Automatizza la configurazione di Cloud CDN con Terraform

Usa l'esempio seguente per eseguire il deployment del backend di un Application Load Balancer esterno di esempio con Cloud CDN abilitato.

Se non hai mai utilizzato Terraform per Google Cloud, consulta la guida introduttiva a Terraform.

MIG e intestazioni personalizzate

Puoi utilizzare le risorse Terraform per generare un bilanciatore del carico HTTP esterno con un servizio di backend Cloud CDN e intestazioni di richieste e risposte personalizzate.

Per informazioni sulla configurazione del bilanciatore del carico, consulta la guida alla configurazione principale.

# VPC
resource "google_compute_network" "default" {
  name                    = "l7-xlb-network"
  provider                = google-beta
  auto_create_subnetworks = false
}

# backend subnet
resource "google_compute_subnetwork" "default" {
  name          = "l7-xlb-subnet"
  provider      = google-beta
  ip_cidr_range = "10.0.1.0/24"
  region        = "us-central1"
  network       = google_compute_network.default.id
}

# reserved IP address
resource "google_compute_global_address" "default" {
  provider = google-beta
  name     = "l7-xlb-static-ip"
}

# forwarding rule
resource "google_compute_global_forwarding_rule" "default" {
  name                  = "l7-xlb-forwarding-rule"
  provider              = google-beta
  ip_protocol           = "TCP"
  load_balancing_scheme = "EXTERNAL"
  port_range            = "80"
  target                = google_compute_target_http_proxy.default.id
  ip_address            = google_compute_global_address.default.id
}

# http proxy
resource "google_compute_target_http_proxy" "default" {
  name     = "l7-xlb-target-http-proxy"
  provider = google-beta
  url_map  = google_compute_url_map.default.id
}

# url map
resource "google_compute_url_map" "default" {
  name            = "l7-xlb-url-map"
  provider        = google-beta
  default_service = google_compute_backend_service.default.id
}

# backend service with custom request and response headers
resource "google_compute_backend_service" "default" {
  name                    = "l7-xlb-backend-service"
  provider                = google-beta
  protocol                = "HTTP"
  port_name               = "my-port"
  load_balancing_scheme   = "EXTERNAL"
  timeout_sec             = 10
  enable_cdn              = true
  custom_request_headers  = ["X-Client-Geo-Location: {client_region_subdivision}, {client_city}"]
  custom_response_headers = ["X-Cache-Hit: {cdn_cache_status}"]
  health_checks           = [google_compute_health_check.default.id]
  backend {
    group           = google_compute_instance_group_manager.default.instance_group
    balancing_mode  = "UTILIZATION"
    capacity_scaler = 1.0
  }
}

# instance template
resource "google_compute_instance_template" "default" {
  name         = "l7-xlb-mig-template"
  provider     = google-beta
  machine_type = "e2-small"
  tags         = ["allow-health-check"]

  network_interface {
    network    = google_compute_network.default.id
    subnetwork = google_compute_subnetwork.default.id
    access_config {
      # add external ip to fetch packages
    }
  }
  disk {
    source_image = "debian-cloud/debian-10"
    auto_delete  = true
    boot         = true
  }

  # install nginx and serve a simple web page
  metadata = {
    startup-script = <<-EOF1
      #! /bin/bash
      set -euo pipefail

      export DEBIAN_FRONTEND=noninteractive
      apt-get update
      apt-get install -y nginx-light jq

      NAME=$(curl -H "Metadata-Flavor: Google" "http://metadata.google.internal/computeMetadata/v1/instance/hostname")
      IP=$(curl -H "Metadata-Flavor: Google" "http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/ip")
      METADATA=$(curl -f -H "Metadata-Flavor: Google" "http://metadata.google.internal/computeMetadata/v1/instance/attributes/?recursive=True" | jq 'del(.["startup-script"])')

      cat <<EOF > /var/www/html/index.html
      <pre>
      Name: $NAME
      IP: $IP
      Metadata: $METADATA
      </pre>
      EOF
    EOF1
  }
  lifecycle {
    create_before_destroy = true
  }
}

# health check
resource "google_compute_health_check" "default" {
  name     = "l7-xlb-hc"
  provider = google-beta
  http_health_check {
    port_specification = "USE_SERVING_PORT"
  }
}

# MIG
resource "google_compute_instance_group_manager" "default" {
  name     = "l7-xlb-mig1"
  provider = google-beta
  zone     = "us-central1-c"
  named_port {
    name = "http"
    port = 8080
  }
  version {
    instance_template = google_compute_instance_template.default.id
    name              = "primary"
  }
  base_instance_name = "vm"
  target_size        = 2
}

# allow access from health check ranges
resource "google_compute_firewall" "default" {
  name          = "l7-xlb-fw-allow-hc"
  provider      = google-beta
  direction     = "INGRESS"
  network       = google_compute_network.default.id
  source_ranges = ["130.211.0.0/22", "35.191.0.0/16"]
  allow {
    protocol = "tcp"
  }
  target_tags = ["allow-health-check"]
}