Background

Per @jwang's data QA for T353029: QA desktopwebuiactionstracking schema port to the new metrics platform in https://phabricator.wikimedia.org/T353029#9622128:

pageNamespace	❌	page.namespace_id is NULL in new schema

AC

• When correctly configured, the JS client library captures page.namespace_id

Notes

1. This is happening because the integration in EventLogging is returning the namespace ID as the page.namespace property: https://github.com/wikimedia/mediawiki-extensions-EventLogging/blob/b03e1685586074514fd1e3a1b3f8d408414cc8e4/modules/ext.eventLogging/MediaWikiMetricsClientIntegration.js#L127