Authorize access before serving project template

Previously, if a user was a guest member of a private project, they
could access the merge request template as we were not checking
permission-levels of the user.

When a issue template is asked for, the user must have :read_issue for
the project; or :read_merge_request when a merge request template is
asked for.

We also now rescue_from FileNotFoundError and handle as 404. This is
because RepoTemplateFinder can raise a FileNotFoundError exception,
which Rails previously handled as a 500.

Handling these in a way that is consistent with
ActiveRecord::RecordNotFound exceptions, within controllers that
inherit from Projects::ApplicationController at least, and returning a
404.

https://gitlab.com/gitlab-org/gitlab-ce/issues/54943

1 files changed, 20 insertions, 0 deletions

diff --git a/spec/routing/project_routing_spec.rb b/spec/routing/project_routing_spec.rb
index 83775b1040e..6dde40d1cb6 100644
--- a/spec/routing/project_routing_spec.rb
+++ b/spec/routing/project_routing_spec.rb
@@ -693,4 +693,24 @@ describe 'project routing' do
 
     it_behaves_like 'redirecting a legacy project path', "/gitlab/gitlabhq/settings/repository", "/gitlab/gitlabhq/-/settings/repository"
   end
+
+  describe Projects::TemplatesController, 'routing' do
+    describe '#show' do
+      def show_with_template_type(template_type)
+        "/gitlab/gitlabhq/templates/#{template_type}/template_name"
+      end
+
+      it 'routes when :template_type is `merge_request`' do
+        expect(get(show_with_template_type('merge_request'))).to route_to('projects/templates#show', namespace_id: 'gitlab', project_id: 'gitlabhq', template_type: 'merge_request', key: 'template_name', format: 'json')
+      end
+
+      it 'routes when :template_type is `issue`' do
+        expect(get(show_with_template_type('issue'))).to route_to('projects/templates#show', namespace_id: 'gitlab', project_id: 'gitlabhq', template_type: 'issue', key: 'template_name', format: 'json')
+      end
+
+      it 'routes to application#route_not_found when :template_type is unknown' do
+        expect(get(show_with_template_type('invalid'))).to route_to('application#route_not_found', unmatched_route: 'gitlab/gitlabhq/templates/invalid/template_name')
+      end
+    end
+  end
 end