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The API-Release-Guidelines.md file will be created from the below after the review.
- the definitions of API version, version extension, API version in URL and API name will be copied to the API-Design-Guidelines.md section 5.
- the definition of the API version types
API version types
work-in-progress (wip) API version
The purpose of a work-in-progress API version is to indicate that the API is unstable due to one or more PRs being committed, possibly resulting in temporary inconsistencies.
- A work in progress (wip) API version has wip instead of x.y.z as version number in the API OAS definition file, and vwip in the URL.
- A wip API version may exist in 2 cases
- during the first introduction of a new API upto the creation of the first alpha API version
- during the time that one or more Pull Requests (PRs) are committed after a given release of an API.
- Between different PR commits, the API version remains "wip".
- After or with the last PR commit, the next API version pre-release is prepared.
- The maintainers of the API decide on the release (or not) of the resulting next API version, implying that its corresponding release assets will be created.
alpha (alpha) API version
The purpose of an alpha API version is to support rapid development of an API and the creation of test implementations for feedback purposes.
- An alpha API version (x.y.z
- An alpha API version cannot be part of a CAMARA meta-release. It needs to go through the below API pre-release and release steps first.
release-candidate (rc) API version
The purpose of a release-candidate API version is to allow for (only) bug fixing encountered during further API implementation testing.
- A release-candidate API version (x.y.z-rc.n) is a pre-release of an API version which is stabilized and intended to become the next public-release API version.
- It shall be used to create the API test results and other required release assets.
- A release-candidate API version can be proposed for meta-release. In this case, the public-release API version needs to be prepared in a PR
public-release API version
The purpose of a public-release API version is that it can be used by organization outside CAMARA in application development.
- A public-release API version (x.y.z) is a major/minor/patch stable version of an API.
- A public-release API version with x=0 may exist. This API version is considered to be not yet stable, and is referred as an initial API version.
- A public-release API version with x>0 is referred to as a stable API version.
- A public-release API version is published as part of a CAMARA meta-release.
- To be accepted for meta-release, the public-release API version PR needs to go through TSC approval.
initial public-release API version
A public-release API version is called "initial" to indicate that this API version has not yet reached full maturity, but is considered stable enough to have a public-release as part of a meta-release. It is expected that in the next meta-release this API version becomes stable.
- Initial public-release API versions only exist for new APIs. They are API versions with x = 0 (0.y.z without version extension).
- An initial public-release API version, the API version in the URL may also include the y (minor) version number v0.y (with a dot). This is to simplify the testing of different initial public-release API versions.
- In initial public-release API versions, the y number is increased with breaking changes, the z number is increased with non-breaking changes (see also the exception below).
Exception: for initial public-release API versions:
An update due to a breaking change in a public-release API version 0.y.z results in a next API version: 0.y+1.0. Example: 0.9.0 → 0.10.0
- An update due to a non-breaking change results in an API version change from 0.y.z to API version 0.y.z+1. Example: 0.9.0 → 0.9.1
- After this, -alpha.m and -rc.n extensions shall again be applied throughout the development of the API towards the updated public-release API version.
Initial public-release API versions can be proposed for use in commercial applications, but the user shall be informed that subsequent API versions may require code changes to their applications.
stable public-release API version
A public-release API version is considered "stable" once it has been deployed by at least 2 operators.
- Stable public-release API versions are API versions released after the stability of the API version has been demonstrated through
- certification of the API in at least 2 commercial contexts
- availability and use of the API in at least 2 commercial deployments.
- Once a first stable public-release API version x.y.z has been created (x > 0), normally no further initial public-release API versions (x = 0) shall exist.
Stable public-release API versions are the ones recommended for use in commercial applications. The user can expect that subsequent API versions will be backward-compatible with the one they are using, unless explicitly announced otherwise.
API version types in the release process
The following table gives the values of the API version (Info object) and the API version in the URL (servers object) used in the release process of the API.
