Collection of git hooks for Terraform to be used with pre-commit framework

Want to contribute? Check open issues and contributing notes.

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Table of content

• Sponsors
• Table of content
• How to install
  • 1. Install dependencies
  • 2. Install the pre-commit hook globally
  • 3. Add configs and hooks
  • 4. Run
• Available Hooks
• Hooks usage notes and examples
  • All hooks: Usage of environment variables in --args
  • All hooks: Set env vars inside hook at runtime
  • All hooks: Disable color output
  • checkov (deprecated) and terraform_checkov
  • infracost_breakdown
  • terraform_docs
  • terraform_docs_replace (deprecated)
  • terraform_fmt
  • terraform_providers_lock
  • terraform_tflint
  • terraform_tfsec
  • terraform_validate
  • terraform_wrapper_module_for_each
  • terrascan
  • tfupdate
• Docker Usage: File Permissions
• Authors
• License
  • Additional information for users from Russia and Belarus

How to install

1. Install dependencies

• pre-commit
• checkov required for checkov hook.
• terraform-docs required for terraform_docs hook.
• terragrunt required for terragrunt_validate hook.
• terrascan required for terrascan hook.
• TFLint required for terraform_tflint hook.
• TFSec required for terraform_tfsec hook.
• infracost required for infracost_breakdown hook.
• jq required for infracost_breakdown hook.
• tfupdate required for tfupdate hook.
• hcledit required for terraform_wrapper_module_for_each hook.

Docker

Pull docker image with all hooks:

TAG=latest
docker pull ghcr.io/antonbabenko/pre-commit-terraform:$TAG

All available tags here.

Build from scratch:

When --build-arg is not specified, the latest version of pre-commit and terraform will be only installed.

git clone [email protected]:antonbabenko/pre-commit-terraform.git
cd pre-commit-terraform
# Install the latest versions of all the tools
docker build -t pre-commit-terraform --build-arg INSTALL_ALL=true .

To install a specific version of individual tools, define it using --build-arg arguments or set it to latest:

docker build -t pre-commit-terraform \
    --build-arg PRE_COMMIT_VERSION=latest \
    --build-arg TERRAFORM_VERSION=latest \
    --build-arg CHECKOV_VERSION=2.0.405 \
    --build-arg INFRACOST_VERSION=latest \
    --build-arg TERRAFORM_DOCS_VERSION=0.15.0 \
    --build-arg TERRAGRUNT_VERSION=latest \
    --build-arg TERRASCAN_VERSION=1.10.0 \
    --build-arg TFLINT_VERSION=0.31.0 \
    --build-arg TFSEC_VERSION=latest \
    --build-arg TFUPDATE_VERSION=latest \
    --build-arg HCLEDIT_VERSION=latest \
    .

Set -e PRE_COMMIT_COLOR=never to disable the color output in pre-commit.

MacOS

brew install pre-commit terraform-docs tflint tfsec checkov terrascan infracost tfupdate minamijoyo/hcledit/hcledit jq

Ubuntu 18.04

sudo apt update
sudo apt install -y unzip software-properties-common
sudo add-apt-repository ppa:deadsnakes/ppa
sudo apt install -y python3.7 python3-pip
python3 -m pip install --upgrade pip
pip3 install --no-cache-dir pre-commit
python3.7 -m pip install -U checkov
curl -L "$(curl -s https://api.github.com/repos/terraform-docs/terraform-docs/releases/latest | grep -o -E -m 1 "https://.+?-linux-amd64.tar.gz")" > terraform-docs.tgz && tar -xzf terraform-docs.tgz && rm terraform-docs.tgz && chmod +x terraform-docs && sudo mv terraform-docs /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/terraform-linters/tflint/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.zip")" > tflint.zip && unzip tflint.zip && rm tflint.zip && sudo mv tflint /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/aquasecurity/tfsec/releases/latest | grep -o -E -m 1 "https://.+?tfsec-linux-amd64")" > tfsec && chmod +x tfsec && sudo mv tfsec /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/tenable/terrascan/releases/latest | grep -o -E -m 1 "https://.+?_Linux_x86_64.tar.gz")" > terrascan.tar.gz && tar -xzf terrascan.tar.gz terrascan && rm terrascan.tar.gz && sudo mv terrascan /usr/bin/ && terrascan init
sudo apt install -y jq && \
curl -L "$(curl -s https://api.github.com/repos/infracost/infracost/releases/latest | grep -o -E -m 1 "https://.+?-linux-amd64.tar.gz")" > infracost.tgz && tar -xzf infracost.tgz && rm infracost.tgz && sudo mv infracost-linux-amd64 /usr/bin/infracost && infracost register
curl -L "$(curl -s https://api.github.com/repos/minamijoyo/tfupdate/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.tar.gz")" > tfupdate.tar.gz && tar -xzf tfupdate.tar.gz tfupdate && rm tfupdate.tar.gz && sudo mv tfupdate /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/minamijoyo/hcledit/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.tar.gz")" > hcledit.tar.gz && tar -xzf hcledit.tar.gz hcledit && rm hcledit.tar.gz && sudo mv hcledit /usr/bin/

