Support flat response for envs index route

To support environment folders in the UI on the Environments List
page, the environments index route previously returned one environment
per folder, excluding those other than the latest deploy. However, the
environtments dropdown on the metrics dashboard requires that any
environment be selectable.

To accommodate both use cases, support an optional 'nested' parameter
in the index route to return either a flat, complete response or a
nested response based on the use case in question. The new default
response structure is the flat response.

1 files changed, 36 insertions, 7 deletions

diff --git a/spec/controllers/projects/environments_controller_spec.rb b/spec/controllers/projects/environments_controller_spec.rb
index 94fb85f217c..a4d494a820f 100644
--- a/spec/controllers/projects/environments_controller_spec.rb
+++ b/spec/controllers/projects/environments_controller_spec.rb
@@ -47,9 +47,43 @@ describe Projects::EnvironmentsController do
 
       let(:environments) { json_response['environments'] }
 
+      context 'with default parameters' do
+        before do
+          get :index, params: environment_params(format: :json)
+        end
+
+        it 'responds with a flat payload describing available environments' do
+          expect(environments.count).to eq 3
+          expect(environments.first['name']).to eq 'production'
+          expect(environments.second['name']).to eq 'staging/review-1'
+          expect(environments.third['name']).to eq 'staging/review-2'
+          expect(json_response['available_count']).to eq 3
+          expect(json_response['stopped_count']).to eq 1
+        end
+
+        it 'sets the polling interval header' do
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(response.headers['Poll-Interval']).to eq("3000")
+        end
+      end
+
+      context 'when a folder-based nested structure is requested' do
+        before do
+          get :index, params: environment_params(format: :json, nested: true)
+        end
+
+        it 'responds with a payload containing the latest environment for each folder' do
+          expect(environments.count).to eq 2
+          expect(environments.first['name']).to eq 'production'
+          expect(environments.second['name']).to eq 'staging'
+          expect(environments.second['size']).to eq 2
+          expect(environments.second['latest']['name']).to eq 'staging/review-2'
+        end
+      end
+
       context 'when requesting available environments scope' do
         before do
-          get :index, params: environment_params(format: :json, scope: :available)
+          get :index, params: environment_params(format: :json, nested: true, scope: :available)
         end
 
         it 'responds with a payload describing available environments' do
@@ -64,16 +98,11 @@ describe Projects::EnvironmentsController do
           expect(json_response['available_count']).to eq 3
           expect(json_response['stopped_count']).to eq 1
         end
-
-        it 'sets the polling interval header' do
-          expect(response).to have_gitlab_http_status(:ok)
-          expect(response.headers['Poll-Interval']).to eq("3000")
-        end
       end
 
       context 'when requesting stopped environments scope' do
         before do
-          get :index, params: environment_params(format: :json, scope: :stopped)
+          get :index, params: environment_params(format: :json, nested: true, scope: :stopped)
         end
 
         it 'responds with a payload describing stopped environments' do