Help:Extension:EventStreamConfig

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This EventStreamConfig extension provides library functions and an API endpoint for exporting event stream configuration from the $wgEventStreams MediaWiki configuration variable.

This allows for centralized configuration of streams for both MediaWiki and external uses.

  • The EventLogging extension uses this with ResourceLoader to load configs for streams used on certain pages to dynamically configure client stream settings, like sample rate.
  • Mobile apps use the API endpoint to dynamically configure client stream settings like sample rate.
  • EventGate event intake service(s) use this to ensure that only events of a specific schema title are allowed into a stream.
  • EventBus and other server side event producers uses this to figure out which event intake service a given stream should be produced to.

Usage[edit]

MediaWiki Config[edit]

$wgEventStreams is a list of individual stream configs. Each stream config must minimally specify its schema_title and its stream name settings. In $wgEventStreams, stream may either be a static stream name string, or a regex that matches stream names for which the stream config should be used.

Example:

$wgEventStreams = [
    'test.event' => [
        'stream' => 'test.event',
        'schema_title' => 'test/event',
        'sample_rate' => 0.15,
    ],
    'nonya' => [
        'stream' => 'nonya',
        'schema_title' => 'mediawiki/nonya',
        'sample_rate' => 0.5,
    ],
    'mediawiki.virtual_page_view' => [
        'stream' => 'mediawiki.virtual_page_view',
        'schema_title' => 'mediawiki/page/virtual-view',
        'sample_rate' => 0.1,
    ],
    '/^mediawiki.edit(\..+)?/' => [
        'stream' => '/^mediawiki.edit(\..+)?/',
        'schema_title' => 'mediawiki/edit',
        'sample_rate' => 0.8,
    ],
];

(Note: sample_rate is just an example setting)

Getting configs for a list of streams[edit]

StreamConfigs#get takes a list of stream names to return configs for. $wgEventStreams is keyed by stream name or stream regex pattern, and it is searched for stream names that match. The return value is a map from requested stream name to the matched stream config. By default any settings in StreamConfig::INTERNAL_SETTINGS are removed from the returned stream configs; as they are often not useful for client side configuration. The $includeAllSettings parameter disables this behavior.

Example:

$streamConfigs = MediaWikiServices::getInstance()->getService('EventStreamConfig.StreamConfigs');
$streamConfigs->get( ['test.event', 'mediawiki.edit.cohort1'] );

returns

[
   'test.event' => [
       'sample_rate' => 0.15,
   ],
   'mediawiki.edit.cohort1' => [
       'sample_rate' => 0.8,
   ]
]

streamconfigs MW API endpoint[edit]

curl http://wiki.domain.org/w/api.php?action=streamconfigs&format=json&streams=test.event|mediawiki.edit.cohort1
# returns
{
    "test.event" => {
        "sample_rate" => 0.15
    },
    "mediawiki.edit.cohort1": {
        "sample_rate" => 0.8
    }
}