Ubuntu 20.04

sudo apt update
sudo apt install -y unzip software-properties-common python3 python3-pip
python3 -m pip install --upgrade pip
pip3 install --no-cache-dir pre-commit
pip3 install --no-cache-dir checkov
curl -L "$(curl -s https://api.github.com/repos/terraform-docs/terraform-docs/releases/latest | grep -o -E -m 1 "https://.+?-linux-amd64.tar.gz")" > terraform-docs.tgz && tar -xzf terraform-docs.tgz terraform-docs && rm terraform-docs.tgz && chmod +x terraform-docs && sudo mv terraform-docs /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/tenable/terrascan/releases/latest | grep -o -E -m 1 "https://.+?_Linux_x86_64.tar.gz")" > terrascan.tar.gz && tar -xzf terrascan.tar.gz terrascan && rm terrascan.tar.gz && sudo mv terrascan /usr/bin/ && terrascan init
curl -L "$(curl -s https://api.github.com/repos/terraform-linters/tflint/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.zip")" > tflint.zip && unzip tflint.zip && rm tflint.zip && sudo mv tflint /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/aquasecurity/tfsec/releases/latest | grep -o -E -m 1 "https://.+?tfsec-linux-amd64")" > tfsec && chmod +x tfsec && sudo mv tfsec /usr/bin/
sudo apt install -y jq && \
curl -L "$(curl -s https://api.github.com/repos/infracost/infracost/releases/latest | grep -o -E -m 1 "https://.+?-linux-amd64.tar.gz")" > infracost.tgz && tar -xzf infracost.tgz && rm infracost.tgz && sudo mv infracost-linux-amd64 /usr/bin/infracost && infracost register
curl -L "$(curl -s https://api.github.com/repos/minamijoyo/tfupdate/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.tar.gz")" > tfupdate.tar.gz && tar -xzf tfupdate.tar.gz tfupdate && rm tfupdate.tar.gz && sudo mv tfupdate /usr/bin/
curl -L "$(curl -s https://api.github.com/repos/minamijoyo/hcledit/releases/latest | grep -o -E -m 1 "https://.+?_linux_amd64.tar.gz")" > hcledit.tar.gz && tar -xzf hcledit.tar.gz hcledit && rm hcledit.tar.gz && sudo mv hcledit /usr/bin/

Windows 10/11

We highly recommend using WSL/WSL2 with Ubuntu and following the Ubuntu installation guide. Or use Docker.

Note: We won't be able to help with issues that can't be reproduced in Linux/Mac. So, try to find a working solution and send PR before open an issue.

Otherwise, you can follow this gist:

1. Install git and gitbash
2. Install Python 3
3. Install all prerequisites needed (see above)

Ensure your PATH environment variable looks for bash.exe in C:\Program Files\Git\bin (the one present in C:\Windows\System32\bash.exe does not work with pre-commit.exe)

For checkov, you may need to also set your PYTHONPATH environment variable with the path to your Python modules.
E.g. C:\Users\USERNAME\AppData\Local\Programs\Python\Python39\Lib\site-packages

2. Install the pre-commit hook globally

Note: not needed if you use the Docker image

DIR=~/.git-template
git config --global init.templateDir ${DIR}
pre-commit init-templatedir -t pre-commit ${DIR}

3. Add configs and hooks

Step into the repository you want to have the pre-commit hooks installed and run:

git init
cat <<EOF > .pre-commit-config.yaml
repos:
- repo: https://github.com/antonbabenko/pre-commit-terraform
  rev: <VERSION> # Get the latest from: https://github.com/antonbabenko/pre-commit-terraform/releases
  hooks:
    - id: terraform_fmt
    - id: terraform_docs
EOF

4. Run

Execute this command to run pre-commit on all files in the repository (not only changed files):

pre-commit run -a

Or, using Docker (available tags):

NOTE: This command uses your user id and group id for the docker container to use to access the local files. If the files are owned by another user, update the USERID environment variable. See File Permissions section for more information.

