Support terraform plan's -target option

[suzuki-shunsuke]

Feature Overview

Allow you to change only given resources using terraform plan's -target option.

Why is the feature needed?

Sometimes you would want to change only specific resources while ignoring changes of other resources.
Especially this is useful when a Terraform Root Module manages a lot of resources and they are managed by multiple people.

Example Code

Introduce a new configuration files: .tfaction/pr/<pr number>.yaml

targets:
  - <resource address>
  - ...

Note

You should use -target option carefully.

https://developer.hashicorp.com/terraform/cli/commands/plan#target-address

Note: Use -target=ADDRESS in exceptional circumstances only, such as recovering from mistakes or working around Terraform limitations.
Refer to Resource Targeting for more details.