Terraform at Scale + Advanced Concepts

🎯 Lab Goal You will build a modular Terraform project that: Creates IAM users + EC2 Uses for_each , count , zipmap Demonstrates lifecycle rules Shows dependency handling Simulates scale practices Uses targeting & refresh control 🧱 STEP 1 — Project Structure (Scaling Best Practice) terraform-scale-lab/ │ ├── iam/ │ └── main.tf │ ├── ec2/ │ └── main.tf │ ├── shared/ │ └── variables.tf │ └── root/ └── main.tf ✅ This simulates: Large infra split into modules Reduces API calls Used in real companies 🧩 STEP 2 — Shared Variables (Object + Map + Set) 📄 shared/variables.tf variable "users" { type = set ( string ) default = [ "alice" , "bob" , "john" ] } variable "amis" { type = map ( string ) default = { dev = "ami-123456" prod = "ami-654321" } } variable "instance_config" { type = object ({ instance_type = string count = number }) default = { instance_type = "t2.micro" count = 2 } } ✅ Covers: set map object 👤 STEP 3 — IAM Module (for_each + zipmap) 📄 iam/main.tf # Create IAM users using for_ea