Implementasi Aplikasi Multi-Tier

# Main Terraform Configuration
terraform {
  required_version = ">= 1.0"
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
    kubernetes = {
      source  = "hashicorp/kubernetes"
      version = "~> 2.0"
    }
  }

  backend "s3" {
    bucket = "multi-tier-tf-state"
    key    = "ecommerce-platform/terraform.tfstate"
    region = "us-east-1"
  }
}

# Provider Configuration
provider "aws" {
  region = var.aws_region
  default_tags {
    tags = {
      Environment = var.environment
      Project     = "multi-tier-app"
      ManagedBy   = "terraform"
    }
  }
}

# VPC Configuration dengan Multi-AZ
resource "aws_vpc" "main" {
  cidr_block           = var.vpc_cidr
  enable_dns_hostnames = true
  enable_dns_support   = true

  tags = {
    Name = "${var.cluster_name}-vpc"
  }
}

# Public Subnets untuk Load Balancer
resource "aws_subnet" "public" {
  count = length(var.public_subnet_cidrs)
  
  vpc_id                  = aws_vpc.main.id
  cidr_block              = var.public_subnet_cidrs[count.index]
  availability_zone       = data.aws_availability_zones.available.names[count.index]
  map_public_ip_on_launch = true

  tags = {
    Name = "${var.cluster_name}-public-${count.index + 1}"
    "kubernetes.io/role/elb" = "1"
  }
}

apiVersion: apps/v1
kind: Deployment
metadata:
  name: frontend
  namespace: ecommerce-production
  labels:
    app: frontend
    tier: presentation
spec:
  replicas: 3
  selector:
    matchLabels:
      app: frontend
  template:
    metadata:
      labels:
        app: frontend
        tier: presentation
    spec:
      containers:
      - name: frontend
        image: your-registry/frontend:1.0.0
        ports:
        - containerPort: 80
        env:
        - name: API_BASE_URL
          value: "http://api-gateway:8000"
        resources:
          requests:
            memory: "256Mi"
            cpu: "100m"
          limits:
            memory: "512Mi"
            cpu: "200m"