I have configured a fleet.yaml file to reference a helm chart using the helm.chart field. I have had more or less success with this approach, depending on where I locate the fleet.yaml and modifying the chart path accordingly.
In particular, it seems that a relative chart path that includes ../ will not work. E.g. the following does not work…
Relative paths within the repo should work, so if this file is at least 3 dirs deep and referring to a kubernetes folder elsewhere in this repo that should work. If it doesn’t please put in an issue in rancher/fleet (ideally with an example repo that reproduces it).
Going outside of the root of the repo to random parent directories is intentionally supposed to not work (../../../../../../../etc/passwd).