Deprecated marks a specific handler as a deprecated.

GetVersion returns the current request version.

Handler returns a handler which stop the execution when the given "version" does not match with the requested one.

If reports whether the "version" is matching to the "is".

Match acts exactly the same as `If` does but instead it accepts a Context, so it can be called by a handler to determinate the requested version.

NewGroup returns a ptr to Group based on the given "version".

NewMatcher creates a single handler which decides what handler should be executed based on the requested version.

SetVersion force-sets the API Version.

WriteDeprecated writes the deprecated response headers based on the given "options".

AcceptHeaderKey is the header key of "Accept".

AcceptHeaderVersionValue is the Accept's header value search term the requested version.

AcceptVersionHeaderKey is the header key of "Accept-Version".

Key is the context key of the version, can be used to manually modify the "requested" version.

NotFound is the key that can be used inside a `Map` or inside `ctx.SetVersion(versioning.NotFound)` to tell that a version wasn't found, therefore the not found handler should handle the request instead.

DefaultDeprecationOptions are the default deprecation options, it defaults the "X-API-Warn" header to a generic message.

ErrNotFound reports whether a requested version does not match with any of the server's implemented ones.

NotFoundHandler is the default version not found handler that is executed from `NewMatcher` when no version is registered as available to dispatch a resource.

DeprecationOptions describes the deprecation headers key-values.

Group is a group of version-based routes.

Map is a map of versions targets to a handlers, a handler per version or constraint, the key can be something like ">1, <=2" or just "1".