TFLint Ruleset Prettier

A TFLint ruleset that enforces formatting and style conventions for Terraform code.

Requirements

• TFLint v0.46+
• Go v1.26

Installation

You can install the plugin with tflint --init. Declare a config in .tflint.hcl as follows:

plugin "prettier" {
  enabled = true

  version = "0.2.0"
  source  = "github.com/joshuaspence/tflint-ruleset-prettier"
}

Rules

Name	Description	Severity	Enabled By Default	Link
aws_hardcoded_ids	Validates that there are no hardcoded AWS account IDs or AMI IDs	WARNING	✅	docs
aws_iam_policy_hardcoded_partition	Validates that there are no hardcoded AWS partitions in IAM policy documents	WARNING	✅	docs
aws_iam_policy_hardcoded_region	Validates that there are no hardcoded AWS regions in IAM policy documents	WARNING	✅	docs
aws_iam_role_policy_hardcoded_partition	Validates that there are no hardcoded AWS partitions in IAM role policy documents	WARNING	✅	docs
aws_iam_role_policy_hardcoded_region	Validates that there are no hardcoded AWS regions in IAM role policy documents	WARNING	✅	docs
aws_meta_hardcoded	Validates that there are no hardcoded AWS regions or partitions in ARN values across all resource types	WARNING	✅	docs
aws_provider_hardcoded_region	Validates that there are no hardcoded AWS regions in provider configuration	WARNING	✅	docs
aws_service_principal_dns_suffix	Validates that service principals don't use dns_suffix interpolation	WARNING	✅	docs
aws_service_principal_hardcoded	Validates that service principals don't use hardcoded DNS suffixes (e.g., amazonaws.com)	WARNING	✅	docs
aws_policy_no_jsonencode	Flags use of jsonencode() in policy attributes on AWS resources	NOTICE	✅	docs
output_must_be_in_outputs_file	Ensures all output blocks are declared in outputs.tf	NOTICE	✅	docs
typed_variables	Ensures all variables have an explicit type constraint	WARNING	✅	docs
variable_must_be_in_variables_file	Ensures all variable blocks are declared in variables.tf	NOTICE	✅	docs
indented_heredoc	Suggests indented heredoc syntax (<<-) instead of standard heredoc (<<)	NOTICE	✅	docs
list_trailing_comma	Validates that the last item in a multi-line list ends with a trailing comma	NOTICE	✅	docs
map_trailing_comma	Validates that maps have consistent trailing commas	NOTICE	✅	docs
variables_order	Validates that variable blocks are sorted alphabetically	NOTICE	✅	docs

Building the plugin

Clone the repository locally and run the following command:

$ make

You can easily install the built plugin with the following:

$ make install

You can run the built plugin like the following:

$ cat << EOS > .tflint.hcl
plugin "prettier" {
  enabled = true
}
EOS
$ tflint