Support for version service

[alisonelizabeth]

Kibana has several places where the code diverges between master and 7.x. A good example of this is Upgrade Assistant, although there are other plugins such as Snapshot & Restore and Index Management (others?) where this applies as well.

We propose the core team creates a “version” service that can be used to address this problem. We can use the version number specified in the package.json as the source of truth.

Example usage:

if (version.before(Version.V_8_0_0)) {
  // allow deprecated functionality to proceed
} else {
   throw new Error('this is not unsupported');
}

For more background, see: #78923.

[elasticmachine]

Pinging @elastic/kibana-core (Team:Core)

[pgayvallet]

The version is currently available via PluginInitializerContext.env.packageInfo.version

Comparing can easily be achieved using the semver package

import Semver from 'semver';
Semver.lt(ctx.env.packageInfo.version, '8.0.0')

I agree that such service would add some sugar around that, but the value gain seems small. Or do you foresee see any other API addition later on this version service?

[alisonelizabeth]

Thanks for pointing this out @pgayvallet! I was not aware of this. I think this will serve our needs for now.