system-config/doc/source/zuul.rst

title

Zuul

Zuul

Zuul is a pipeline-oriented project gating system. It facilitates running tests and automated tasks in response to Gerrit events.

At a Glance

Hosts

• http://status.openstack.org/zuul
• http://zuul.openstack.org
• http://zuul-dev.openstack.org

Puppet

• https://git.openstack.org/cgit/openstack-infra/puppet-zuul/tree/
• modules/openstack_project/manifests/zuul_prod.pp
• modules/openstack_project/manifests/zuul_dev.pp

Configuration

• zuul/layout.yaml

Projects

• https://git.openstack.org/cgit/openstack-infra/zuul

Bugs

• https://storyboard.openstack.org/#!/project/679

Resources

• Zuul Reference Manual

Overview

The OpenStack project uses a number of pipelines in Zuul:

check

Newly uploaded patchsets enter this pipeline to receive an initial +/-1 Verified vote from Jenkins.

gate

Changes that have been approved by core developers are enqueued in order in this pipeline, and if they pass tests in Jenkins, will be merged.

post

This pipeline runs jobs that operate after each change is merged.

pre-release

This pipeline runs jobs on projects in response to pre-release tags.

release

When a commit is tagged as a release, this pipeline runs jobs that publish archives and documentation.

silent

This pipeline is used for silently testing new jobs.

experimental

This pipeline is used for on-demand testing of new jobs.

periodic

This pipeline has jobs triggered on a timer for e.g. testing for environmental changes daily.

Zuul watches events in Gerrit (using the Gerrit "stream-events" command) and matches those events to the pipelines above. If a match is found, it adds the change to the pipeline and starts running related jobs.

The gate pipeline uses speculative execution to improve throughput. Changes are tested in parallel under the assumption that changes ahead in the queue will merge. If they do not, Zuul will abort and restart tests without the affected changes. This means that many changes may be tested in parallel while continuing to assure that each commit is correctly tested.

Zuul's current status may be viewed at http://status.openstack.org/zuul/.

Zuul's configuration is stored in zuul/layout.yaml. Anyone may propose a change to the configuration by editing that file and submitting the change to Gerrit for review.

For the full syntax of Zuul's configuration file format, see the Zuul reference manual.

Sysadmin

Zuul and gear are lightweight - it should be possible to run both on a 1G instance for small deployments. OpenStack's deployment requires at least a 2G instance at the time of writing.

Zuul is stateless, so the server does not need backing up. However zuul talks through git and ssh so you will need to manually check ssh host keys as the zuul user. e.g.:

sudo su - zuul
ssh -p 29418 review.openstack.org