Add support for DAG

This implements the support for `needs:` keyword
as part of GitLab CI. That makes some of the jobs
to be run out of order.

2 files changed, 28 insertions, 1 deletions

diff --git a/db/migrate/20190731084415_add_build_need.rb b/db/migrate/20190731084415_add_build_need.rb
new file mode 100644
index 00000000000..45b8abb480d
--- /dev/null
+++ b/db/migrate/20190731084415_add_build_need.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddBuildNeed < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    create_table :ci_build_needs, id: :serial do |t|
+      t.integer :build_id, null: false
+      t.text :name, null: false
+
+      t.index [:build_id, :name], unique: true
+      t.foreign_key :ci_builds, column: :build_id, on_delete: :cascade
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 6f5fc6c65eb..df2662b770b 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2019_07_29_090456) do
+ActiveRecord::Schema.define(version: 2019_07_31_084415) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -454,6 +454,12 @@ ActiveRecord::Schema.define(version: 2019_07_29_090456) do
     t.index ["namespace_id"], name: "index_chat_teams_on_namespace_id", unique: true
   end
 
+  create_table "ci_build_needs", id: :serial, force: :cascade do |t|
+    t.integer "build_id", null: false
+    t.text "name", null: false
+    t.index ["build_id", "name"], name: "index_ci_build_needs_on_build_id_and_name", unique: true
+  end
+
   create_table "ci_build_trace_chunks", force: :cascade do |t|
     t.integer "build_id", null: false
     t.integer "chunk_index", null: false
@@ -3635,6 +3641,7 @@ ActiveRecord::Schema.define(version: 2019_07_29_090456) do
   add_foreign_key "boards", "namespaces", column: "group_id", on_delete: :cascade
   add_foreign_key "boards", "projects", name: "fk_f15266b5f9", on_delete: :cascade
   add_foreign_key "chat_teams", "namespaces", on_delete: :cascade
+  add_foreign_key "ci_build_needs", "ci_builds", column: "build_id", on_delete: :cascade
   add_foreign_key "ci_build_trace_chunks", "ci_builds", column: "build_id", on_delete: :cascade
   add_foreign_key "ci_build_trace_section_names", "projects", on_delete: :cascade
   add_foreign_key "ci_build_trace_sections", "ci_build_trace_section_names", column: "section_name_id", name: "fk_264e112c66", on_delete: :cascade