Terraform 프로비저닝과 배포 전략

provider "aws" {
  region = "ap-northeast-2"
}

resource "aws_instance" "web" {
  ami           = "ami-0abcdef1234567890"
  instance_type = "t2.micro"
  tags = {
    Name = "Terraform-Web"
  }
}

resource "aws_vpc" "main" {
  cidr_block = "10.0.0.0/16"
  tags = {
    Name = "main-vpc"
  }
}

resource "aws_db_instance" "default" {
  engine         = "mysql"
  instance_class = "db.t3.micro"
  name           = "mydb"
  username       = "admin"
  password       = "password"
  allocated_storage = 20
  skip_final_snapshot = true
}

module "eks" {
  source          = "terraform-aws-modules/eks/aws"
  cluster_name    = "my-eks-cluster"
  cluster_version = "1.29"
  subnets         = ["subnet-abc", "subnet-def"]
  vpc_id          = "vpc-123456"
}

terraform destroy

terraform plan -out=tfplan
terraform apply tfplan

resource "aws_lb_listener_rule" "green" {
  # Green target group으로 전환
}

# 처음엔 EC2 1대만 신규 배포 후 점진 확장
count = var.deploy_stage == "canary" ? 1 : 3

Git Repo (Terraform 코드)
   ↓
CI (Terraform fmt, validate, plan)
   ↓
CD (apply 승인, 상태 저장 백엔드 연동)

1. Git Push
2. GitHub Actions / GitLab CI:
    - terraform fmt
    - terraform validate
    - terraform plan -out=plan.out
    - manual approve step
    - terraform apply plan.out

name: Terraform CI/CD

on:
  push:
    branches: [ "main" ]

jobs:
  terraform:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v3
    - name: Setup Terraform
      uses: hashicorp/setup-terraform@v2

    - name: Terraform Init
      run: terraform init

    - name: Terraform Plan
      run: terraform plan -out=tfplan

    - name: Terraform Apply
      if: github.ref == 'refs/heads/main'
      run: terraform apply -auto-approve tfplan