Add health check (#253)

config/routes.rb

@@ -9,6 +9,8 @@ Rails.application.routes.draw do
     get "confirmations/reset", to: "auth/passwords#reset_confirmation"
   end
 
+  get "/health", to: ->(_) { [204, {}, [nil]] }
+
   # For details on the DSL available within this file, see https://guides.rubyonrails.org/routing.html
   ActiveAdmin.routes(self)
 

manifest.yml

@@ -7,6 +7,8 @@ defaults: &defaults
       command: bundle exec rake cf:on_first_instance db:migrate && bin/rails server
       instances: 2
       memory: 512M
+  health-check-type: http
+  health-check-http-endpoint: /health
 
 applications:
   - name: dluhc-core-staging

spec/features/test_spec.rb

@@ -4,4 +4,9 @@ RSpec.describe "Test Features" do
     visit("/")
     expect(page).to have_content("Submit social housing lettings and sales data (CORE)")
   end
+
+  it "Responds to a health check" do
+    visit("/health")
+    expect(page).to have_http_status(204)
+  end
 end