Add "simple" parameter to tournament show

app/controllers/tournaments_controller.rb

@@ -25,7 +25,11 @@ class TournamentsController < ApplicationController
 
   # GET /tournaments/1
   def show
-    render json: @tournament, include: '**'
+    if show_params.fetch(:simple, 'false') == 'true'
+      render json: @tournament, serializer: SimpleTournamentSerializer
+    else
+      render json: @tournament, include: '**'
+    end
   end
 
   # POST /tournaments
@@ -116,6 +120,10 @@ class TournamentsController < ApplicationController
     params.permit(:type)
   end
 
+  def show_params
+    params.permit(:simple)
+  end
+
   def tournament_params
     params.slice(:name, :description, :public, :teams, :group_stage, :playoff_teams_amount).permit!
   end

spec/controllers/tournaments_controller_spec.rb

@@ -102,6 +102,15 @@ RSpec.describe TournamentsController, type: :controller do
       get :show, params: { id: @tournament.to_param }
       expect(deserialize_response(response)[:id].to_i).to eq(@tournament.id)
     end
+
+    context 'with simple=true parameter' do
+      it 'returns no relations' do
+        get :show, params: { id: @tournament.to_param, simple: 'true' }
+        body = deserialize_response response
+        expect(body[:stages]).to be_nil
+        expect(body[:teams]).to be_nil
+      end
+    end
   end
 
   describe 'POST #create' do