Changing Album Thumbnail

Hi,

I would like to have G2 automatically detect if there's a filename named '_category_image.jpg' in an album folder, and if so, use that to show as the album's thumbnail.

Is this possible? If so, where in the code should I look to make this modification?

Thanks,
Ralph

Unfortunately not, because each of my albums already has a _category_image.jpg and I need to be able to set up albums in the fastest way possible, since many are batch uploaded every day. Any help will be really appreciated. Thanks, Ralph.

Thanks for the reply. I'll look into submitting the request at SourceForge. However, I would also be interested in coding this myself, but can't seem to find exactly what script/s I should edit. Any guidance will be appreciated. Thanks, Ralph.

Ok, I would be interested in writing a module for this, as well as for other features in the future. Although I know PHP, I'm finding it quite hard to understand the overall functioning of the system and how I should approach this. Some guidance might help me get on the right path. Thanks, Ralph.

ralphch, first i'd write down the user story.
how is it supposed to work?
1. bob creates a new album A
2. bob adds an item called _category_image.jpg to A
3. G2 detects that it should use A as the album highlight for A

correct?

So what you need is a G2 module that listens for GalleryEntity::save events and checks whether the entity's storage flag is newly created and check what type of Entity it is (you want GalleryPhotoItem or something like that) and if it's name is the same is the name for default album highlights.
If all these if conditions apply in your handleEvent function, then you get the parent item (the album) of the newly created item and assign the new item as the highlight of the parent.

you can look at other modules (module.inc) on how to listen for events and how to handle them.

Here's how I've started the functionality section of my module.inc file:

/**
* @see GalleryEntity_core::onSave
*/

function onSave() {

list($ret, $itemtype) = GalleryEntity::getentityType();
if ($ret->isError()) {
return array($ret->wrap(__FILE__, __LINE__), null);
}

}

Is this correct? I'm quite lost since I've read the documentation but it's incomplete and I can't seem to find any information on how to use each of these objects.

Thanks for the reply. Ok, so here's what I'm doing:

In module.inc

/**
* @see GalleryModule::registerEventListeners()
*/

function registerEventListeners() {

GalleryCoreApi::requireOnce(dirname(__FILE__) . '/classes/SetAlbumThumbnail.class');
$listener = new SetAlbumThumbnail();
GalleryCoreApi::registerEventListener('GalleryEntity::save',$listener,true);

}

And then in SetAlbumThumbnail.class:

class SetAlbumThumbnail /* extends GalleryEventListener */ {

/**
* @see GalleryEventListener::handleEvent
*/

function handleEvent($event) {

switch($event->getEventName()) {
case 'GalleryEntity::save':

// do all the stuff.

}

}


}

However, I don't understand where and how I can check to see if the filaneme is '_category_image.jpg' and, if so, upload it to the album's folder and set it as the album's thumbnail (shouldn't this be written to a mysql table or something?).

Also, what would happen if the user uploads the _category_image.jpg file through FTP? Then none of this would work. So can't I implement a module that adds functionality to the front-end display of thumbnails? Such that before displaying a thumbnail, it checks if the item is an album and if so, looks for '_category_image.jpg'. Otherwise, it defaults to normal functionality.

Here's the code, I followed the API documentation, but nothing works.

module.inc

<?php
/*
* $RCSfile: module.inc,v $
*
* Gallery - a web based photo album viewer and editor
* Copyright (C) 2000-2005 Bharat Mediratta
*
* This program 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 2 of the License, or (at
* your option) any later version.
*
* 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
USA.
*/
/**
* @package albumthumb
* @version $Revision: 1.63 $ $Date: 2005/06/20 21:00:00 $
* @author Ralph
*/

/**
* Album Thumbnail module
*
* @package albumthumb
*/
class AlbumThumbModule extends GalleryModule {

    function AlbumThumbModule() {
    global $gallery;

    $this->setId('albumthumb');
    $this->setName('Album Thumbnail');
    $this->setDescription($gallery->i18n('Detects the thumbnail for an album'));
    $this->setVersion('0.9.0');
    $this->setGroup('data', $this->translate('Extra Data'));
    $this->setCallbacks('');
    $this->setRequiredCoreApi(array(5, 8));
    $this->setRequiredModuleApi(array(0, 9));
    }

    /**
     * @see GalleryModule::autoConfigure
     */
    function autoConfigure() {
    /* We don't require any special configuration */
    return array(GalleryStatus::success(), true);
    }

/**
* @see GalleryModule::registerEventListeners()
*/

function registerEventListeners() {

GalleryCoreApi::requireOnce(dirname(__FILE__) . '/classes/SetAlbumThumbnail.class');
$listener = new SetAlbumThumbnail();
GalleryCoreApi::registerEventListener('GalleryEntity::save',$listener,true);

