* Introduce "Local" terminology for non-absolute provider config addresses
In a future change AbsProviderConfig and LocalProviderConfig are going to
become two entirely distinct types, rather than Abs embedding Local as
written here. This naming change is in preparation for that subsequent
work, which will also include introducing a new "ProviderConfig" type
that is an interface that AbsProviderConfig and LocalProviderConfig both
implement.
This is intended to be largely just a naming change to get started, so
we can deal with all of the messy renaming. However, this did also require
a slight change in modeling where the Resource.DefaultProviderConfig
method has become Resource.DefaultProvider returning a Provider address
directly, because this method doesn't have enough information to construct
a true and accurate LocalProviderConfig -- it would need to refer to the
configuration to know what this module is calling the provider it has
selected.
In order to leave a trail to follow for subsequent work, all of the
changes here are intended to ensure that remaining work will become
obvious via compile-time errors when all of the following changes happen:
- The concept of "legacy" provider addresses is removed from the addrs
package, including removing addrs.NewLegacyProvider and
addrs.Provider.LegacyString.
- addrs.AbsProviderConfig stops having addrs.LocalProviderConfig embedded
in it and has an addrs.Provider and a string alias directly instead.
- The provider-schema-handling parts of Terraform core are updated to
work with addrs.Provider to identify providers, rather than legacy
strings.
In particular, there are still several codepaths here making legacy
provider address assumptions (in order to limit the scope of this change)
but I've made sure each one is doing something that relies on at least
one of the above changes not having been made yet.
* addrs: ProviderConfig interface
In a (very) few special situations in the main "terraform" package we need
to make runtime decisions about whether a provider config is absolute
or local.
We currently do that by exploiting the fact that AbsProviderConfig has
LocalProviderConfig nested inside of it and so in the local case we can
just ignore the wrapping AbsProviderConfig and use the embedded value.
In a future change we'll be moving away from that embedding and making
these two types distinct in order to represent that mapping between them
requires consulting a lookup table in the configuration, and so here we
introduce a new interface type ProviderConfig that can represent either
AbsProviderConfig or LocalProviderConfig decided dynamically at runtime.
This also includes the Config.ResolveAbsProviderAddr method that will
eventually be responsible for that local-to-absolute translation, so
that callers with access to the configuration can normalize to an
addrs.AbsProviderConfig given a non-nil addrs.ProviderConfig. That's
currently unused because existing callers are still relying on the
simplistic structural transform, but we'll switch them over in a later
commit.
* rename LocalType to LocalName
Co-authored-by: Kristin Laemmert <mildwonkey@users.noreply.github.com>
Since schemas are required to interpret provider, resource, and
provisioner attributes in configs, states, and plans, these helpers intend
to make it easier to gather up the the necessary provider types in order
to preload all of the needed schemas before beginning further processing.
Config.ProviderTypes returns directly the list of provider types, since
at this level further detail is not useful: we've not yet run the
provider allocation algorithm, and so the only thing we can reliably
extract here is provider types themselves.
State.ProviderAddrs and Plan.ProviderAddrs each return a list of
absolute provider addresses, which can then be turned into a list of
provider types using the new helper providers.AddressedTypesAbs.
Since we're already using configs.Config throughout core, this also
updates the terraform.LoadSchemas helper to use Config.ProviderTypes
to find the necessary providers, rather than implementing its own
discovery logic. states.State is not yet plumbed in, so we cannot yet
use State.ProviderAddrs to deal with the state but there's a TODO comment
to remind us to update that in a later commit when we swap out
terraform.State for states.State.
A later commit will probably refactor this further so that we can easily
obtain schema for the providers needed to interpret a plan too, but that
is deferred here because further work is required to make core work with
the new plan types first. At that point, terraform.LoadSchemas may become
providers.LoadSchemas with a different interface that just accepts lists
of provider and provisioner names that have been gathered by the caller
using these new helpers.
Martin Atkins