=======================
 Zuul Interoperability
=======================

What's Zuul?
------------

- Project gating CI system
- Focus on Git and code review workflows
- Cross-project, multi-tenant, multi-source
- Open source/design/development/community
- Host it yourself or use a hosted service
- Represented by the OSF

A Brief History
---------------

- 2012: Speculative scheduler for Jenkins (1.0)
- 2013: Mult-master Jenkins scale out (2.0)
- 2016: Experimental Ansible launcher (2.5)
- 2018: Interoperable rearchitecture (3.0)

https://opensource.com/article/20/2/zuul

Interoperability
----------------

- Ansible as a job description language
- Shares job definitions between repos
- Central "standard library" of building blocks
- Supports multiple source connections
- Runs jobs on many environments and multi-node
- Cross-repo/cross-source dependencies


Ansible Executor
----------------

- Shouldn't invent a domain-specific language
- Avoid "not implemented here" temptation
- Something people were already using
- Made for orchestrating across multiple hosts
- Extensible with Python modules
- Can still easily run arbitrary shell scripts

Job Sharing
-----------

- Workflow/triggers not tied to individual jobs
- Reference jobs and roles from any project
- Vary jobs or inherit from them
- Designed for secure reuse between separate
  * Branches
  * Projects
  * Tenants
  * Connections

Standard Library
----------------

- Reusable building blocks (playbooks, roles)
- Generic jobs for a variety of languages
- Thoroughly documented and self-testing
- Can consume directly through Git connection
- Can consume from a locally-hosted fork
- Advisory testing performed by other sites

https://opendev.org/zuul/zuul-jobs

Multi-Connection
----------------

- Connect to many code review systems at once
- Bridges different review and hosting software
  * Gerrit
  * GitHub
  * Pagure
  * Git (static hosting)
  * GitLab (experimental)
  * BitBucket (in progress)

Job Environments
----------------

- OpenStack (VMs, containers, bare metal)
- Amazon (EC2, EKS)
- Azure (in progress)
- Google Cloud (GCE, GKE)
- Kubernetes pods
- OpenShift
- Static servers and appliances
- Multi-node (homogeneous or heterogeneous)

Dependencies
------------

- Implicit in dependent pipeline manager order
- Explicit in commit message footer
- Works between projects (repositories)
- Works across separate source connections
- Enforces merge sequencing
- Provides prepared Git repositories

Thanks and Links
----------------

Visit https://zuul-ci.org/ for more information

http://fungi.yuggoth.org/presentations/2020-cdf

Copyright 2020 Jeremy Stanley <fungi@yuggoth.org>

This work is licensed under a Creative Commons
Attribution 3.0 Unported License.
http://creativecommons.org/licenses/by/3.0/legalcode