Add Warning for Deprecated Modules in Init

[Maed223]

Jira Ticket

Target Release

1.8.x

Draft CHANGELOG entry

ENHANCEMENTS

• terraform init: Displays a warning when deprecated modules are in use.

Description

All module deprecation info is consolidated into and displayed as a single warning upon running terraform init. This includes both cases of where the module does, or does not, need installation. Furthermore, the warning can be raised for both modules that are directly used in configuration, as well as any external dependencies they depend on.

Screenshot

Note that this screenshot includes both the root module as well as it's external dependencies

[brandonc]

Some early questions that will help me get my bearings on this PR

[brandonc]

Curious: Why couldn't the ModuleInstaller itself build the deprecation warnings and add them to the instDiags that are already returned? It would seem that would simplify the interface greatly.

[brandonc]

My rationale is that they are being appended to diags along with instDiags, without further differentiation

[Maed223]

This comes from the requirement that we consolidate the deprecations into a single warning, as well as having a means of showing the hierarchy in which a deprecated module sits (i.e. the (Root: a -> b -> c) parts of the warning).

[brandonc]

These backend go mod changes look out of place because no other changes are in the package. What's going on with them?

[Maed223]

This is something I'm not 100% sure on, but it seems to me that change was needed since I added the dependency to configs package, which is somehow a dependency of backend package. Without this change I was getting failures in "Code Consistency Checks" test on CI, as well as some failing unit tests due to the missing presence of the dependency. This change and it's related changes are the result of running make syncdeps.

[Maed223]

Took some edits to how the Detail of diagnostics are handled in the format package, but was able to remove the direct colorization in the configs package that subsequently removes the need for these changes.

Included here 7b3e8a1

Otherwise dropped the previous commit that included the go.mod and go.sum changes

[Maed223]

@nfagerlund– just to address some of your points ✍️

TFE Version of this warning

• The json output for init was added by @Uk1288 in this PR, is that what you are referring to with "json log format"? Otherwise we have ongoing work in the agent to bring it all together.

Passing deprecations as a return value separate from configs.Config

• configs.Config seemed to me to represent info that is specifically relevant to configuration (as it pertains to the direct usage of the module) and distinctly separate to something like deprecation metadata just used for a warning. Though I definitely see the argument that utilizing this existing structure is advantageous in retrospect.
• Additionally, it looked to me that for root modules certain bits of needed info wouldn't be present, leading to adding redundant info for all Configs (such as Version not being present for the root, so I'd have to insert the Version through other means for all modules in the Config tree). This in combination with my thought above led me to keep them separate. Though in total, If you feel strongly about this I'll defer to your wisdom and make the change 😁

Changes in go-slug/sourcebundle

• We have work planned to do just that 😁