Cannot run 7.x build candidates with snapshot registry

[axw]

I'd like to test the 7.12 build candidates with Fleet, using the APM package in the snapshot package registry. When running a build candidate of Kibana, it will interact with the production package registry by default. This can be overridden with XPACK_FLEET_REGISTRYURL (xpack.fleet.registryUrl).

When running the managed APM Server service, one can pass the --package-registry-snapshot flag to direct it to use the snapshot registry. However, this only sets XPACK_FLEET_REGISTRYURL for the managed APM Server service. It should also be set for the Kibana process, so Kibana can fetch packages from the appropriate registry.

[kuisathaverat]

I think this setting is not implemented yet, IIRC the registry is forced based on the version you are using see elastic/kibana#90327

[axw]

Yep, I'm in the process of adding a flag to control the registry URL used in Kibana.