Google Cloud Build sample Terraform deployment with rollback on failure

cloudbuild.yaml

steps:
  - name: 'hashicorp/terraform:1.0.4'
    dir: terraform
    args:
      - '-c'
      - |
        terraform init
    id: terraform init
    entrypoint: sh
  - name: 'hashicorp/terraform:1.0.4'
    dir: terraform
    args:
      - '-c'
      - |-
        if ! terraform apply -input=false -auto-approve ;  then 
          terraform destroy -input=false -auto-approve
          return 1
        fi
    id: terraform apply
    entrypoint: sh
logsBucket: 'gs://arrcuspoc-cb-logs'
options:
  logging: GCS_ONLY
timeout: 86400s

main.tf

terraform {
  required_providers {
    http = {
      source = "hashicorp/http"
      version = "3.2.1"
    }
    google = {
      source = "hashicorp/google"
      version = "4.53.1"
    }
    null = {
      source = "hashicorp/null"
      version = "3.2.1"
    }
  }
}

variable "project_id" {
  type = string
  description = "Google Cloud Project ID"
}

variable "region" {
  type = string
  description = "Google Cloud Region"
  default = "us-west1"
}

provider "google" {
  project = var.project_id
}

resource "google_compute_network" "vpc_network" {
  name                    = "my-custom-mode-network"
  auto_create_subnetworks = false
  mtu                     = 1460
}

resource "google_compute_subnetwork" "default" {
  name          = "my-custom-subnet"
  ip_cidr_range = "10.0.1.0/24"
  region        = var.region
  network       = google_compute_network.vpc_network.id
  depends_on   = [
      null_resource.example
  ] 
}

data "http" "example" {
  url = "https://checkpoint-api.hashicorp.com/v1/check/terraform"

  # Optional request headers
  request_headers = {
    Accept = "application/json"
  }
}

resource "null_resource" "example" {
  # On success, this will attempt to execute the true command in the
  # shell environment running terraform.
  # On failure, this will attempt to execute the false command in the
  # shell environment running terraform.
  provisioner "local-exec" {
      
    # Expected status_code is 200; if ommitted from contains list, the command will fail
    command = contains([201, 204], data.http.example.status_code)
  }
}