NOTE: for initial API versions (x=0), the API version in the URL is exceptionally allowed to contain both the MAJOR and the MINOR version numbers (0.y).
...
public-release
...
x.y.z
...
v0.y
...
vx
...
Yes
Precedence examples:
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Definitions
| Term | Definition |
|---|---|
release | The release of an API version consists in the creation of a GitHub release of the API's repository, with a release tag and (optionally for alpha) a release package. A release can be created for any alpha, release-candidate or public-release API version. No releases are created for wip API versions. |
pre-release | The term pre-release is used to refer to the release of any of the alpha or release-candidate API versions. NOTE: all pre-releases are publicly available in the CAMARA GitHub and can be used AT THE USER'S OWN RISK, as changes may happen to such API versions without notice. |
public-release | The term public-release is used to refer to the release of a public-release API version. It can have the status initial or stable. |
meta-release | A meta-release is a set of public-releases of API versions made available at a given point in time (Spring and Fall). All API versions of a given meta-release shall be aligned to the Commonalities and Identity and Consent Management (ICM) public-releases included in that same meta-release. |
release tag | A release tag is a GitHub tag placed on the main or a maintenance branch that identifies a release of the API version's repository. |
| release package | A release package is a zip file of the repository created using the GitHub release mechanism together with the release tag. It contains a snapshot of the full API Sub Project repository with the content indicated by the release tag. |
API releases
In preparation of a public-release API version, an API Sub Project can create many wip, alpha and release-candidate API versions during the API development. The API versioning is done as described in the API versioning guidelines here: API versioning.
The API Sub Project creates a release for an API version as follows:
- a pre-release may be created for any alpha API version.
- a pre-release must be created for release-candidate API versions.
- a pubic release must be created for public-release API versions
public-releases can have an initial or stable status:
- an initial public-release indicates that the public-release API version is the result of rapid development and is still unstable, e.g. API versions with a v0.x.y version number.
- a stable public-release indicates that the public-release API version is stable and will be maintained.
When planning to deliver a public-release API version into a meta-release, the API Sub Project needs to participate in the meta-release cycle, and provide expected releases according to the meta-release process described here: Meta-release Process. To be part of a meta-release, minimally an initial public-release need to be provided.
Each release must provide the required set of API release assets according to the API readiness checklist described below.
Technically, an API release is created using the GitHub pull request (PR) (with associated GitHub issue) and repository release features, and results in the creation of a GitHub release tag and, if required, a GitHub release package (zip file of the API Sub Project repository).
API releases are numbered (tagged) using the API release numbering guideline (see below).
API release numbering
API release numbers are GitHub tags of the format "rx.y".
IMPORTANT: Release numbers are not related to the API version.
The release numbers shall follow the guidelines described below.
- Release numbers start with x=0 and y=1: r0.1.
- y is incremented by 1 at each subsequent alpha, release-candidate and public-release, and for a maintenance release, e.g. rx.y+1.
- After a meta-release of an API through release rx.y, the next release number for this API is rx+1.0 (y resets to 0).
- In case of maintenance of a release rx.y, the new public-release shall be rx.y+1.
Example of continuous release numbering across the API version.
| API version | release tag | release package | release package tag |
|---|---|---|---|
| work-in-progress | N/A | N/A | N/A |
| alpha | rx.1 ... rx.m | optional | optional [ "pre-release" ] |
| release-candidate | rx.m+1 ... rx.n | mandatory | "pre-release" |
| public-release | rx.n+1 | mandatory | "latest" |
For an API released with rx.y, when preparing the next meta-release, the release numbering starts at rx+1.0.
How to create an API release ?
An API release is created using the GitHub PR and release features and results in:
- a release tag (following the release numbering guidelines below) on the main or on a maintenance release branch, identifying the release of the API version.
- a release package containing the API's repository with the corresponding API release assets for the released API version (zip file). This is optional for intermediate alpha releases.
API releases are numbered (tagged) following the API release numbering guideline (see above).
Releasing an API step by step
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