Scratch projects create action for remixing

app/controllers/api/scratch/projects_controller.rb

@@ -6,13 +6,27 @@ class ProjectsController < ScratchController
       skip_before_action :authorize_user, only: [:show]
       skip_before_action :check_scratch_feature, only: [:show]
 
+      before_action :ensure_create_is_a_remix, only: %i[create]
+
       def show
         render :show, formats: [:json]
       end
 
+      def create
+        render json: { status: 'ok', 'content-name': 'new-project-id' }, status: :ok
+      end
+
       def update
         render json: { status: 'ok' }, status: :ok
       end
+
+      private
+
+      def ensure_create_is_a_remix
+        return if params[:is_remix] == '1'
+
+        render json: { error: 'Only remixing existing projects is allowed' }, status: :forbidden
+      end
     end
   end
 end

config/routes.rb

@@ -34,7 +34,7 @@
 
   namespace :api do
     namespace :scratch do
-      resources :projects, only: %i[show update]
+      resources :projects, only: %i[show update create]
       get '/assets/internalapi/asset/:id(.:format)/get/' => 'assets#show'
       post '/assets/:id' => 'assets#create'
     end

spec/features/scratch/creating_a_scratch_project_spec.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe 'Creating a Scratch project (remixing)', type: :request do
+  let(:school) { create(:school) }
+  let(:teacher) { create(:teacher, school:) }
+  let(:cookie_headers) { { 'Cookie' => "scratch_auth=#{UserProfileMock::TOKEN}" } }
+  let(:params) { { original_id: 'original-project-id', project: { targets: [] }, is_remix: '1' } }
+
+  before do
+    Flipper.disable :cat_mode
+    Flipper.disable_actor :cat_mode, school
+  end
+
+  it 'responds 401 Unauthorized when no cookie is provided' do
+    post '/api/scratch/projects', params: params
+
+    expect(response).to have_http_status(:unauthorized)
+  end
+
+  it 'responds 404 Not Found when cat_mode is not enabled' do
+    authenticated_in_hydra_as(teacher)
+
+    post '/api/scratch/projects', params: params, headers: cookie_headers
+
+    expect(response).to have_http_status(:not_found)
+  end
+
+  it 'responds 403 Forbidden when not remixing' do
+    authenticated_in_hydra_as(teacher)
+    Flipper.enable_actor :cat_mode, school
+
+    post '/api/scratch/projects', params: params.merge(is_remix: '0'), headers: cookie_headers
+
+    expect(response).to have_http_status(:forbidden)
+  end
+
+  it 'return new project id when cat_mode is enabled and a cookie is provided' do
+    authenticated_in_hydra_as(teacher)
+    Flipper.enable_actor :cat_mode, school
+
+    post '/api/scratch/projects', params: params, headers: cookie_headers
+
+    expect(response).to have_http_status(:ok)
+
+    data = JSON.parse(response.body, symbolize_names: true)
+    expect(data[:status]).to eq('ok')
+    expect(data[:'content-name']).to eq('new-project-id')
+  end
+end