Add cluster_id to deployments table as an FK

We nullify when cluster is deleted as we want to keep the deployment
record around.

Add cluster as an optional association

We will have only cluster for deployments where the build deploys to a
kubernetes cluster

2 files changed, 30 insertions, 0 deletions

diff --git a/db/migrate/20190623212503_add_cluster_id_to_deployments.rb b/db/migrate/20190623212503_add_cluster_id_to_deployments.rb
new file mode 100644
index 00000000000..cd0c4191568
--- /dev/null
+++ b/db/migrate/20190623212503_add_cluster_id_to_deployments.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddClusterIdToDeployments < ActiveRecord::Migration[5.1]
+  DOWNTIME = false
+
+  def change
+    add_column :deployments, :cluster_id, :integer
+  end
+end
diff --git a/db/migrate/20190627051902_add_cluster_id_index_fk_to_deployments.rb b/db/migrate/20190627051902_add_cluster_id_index_fk_to_deployments.rb
new file mode 100644
index 00000000000..f41e5c80269
--- /dev/null
+++ b/db/migrate/20190627051902_add_cluster_id_index_fk_to_deployments.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class AddClusterIdIndexFkToDeployments < ActiveRecord::Migration[5.1]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :deployments, :cluster_id
+
+    add_concurrent_foreign_key :deployments, :clusters, column: :cluster_id, on_delete: :nullify
+  end
+
+  def down
+    remove_foreign_key :deployments, :clusters
+
+    remove_concurrent_index :deployments, :cluster_id
+  end
+end