Merge branch 'feature/environment-teardown-when-branch-deleted' into 'master'

Stop environment when branch is deleted

## What does this MR do?

This MR adds a environment teardown service, that is called when user deletes a branch. This most often happens when merge requests is merged.

## Does this MR meet the acceptance criteria?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] API support added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing

## What are the relevant issue numbers?

Closes #23218

See merge request !7355

3 files changed, 161 insertions, 0 deletions

diff --git a/spec/services/after_branch_delete_service_spec.rb b/spec/services/after_branch_delete_service_spec.rb
new file mode 100644
index 00000000000..d29e0addb53
--- /dev/null
+++ b/spec/services/after_branch_delete_service_spec.rb
@@ -0,0 +1,15 @@
+require 'spec_helper'
+
+describe AfterBranchDeleteService, services: true do
+  let(:project) { create(:project) }
+  let(:user) { create(:user) }
+  let(:service) { described_class.new(project, user) }
+
+  describe '#execute' do
+    it 'stops environments attached to branch' do
+      expect(service).to receive(:stop_environments)
+
+      service.execute('feature')
+    end
+  end
+end
diff --git a/spec/services/ci/stop_environments_service_spec.rb b/spec/services/ci/stop_environments_service_spec.rb
new file mode 100644
index 00000000000..6f7d1a5d28d
--- /dev/null
+++ b/spec/services/ci/stop_environments_service_spec.rb
@@ -0,0 +1,105 @@
+require 'spec_helper'
+
+describe Ci::StopEnvironmentsService, services: true do
+  let(:project) { create(:project, :private) }
+  let(:user) { create(:user) }
+
+  let(:service) { described_class.new(project, user) }
+
+  describe '#execute' do
+    context 'when environment with review app exists' do
+      before do
+        create(:environment, :with_review_app, project: project,
+                                               ref: 'feature')
+      end
+
+      context 'when user has permission to stop environment' do
+        before do
+          project.team << [user, :developer]
+        end
+
+        context 'when environment is associated with removed branch' do
+          it 'stops environment' do
+            expect_environment_stopped_on('feature')
+          end
+        end
+
+        context 'when environment is associated with different branch' do
+          it 'does not stop environment' do
+            expect_environment_not_stopped_on('master')
+          end
+        end
+
+        context 'when specified branch does not exist' do
+          it 'does not stop environment' do
+            expect_environment_not_stopped_on('non/existent/branch')
+          end
+        end
+
+        context 'when no branch not specified' do
+          it 'does not stop environment' do
+            expect_environment_not_stopped_on(nil)
+          end
+        end
+
+        context 'when environment is not stoppable' do
+          before do
+            allow_any_instance_of(Environment)
+              .to receive(:stoppable?).and_return(false)
+          end
+
+          it 'does not stop environment' do
+            expect_environment_not_stopped_on('feature')
+          end
+        end
+      end
+
+      context 'when user does not have permission to stop environment' do
+        before do
+          project.team << [user, :guest]
+        end
+
+        it 'does not stop environment' do
+          expect_environment_not_stopped_on('master')
+        end
+      end
+    end
+
+    context 'when there is no environment associated with review app' do
+      before do
+        create(:environment, project: project)
+      end
+
+      context 'when user has permission to stop environments' do
+        before do
+          project.team << [user, :master]
+        end
+
+        it 'does not stop environment' do
+          expect_environment_not_stopped_on('master')
+        end
+      end
+    end
+
+    context 'when environment does not exist' do
+      it 'does not raise error' do
+        expect { service.execute('master') }
+          .not_to raise_error
+      end
+    end
+  end
+
+  def expect_environment_stopped_on(branch)
+    expect_any_instance_of(Environment)
+      .to receive(:stop!)
+
+    service.execute(branch)
+  end
+
+  def expect_environment_not_stopped_on(branch)
+    expect_any_instance_of(Environment)
+      .not_to receive(:stop!)
+
+    service.execute(branch)
+  end
+end
diff --git a/spec/services/delete_branch_service_spec.rb b/spec/services/delete_branch_service_spec.rb
new file mode 100644
index 00000000000..336f5dafb5b
--- /dev/null
+++ b/spec/services/delete_branch_service_spec.rb
@@ -0,0 +1,41 @@
+require 'spec_helper'
+
+describe DeleteBranchService, services: true do
+  let(:project) { create(:project) }
+  let(:repository) { project.repository }
+  let(:user) { create(:user) }
+  let(:service) { described_class.new(project, user) }
+
+  describe '#execute' do
+    context 'when user has access to push to repository' do
+      before do
+        project.team << [user, :developer]
+      end
+
+      it 'removes the branch' do
+        expect(branch_exists?('feature')).to be true
+
+        result = service.execute('feature')
+
+        expect(result[:status]).to eq :success
+        expect(branch_exists?('feature')).to be false
+      end
+    end
+
+    context 'when user does not have access to push to repository' do
+      it 'does not remove branch' do
+        expect(branch_exists?('feature')).to be true
+
+        result = service.execute('feature')
+
+        expect(result[:status]).to eq :error
+        expect(result[:message]).to eq 'You dont have push access to repo'
+        expect(branch_exists?('feature')).to be true
+      end
+    end
+  end
+
+  def branch_exists?(branch_name)
+    repository.ref_exists?("refs/heads/#{branch_name}")
+  end
+end