Reading/Web/EventLogging best practices
This page is currently a draft.
More information and discussion about changes to this draft may be on the discussion page.
- Schemas in MobileFrontend should be prefixed with
- The talk page should be edited with the
SchemaDoctemplate. For example Schema_talk:MobileWebSearch
The Analytics Engineering team offers some thoughts on best privacy practices for when writing schemas.
See the Audiences department's Instrumentation DACI regarding the general process for creating and reviewing schemas.
See Reading/Web/Quantitative_Testing#Sampling_and_bucketing regarding terminology.
Be sure to check events for any newly deployed schema in its Grafana dashboard (linked on the talk page of the schema).
Consideration for experimental features in beta
If wanted you may want to consider a 100% sampling rate in beta. If so, please put this in the acceptance criteria for the task which implements the schema.
Use of tokens
Some events need to be linkable to other events, for example Schema:Popups records several actions occurring within one pageview and within a session. This is usually done via a unique token that is generated once and used until the user closes the browser (session ID, cf. caveats), or moves to a new page (page token). See also phab:T205569. If a schema records both session tokens and page names, one of them should be purged after 90 days.
EventLogging events can be monitored in the browser console (in the Network tab, filter for request URLs containing "event" or "beacon"). But a nicer display of events as MediaWiki notifications can be activated by applying the following code in the console, while being logged in:
mw.loader.using('mediawiki.api.options') .then(() => new mw.Api().saveOption('eventlogging-display-web', '1'));
(See also phab:T188640)
One may need to deactivate Do Not Track and browser extensions that might be blocking EventLogging requests (e.g. Privacy Badger).
It may be necessary to mine a token (session, pageview, or otherwise) in order to test instrumentation consistently, for example during the QA step(s).
If an A/B test is implemented using the
mw.experiments.getBucket function, then the following scripts will mine a token: