Invoke-Terraform

A PowerShell module to run terraform.

GitHub Actions	PSGallery	License

Overview

Invoke-Terraform is a PowerShell module that downloads, validates binary authenticity and runs multiple versions of terraform. It is cross-platform with user preferences.

Installation

To install the module from the PowerShell Gallery:

Install-Module -Name Invoke-Terraform -Repository PSGallery

Usage

Install-Terraform -TFVersion 0.14.9

Invoke-Terraform

Invoke-Terraform -TFVersion 0.14.8

terraform -TFVersion 0.14.8 -version

Commands

Command	Description
Confirm-TerraformHashicorpKey	Confirm the HashiCorp Security Key in gpg.
Get-TerraformConfiguration	Get Invoke-Terraform configurations.
Get-TerraformStableBinary	Get the path for the current static installation of terraform binary.
Install-Terraform	Install a version of terraform.
Invoke-Terraform	Run terraform.
Set-TerraformAutoDownload	Set Invoke-Terraform to automatically download terraform if needed.
Set-TerraformAutoStableBinary	Set Set-TerraformVersion to automatically switch static installation of terraform binary.
Set-TerraformConfiguration	Set Invoke-Terraform configurations.
Set-TerraformStableBinary	Set version of static installation of terraform binary.
Set-TerraformSquelchChecksumWarning	Squelch checksum warnings.
Set-TerraformVersion	Change default version of terraform to invoke.
Switch-Terraform	Set-TerraformVersion alias.
Uninstall-Terraform	Uninstall a version of terraform.
terraform	Invoke-Terraform alias.

User Preferences

Name	Description
Path	Installation location for terraform binaries.
TFVersion	Preferred version of terraform.
ReleaseUrl	Defaults to https://releases.hashicorp.com/terraform
AutoDownload	Automatically download terraform when invoking if the binary is not installed. Defaults to false.
AutoStableBinary	Automatically switch the static binary to the TFVersion called with Set-TerraformVersion (ie Switch-Terraform). Defaults to false.

Verification

HashiCorp provides a few methods of verification for code authenticity. Invoke-Terraform uses checksum verification with gpg on all platforms and code signing verification with MacOS (starting ?) and Windows (starting with version 0.12.24).

The default behavior is to always run code signature verification every time terraform is run when supported and checksums when binaries are installed. By default HashiCorp PGP Key is import from keyserver.ubuntu.com. The following additional preferences may be used to validate the signatures provide by this module, and adjust the settings according to your security tolerance:

Name	Description
HashiCorpPGPKeyId	0x34365D9472D7468F
HashiCorpTeamIdentifier	D38WU7D763
HashiCorpWindowsThumbprint	35AB9FC834D217E9E7B1778FB1B97AF7C73792F2, '7868E4F55FD7B047CD8BF93FEA8C38509CFB5939'
PGPKeyServer	keyserver.ubuntu.com
SquelchChecksumWarning	Turn off warning from gpg when HashiCorp imported key has not be signed. Defaults to false.
SkipChecksum	Turn off release archive checksum verification via gpg. Defaults to false.
SkipCodeSignature	Turn off code signature verification. Defaults to false.

Other behavior

By default Invoke-Terraform searches the current working directory for the file .terraform-version. This file contains the preferred version of terraform. Store this file with your terraform project to seamlessly invoke the required version of terraform.

Best Practice

$ENV:Path, $PATH

It is recommended the terraform binary be removed from $ENV:Path. Even though the powershell alias overrides what is available in the Path, unexpected usage could occur if this module was not loaded. This eliminates the chance of running an unplanned version.

VSCode

If terraform is removed from your path as recommended, the vscode-terraform extension breaks. The Set-TerraformStableBinary has been added to provide a stable path name. Run Get-TerraformStableBinary to retrieve the path. Use the following example for vscode settings:

"terraform.languageServer": {
    "external": true,
    "pathToBinary": "",
    "args": [
        "serve",
        "-tf-exec=C:/users/pearcec/Documents/PowerShell/Modules/Invoke-Terraform/bin/terraform.exe",
    ],
    "maxNumberOfProblems": 100,
    "trace.server": "off"
}