Extension:EventBus

MediaWiki extensions manual

EventBus Release status: beta
Implementation	Data extraction
Description	Propagation of change events to a RESTful service
Author(s)	EEvans (WMF)talk
Latest version	0.1 (2015-11-19)
MediaWiki	1.27+
PHP	5.4+
Database changes	No
License	GNU General Public License 2.0 or later
Download	Download extension Git [?]: Download Git master browse repository (GitHub) commit history code review
Hooks used PageContentSaveComplete ArticleDeleteComplete ArticleUndelete PageContentInsertComplete TitleMoveComplete ArticleRevisionVisibilitySet RevisionInsertComplete ArticlePurge BlockIpComplete LinksUpdateComplete ArticleProtectComplete ChangeTagsAfterUpdateTags
Translate the EventBus extension if it is available at translatewiki.net
Check usage and version matrix.
Issues	Open tasks · Report a bug

The EventBus extension propagates state changes (edit, move, delete, revision visibility, etc) to a RESTful event service, providing consumers of the service with the means of tracking changes to MediaWiki content.

Known Issues

Ideally, this sort of change propagation would be atomic, that is to say, if one of the tracked changes is committed in MediaWiki, the corresponding event is guaranteed to be delivered (even if by eventual consistency). As this extension is hook-based, that is not currently the case; Truly reliable event delivery will likely require something bound to the corresponding database transaction. (tracked in task T120242.)

Download / Install

The extension can be retrieved directly from Git ^[?]:

• Browse code
• Some extensions have tags for stable releases.
  • Browse tags
  • Select the tag
  • Click "snapshot"
• Each branch is associated with a past MediaWiki release. There is also a "master" branch containing the latest alpha version (might require an alpha version of MediaWiki).
  • Browse branches
  • Select a branch name
  • Click "Continue"

Extract the snapshot and place it in the extensions/EventBus/ directory of your MediaWiki installation.

If you are familiar with git and have shell access to your server, you can also obtain the extension as follows:

cd extensions/
git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/EventBus.git

• To enable, add the following code to the bottom of your LocalSettings.php:

wfLoadExtension( 'EventBus' );

•  Done; Navigate to 'Special:Version' on your wiki, and verify the extension is successfully installed

Configuration

Note: For this extension to be useful, you need to be running an event service.

To configure the event service, add the following to your LocalSettings.php, (setting the event service name and URL value according to your environment.

$wgEventServices = [
    'eventbus'  => ['url' => 'http://hostname:8888/v1/events', 'timeout' => 10],
    'eventgate' => ['url' => 'http://hostname:8192/v1/events'],
    // ...
];

References

• T84923: Reliable publish / subscribe event bus
• T116786: Integrate eventbus-based event production into MediaWiki
• T120242: Reliable (atomic) MediaWiki event production