m273d15 / tfbreak

Tool to identify breaking changes in Terraform modules

TFBreak

This tool helps you to detect breaking changes in Terraform modules and keep track of deprecated variables/outputs.

Breaking Change Detection

You run tfbreak and it tells you if you changed your modules signature. Supported rules so far are:

• Required Terraform version has changed
• Variables
  • A variable was removed
  • A mandatory variable was added
  • A variable type was changed
  • A variable's default value changed (limited since it does not evaluate expression)
• Outputs
  • An output was removed
  • An output type was changed

See pkg/tfbreak/policy/breaking.rego for the implementation details.

Deprecation Warning

You run tfbreak and it warns you about all variables/outputs with a deprecation marker (see the --deprecation-marker option).

Usage

Run for example:

tfbreak \
  -o git::https://github.com/me/my-tf-module?ref=main \
  -n git::https://github.com/me/my-tf-module?ref=my-pr-branch`

to see if your branch introduces new syntactical breaking before merging it.

Help

Usage:
  tfbreak [OPTIONS]

Application Options:
  -o, --old-src=            Old hcl2 code path.
  -n, --new-src=            New hcl2 code path.
      --workdir=            Workdir used to copy the source to (default: '$PWD/.temp_hcl2diff')
      --deprecation-marker= Text in a variable/output description that highlights a deprecation. (default: [Deprecated])

Help Options:
  -h, --help                Show this help message