From 1.8 to 1.9

In the examples we are upgrading an imaginary «Photos» plugin.

Only the key changes are included. For example some of the deprecated functions are not mentioned here separately.

Each section will include information whether the change is backwards compatible with Elgg 1.8.

The manifest file

No changes are needed if your plugin is compatible with 1.8.

It’s however recommended to add the <id> tag. It’s value should be the name of the directory where the plugin is located inside the mod/ directory.

If you make changes that break BC, you must update the plugin version and the required Elgg release.

Example of (shortened) old version:

<?xml version="1.0" encoding="UTF-8"?>
<plugin_manifest xmlns="http://www.elgg.org/plugin_manifest/1.8">
    <name>Photos</name>
    <author>John Doe</author>
    <version>1.0</version>
    <description>Adds possibility to upload photos and arrange them into albums.</description>
    <requires>
        <type>elgg_release</type>
        <version>1.8</version>
    </requires>
</plugin_manifest>

Example of (shortened) new version:

<?xml version="1.0" encoding="UTF-8"?>
<plugin_manifest xmlns="http://www.elgg.org/plugin_manifest/1.8">
    <name>Photos</name>
    <id>photos</id>
    <author>John Doe</author>
    <version>2.0</version>
    <description>Adds possibility to upload photos and arrange them into albums.</description>
    <requires>
        <type>elgg_release</type>
        <version>1.9</version>
    </requires>
</plugin_manifest>

$CONFIG and $vars[“config”]

Both the global $CONFIG variable and the $vars['config'] parameter have been deprecated. They should be replaced with the elgg_get_config() function.

Example of old code:

// Using the global $CONFIG variable:
global $CONFIG;
$plugins_path = $CONFIG->plugins_path

// Using the $vars view parameter:
$plugins_path = $vars['plugins_path'];

Example of new code:

$plugins_path = elgg_get_config('plugins_path');

Nota

Compatible with 1.8

Language files

In Elgg 1.8 the language files needed to use the add_translation() function. In 1.9 it is enough to just return the array that was previously passed to the function as a parameter. Elgg core will use the file name (e.g. en.php) to tell which language the file contains.

Example of the old way in languages/en.php:

$english = array(
    'photos:all' => 'All photos',
);
add_translation('en', $english);

Example of new way:

return array(
    'photos:all' => 'All photos',
);

Advertencia

Not compatible with 1.8

Notifications

One of the biggest changes in Elgg 1.9 is the notifications system. The new system allows more flexible and scalable way of sending notifications.

Example of the old way:

function photos_init() {
    // Tell core that we want to send notifications about new photos
    register_notification_object('object', 'photo', elgg_echo('photo:new'));

    // Register a handler that creates the notification message
    elgg_register_plugin_hook_handler('notify:entity:message', 'object', 'photos_notify_message');
}

/**
 * Set the notification message body
 *
 * @param string $hook    Hook name
 * @param string $type    Hook type
 * @param string $message The current message body
 * @param array  $params  Parameters about the photo
 * @return string
 */
function photos_notify_message($hook, $type, $message, $params) {
    $entity = $params['entity'];
    $to_entity = $params['to_entity'];
    $method = $params['method'];
    if (elgg_instanceof($entity, 'object', 'photo')) {
        $descr = $entity->excerpt;
        $title = $entity->title;
        $owner = $entity->getOwnerEntity();
        return elgg_echo('photos:notification', array(
            $owner->name,
            $title,
            $descr,
            $entity->getURL()
        ));
    }
    return null;
}

Example of the new way:

function photos_init() {
    elgg_register_notification_event('object', 'photo', array('create'));
    elgg_register_plugin_hook_handler('prepare', 'notification:publish:object:photo', 'photos_prepare_notification');
}

/**
 * Prepare a notification message about a new photo
 *
 * @param string                          $hook         Hook name
 * @param string                          $type         Hook type
 * @param Elgg_Notifications_Notification $notification The notification to prepare
 * @param array                           $params       Hook parameters
 * @return Elgg_Notifications_Notification
 */
function photos_prepare_notification($hook, $type, $notification, $params) {
    $entity = $params['event']->getObject();
    $owner = $params['event']->getActor();
    $recipient = $params['recipient'];
    $language = $params['language'];
    $method = $params['method'];