TAG=latest
docker run -e "USERID=$(id -u):$(id -g)" -v $(pwd):/lint -w /lint ghcr.io/antonbabenko/pre-commit-terraform:$TAG run -a

Execute this command to list the versions of the tools in Docker:

TAG=latest
docker run --rm --entrypoint cat ghcr.io/antonbabenko/pre-commit-terraform:$TAG /usr/bin/tools_versions_info

Available Hooks

There are several pre-commit hooks to keep Terraform configurations (both *.tf and *.tfvars) and Terragrunt configurations (*.hcl) in a good shape:

Hook name	Description	Dependencies Install instructions here
checkov and terraform_checkov	checkov static analysis of terraform templates to spot potential security issues. Hook notes	checkov Ubuntu deps: python3, python3-pip
infracost_breakdown	Check how much your infra costs with infracost. Hook notes	infracost, jq, Infracost API key
terraform_docs	Inserts input and output documentation into README.md. Recommended. Hook notes	terraform-docs
terraform_docs_replace	Runs terraform-docs and pipes the output directly to README.md. DEPRECATED, see #248. Hook notes	python3, terraform-docs
terraform_docs_without_ aggregate_type_defaults	Inserts input and output documentation into README.md without aggregate type defaults. Hook notes same as for terraform_docs	terraform-docs
terraform_fmt	Reformat all Terraform configuration files to a canonical format. Hook notes	-
terraform_providers_lock	Updates provider signatures in dependency lock files. Hook notes	-
terraform_tflint	Validates all Terraform configuration files with TFLint. Available TFLint rules. Hook notes.	tflint
terraform_tfsec	TFSec static analysis of terraform templates to spot potential security issues. Hook notes	tfsec
terraform_validate	Validates all Terraform configuration files. Hook notes	-
terragrunt_fmt	Reformat all Terragrunt configuration files (*.hcl) to a canonical format.	terragrunt
terragrunt_validate	Validates all Terragrunt configuration files (*.hcl)	terragrunt
terraform_wrapper_module_for_each	Generates Terraform wrappers with for_each in module. Hook notes	hcledit
terrascan	terrascan Detect compliance and security violations. Hook notes	terrascan
tfupdate	tfupdate Update version constraints of Terraform core, providers, and modules. Hook notes	tfupdate

Check the source file to know arguments used for each hook.

Hooks usage notes and examples

All hooks: Usage of environment variables in --args

All, except deprecated hooks: checkov, terraform_docs_replace

You can use environment variables for the --args section.
Note: You must use the ${ENV_VAR} definition, $ENV_VAR will not expand.

Config example:

- id: terraform_tflint
  args:
  - --args=--config=${CONFIG_NAME}.${CONFIG_EXT}
  - --args=--module

If for config above set up export CONFIG_NAME=.tflint; export CONFIG_EXT=hcl before pre-commit run, args will be expanded to --config=.tflint.hcl --module.

All hooks: Set env vars inside hook at runtime

All, except deprecated hooks: checkov, terraform_docs_replace

You can specify environment variables that will be passed to the hook at runtime.

Config example:

- id: terraform_validate
  args:
    - --env-vars=AWS_DEFAULT_REGION="us-west-2"
    - --env-vars=AWS_ACCESS_KEY_ID="anaccesskey"
    - --env-vars=AWS_SECRET_ACCESS_KEY="asecretkey"

All hooks: Disable color output

All, except deprecated hooks: checkov, terraform_docs_replace

To disable color output for all hooks, set PRE_COMMIT_COLOR=never var. Eg:

PRE_COMMIT_COLOR=never pre-commit run

checkov (deprecated) and terraform_checkov

checkov hook is deprecated, please use terraform_checkov.

Note that terraform_checkov runs recursively during -d . usage. That means, for example, if you change .tf file in repo root, all existing .tf files in repo will be checked.

