From bbaa216f9605e9474c3ec702c2a284bd0d055381 Mon Sep 17 00:00:00 2001
From: Chris Zetter <253059100+zetter-rpf@users.noreply.github.com>
Date: Thu, 26 Mar 2026 15:42:19 +0000
Subject: [PATCH] Return a 404 if a Scratch project doesn't exist

Fixes https://github.com/RaspberryPiFoundation/digital-editor-issues/issues/1269

Previously a 500 was raised if a scratch project wasn't found or we tried to load a project that was of another type. This is because these project don't have the expected ScratchComponents.

Instead use the Rails Finders for loading, which will raise as expected if a record isn't found. I think this simplifies this code and removes the misleading locale lookup - Scratch API requests don't provide a locale so it's confusing to make them look like they do.
---
 app/controllers/api/scratch/projects_controller.rb |  8 +-------
 app/controllers/api/scratch/scratch_controller.rb  |  3 +--
 .../scratch/showing_a_scratch_project_spec.rb      | 14 ++++++++++++++
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/app/controllers/api/scratch/projects_controller.rb b/app/controllers/api/scratch/projects_controller.rb
index 772056ee1..4d90722ff 100644
--- a/app/controllers/api/scratch/projects_controller.rb
+++ b/app/controllers/api/scratch/projects_controller.rb
@@ -62,13 +62,7 @@ def create_params
       end
 
       def load_original_project(identifier)
-        project_loader = ProjectLoader.new(identifier, [params[:locale]])
-        original_project = project_loader.load
-
-        raise ActiveRecord::RecordNotFound, I18n.t('errors.project.not_found') unless original_project
-        raise ActiveRecord::RecordNotFound, I18n.t('errors.project.not_found') unless original_project.scratch_project?
-
-        original_project
+        Project.find_by!(identifier:, project_type: Project::Types::CODE_EDITOR_SCRATCH)
       end
 
       def scratch_content_params
diff --git a/app/controllers/api/scratch/scratch_controller.rb b/app/controllers/api/scratch/scratch_controller.rb
index c1b792141..9b1d1b187 100644
--- a/app/controllers/api/scratch/scratch_controller.rb
+++ b/app/controllers/api/scratch/scratch_controller.rb
@@ -18,8 +18,7 @@ def check_scratch_feature
       end
 
       def load_project
-        project_loader = ProjectLoader.new(params[:id], [params[:locale]])
-        @project = project_loader.load
+        @project = Project.find_by!(identifier: params[:id], project_type: Project::Types::CODE_EDITOR_SCRATCH)
       end
     end
   end
diff --git a/spec/features/scratch/showing_a_scratch_project_spec.rb b/spec/features/scratch/showing_a_scratch_project_spec.rb
index 40bd25c3b..dcd760ca6 100644
--- a/spec/features/scratch/showing_a_scratch_project_spec.rb
+++ b/spec/features/scratch/showing_a_scratch_project_spec.rb
@@ -18,4 +18,18 @@
     data = JSON.parse(response.body, symbolize_names: true)
     expect(data).to have_key(:targets)
   end
+
+  it 'returns a 404 if project does not exist' do
+    get '/api/scratch/projects/non_existent_project'
+
+    expect(response).to have_http_status(:not_found)
+  end
+
+  it 'returns a 404 if project is not a scratch project' do
+    project = create(:project, project_type: Project::Types::PYTHON, locale: 'en')
+
+    get "/api/scratch/projects/#{project.identifier}"
+
+    expect(response).to have_http_status(:not_found)
+  end
 end