From f9fc68024c7b40bdc53f64dcdef929671153432e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?St=C3=A9phane=20Meny?= <smeny@users.noreply.github.com>
Date: Wed, 26 Jan 2022 15:38:17 +0000
Subject: [PATCH] Ensures DB migration only happens on first instance

---
 lib/tasks/cf.rake | 12 ++++++++++++
 manifest.yml      |  4 ++--
 2 files changed, 14 insertions(+), 2 deletions(-)
 create mode 100644 lib/tasks/cf.rake

diff --git a/lib/tasks/cf.rake b/lib/tasks/cf.rake
new file mode 100644
index 000000000..ad7dc0c6d
--- /dev/null
+++ b/lib/tasks/cf.rake
@@ -0,0 +1,12 @@
+namespace :cf do
+  desc "Only run on the first application instance"
+  task on_first_instance: :environment do
+    instance_index = -1
+    begin
+      instance_index = JSON.parse(ENV["VCAP_APPLICATION"])["instance_index"]
+    rescue StandardError
+      nil
+    end
+    exit(0) unless instance_index.zero?
+  end
+end
diff --git a/manifest.yml b/manifest.yml
index 154e816ef..5935f2495 100644
--- a/manifest.yml
+++ b/manifest.yml
@@ -1,10 +1,10 @@
 ---
 defaults: &defaults
   buildpacks:
-    - https://github.com/cloudfoundry/ruby-buildpack.git
+    - ruby_buildpack
   processes:
     - type: web
-      command: rake db:migrate && bin/rails server
+      command: bundle exec rake cf:on_first_instance db:migrate && bin/rails server
       instances: 2
       memory: 512M