}

}

?>

SetAlbumThumbnail.class

<?php

/*
 * $RCSfile: SetAlbumThumbnail.class,v $
 *
 * Gallery - a web based photo album viewer and editor
 * Copyright (C) 2000-2005 Bharat Mediratta
 *
 * This program 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 2 of the License, or (at
 * your option) any later version.
 *
 * 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
/**
 * @version $Revision: 1.36 $ $Date: 2005/06/20 21:00:00 $
 * @package albumthumb
 * @author Ralph
 */

/**
 * A helper class for the AlbumThumb module.
 *
 * @package albumthumb
 * @subpackage Classes
 */

class SetAlbumThumbnail /* extends GalleryEventListener */ {

/**
* @see GalleryEventListener::handleEvent
*/

function handleEvent($event) {

switch($event->getEventName()) {
case 'GalleryEntity::save':
if($event->_pathComponent == '_category_image.jpg') { $event->setserialNumber(4); }
}

}

}

?>

Am I missing something here? Any help will be appreciated.

Thanks,
Ralph[/code]

I just added echo $gallery->debug($debugMsg) but nothing shows up. Is this code correct or am I doing it all incorrectly (this is what it seems like)?

Thanks,
Ralph

Ok thanks, I just enabled the Debug module and added the following to my eventHandle($event) function in SetAlbumThumbnail.class

global $gallery;
$gallery->debug('The filename is' . $event->_pathComponent);

Whenever I upload a file using the Add Item interface on the front-end, this debug message doesn't show up anywhere on the page. My best guess is that I'm going wrong about this whole thing and the handleEvent function isn't even being called whenever I upload a new item.

I set config.php to debug mode ($gallery->setDebug('buffered')) and it's still not showing the debug msg I'm sending from SetAlbumThumbnail.class. So this module is clearly not working, not even being called whenever a new item is added. Any ideas?

Thanks,
Ralph

Yeah, I installed and activated it, but it doesn't work.

valiant thanks for the help. Even when debugging there's no indication that the module is being loaded when an item is saved. Therefore, I recoded the whole thing into the following:

module.inc

class AlbumThumbModule extends GalleryModule {

    function AlbumThumbModule() {
    global $gallery;

    $this->setId('albumthumb');
    $this->setName('Album Thumbnail');
    $this->setDescription($gallery->i18n('Detects the thumbnail for an album'));
    $this->setVersion('0.9.0');
    $this->setGroup('data', $this->translate('Extra Data'));
    $this->setCallbacks('');
    $this->setRequiredCoreApi(array(5, 8));
    $this->setRequiredModuleApi(array(0, 9));
    }

/*
* @see GalleryModule::performFactoryRegistrations()
*/

function performFactoryRegistrations() {

	$ret = GalleryCoreApi::registerFactoryImplementation('ItemAddOption',
	    'SetAlbumThumbnail', 'SetAlbumThumbnail',
	    'modules/albumthumb/SetAlbumThumbnail.inc', 'albumthumb', null);
	if ($ret->isError()) {
	    return $ret->wrap(__FILE__, __LINE__);
	}

	return GalleryStatus::success();

}

    /**
     * @see GalleryModule::autoConfigure
     */
    function autoConfigure() {
    /* We don't require any special configuration */
    return array(GalleryStatus::success(), true);
    }

}

SetAlbumThumbnail.inc

class SetAlbumThumbnail extends ItemAddOption {

/*
* @see ItemAddOption::isAppropriate
*/

function isAppropriate() {
return array(GalleryStatus::success(), true);
}

/*
* @see ItemAddOption::handleRequestAfterAdd
*/

function handleRequestAfterAdd($form, $items) {
global $gallery;

$errors = array();
$warnings = array();

$itemIds = array();

foreach ($items as $item) {
$itemIds[] = $item->getId();
}

list ($ret, $lockId) = GalleryCoreApi::acquireWriteLock($itemIds);
if ($ret->isError()) {
return array($ret->wrap(__FILE__, __LINE__), null, null);
}

for ($i = 0; $i < count($items); $i++) {

$warnings[$i] = array();
$itemId = $items[$i]->getId();

$mustSave = false;
$items[$i]->setSummary('Test summary'); // REPLACE THIS FOR DETECT ALBUM THUMBNAIL CODE AND SET AS HIGHLIGHT
$mustSave = true;

$gallery->debug('The items filename is ' . $items[$i]->getFilename());

	    if ($mustSave) {
		$ret = $items[$i]->save();
		if ($ret->isError()) {
		    GalleryCoreApi::releaseLocks($lockId);
		    return array($ret->wrap(__FILE__, __LINE__), null, null);
		}
	}

}

$ret = GalleryCoreApi::releaseLocks($lockId);
if($ret->isError()) {
return array($ret->wrap(__FILE__,__LINE__), null, null);
}

return array(GalleryStatus::success(), $errors, $warnings);

}

}

Is this approach correct? Now the module is loaded whenever I add a new item but whenever saving a new item the following error displays:

Your change cannot be completed because somebody else has made a conflicting change to the same item. Use the back button in your browser to go back to the page you were on, then reload that page and try your change again.
Go back and try again

Alternatively, you can return to the main Gallery page and resume browsing.

