but3-iac/tp-cloud/terraform/modules/network/main.tf

# Provider
provider "google" {
  project = var.project_name
  region  = var.region
}

# VPC
resource "google_compute_network" "vpc" {
  name                    = "${var.project_name}-vpc"
  auto_create_subnetworks = false
}

# Sous-réseau
resource "google_compute_subnetwork" "frontend" {
  name          = "frontend"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.1.0/24"
  region        = var.region
}

resource "google_compute_subnetwork" "backend" {
  name          = "backend"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.2.0/24"
  region        = var.region
}

resource "google_compute_subnetwork" "database" {
  name          = "database"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.3.0/24"
  region        = var.region
}

# Pare-feu
resource "google_compute_firewall" "allow_http" {
  name      = "allow-http"
  network   = google_compute_network.vpc.id
  direction = "INGRESS"

  allow {
    protocol = "tcp"
    ports    = ["80", "443"]
  }

  source_ranges = ["0.0.0.0/0"]
  target_tags   = ["frontend", "ssh"]
}

resource "google_compute_firewall" "backend-connect" {
  name      = "backend-connect"
  network   = google_compute_network.vpc.id
  direction = "INGRESS"

  allow {
    protocol = "tcp"
    ports    = ["8000"]
  }

  source_tags = ["frontend"]
  target_tags = ["backend", "ssh"]
}

resource "google_compute_firewall" "database-connect" {
  name      = "database-connect"
  network   = google_compute_network.vpc.id
  direction = "INGRESS"

  allow {
    protocol = "tcp"
    ports    = ["3306"]
  }

  source_tags = ["backend"]
  target_tags = ["database", "ssh"]
}