This is a little awkward since we need to instantiate the providers much
earlier than before. To avoid a lot of reshuffling here we just spin each
one up and then immediately shut it down again, letting our existing init
functionality during the graph walk still do the main initialization.
Due to how deeply the configuration types go into Terraform Core, there
isn't a great way to switch out to HCL2 gradually. As a consequence, this
huge commit gets us from the old state to a _compilable_ new state, but
does not yet attempt to fix any tests and has a number of known missing
parts and bugs. We will continue to iterate on this in forthcoming
commits, heading back towards passing tests and making Terraform
fully-functional again.
The three main goals here are:
- Use the configuration models from the "configs" package instead of the
older models in the "config" package, which is now deprecated and
preserved only to help us write our migration tool.
- Do expression inspection and evaluation using the functionality of the
new "lang" package, instead of the Interpolator type and related
functionality in the main "terraform" package.
- Represent addresses of various objects using types in the addrs package,
rather than hand-constructed strings. This is not critical to support
the above, but was a big help during the implementation of these other
points since it made it much more explicit what kind of address is
expected in each context.
Since our new packages are built to accommodate some future planned
features that are not yet implemented (e.g. the "for_each" argument on
resources, "count"/"for_each" on modules), and since there's still a fair
amount of functionality still using old-style APIs, there is a moderate
amount of shimming here to connect new assumptions with old, hopefully in
a way that makes it easier to find and eliminate these shims later.
I apologize in advance to the person who inevitably just found this huge
commit while spelunking through the commit history.
Implement the adding of provider through the module/providers map in the
configuration.
The way this works is that we start walking the module tree from the
top, and for any instance of a provider that can accept a configuration
through the parent's module/provider map, we add a proxy node that
provides the real name and a pointer to the actual parent provider node.
Multiple proxies can be chained back to the original provider. When
connecting resources to providers, if that provider is a proxy, we can
then connect the resource directly to the proxied node. The proxies are
later removed by the DisabledProviderTransformer.
This should re-instate the 0.11 beta inheritance behavior, but will
allow us to later store the actual concrete provider used by a resource,
so that it can be re-connected if it's orphaned by removing its module
configuration.
Found via a shadow graph failure:
Provider aliases weren't being configured by the new apply graph.
This was caused by the transform that attaches configs to provider nodes
not being able to handle aliases and therefore not attaching a config.
Added a test to this and fixed it.
