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Extensions are post-fixed to the API version numbers and separated from it by a hyphen "-". m and n are numbers.
All extensions must have a a number (so just "-rc" is not allowed and should be "-rc.1")
Precedence example: 1.0.0 < 1.1.0-alpha.1 < 1.1.0-alpha.2 < 1.1.0-rc.1 < 1.1.0-rc.2 < 1.1.0 (public-release)
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Example: in the URL of an alpha API version 2.y.z-alpha.1, the version in the URL is v2alpha1.
Exception: For initial API versions 0.y.z, the second version number may be include in the URL, e.g. v0.y, to simplify testing of API implementations during API development. In this exception case the "." is kept for readability reasons.
initial API version
- Initial API versions only exist for new APIs. They are They are API versions with x = 0 (API versions 0.y.z-extension. (without extensionn).
- An initial API version may exist for several minor version numbers without extensions, but should at some point become a first an initial alpha API version 0.y.z-alpha.1
- The API version in the URL for initial API versions includes the first 2 may include the major and minor version numbers: v0.y to enable testing during rapid development. No further Applies to initial API versions may be created once the first alpha API version 0.y.z-alpha.1 has been created for the API.ONLY
- Once a first public-release API version has been created (x > 0), no further initial API versions (x = 0) are allowed.
Exception: an initial alpha or release-candidate API version 0.y.z-extension.n may evolve to an initial API version 0.y+1.0 in case of a breaking change or to an initial API version. 0.y.z+1 in case of non-breaking changes. Example: 0.9.0-rc.3 → 0.9.1 (non-breaking change) or 0.10.0 (breaking change).After this -alpha.m and -rc.n extensions can again be applied.
alpha (alpha) API version
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