Use worker to destroy namespaceless projects in post-deploy

Destroying projects can be very time consuming. So instead of destroying them in
the post-deploy, just schedule them and make Sidekiq do the hard work.

They are scheduled in batches of 5000 records. This way the number of database
requests is limited while also the amount data read to memory is limited.

3 files changed, 105 insertions, 72 deletions

diff --git a/spec/migrations/clean_up_pending_delete_projects_spec.rb b/spec/migrations/clean_up_pending_delete_projects_spec.rb
deleted file mode 100644
index a7c13f91245..00000000000
--- a/spec/migrations/clean_up_pending_delete_projects_spec.rb
+++ /dev/null
@@ -1,72 +0,0 @@
-# encoding: utf-8
-
-require 'spec_helper'
-require Rails.root.join('db', 'post_migrate', '20170502101023_clean_up_pending_delete_projects.rb')
-
-describe CleanUpPendingDeleteProjects do
-  let(:migration) { described_class.new }
-  let!(:admin) { create(:admin) }
-  let!(:project) { create(:empty_project, pending_delete: true) }
-
-  describe '#up' do
-    it 'only cleans up pending delete projects' do
-      create(:empty_project)
-
-      expect do
-        migration.up
-      end.to change { Project.unscoped.count }.by(-1)
-    end
-
-    it "truncates the project's team" do
-      project.add_master(admin)
-
-      expect_any_instance_of(ProjectTeam).to receive(:truncate)
-
-      migration.up
-    end
-
-    it 'calls Project#destroy!' do
-      expect_any_instance_of(Project).to receive(:destroy!)
-
-      migration.up
-    end
-
-    it 'does not do anything in Project#remove_pages method' do
-      expect(Gitlab::PagesTransfer).not_to receive(:new)
-
-      migration.up
-    end
-
-    context 'project not a fork of another project' do
-      it "doesn't call unlink_fork" do
-        expect(migration).not_to receive(:unlink_fork)
-
-        migration.up
-      end
-    end
-
-    context 'project forked from another' do
-      let!(:parent_project) { create(:empty_project) }
-
-      before do
-        create(:forked_project_link, forked_to_project: project, forked_from_project: parent_project)
-      end
-
-      it 'closes open merge requests' do
-        project.update_attribute(:pending_delete, false) # needed to create the MR
-        merge_request = create(:merge_request, source_project: project, target_project: parent_project)
-        project.update_attribute(:pending_delete, true)
-
-        migration.up
-
-        expect(merge_request.reload).to be_closed
-      end
-
-      it 'destroys the link' do
-        migration.up
-
-        expect(parent_project.forked_project_links).to be_empty
-      end
-    end
-  end
-end
diff --git a/spec/migrations/cleanup_namespaceless_pending_delete_projects_spec.rb b/spec/migrations/cleanup_namespaceless_pending_delete_projects_spec.rb
new file mode 100644
index 00000000000..cee12d521dc
--- /dev/null
+++ b/spec/migrations/cleanup_namespaceless_pending_delete_projects_spec.rb
@@ -0,0 +1,24 @@
+require 'spec_helper'
+require Rails.root.join('db', 'post_migrate', '20170502101023_cleanup_namespaceless_pending_delete_projects.rb')
+
+describe CleanupNamespacelessPendingDeleteProjects do
+  before do
+    # Stub after_save callbacks that will fail when Project has no namespace
+    allow_any_instance_of(Project).to receive(:ensure_dir_exist).and_return(nil)
+    allow_any_instance_of(Project).to receive(:update_project_statistics).and_return(nil)
+  end
+
+  describe '#up' do
+    it 'only cleans up pending delete projects' do
+      admin = create(:admin)
+      create(:empty_project)
+      create(:empty_project, pending_delete: true)
+      project = build(:empty_project, pending_delete: true, namespace_id: nil)
+      project.save(validate: false)
+
+      expect(NamespacelessProjectDestroyWorker).to receive(:bulk_perform_async).with([[project.id.to_s, admin.id, {}]])
+
+      described_class.new.up
+    end
+  end
+end
diff --git a/spec/workers/namespaceless_project_destroy_worker_spec.rb b/spec/workers/namespaceless_project_destroy_worker_spec.rb
new file mode 100644
index 00000000000..ed78236ebc0
--- /dev/null
+++ b/spec/workers/namespaceless_project_destroy_worker_spec.rb
@@ -0,0 +1,81 @@
+require 'spec_helper'
+
+describe NamespacelessProjectDestroyWorker do
+  subject { described_class.new }
+
+  before do
+    # Stub after_save callbacks that will fail when Project has no namespace
+    allow_any_instance_of(Project).to receive(:ensure_dir_exist).and_return(nil)
+    allow_any_instance_of(Project).to receive(:update_project_statistics).and_return(nil)
+  end
+
+  describe '#perform' do
+    context 'project has namespace' do
+      it 'does not do anything' do
+        project = create(:empty_project)
+
+        subject.perform(project.id, project.owner.id, {})
+
+        expect(Project.unscoped.all).to include(project)
+      end
+    end
+
+    context 'project has no namespace' do
+      let(:admin) { create(:admin) }
+
+      let!(:project) do
+        project = build(:empty_project, namespace_id: nil)
+        project.save(validate: false)
+        project
+      end
+
+      context 'project not a fork of another project' do
+        it "truncates the project's team" do
+          expect_any_instance_of(ProjectTeam).to receive(:truncate)
+
+          subject.perform(project.id, admin.id, {})
+        end
+
+        it 'deletes the project' do
+          subject.perform(project.id, admin.id, {})
+
+          expect(Project.unscoped.all).not_to include(project)
+        end
+
+        it 'does not call unlink_fork' do
+          is_expected.not_to receive(:unlink_fork)
+
+          subject.perform(project.id, admin.id, {})
+        end
+
+        it 'does not do anything in Project#remove_pages method' do
+          expect(Gitlab::PagesTransfer).not_to receive(:new)
+
+          subject.perform(project.id, admin.id, {})
+        end
+      end
+
+      context 'project forked from another' do
+        let!(:parent_project) { create(:empty_project) }
+
+        before do
+          create(:forked_project_link, forked_to_project: project, forked_from_project: parent_project)
+        end
+
+        it 'closes open merge requests' do
+          merge_request = create(:merge_request, source_project: project, target_project: parent_project)
+
+          subject.perform(project.id, admin.id, {})
+
+          expect(merge_request.reload).to be_closed
+        end
+
+        it 'destroys the link' do
+          subject.perform(project.id, admin.id, {})
+
+          expect(parent_project.forked_project_links).to be_empty
+        end
+      end
+    end
+  end
+end