Fix QRCodesController spec and add spec for UUID validation

app/models/profile.rb

@@ -22,13 +22,15 @@
 #  index_profiles_on_uuid         (uuid) UNIQUE
 #
 class Profile < ApplicationRecord
+  UUID_REGEX = /[0-9a-fA-F]{8}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{4}\b-[0-9a-fA-F]{12}/
+
   belongs_to :profileable, polymorphic: true
 
   has_one :self_ref, class_name: "Profile", foreign_key: :id, inverse_of: :self_ref, dependent: :destroy
   has_one :user, through: :self_ref, source: :profileable, source_type: "User"
   has_one :speaker, through: :self_ref, source: :profileable, source_type: "Speaker"
 
-  validates :uuid, uniqueness: true, presence: true
+  validates :uuid, uniqueness: true, presence: true, format: {with: UUID_REGEX}
 
   before_validation :set_uuid
 

spec/controllers/profiles_controller_spec.rb

@@ -24,12 +24,4 @@
       end
     end
   end
-
-  describe "GET #qr_code" do
-    it "returns a PNG" do
-      get :qr_code, params: {uuid: profile.uuid}
-      expect(response.headers["Content-Type"]).to eq("image/png")
-      expect(response.headers["Content-Disposition"]).to include("#{profile.name}.png")
-    end
-  end
 end

spec/controllers/qr_codes_controller_spec.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+RSpec.describe QRCodesController, type: :controller do
+  let(:profile) { create(:profile, :with_user, :public) }
+
+  before do
+    sign_in(profile.user)
+  end
+
+  describe "GET #show" do
+    it "returns a PNG" do
+      get :show, params: {profile_uuid: profile.uuid}
+      expect(response.headers["Content-Type"]).to eq("image/png")
+      expect(response.headers["Content-Disposition"]).to include("#{profile.name}.png")
+    end
+  end
+end

spec/models/profile_spec.rb

@@ -38,4 +38,20 @@
       expect(profile.uuid).to be_present
     end
   end
+
+  describe "validations" do
+    context "with a valid UUID" do
+      it "is valid" do
+        profile.uuid = SecureRandom.uuid
+        expect(profile).to be_valid
+      end
+    end
+
+    context "with an invalid UUID" do
+      it "is invalid" do
+        profile.uuid = "invalid"
+        expect(profile).not_to be_valid
+      end
+    end
+  end
 end