Page MenuHomePhabricator

Replace EventLogging with Confluent Platform
Closed, DeclinedPublic



  • Reduce the surface of Wikimedia-specific code we need to maintain.
  • Horizontal scalability.
  • Excellent integration with Kafka, which we are already committed to.
  • Schema evolution capabilities; backward/forward compatibility.
  • Tight integration with Hadoop ecosystem.
  • Efficient binary serialization.


  • Articulate the value of this migration and get buy-in from stakeholders. (See 'Why', above.)
  • Package and Puppetize the Confluent schema registry.
  • Package and Puppetize Kafka REST Proxy.
  • Upgrade Kafka to a version compatible with Confluent Platform.
  • Write a MediaWiki extension that provides an interface for creating, editing, and browsing schema, and which uses the schema registry as a storage backend.
  • Set all of the above up in labs.
    • Fully implement a particular proof-of-concept, so that people can actually see how this works.
  • Design a public event-logging endpoint and solicit a security review.
  • Migrate existing schema to Avro? (Maybe not.)

Event Timeline

ori created this task.Jun 10 2015, 11:19 PM
ori assigned this task to Ottomata.
ori raised the priority of this task from to Medium.
ori updated the task description. (Show Details)
ori added a project: Analytics-EventLogging.
ori added subscribers: ori, Ottomata.
Restricted Application added a subscriber: Aklapper. · View Herald TranscriptJun 10 2015, 11:19 PM

Confluent experiments:

See also labs host

ori added a comment.Jun 11 2015, 4:08 AM


While I like the idea, I think the overhead of moving from json to Avro is really not to be neglected.

If this works as it should, users will be able to produce their data in JSON format.

Design a public event-logging endpoint and solicit a security review.

This part will be interesting. I think production of messages can be limited to the same annoyances as eventlogging pretty easily, but simply forcing clients to submit valid schemas. That is slightly better than eventlogging is now, as currently anyone can submit anything into the raw client side 0mq stream.

However, the Kafka REST Proxy does have a consumer interface, and we certainly want to restrict that to internal use only. I suppose we can do this with HTTP URI level restrictions (in varnish, nginx, apache, loadbalancer, whatever), but I'm not sure if that is the best way to do this. Its also all open source, so we could patch or fork however we like:

Ottomata closed this task as Declined.Jan 18 2016, 7:29 PM

EventBus was done instead.