terraform

name	terraform
description	Terraform infrastructure as code for provisioning, modules, state management, and workspaces. Use when user asks to "create infrastructure", "write Terraform", "manage state", "create module", "import resource", "plan changes", or any IaC tasks.

Terraform

Infrastructure as Code with Terraform.

Core Workflow

# Initialize (download providers)
terraform init

# Preview changes
terraform plan
terraform plan -out=tfplan          # Save plan

# Apply changes
terraform apply
terraform apply tfplan              # Apply saved plan
terraform apply -auto-approve       # Skip confirmation

# Destroy resources
terraform destroy
terraform destroy -target=aws_instance.web

# Format code
terraform fmt
terraform fmt -recursive

# Validate configuration
terraform validate

# Show current state
terraform show
terraform state list
terraform state show aws_instance.web

Basic Configuration

# main.tf
terraform {
  required_version = ">= 1.5"
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }

  backend "s3" {
    bucket = "my-terraform-state"
    key    = "prod/terraform.tfstate"
    region = "us-east-1"
  }
}

provider "aws" {
  region = var.region
}

Variables

# variables.tf
variable "region" {
  description = "AWS region"
  type        = string
  default     = "us-east-1"
}

variable "instance_type" {
  description = "EC2 instance type"
  type        = string
  default     = "t3.micro"
}

variable "tags" {
  description = "Resource tags"
  type        = map(string)
  default = {
    Environment = "dev"
    ManagedBy   = "terraform"
  }
}

variable "allowed_cidrs" {
  description = "Allowed CIDR blocks"
  type        = list(string)
  default     = ["0.0.0.0/0"]
}