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

# VPC
resource "google_compute_network" "vpc" {
  name                    = "vpc"
  auto_create_subnetworks = false
}

# Sous-réseau
# front-end
resource "google_compute_subnetwork" "frontend" {
  name          = "frontend-subnet"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.1.0/24"
  region        = "europe-west1"
}

# back-end
resource "google_compute_subnetwork" "backend" {
  name          = "backend-subnet"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.2.0/24"
  region        = "europe-west1"
}

# data-base
resource "google_compute_subnetwork" "database" {
  name          = "database-subnet"
  network       = google_compute_network.vpc.id
  ip_cidr_range = "10.0.3.0/24"
  region        = "europe-west1"
}



# Règles de Pare-feu

#    - HTTP/HTTPS vers frontend
resource "google_compute_firewall" "allow_http" {
  name    = "allow-http"
  network = google_compute_network.vpc.id

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

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

#    - SSH vers toutes les instances
resource "google_compute_firewall" "allow_ssh" {
  name    = "allow-ssh"
  network = google_compute_network.vpc.id

  allow {
    protocol = "tcp"
    ports    = ["22"]
  }

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

#    - Port 8000 de frontend vers backend
resource "google_compute_firewall" "frontend_to_backend" {
  name    = "frontend-to-backend"
  network = google_compute_network.vpc.id

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

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


#    - Port 3306 de backend vers database
resource "google_compute_firewall" "backend_to_database" {
  name    = "backend-to-database"
  network = google_compute_network.vpc.id

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

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