zuul/README.rst
Joshua Hesketh 3f7def3424 Merge branch 'master' into workingv3
This includes forward-porting changes to launcher/server.py with the
exception of the pre/post playbooks changes which will be done in a
follow up commit as they have deviated.

Change-Id: I13aa229c1460b748745babe178c0a745e52f841c
2016-11-22 11:15:24 +11:00

6.1 KiB

Zuul

Zuul is a project gating system developed for the OpenStack Project.

We are currently engaged in a significant development effort in preparation for the third major version of Zuul. We call this effort Zuul v3 and it is described in more detail below.

Contributing

We are currently engaged in a significant development effort in preparation for the third major version of Zuul. We call this effort Zuul v3 and it is described in this file in the feature/zuulv3 branch of this repo.

To browse the latest code, see: https://git.openstack.org/cgit/openstack-infra/zuul/tree/ To clone the latest code, use git clone git://git.openstack.org/openstack-infra/zuul

Bugs are handled at: https://storyboard.openstack.org/#!/project/679

Code reviews are, as you might expect, handled by gerrit at https://review.openstack.org

Use git review to submit patches (after creating a Gerrit account that links to your launchpad account). Example:

# Do your commits
$ git review
# Enter your username if prompted

Zuul v3

The Zuul v3 effort involves significant changes to Zuul, and its companion program, Nodepool. The intent is for Zuul to become more generally useful outside of the OpenStack community. This is the best way to get started with this effort:

  1. Read the Zuul v3 spec: http://specs.openstack.org/openstack-infra/infra-specs/specs/zuulv3.html

    We use specification documents like this to describe large efforts where we want to make sure that all the participants are in agreement about what will happen and generally how before starting development. These specs should contain enough information for people to evaluate the proposal generally, and sometimes include specific details that need to be agreed upon in advance. They are living documents which can change as work gets underway. However, every change or detail does not need to be reflected in the spec --most work is simply done with patches (and revised if necessary in code review).

  2. Read the Nodepool build-workers spec: http://specs.openstack.org/openstack-infra/infra-specs/specs/nodepool-zookeeper-workers.html

  3. Review any proposed updates to these specs: https://review.openstack.org/#/q/status:open+project:openstack-infra/infra-specs+topic:zuulv3

    Some of the information in the specs may be effectively superceded by changes here, which are still undergoing review.

  4. Read documentation on the internal data model and testing: http://docs.openstack.org/infra/zuul/feature/zuulv3/internals.html

    The general philosophy for Zuul tests is to perform functional testing of either the individual component or the entire end-to-end system with external systems (such as Gerrit) replaced with fakes. Before adding additional unit tests with a narrower focus, consider whether they add value to this system or are merely duplicative of functional tests.

  5. Review open changes: https://review.openstack.org/#/q/status:open+branch:feature/zuulv3

    We find that the most valuable code reviews are ones that spot problems with the proposed change, or raise questions about how that might affect other systems or subsequent work. It is also a great way to stay involved as a team in work performed by others (for instance, by observing and asking questions about development while it is in progress). We try not to sweat the small things and don't worry too much about style suggestions or other nitpicky things (unless they are relevant -- for instance, a -1 vote on a change that introduces a yaml change out of character with existing conventions is useful because it makes the system more user-friendly; a -1 vote on a change which uses a sub-optimal line breaking strategy is probably not the best use of anyone's time).

  6. Join #zuul on Freenode. Let others (especially jeblair who is trying to coordinate and prioritize work) know what you would like to work on.

  7. TODOv3(jeblair): Coming soon: check storyboard for status of current work items. We do not have a list of work items yet, but we will soon.

Once you are up to speed on those items, it will be helpful to know the following:

  • Zuul v3 includes some substantial changes to Zuul, and in order to implement them quickly and simultaneously, we temporarily disabled most of the test suite. That test suite still has relevance, but tests are likely to need updating individually, with reasons ranging from something simple such as a test-framework method changing its name, to more substantial issues, such as a feature being removed as part of the v3 work. Each test will need to be evaluated individually. Feel free to, at any time, claim a test name on this etherpad and work on re-enabling it: https://etherpad.openstack.org/p/zuulv3

  • Because of the importance of external systems, as well as the number of internal Zuul components, actually running Zuul in a development mode quickly becomes unweildy (imagine uploading changes to Gerrit repeatedly while altering Zuul source code). Instead, the best way to develop with Zuul is in fact to write a functional test. Construct a test to fully simulate the series of events you want to see, then run it in the foreground. For example:

    .tox/py27/bin/python -m testtools.run tests.test_scheduler.TestScheduler.test_jobs_launched

    See TESTING.rst for more information.

  • There are many occasions, when working on sweeping changes to Zuul v3, we left notes for future work items in the code marked with "TODOv3". These represent potentially serious missing functionality or other issues which must be resolved before an initial v3 release (unlike a more conventional TODO note, these really can not be left indefinitely). These present an opportunity to identify work items not otherwise tracked. The names associated with TODO or TODOv3 items do not mean that only that person can address them -- they simply reflect who to ask to explain the item in more detail if it is too cryptic. In your own work, feel free to leave TODOv3 notes if a change would otherwise become too large or unweildy.