terraform-provider-assert

Custom provider to enable assert like functionality in terraform.

Example usage:
Throw exception if user is not using workspaces ( current workspace is default )
main.tf

data "assert_test" "workspace" {
    test = terraform.workspace != "default" // must return TRUE or FALSE
    throw = "default workspace is not valid in this project" // must be of type string
}

there is no need to explicitly initialize provider in your .tf files with the provider "name" {} block, just use data source directly.

dynamic vs static variables in test condition

Terraform validates values at two stages:

• during validation ( static variables passed to terraform or computed during validation )
• during apply ( dynamic variables known after resource is created )

terraform-provider-assert works in both stages, however, if you pass condition based on value computed from resource data it will only throw during apply stage.

Installation

terraform < 13.0

Terraform reads the custom provider binaries from two locations:

• current location where terraform main.tf is run from
• and
  • %APPDATA%\terraform.d\plugins\windows_amd64 on Windows
  • ~/.terraform.d/plugins/darwin_amd64 on Mac
  • ~/.terraform.d/plugins/linux_amd64 on Linux

Place the binary in plugins directory for your platform and run terraform init in your project to load custom plugin configuration.

terraform >= 13.0

from version 13+ the way terraform fetches providers has changed. In your main configuration add required_providers block:

terraform {
  required_providers {
    assert = {
      source  = "github.com/bwoznicki/assert"
    }
  }
}

Implicitly terraform still checks your local dir eg. ~/terraform.d/plugins but you must place the binary in a sligltly different path eg. .terraform.d/plugins/github.com/bwoznicki/assert/0.0.1/linux_amd64/ for linux.
You can also specify a custom path where your local providers are fetched from using ~/terraformrc or ~/terraform.rc for more info pleace check official documentation https://www.terraform.io/docs/cli/config/config-file.html#provider-installation