This fixes the run package's leaky abstraction; other packages no longer
need to know or care that run.Config even exists.
Note that since the various Steps now depend on having a non-nil pointer
to a run.Config, it's unsafe (or at least risky) to initialize them
directly. They should be created with their NewSTEPNAME functions. All
their fields are now private, to reflect this.
This is the first step toward removing run.Config entirely. InitKube was
the only Step that even used cfg in its Execute function; the rest just
discarded it.
Now that InitKube, AddRepo, and UpdateDependencies are initialized with
NewSTEPNAME functions, the helper functions in plan.go are
unnecessary--they do too little to be a useful abstraction, and they
aren't complex or frequently-used enough to be worth extracting.
This seems to be be a more natural separation of concerns--the knowledge
of which config fields map to which parts of a Step belong to the Step,
not to the Plan.
I'd like to be able to make calls like NewUpgrade(cfg) rather than
Upgrade{...}.Prepare, but I wouldn't be able to define a NewUpgrade
function while Config is in the helm package; there would be a circular
import when Plan tried to import run.
While writing docs in the previous commit, I noticed that we'd been
inconsistent in the naming scheme. Wikipedia's back-compat article
redirects from "backwards" to "backward", so I figure that's a
reasonable source of authority for which form to use.
I don't love the mismatch between the helm.Config field (CleanupOnFail)
and the setting name (cleanup_failed_upgrade). I do think the setting
name should contain "upgrade" since it's specific to the upgrade command,
but if I make the config field CleanupFailedUpgrade, it becomes the new
longest field name, and gofmt creates a bunch of churn. Is that a good
enough reason...?
Redacting KubeToken may not be sufficient, since it's possible that
someone would put secrets in Values or StringValues. Unilaterally
redacting those seems unhelpful, though, since they may be the very
thing the user is trying to debug. I've settled on redacting the obvious
field without trying to promise that all sensitive data will be hidden.
Helm3 renamed its delete command to uninstall. We should still accept
helm_command=delete for drone-helm compatibility, but the internals
should use Helm's preferred name.
This change revealed more about how the system needs to work, so there
are some supporting changes:
* helm.upgrade and helm.help are now vars rather than raw functions.
This allows unit tests to target the "which step should we run"
logic directly by comparing function pointers, rather than having to
configure/prepare a fully-valid Plan and then infer the logic’s
correctness based on the Plan’s state.
* configuration that's specific to kubeconfig initialization is now part
of the InitKube struct rather than run.Config, since other steps
shouldn’t need access to those settings (particularly the secrets).
* Step.Execute now receives a run.Config so it can log debug output.
I'm vacillating about the choice to have separate Config structs in the
`helm` and `run` packages. I can't tell whether it's "good separation of
concerns" or "cumbersome and over-engineered." It seems appropriate at
the moment, though.
