three-tier-gke/infra/network.tf

/**
Copyright 2023 Google LLC

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

module "vpc" {
  source       = "terraform-google-modules/network/google"
  version      = "~> 5.1.0"
  project_id   = var.project_id
  network_name = "${var.application_name}-vpc"
  routing_mode = "GLOBAL"

  subnets = [
    {
      subnet_name           = "subnet-${var.region}"
      subnet_ip             = local.cluster_ip_ranges.nodes
      subnet_region         = var.region
      subnet_private_access = true
    },

    {
      subnet_name   = "proxy-only-subnet"
      subnet_ip     = "10.129.0.0/23"
      subnet_region = var.region
      purpose       = "REGIONAL_MANAGED_PROXY"
      role          = "ACTIVE"
    },
  ]

  secondary_ranges = {
    "subnet-${var.region}" = [
      {
        range_name    = "pods"
        ip_cidr_range = local.cluster_ip_ranges.pods
      },
      {
        range_name    = "services"
        ip_cidr_range = local.cluster_ip_ranges.services
      },
    ]
  }
}

resource "google_compute_router" "nat_router" {
  name    = "${module.vpc.network_name}-nat-router"
  network = module.vpc.network_self_link
  region  = var.region

  bgp {
    asn = 64514
  }
}

resource "google_compute_router_nat" "nat_gateway" {
  name                               = "${module.vpc.network_name}-nat-gw"
  router                             = google_compute_router.nat_router.name
  region                             = google_compute_router.nat_router.region
  nat_ip_allocate_option             = "AUTO_ONLY"
  source_subnetwork_ip_ranges_to_nat = "ALL_SUBNETWORKS_ALL_IP_RANGES"

  log_config {
    enable = true
    filter = "ERRORS_ONLY"
  }
}

resource "google_compute_global_address" "service_range" {
  name          = "service-networking-address"
  purpose       = "VPC_PEERING"
  address_type  = "INTERNAL"
  address       = "10.200.0.0"
  prefix_length = 16
  network       = module.vpc.network_name
}

resource "google_service_networking_connection" "service_networking" {
  network                 = module.vpc.network_id
  service                 = "servicenetworking.googleapis.com"
  reserved_peering_ranges = [google_compute_global_address.service_range.name]
}