releases/doc/source/instructions.rst

Using This Repository

Requesting a Release

The PTL or release liaison for a project may request a release from master by submitting a patch to this repository, adding the necessary release metadata to the file describing the deliverable to be released. The release team will review the request and provide feedback about the version number.

The stable maintenance team, PTL, or release liaison for a project may request a release from a stable branch by submitting a patch to this repository, adding the necessary release metadata to the file describing the deliverable to be released. The release team will review the request and provide feedback about the version number. If the stable release is requested by the stable maintenance team, it should be acknowledged by the PTL or release liaison to ensure that the development team is aware of the coming change.

1. Prepare the release request by submitting a patch to this repository.
   • Set the first line (summary) of the commit message to the package name and version being requested.
   • If you are not the release liaison or PTL, have the PTL of the project acknowledge the request with a +1.
2. Prepare an update to the openstack/requirements repository to change upper-constraints.txt to ensure the new release is tested in the gate. You may also need to update global-requirements.txt in the same patch for a release with new features on which a project depends (bug fix releases do not need the requirements updated). Use a Depends-On tag in the commit message to tie the patch to the original release request so that the requirements and constraints patch will not merge until the release request merges.
3. Leave a comment on the release request linking it to the requirements repository update.

Reviewing a Release Request

Care needs to be taken when reviewing a release request such that the version proposed (1) follows semver rules and (2) will not cause issues between branches, particularly stable branches (at least stable branches that are not yet using upper-constraints checking in CI runs, which is anything before stable/liberty).

General notes when reviewing a release request:

• Make sure you follow semantic versioning rules semver when picking the version number. In particular, if there is a change going into this release which requires a higher minimum version of a dependency, then the minor version should be incremented.

  Note

  The exception to this rule is when the versions of a project are pinned between minor versions in stable branches. In those cases we frequently release global-requirements syncs with a patch version to fix the target branch, e.g. stable/juno, but don't increment the minor version to avoid it being used in a different branch, like stable/kilo. Someone from the stable-maint-core team should +1 a change like this before it's approved.

• Make sure there is a requirements update patch to enable use of the new release. With the constraints system in place, releasing a library is no longer sufficient to cause it to be used in the CI systems. We must explicitly update the constraints file for integration tests, and we want to ensure that the lower bounds accurately reflect the versions needed to provide features for the consuming applications. This latter step is difficult to do accurately via a script, so we need it to be done by the person releasing the library.

• Make sure the summary of the patch includes the deliverable name and version number.

The following rules apply mostly to stable branches and therefore a member of the stable-maint-core team should +1 the following types of changes before they are approved.

• For libraries, check global-requirements.txt (g-r) in the openstack/requirements repo to make sure the version you are about to release does not cause a conflict and wedge the gate. Typically this is only a concern on stable branches with (un)capped dependencies.

  Typical examples of this kind of break (before upper-constraints are used):

  1. A stable branch, for example stable/juno, has uncapped dependencies on a library and a version is released on a newer branch, e.g. stable/kilo, and that version has updated requirements from global-requirements in stable/kilo which conflict with the versions of libraries allowed in stable/juno. This then leads to ContextualVersionConflict failures when installing packages on stable/juno.
  2. Similar to the point above, but if there are overlapping version ranges between two branches, like stable/juno and stable/kilo, you can have the same kinds of issues where a release from one branch which has g-r syncs specific to that branch gets used in the other branch and things break. We saw this happen with oslo.utils 1.4.1 which was intended for stable/juno consumption but because stable/kilo g-r allowed that version, we broke stable/kilo CI jobs since 1.4.1 had juno-level dependencies.

• The rule of thumb is that branches should not overlap versions at the minor version range. For example, stable/juno can require foo>=1.1,<1.2 and stable/kilo can require foo>=1.2,<1.3. In this way only patch-level versions are released for foo on stable/juno and stable/kilo. The pin at the minor version range prevents those patch-level versions from breaking each other's branch.

Release Approval

Releases will only be denied during periods where there are known gate issues, or when releasing will introduce unwanted instability. Releases made late in a week may be delayed until early in the next week unless there is a pressing need such as a gate failure or security issue.

Who is Responsible for the Release?

The release team is responsible for helping to clearly signal the nature of the changes in the release through good version number selection.

The project team is responsible for understanding the implications for consuming projects when a new release is made, and ensuring that releases do not break other projects. When breaks occur, the project team is responsible for taking the necessary corrective action.

Deliverable Files

For deliverable set of projects, we use one YAML file per release series to hold all of the metadata for all releases of that deliverable. For each release, we need to track:

• the launchpad project name (such as oslo.config)
• the series (Kilo, Liberty, etc.)
• for each repository
  • the name (such as openstack/oslo.config)
  • the hash of the commit to be tagged
• the version number to use
• highlights for the release notes email (optional)

We track this metadata for the history of all releases of the deliverable, so we can render a set of release history documentation.

The file should be named based on the deliverable to be tagged, so releases for liberty from the openstack/oslo.config repository will have a file in openstack/releases called deliverables/liberty/oslo.config.yaml. Releases of the same deliverable from the stable/kilo branch will be described by deliverables/kilo/oslo.config.yaml.

Deliverables File Schema

The top level of a deliverable file is a mapping with keys:

launchpad

The slug name of the launchpad project, suitable for use in URLs.

releases

A list of the releases for the deliverable.

Each release entry is a mapping with keys:

version

The version tag for that release, to be applied to all of the member projects.

projects

A list of all of the projects making up the deliverable for that release.

highlights

An optional message to be included in the release note email announcing the release. (Use | to indicate a multi-line, pre-formatted message.)

Each project entry is a mapping with keys:

repo

The name of the repository on git.openstack.org.

hash

The SHA1 hash for the commit to receive the version tag.

Examples

For example, one version of deliverables/liberty/oslo.config.yaml might contain:

---
launchpad: oslo.config
releases:
  - version: 1.12.0
    projects:
      - repo: openstack/oslo.config
        hash: 02a86d2eefeda5144ea8c39657aed24b8b0c9a39

and then for the subsequent release it would be updated to contain:

---
launchpad: oslo.config
releases:
  - version: 1.12.0
    projects:
      - repo: openstack/oslo.config
        hash: 02a86d2eefeda5144ea8c39657aed24b8b0c9a39
  - version: 1.12.1
    projects:
      - repo: openstack/oslo.config
        hash: 0c9113f68285f7b55ca01f0bbb5ce6cddada5023
    highlights: |
       This release includes the change to stop importing
       from the 'oslo' namespace package.

For deliverables with multiple repositories, the list of projects would contain all of them. For example, the Neutron deliverable might be described by deliverables/liberty/neutron.yaml containing:

---
launchpad: neutron
releases:
  - version: 7.0.0
    projects:
      - repo: openstack/neutron
        hash: somethingunique
      - repo: openstack/neutron-fwaas
        hash: somethingunique
      - repo: openstack/neutron-lbaas
        hash: somethingunique
      - repo: openstack/neutron-vpnaas
        hash: somethingunique