    // Title for the notification
    $notification->subject = elgg_echo('photos:notify:subject', array($entity->title), $language);

    // Message body for the notification
    $notification->body = elgg_echo('photos:notify:body', array(
        $owner->name,
        $entity->title,
        $entity->getExcerpt(),
        $entity->getURL()
    ), $language);

    // The summary text is used e.g. by the site_notifications plugin
    $notification->summary = elgg_echo('photos:notify:summary', array($entity->title), $language);

    return $notification;
}

Advertencia

Not compatible with 1.8

Nota

See how the community_plugins plugin was updated to use the new system: https://github.com/Elgg/community_plugins/commit/bfa356cfe8fb99ebbca4109a1b8a1383b70ff123

Notifications can also be sent with the notify_user() function.

It has however been updated to support three new optional parameters passed inside an array as the fifth parameter.

The parameters give notification plugins more control over the notifications, so they should be included whenever possible. For example the bundled site_notifications plugin won’t work properly if the parameters are missing.

Parameters:

  • object The object that we are notifying about (e.g. ElggEntity or ElggAnnotation). This is needed so that notification plugins can provide a link to the object.
  • action String that describes the action that triggered the notification (e.g. «create», «update», etc).
  • summary String that contains a summary of the notification. (It should be more informative than the notification subject but less informative than the notification body.)

Example of the old way:

// Notify $owner that $user has added a $rating to an $entity created by him

$subject = elgg_echo('rating:notify:subject');
$body = elgg_echo('rating:notify:body', array(
        $owner->name,
        $user->name,
        $entity->title,
        $entity->getURL(),
));

notify_user($owner->guid,
                        $user->guid,
                        $subject,
                        $body
                );

Example of the new way:

// Notify $owner that $user has added a $rating to an $entity created by him

$subject = elgg_echo('rating:notify:subject');
$summary = elgg_echo('rating:notify:summary', array($entity->title));
$body = elgg_echo('rating:notify:body', array(
        $owner->name,
        $user->name,
        $entity->title,
        $entity->getURL(),
));

$params = array(
        'object' => $rating,
        'action' => 'create',
        'summary' => $summary,
);

notify_user($owner->guid,
                        $user->guid,
                        $subject,
                        $body,
                        $params
                );

Nota

Compatible with 1.8

Adding items to the Activity listing

add_to_river('river/object/photo/create', 'create', $user_guid, $photo_guid);
elgg_create_river_item(array(
    'view' => 'river/object/photo/create',
    'action_type' => 'create',
    'subject_guid' => $user_guid,
    'object_guid' => $photo_guid,
));

You can also add the optional target_guid parameter which tells the target of the create action.

If the photo would had been added for example into a photo album, we could add it by passing in also:

'target_guid' => $album_guid,

Advertencia

Not compatible with 1.8

Entity URL handlers

The elgg_register_entity_url_handler() function has been deprecated. In 1.9 you should use the 'entity:url', 'object' plugin hook instead.

Example of the old way:

/**
 * Initialize the photo plugin
 */
my_plugin_init() {
    elgg_register_entity_url_handler('object', 'photo', 'photo_url_handler');
}

/**
 * Returns the URL from a photo entity
 *
 * @param ElggEntity $entity
 * @return string
 */
function photo_url_handler($entity) {
    return "photo/view/{$entity->guid}";
}

Example of the new way:

/**
 * Initialize the photo plugin
 */
my_plugin_init() {
    elgg_register_plugin_hook_handler('entity:url', 'object', 'photo_url_handler');
}

/**
 * Returns the URL from a photo entity
 *
 * @param string $hook   'entity:url'
 * @param string $type   'object'
 * @param string $url    The current URL
 * @param array  $params Hook parameters
 * @return string
 */
function photo_url_handler($hook, $type, $url, $params) {
    $entity = $params['entity'];

    // Check that the entity is a photo object
    if ($entity->getSubtype() !== 'photo') {
        // This is not a photo object, so there's no need to go further
        return;
    }

    return "photo/view/{$entity->guid}";
}

Advertencia

Not compatible with 1.8

Web services

In Elgg 1.8 the web services API was included in core and methods were exposed using expose_function(). To enable the same functionality for Elgg 1.9, enable the «Web services 1.9» plugin and replace all calls to expose_function() with elgg_ws_expose_function().