Validate format of identifier for public project

This uses the recently added `PublicProject` wrapper class to add the
validation just in the context of the `Api::PublicProjectsController`.

The validation is based on the regular expression in
`PhaseIdentifier::PATTERN`, i.e. kebab-case.

Author: floehopper

lib/concepts/public_project/operations/create.rb

@@ -6,12 +6,14 @@ class << self
       def call(project_hash:)
         response = OperationResponse.new
 
-        project = Project.new(project_hash).tap do |p|
-          p.skip_identifier_generation = true
-        end
-        project.save!
+        public_project = PublicProject.new(
+          Project.new(project_hash).tap do |p|
+            p.skip_identifier_generation = true
+          end
+        )
+        public_project.save!
 
-        response[:project] = project
+        response[:project] = public_project.project
         response
       rescue StandardError => e
         Sentry.capture_exception(e)

spec/concepts/public_project/create_spec.rb

@@ -55,5 +55,17 @@
         expect(create_project[:error]).to eq("Error creating project: Validation failed: Identifier can't be blank")
       end
     end
+
+    context 'when identifier is in invalid format' do
+      let(:identifier) { 'FooBarBaz' }
+
+      it 'returns failure' do
+        expect(create_project.failure?).to be(true)
+      end
+
+      it 'returns error message' do
+        expect(create_project[:error]).to eq('Error creating project: Validation failed: Identifier is invalid')
+      end
+    end
   end
 end