1. You can specify custom arguments. E.g.:

   - id: terraform_checkov
     args:
       - --args=--quiet
       - --args=--skip-check CKV2_AWS_8

   Check all available arguments here.

For deprecated hook you need to specify each argument separately:

- id: checkov
  args: [
    "-d", ".",
    "--skip-check", "CKV2_AWS_8",
  ]

2. When you have multiple directories and want to run terraform_checkov in all of them and share a single config file - use the __GIT_WORKING_DIR__ placeholder. It will be replaced by terraform_checkov hooks with Git working directory (repo root) at run time. For example:

   - id: terraform_checkov
     args:
       - --args=--config-file __GIT_WORKING_DIR__/.checkov.yml

infracost_breakdown

infracost_breakdown executes infracost breakdown command and compare the estimated costs with those specified in the hook-config. infracost breakdown parses Terraform HCL code, and calls Infracost Cloud Pricing API (remote version or self-hosted version).

Unlike most other hooks, this hook triggers once if there are any changed files in the repository.

1. infracost_breakdown supports all infracost breakdown arguments (run infracost breakdown --help to see them). The following example only shows costs:

   - id: infracost_breakdown
     args:
       - --args=--path=./env/dev
     verbose: true # Always show costs

   Output

   Running in "env/dev"
   
   Summary: {
   "unsupportedResourceCounts": {
       "aws_sns_topic_subscription": 1
     }
   }
   
   Total Monthly Cost:        86.83 USD
   Total Monthly Cost (diff): 86.83 USD

2. Note that spaces are not allowed in --args, so you need to split it, like this:

   - id: infracost_breakdown
     args:
       - --args=--path=./env/dev
       - --args=--terraform-var-file="terraform.tfvars"
       - --args=--terraform-var-file="../terraform.tfvars"

3. (Optionally) Define cost constrains the hook should evaluate successfully in order to pass:

   - id: infracost_breakdown
     args:
       - --args=--path=./env/dev
       - --hook-config='.totalHourlyCost|tonumber > 0.1'
       - --hook-config='.totalHourlyCost|tonumber > 1'
       - --hook-config='.projects[].diff.totalMonthlyCost|tonumber != 10000'
       - --hook-config='.currency == "USD"'

   Output

   Running in "env/dev"
   Passed: .totalHourlyCost|tonumber > 0.1         0.11894520547945205 >  0.1
   Failed: .totalHourlyCost|tonumber > 1           0.11894520547945205 >  1
   Passed: .projects[].diff.totalMonthlyCost|tonumber !=10000              86.83 != 10000
   Passed: .currency == "USD"              "USD" == "USD"
   
   Summary: {
   "unsupportedResourceCounts": {
       "aws_sns_topic_subscription": 1
     }
   }
   
   Total Monthly Cost:        86.83 USD
   Total Monthly Cost (diff): 86.83 USD

   • Only one path per one hook (- id: infracost_breakdown) is allowed.
   • Set verbose: true to see cost even when the checks are passed.
   • Hook uses jq to process the cost estimation report returned by infracost breakdown command
   • Expressions defined as --hook-config argument should be in a jq-compatible format (e.g. .totalHourlyCost, .totalMonthlyCost) To study json output produced by infracost, run the command infracost breakdown -p PATH_TO_TF_DIR --format json, and explore it on jqplay.org.
   • Supported comparison operators: <, <=, ==, !=, >=, >.
   • Most useful paths and checks:
     • .totalHourlyCost (same as .projects[].breakdown.totalHourlyCost) - show total hourly infra cost
     • .totalMonthlyCost (same as .projects[].breakdown.totalMonthlyCost) - show total monthly infra cost
     • .projects[].diff.totalHourlyCost - show the difference in hourly cost for the existing infra and tf plan
     • .projects[].diff.totalMonthlyCost - show the difference in monthly cost for the existing infra and tf plan
     • .diffTotalHourlyCost (for Infracost version 0.9.12 or newer) or [.projects[].diff.totalMonthlyCost | select (.!=null) | tonumber] | add (for Infracost older than 0.9.12)

4. Docker usage. In docker build or docker run command:

   • You need to provide Infracost API key via -e INFRACOST_API_KEY=<your token>. By default, it is saved in ~/.config/infracost/credentials.yml
   • Set -e INFRACOST_SKIP_UPDATE_CHECK=true to skip the Infracost update check if you use this hook as part of your CI/CD pipeline.

terraform_docs

1. terraform_docs and terraform_docs_without_aggregate_type_defaults will insert/update documentation generated by terraform-docs framed by markers:

   <!-- BEGINNING OF PRE-COMMIT-TERRAFORM DOCS HOOK -->
   
   <!-- END OF PRE-COMMIT-TERRAFORM DOCS HOOK -->

   if they are present in README.md.