Back to the Gallery
Error Detail -
Error (ERROR_OBSOLETE_DATA) : UPDATE g2_Entity SET g_modificationTimestamp=?,g_serialNumber=? WHERE g_id=? AND g_serialNumber=? (1119388590|2|459|1)

    * in modules/core/classes/GalleryStorage/DatabaseStorage.class at line 586 (gallerystatus::error)
    * in modules/core/classes/GalleryStorage.class at line 133 (mysqldatabasestorage::saveentity)
    * in modules/core/classes/GalleryEntity.class at line 293 (gallerystorage::saveentity)
    * in modules/core/classes/GalleryItem.class at line 409 (galleryfilesystementity::save)
    * in modules/albumthumb/SetAlbumThumbnail.inc at line 81 (galleryphotoitem::save)
    * in modules/core/ItemAdd.inc at line 142 (setalbumthumbnail::handlerequestafteradd)
    * in main.php at line 182 (itemaddcontroller::handlerequest)
    * in main.php at line 86
    * in main.php at line 77

And the summary doesn't get set to the new item. Ideally, this should be setting the 'Test summary' to all new items, right? I'm just doing this to test the functionality of the module, but would later like to change that so that it checks the item's filename, and if it matches '_category_thumbnail.jpg', then sets it as the parent's (album's) highlight. Any ideas will be appreciated.

Thanks,
Ralph

Thanks for the reply. I've checked the code for typos, but there's none, so the issue must be somewhere else. I'm comparing it to the functionality of the Exif module. Any other ideas on why this error is showing up? setSummary doesn't go through (I tried $items[$i]->refresh() but it still doesn't work). Also, do you know where I can find the specific documentation on how to read the filename and highlight it?

Thanks again,
Ralph

I've tried debugging the whole thing, and nothing appears as an error; I also cleared all cache, and it's still got the same error. I'm doing exactly the same operation as the Exif module, and still mine fails. I've also looked at the GalleryItem.class line where it then fails:

/* Save myself */
$ret = parent::save();
if($ret->isError()) {
return $ret->wrap(__FILE__,__LINE__);
}

But can't understand what this 'Save myself' means. I'm lost as to where to look in the code. I've read the documentation and, according to that, I'm locking and refreshing items correctly before saving.

Thanks,
Ralph

i wonder if some other module's ItemAddOption saves the item and doesn't refresh it, so when you get it the $items list has out-of-date items.. try deactivating exif module and trying again, or do list ($ret, $item) = $item->refresh() before changing each item.

1. acquirewritelocks
2. refresh
3. setitemsummary
4. save
5. releaselocks

implement this code, it *should* work.
if it doesn't please post the code and make sure the error you get is in the save call (take a look at the line numbers of the stack trace)

ah, i found the bug, but it's in your code ;)

foreach ($items as $item) {
list($ret,$item) = $item->refresh();
if($ret->isError()) {
return array($ret->wrap(__FILE__,__LINE__));
}

here, you work with copies of the items.
the items in $items are still obsolete.

fix: do the refresh in the main loop:
- and don't forget to release the locks! the exif module does the stuff with releasing the locks not that good. you should release them whenever you have acquired locks and before any return statement.
- and have always the same number of return values. e.g. array(GalleryStatus::success(), null, null) in this case, you shouldn't return one time an array of 3 entries and then an array of 1 entry
- $mustSave is not necessary. $items[$i]->save() does the same logic internally

for ($i = 0; $i < count($items); $i++) {
list($ret,$items[$i]) = $items[$i]->refresh();
if($ret->isError()) {
GalleryCoreApi::releaseLocks($lockId);
return array($ret->wrap(__FILE__,__LINE__), null, null);
}

$warnings[$i] = array();
$itemId = $items[$i]->getId();

$testsummary = "This is a test summary";

// REPLACE FOR MAKE HIGHLIGHT CODE.

$items[$i]->setSummary($testsummary);

      $ret = $items[$i]->save();
      if ($ret->isError()) {
          GalleryCoreApi::releaseLocks($lockId);
          return array($ret->wrap(__FILE__, __LINE__), null, null);
      }
} 

sorry, don't have time to assist you in every step.

ERROR_BAD_PARAMETER -> obviously you don't use a function properly, it expects other parameters. we have documented every function with
@param ...
@param ...
@return ...

so it should be clear what parameters it expects.
if you think you're using the correct parameters, do a var_dump(...); exit; for the variable you're passing to verify that you're doing the correct thing.

there's a html version of the API documentation in the dev documents.
http://gallery.menalto.com/modules/GalleryAPI/apidoc/

Hi, just wondering if there's a function so that once I set the album thumbnail, I can set its permissions so that it can only be viewed, in the album, by the Site Administrator group. I haven't found any function in the API that works in the way of: removeAllItemPermissions except for Site Administrators. Any ideas will be appreciated.

Thanks,
Ralph

valiant thanks a lot for the help! The module's finished; I've posted it in the G2 General Development forum.

Regards,
Ralph