepath, 16, 16);
+
+        } else if ($mode === 'thumb') {
+            $data = generate_image_thumbnail($tmpfilepath, 90, 90);
+
+        } else {
+            throw new file_exception('storedfileproblem', 'Invalid preview mode requested');
+        }
+
+        unlink($tmpfilepath);
+
+        return $data;
+    }
+
     /**
      * Fetch file using local file id.
      *
@@ -1306,6 +1413,25 @@ public function cron() {
         $rs->close();
         mtrace('done.');
 
+        // remove orphaned preview files (that is files in the core preview filearea without
+        // the existing original file)
+        mtrace('Deleting orphaned preview files... ', '');
+        $sql = "SELECT p.*
+                  FROM {files} p
+             LEFT JOIN {files} o ON (p.filename = o.contenthash)
+                 WHERE p.contextid = ? AND p.component = 'core' AND p.filearea = 'preview' AND p.itemid = 0
+                       AND o.id IS NULL";
+        $syscontext = context_system::instance();
+        $rs = $DB->get_recordset_sql($sql, array($syscontext->id));
+        foreach ($rs as $orphan) {
+            $file = $this->get_file_instance($orphan);
+            if (!$file->is_directory()) {
+                $file->delete();
+            }
+        }
+        $rs->close();
+        mtrace('done.');
+
         // remove trash pool files once a day
         // if you want to disable purging of trash put $CFG->fileslastcleanup=time(); into config.php
         if (empty($CFG->fileslastcleanup) or $CFG->fileslastcleanup < time() - 60*60*24) {

lib/filestorage/tests/file_storage_test.php

@@ -0,0 +1,80 @@
+<?php
+
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Unit tests for /lib/filestorage/file_storage.php
+ *
+ * @package   core
+ * @category  test
+ * @copyright 2012 David Mudrak <[email protected]>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->libdir . '/filelib.php');
+
+class filestoragelib_testcase extends advanced_testcase {
+
+    /**
+     * Local files can be added to the filepool
+     */
+    public function test_create_file_from_pathname() {
+        global $CFG;
+
+        $this->resetAfterTest(false);
+
+        $filepath = $CFG->dirroot.'/lib/filestorage/tests/fixtures/testimage.jpg';
+        $syscontext = context_system::instance();
+        $filerecord = array(
+            'contextid' => $syscontext->id,
+            'component' => 'core',
+            'filearea'  => 'unittest',
+            'itemid'    => 0,
+            'filepath'  => '/images/',
+            'filename'  => 'testimage.jpg',
+        );
+
+        $fs = get_file_storage();
+        $fs->create_file_from_pathname($filerecord, $filepath);
+
+        $this->assertTrue($fs->file_exists($syscontext->id, 'core', 'unittest', 0, '/images/', 'testimage.jpg'));
+
+        return $fs->get_file($syscontext->id, 'core', 'unittest', 0, '/images/', 'testimage.jpg');
+    }
+
+    /**
+     * Local images can be added to the filepool and their preview can be obtained
+     *
+     * @depends test_create_file_from_pathname
+     */
+    public function test_get_file_preview(stored_file $file) {
+        global $CFG;
+
+        $this->resetAfterTest(true);
+        $fs = get_file_storage();
+
+        $previewtinyicon = $fs->get_file_preview($file, 'tinyicon');
+        $this->assertInstanceOf('stored_file', $previewtinyicon);
+        $this->assertEquals('6b9864ae1536a8eeef54e097319175a8be12f07c', $previewtinyicon->get_filename());
+
+        $previewtinyicon = $fs->get_file_preview($file, 'thumb');
+        $this->assertInstanceOf('stored_file', $previewtinyicon);
+        $this->assertEquals('6b9864ae1536a8eeef54e097319175a8be12f07c', $previewtinyicon->get_filename());
+    }
+}