Project Testing Interface

OpenStack has a lot of projects. For each project, the OpenStack CI system needs to be able to perform a lot of tasks. If each project has a slightly different way to accomplish those tasks, it makes the management of a consistent testing infrastructure very difficult to deal with. Additionally, because of the high volume of development changes and testing, the testing infrastructure has to be able to pre-cache artifacts that are normally fetched over the internet. To that end, each project should support a consistent interface for driving tests and other necessary tasks.

The following tasks are required for every project. Every project must:

  • Execute tests

  • Enforce code style

  • Generate a code coverage report

  • Generate a source tarball

  • Generate documentation

  • Generate releasenotes

The following are other common tasks, which may not be relevant for every project:

  • Enforce code coverage

  • Generate a release artifact

  • Publish a release artifact

  • Import translation strings

  • Export translation strings

Tools and approaches vary by language, please choose which language is relevant to you.


Project Testing Interface defines a minimal list of platforms that projects should test against. Having a more extensive set of tested platforms (for instance, keeping older platforms that are not yet EOL) is both allowed and encouraged.


OpenStack has decided to standardize on using Sphinx for project documentation, regardless of programming language.


The use of sphinx for documentation is intended for documentation that is not written inside of docstrings or code comments. Languages, such as Go, that natively support a system for documenting the code through code comments, should use those native systems. Sphinx is intended to be used for documentation that is not written inline with the code.

To support documentation generation, projects should:

  • Have sphinx documentation source in doc/source

  • List python dependencies needed for documentation in doc/requirements.txt

  • List distro package pre-reqs for dependencies in bindep.txt using the doc tag.

  • Depend on openstackdocstheme for documentation and configure it to be used in doc/source/

  • Have a docs environment set up in a tox.ini file within the repository.

Assuming non-Python requirements have been properly installed as indicated by bindep.txt, the following command should work with no additional setup and should result in the documentation being emitted into doc/build/html.

tox -e docs


We strongly discourage project teams from adding commands to the docs environment beyond:

sphinx-build -W -b html doc/source doc/build/html

Additional logic needed around Sphinx generation should go into Sphinx plugins.

Language specific instructions supplement these and are in addition to them.

Release Notes

OpenStack uses reno for generating release notes regardless of programming language.

To support releasenotes generation, projects should:

  • Have releasenotes documentation source in releasenotes/

  • Configure openstackdocstheme to be used in releasenotes/source/

  • Optionally list distro package pre-reqs for dependencies in bindep.txt using the releasenotes tag.

Assuming requirements have been properly installed, the following command should work with no additional setup and should result in the releasenotes being emitted into releasenotes/build/html.

sphinx-build -a -E -W -d releasenotes/build/doctrees -b html \
    releasenotes/source releasenotes/build/html

Language specific instructions supplement these and are in addition to them.

Linux Distributions

The following free operating systems are representative of platforms regularly used to deploy OpenStack on:

Below are the two upstream testing required as minimum to consider the above distro for defining the testing runtime:

  • devstack support with distro job as voting

  • One of the deployment projects run OpenStack on distro

Tested Runtimes

In order to focus development efforts and prevent breaking changes midway through a development cycle, the policy for officially tested runtimes is based on the LTS or stable release of the Linux Distributions at the start of the development cycle. Distros are listed in testing runtime based on the required minimum testing as described in Linux Distributions

Upgrade testing

Along with testing the distro versions defined in testing runtime, projects need to take care of the supported upgrade path also. For the supported upgrade path, projects need to make sure that new release code and its supported configuration works on the distros supported by the upgrade-supported previous releases of OpenStack.

With SLURP upgrade support, along with release to release (N-1 -> N) upgrade we need to take care of skip-level upgrade also.

  1. non-SLURP release N (N-1 -> N upgrade)

    Every non-SLURP release need to support N-1 -> N upgrade. In this upgrade path, N (non-SLURP release) code and supported configuration should continue working on distro versions supported and defined by the N-1 release testing runtime.

  2. SLURP release N (N-1 -> N and N-2 -> N upgrade)

    Every SLURP release need to support N-1 -> N as well as the N-2 -> N upgrade. In this upgrade path, N (SLURP release) code and supported configuration should continue working on distro versions supported and defined by the N-1 as well as the N-2 release testing runtime.

For smooth upgrade, try to avoid changes in dependencies which are not present in old release supported distro. In case any project has to do it due to its new features dependencies then communicate it explicitly in upgrade status tool, release notes etc. Also, make it clear if project existing functionality can still work fine on the old distro version but the new features require the new distro version will not be available until the distro version is upgraded.

Extending support and testing for release with the newer disto version

When any release bumps the minimum supported distro platform or python version, the following things need to be addressed:

  1. Support the old distro version also along with the new version. Basically two distro versions will be supported in testing runtime for a release changing the distro version. Explicitly mention about old PTI support in testing runtime.

    • For old distro version testing, we do not need to run all jobs on that version, instead running a single tempest job in project gate on old distro version will be sufficient.

    • Make sure to keep the old distro default python version in testing runtime.

    Example: 2023.1 cycle testing runtime

  2. Do not add the new PTI (distro, python new version) to the non-SLURP testing runtime. We may need to remove the old PTI which was additionally supported for smooth upgrade in previous release. If we have to add the new PTI in the non-SLURP testing runtime then we need to make sure the old distro supported in the immediately previous SLURP release is also tested in the next SLURP release. This will make sure that the old and the new distros are tested between SLURP releases also.

The verification can be done via integrated testing and upgrade testing for example, tempest, grenade or similar upgrade testing jobs running with default and supported configuration.

The officially tested runtimes for each cycle can be found here: