Use separate Kubernetes namespaces per environment

Kubernetes deployments on new clusters will now have
a separate namespace per project environment, instead
of sharing a single namespace for the project.

Behaviour of existing clusters is unchanged.

All new functionality is controlled by the
:kubernetes_namespace_per_environment feature flag,
which is safe to enable/disable at any time.

1 files changed, 18 insertions, 0 deletions

diff --git a/db/migrate/20190712040412_index_clusters_kubernetes_namespaces_on_environment_id.rb b/db/migrate/20190712040412_index_clusters_kubernetes_namespaces_on_environment_id.rb
new file mode 100644
index 00000000000..23082492091
--- /dev/null
+++ b/db/migrate/20190712040412_index_clusters_kubernetes_namespaces_on_environment_id.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+class IndexClustersKubernetesNamespacesOnEnvironmentId < ActiveRecord::Migration[5.1]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+  INDEX_NAME = 'index_kubernetes_namespaces_on_cluster_project_environment_id'
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :clusters_kubernetes_namespaces, [:cluster_id, :project_id, :environment_id], unique: true, name: INDEX_NAME
+  end
+
+  def down
+    remove_concurrent_index :clusters_kubernetes_namespaces, name: INDEX_NAME
+  end
+end