2. It is possible to pass additional arguments to shell scripts when using terraform_docs and terraform_docs_without_aggregate_type_defaults.

3. It is possible to automatically:

   • create a documentation file
   • extend existing documentation file by appending markers to the end of the file (see item 1 above)
   • use different filename for the documentation (default is README.md)

   - id: terraform_docs
     args:
       - --hook-config=--path-to-file=README.md        # Valid UNIX path. I.e. ../TFDOC.md or docs/README.md etc.
       - --hook-config=--add-to-existing-file=true     # Boolean. true or false
       - --hook-config=--create-file-if-not-exist=true # Boolean. true or false

4. You can provide any configuration available in terraform-docs as an argument to terraform_doc hook, for example:

   - id: terraform_docs
     args:
       - --args=--config=.terraform-docs.yml

   Note: Avoid use recursive.enabled: true in config file, that can cause unexpected behavior.

5. If you need some exotic settings, it can be done too. I.e. this one generates HCL files:

   - id: terraform_docs
     args:
       - tfvars hcl --output-file terraform.tfvars.model .

terraform_docs_replace (deprecated)

DEPRECATED. Will be merged in terraform_docs. See #248 for details.

terraform_docs_replace replaces the entire README.md rather than doing string replacement between markers. Put your additional documentation at the top of your main.tf for it to be pulled in. The optional --dest argument lets you change the filename that gets created/modified.

Example:

- id: terraform_docs_replace
  args:
    - --sort-by-required
    - --dest=TEST.md

terraform_fmt

1. terraform_fmt supports custom arguments so you can pass supported flags. Eg:

    - id: terraform_fmt
      args:
        - --args=-no-color
        - --args=-diff
        - --args=-write=false

terraform_providers_lock

1. The hook requires Terraform 0.14 or later.

2. The hook invokes two operations that can be really slow:

   • terraform init (in case .terraform directory is not initialised)
   • terraform providers lock

   Both operations require downloading data from remote Terraform registries, and not all of that downloaded data or meta-data is currently being cached by Terraform.

3. terraform_providers_lock supports custom arguments:

    - id: terraform_providers_lock
      args:
         - --args=-platform=windows_amd64
         - --args=-platform=darwin_amd64

4. It may happen that Terraform working directory (.terraform) already exists but not in the best condition (eg, not initialized modules, wrong version of Terraform, etc.). To solve this problem, you can find and delete all .terraform directories in your repository:

   echo "
   function rm_terraform {
       find . \( -iname ".terraform*" ! -iname ".terraform-docs*" \) -print0 | xargs -0 rm -r
   }
   " >>~/.bashrc
   
   # Reload shell and use `rm_terraform` command in the repo root

   terraform_providers_lock hook will try to reinitialize directories before running the terraform providers lock command.

5. terraform_providers_lock support passing custom arguments to its terraform init:

   - id: terraform_providers_lock
     args:
       - --tf-init-args=-upgrade

terraform_tflint

1. terraform_tflint supports custom arguments so you can enable module inspection, enable / disable rules, etc.

   Example:

   - id: terraform_tflint
     args:
       - --args=--module
       - --args=--enable-rule=terraform_documented_variables

2. When you have multiple directories and want to run tflint in all of them and share a single config file, it is impractical to hard-code the path to the .tflint.hcl file. The solution is to use the __GIT_WORKING_DIR__ placeholder which will be replaced by terraform_tflint hooks with Git working directory (repo root) at run time. For example:

   - id: terraform_tflint
     args:
       - --args=--config=__GIT_WORKING_DIR__/.tflint.hcl

terraform_tfsec

1. terraform_tfsec will consume modified files that pre-commit passes to it, so you can perform whitelisting of directories or files to run against via files pre-commit flag

   Example:

   - id: terraform_tfsec
     files: ^prd-infra/

   The above will tell pre-commit to pass down files from the prd-infra/ folder only such that the underlying tfsec tool can run against changed files in this directory, ignoring any other folders at the root level

2. To ignore specific warnings, follow the convention from the documentation.

   Example:

   resource "aws_security_group_rule" "my-rule" {
       type = "ingress"
       cidr_blocks = ["0.0.0.0/0"] #tfsec:ignore:AWS006
   }

3. terraform_tfsec supports custom arguments, so you can pass supported --no-color or --format (output), -e (exclude checks) flags:

    - id: terraform_tfsec
      args:
        - >
          --args=--format json
          --no-color
          -e aws-s3-enable-bucket-logging,aws-s3-specify-public-access-block

4. When you have multiple directories and want to run tfsec in all of them and share a single config file - use the __GIT_WORKING_DIR__ placeholder. It will be replaced by terraform_tfsec hooks with Git working directory (repo root) at run time. For example:

   - id: terraform_tfsec
     args:
       - --args=--config-file=__GIT_WORKING_DIR__/.tfsec.json

   Otherwise, will be used files that located in sub-folders:

   - id: terraform_tfsec
     args:
       - --args=--config-file=.tfsec.json

terraform_validate

1. terraform_validate supports custom arguments so you can pass supported -no-color or -json flags:

    - id: terraform_validate
      args:
        - --args=-json
        - --args=-no-color

2. terraform_validate also supports passing custom arguments to its terraform init:

   - id: terraform_validate
     args:
       - --tf-init-args=-lockfile=readonly

3. It may happen that Terraform working directory (.terraform) already exists but not in the best condition (eg, not initialized modules, wrong version of Terraform, etc.). To solve this problem, you can find and delete all .terraform directories in your repository:

   echo "
   function rm_terraform {
       find . \( -iname ".terraform*" ! -iname ".terraform-docs*" \) -print0 | xargs -0 rm -r
   }
   " >>~/.bashrc
   
   # Reload shell and use `rm_terraform` command in the repo root

   terraform_validate hook will try to reinitialize them before running the terraform validate command.

   Warning: If you use Terraform workspaces, DO NOT use this workaround (details). Wait to force-init option implementation.

4. terraform_validate in a repo with Terraform module, written using Terraform 0.15+ and which uses provider configuration_aliases (Provider Aliases Within Modules), errors out.

   When running the hook against Terraform code where you have provider configuration_aliases defined in a required_providers configuration block, terraform will throw an error like:

   Error: Provider configuration not present To work with its original provider configuration at provider["registry.terraform.io/hashicorp/aws"].<provider_alias> is required, but it has been removed. This occurs when a provider configuration is removed while objects created by that provider still exist in the state. Re-add the provider configuration to destroy , after which you can remove the provider configuration again.

   This is a known issue with Terraform and how providers are initialized in Terraform 0.15 and later. To work around this you can add an exclude parameter to the configuration of terraform_validate hook like this:

   - id: terraform_validate
     exclude: '^[^/]+$'

   This will exclude the root directory from being processed by this hook. Then add a subdirectory like "examples" or "tests" and put an example implementation in place that defines the providers with the proper aliases, and this will give you validation of your module through the example. If instead you are using this with multiple modules in one repository you'll want to set the path prefix in the regular expression, such as exclude: modules/offendingmodule/[^/]+$.

   Alternately, you can use terraform-config-inspect and use a variant of this script to generate a providers file at runtime:

   terraform-config-inspect --json . | jq -r '
     [.required_providers[].aliases]
     | flatten
     | del(.[] | select(. == null))
     | reduce .[] as $entry (
       {};
       .provider[$entry.name] //= [] | .provider[$entry.name] += [{"alias": $entry.alias}]
     )
   ' | tee aliased-providers.tf.json

   Save it as .generate-providers.sh in the root of your repository and add a pre-commit hook to run it before all other hooks, like so:

   - repos:
     - repo: local
       hooks:
         - id: generate-terraform-providers
            name: generate-terraform-providers
            require_serial: true
            entry: .generate-providers.sh
            language: script
            files: \.tf(vars)?$
            pass_filenames: false
   
     - repo: https://github.com/pre-commit/pre-commit-hooks
   [...]

