Remove App Engine from Terraform (#2269)

Fun fact: You can't actually remove App Engine from a Google Cloud
project (without deleting and re-creating the whole project).

I've experimented with this on a test project - deleting the App Engine
resource doesn't seem to do anything besides making Terraform stop
tracking it. We can manually disable the App Engine application in the
GCP UI, which won't delete our data.

Author: michaelkedar

deployment/terraform/modules/osv/gcp_apis.tf

@@ -80,12 +80,6 @@ resource "google_project_service" "service_usage" {
   disable_on_destroy = false
 }
 
-resource "google_project_service" "app_engine" {
-  project            = var.project_id
-  service            = "appengine.googleapis.com"
-  disable_on_destroy = false
-}
-
 resource "google_project_service" "resource_manager" {
   project            = var.project_id
   service            = "cloudresourcemanager.googleapis.com"

deployment/terraform/modules/osv/main.tf

@@ -1,13 +1,5 @@
 # osv.dev terraform configuration
 
-# App Engine
-resource "google_app_engine_application" "app" {
-  project       = var.project_id
-  location_id   = "us-west2"
-  database_type = "CLOUD_DATASTORE_COMPATIBILITY"
-
-}
-
 # Datastore
 resource "google_firestore_database" "datastore" {
   project     = var.project_id
@@ -16,6 +8,7 @@ resource "google_firestore_database" "datastore" {
   type        = "DATASTORE_MODE"
 
   lifecycle {
+    # Destroying the resource doesn't seem to delete the database
     prevent_destroy = true
   }
 }
@@ -193,13 +186,3 @@ resource "google_project_iam_member" "deployment_service" {
   role    = "roles/editor"
   member  = "serviceAccount:${google_service_account.deployment_service.email}"
 }
-
-data "google_app_engine_default_service_account" "default" {
-  project = var.project_id
-}
-
-resource "google_project_iam_member" "app_engine_service" {
-  project = var.project_id
-  role    = "roles/editor"
-  member  = "serviceAccount:${data.google_app_engine_default_service_account.default.email}"
-}