Validate installation of Rancher charts through Fleet

[kkaempf]

Fleet should eventually be able to install charts available on the Rancher Marketplace and the SUSE Application Collection (2 different sources).

An important step to making this possible is ensuring that installing those charts through Fleet is supported.

Steps:

1. Identify the most important charts
2. Test Rancher charts for installability with Fleet #4465
3. Best practices for charts to work nicely with Fleet fleet-product-docs#134
4. Test automation for Rancher charts #4466

Sources for charts:

• Rancher charts
  • Release branches (release-vX.YZ, also dev-vX.YZ?)
• Partner charts
  • Branches main-source or main should both work. main is used by Rancher.
  • Check charts' created (date) and deprecated (boolean, optional, false by default) fields to identify still maintained charts in index.yaml

Warning: some installation failures may be caused by charts not coming with default values: actual values used at install time may come from the Marketplace UI.

Open points

• Each chart is available in multiple version; which versions should be tested? → Decision to make and document

• Similarly, which Fleet releases should be tested for this?

  • Possible answer: whichever Fleet version will be pinned in Rancher once the Marketplace can link to Fleet would be a good pick, e.g. starting with main/currently v0.15 could make sense to begin with.

• When should a test pipeline run?

  • For each new Fleet release (on supported release branches)? → run pipeline against all charts?
  • For each new release of a validated chart → run pipeline for the chart against all supported Fleet releases?