Revert Drop gcp_clusters table

changelogs/unreleased/drop-gcp-cluster-table.yml

----
-title: Drop gcp_clusters table
-merge_request: 22713
-author:
-type: other

db/migrate/20181031190559_drop_gcp_clusters_table.rb

-# frozen_string_literal: true
-
-class DropGcpClustersTable < ActiveRecord::Migration
-  include Gitlab::Database::MigrationHelpers
-
-  DOWNTIME = false
-
-  def up
-    drop_table :gcp_clusters
-  end
-
-  def down
-    create_table :gcp_clusters do |t|
-      # Order columns by best align scheme
-      t.references :project, null: false, index: { unique: true }, foreign_key: { on_delete: :cascade }
-      t.references :user, foreign_key: { on_delete: :nullify }
-      t.references :service, foreign_key: { on_delete: :nullify }
-      t.integer :status
-      t.integer :gcp_cluster_size, null: false
-
-      # Timestamps
-      t.datetime_with_timezone :created_at, null: false
-      t.datetime_with_timezone :updated_at, null: false
-
-      # Enable/disable
-      t.boolean :enabled, default: true
-
-      # General
-      t.text :status_reason
-
-      # k8s integration specific
-      t.string :project_namespace
-
-      # Cluster details
-      t.string :endpoint
-      t.text :ca_cert
-      t.text :encrypted_kubernetes_token
-      t.string :encrypted_kubernetes_token_iv
-      t.string :username
-      t.text :encrypted_password
-      t.string :encrypted_password_iv
-
-      # GKE
-      t.string :gcp_project_id, null: false
-      t.string :gcp_cluster_zone, null: false
-      t.string :gcp_cluster_name, null: false
-      t.string :gcp_machine_type
-      t.string :gcp_operation_id
-      t.text :encrypted_gcp_token
-      t.string :encrypted_gcp_token_iv
-    end
-  end
-end

db/schema.rb

@@ -919,6 +919,35 @@ ActiveRecord::Schema.define(version: 20181101144347) do
 
   add_index "forked_project_links", ["forked_to_project_id"], name: "index_forked_project_links_on_forked_to_project_id", unique: true, using: :btree
 
+  create_table "gcp_clusters", force: :cascade do |t|
+    t.integer "project_id", null: false
+    t.integer "user_id"
+    t.integer "service_id"
+    t.integer "status"
+    t.integer "gcp_cluster_size", null: false
+    t.datetime_with_timezone "created_at", null: false
+    t.datetime_with_timezone "updated_at", null: false
+    t.boolean "enabled", default: true
+    t.text "status_reason"
+    t.string "project_namespace"
+    t.string "endpoint"
+    t.text "ca_cert"
+    t.text "encrypted_kubernetes_token"
+    t.string "encrypted_kubernetes_token_iv"
+    t.string "username"
+    t.text "encrypted_password"
+    t.string "encrypted_password_iv"
+    t.string "gcp_project_id", null: false
+    t.string "gcp_cluster_zone", null: false
+    t.string "gcp_cluster_name", null: false
+    t.string "gcp_machine_type"
+    t.string "gcp_operation_id"
+    t.text "encrypted_gcp_token"
+    t.string "encrypted_gcp_token_iv"
+  end
+
+  add_index "gcp_clusters", ["project_id"], name: "index_gcp_clusters_on_project_id", unique: true, using: :btree
+
   create_table "gpg_key_subkeys", force: :cascade do |t|
     t.integer "gpg_key_id", null: false
     t.binary "keyid"
@@ -2402,6 +2431,9 @@ ActiveRecord::Schema.define(version: 20181101144347) do
   add_foreign_key "fork_network_members", "projects", on_delete: :cascade
   add_foreign_key "fork_networks", "projects", column: "root_project_id", name: "fk_e7b436b2b5", on_delete: :nullify
   add_foreign_key "forked_project_links", "projects", column: "forked_to_project_id", name: "fk_434510edb0", on_delete: :cascade
+  add_foreign_key "gcp_clusters", "projects", on_delete: :cascade
+  add_foreign_key "gcp_clusters", "services", on_delete: :nullify
+  add_foreign_key "gcp_clusters", "users", on_delete: :nullify
   add_foreign_key "gpg_key_subkeys", "gpg_keys", on_delete: :cascade
   add_foreign_key "gpg_keys", "users", on_delete: :cascade
   add_foreign_key "gpg_signatures", "gpg_key_subkeys", on_delete: :nullify