   Note: The latter method will leave an "aliased-providers.tf.json" file in your repo. You will either want to automate a way to clean this up or add it to your .gitignore or both.

terraform_wrapper_module_for_each

terraform_wrapper_module_for_each generates module wrappers for Terraform modules (useful for Terragrunt where for_each is not supported). When using this hook without arguments it will create wrappers for the root module and all modules available in "modules" directory.

You may want to customize some of the options:

1. --module-dir=... - Specify a single directory to process. Values: "." (means just root module), "modules/iam-user" (a single module), or empty (means include all submodules found in "modules/*").
2. --module-repo-org=... - Module repository organization (e.g. "terraform-aws-modules").
3. --module-repo-shortname=... - Short name of the repository (e.g. "s3-bucket").
4. --module-repo-provider=... - Name of the repository provider (e.g. "aws" or "google").

Sample configuration:

- id: terraform_wrapper_module_for_each
  args:
    - --args=--module-dir=.   # Process only root module
    - --args=--dry-run        # No files will be created/updated
    - --args=--verbose        # Verbose output

If you use hook inside Docker:
The terraform_wrapper_module_for_each hook attempts to determine the module's short name to be inserted into the generated README.md files for the source URLs. Since the container uses a bind mount at a static location, it can cause this short name to be incorrect.
If the generated name is incorrect, set them by providing the module-repo-shortname option to the hook:

- id: terraform_wrapper_module_for_each
  args:
    - '--args=--module-repo-shortname=ec2-instance'

terrascan

1. terrascan supports custom arguments so you can pass supported flags like --non-recursive and --policy-type to disable recursive inspection and set the policy type respectively:

   - id: terrascan
     args:
       - --args=--non-recursive # avoids scan errors on subdirectories without Terraform config files
       - --args=--policy-type=azure

   See the terrascan run -h command line help for available options.

2. Use the --args=--verbose parameter to see the rule ID in the scaning output. Usuful to skip validations.

3. Use --skip-rules="ruleID1,ruleID2" parameter to skip one or more rules globally while scanning (e.g.: --args=--skip-rules="ruleID1,ruleID2").

4. Use the syntax #ts:skip=RuleID optional_comment inside a resource to skip the rule for that resource.

tfupdate

1. Out of the box tfupdate will pin the terraform version:

   - id: tfupdate
     name: Autoupdate Terraform versions

2. If you'd like to pin providers, etc., use custom arguments, i.e provider=PROVIDER_NAME:

   - id: tfupdate
     name: Autoupdate AWS provider versions
     args:
       - --args=provider aws # Will be pined to latest version
   
   - id: tfupdate
     name: Autoupdate Helm provider versions
     args:
       - --args=provider helm
       - --args=--version 2.5.0 # Will be pined to specified version

Check tfupdate usage instructions for other available options and usage examples.
No need to pass --recursive . as it is added automatically.

Docker Usage: File Permissions

A mismatch between the Docker container's user and the local repository file ownership can cause permission issues in the repository where pre-commit is run. The container runs as the root user by default, and uses a tools/entrypoint.sh script to assume a user ID and group ID if specified by the environment variable USERID.

The recommended command to run the Docker container is:

TAG=latest
docker run -e "USERID=$(id -u):$(id -g)" -v $(pwd):/lint -w /lint ghcr.io/antonbabenko/pre-commit-terraform:$TAG run -a

which uses your current session's user ID and group ID to set the variable in the run command. Without this setting, you may find files and directories owned by root in your local repository.

If the local repository is using a different user or group for permissions, you can modify the USERID to the user ID and group ID needed. Do not use the username or groupname in the environment variable, as it has no meaning in the container. You can get the current directory's owner user ID and group ID from the 3rd (user) and 4th (group) columns in ls output:

$ ls -aldn .
drwxr-xr-x 9 1000 1000 4096 Sep  1 16:23 .

Authors

This repository is managed by Anton Babenko with help from these awesome contributors:

License

MIT licensed. See LICENSE for full details.

Additional information for users from Russia and Belarus

• Russia has illegally annexed Crimea in 2014 and brought the war in Donbas followed by full-scale invasion of Ukraine in 2022.
• Russia has brought sorrow and devastations to millions of Ukrainians, killed hundreds of innocent people, damaged thousands of buildings, and forced several million people to flee.
• Putin khuylo!