Fix Kustomize deprecations

[benwh]

Here's a couple of fixes that we've got in our fork. Details in commit messages.

[0x0013]

Hi @benwh, thanks for this PR.

It seems though that integration test fails after this change. From what I can see, since we are no longer defining the environment variable THEATRE_IMAGE, but rather replace it directly, the vault manager overlay used for acceptance test, which still overlays the command args with the env variable, now results in an invalid read-a-secret-* container, as the image: value no longer corresponds to an existing environment variable.

We still need to define the --theatre-image= in the overlay, otherwise it will inherit the (production) value from the base, so it can't just be removed from the overlay.

I don't think reading the THEATRE_IMAGE value is the purpose of the tests, so it should be fine to directly replace it in the acceptance overlay with the test image used:

# ...
          args:
            - --theatre-image=theatre:latest
            - --metrics-address=0.0.0.0
# ...

I see the tests are failing in your fork as well, though the logs have timed out, I assume the reason is the same.

[0x0013]

@benwh also note that we've merged #338 to update Go version, and with it, we've pinned envtest to 0.19, thus 5975be9 would be unneeded as it pins to an earlier version.

[benwh]

@0x0013 thanks for the pointers!

I've rebased to drop the superseded commit, and updated the acceptance kustomization to fix what I suspect are the issues there (I've been somewhat ignoring the vault-manager stuff, because we don't use that here)

[0x0013]

@benwh Interesting way to solve the acceptance tests issue, by repeating the whole replacement. Though it produces more overlay code, I agree that it's a better approach than just hardcoding the acceptance image in the overlay (- --theatre-image=theatre:latest) as now we use the same replacement pattern in tests as well.

I've left a small suggestion which would hopefully help avoid divergent code in the future.

[0x0013]

with the new approach of repeating this replacement in overlay kustomization, there is a slight risk of someone modifying this replacement code, but forgetting to mirror the modification in overlay, in which case the replacement could be buggy, and the tests would still pass.

I don't think there's an elegant way to solve this, but could you add a code comment that the replacement code needs to be mirrored in config/acceptance/kustomization.yaml?