Add expires_at columns to user model

lib/generators/shopify_app/user_model/templates/db/migrate/add_user_expires_at_column.erb

@@ -0,0 +1,5 @@
+class AddUserExpiresAtColumn < ActiveRecord::Migration[<%= rails_migration_version %>]
+  def change
+    add_column :users, :expires_at, :datetime
+  end
+end

lib/generators/shopify_app/user_model/user_model_generator.rb

@@ -40,6 +40,24 @@ def create_scopes_storage_in_user_model
         end
       end
 
+      def create_expires_at_storage_in_user_model
+        expires_at_column_prompt = <<~PROMPT
+          It is highly recommended that apps record the User session expiry date. \
+          This will allow apps to check if the session has expired and re-authenticate \
+          without a first call to Shopify.
+
+          The following migration will add an `expires_at` column to the User model. \
+          Do you want to include this migration? [y/n]
+        PROMPT
+
+        if new_shopify_cli_app? || Rails.env.test? || yes?(expires_at_column_prompt)
+          migration_template(
+            "db/migrate/add_user_expires_at_column.erb",
+            "db/migrate/add_user_expires_at_column.rb",
+          )
+        end
+      end
+
       def update_shopify_app_initializer
         gsub_file("config/initializers/shopify_app.rb", "ShopifyApp::InMemoryUserSessionStore", "User")
       end

test/generators/user_model_generator_test.rb

@@ -35,7 +35,14 @@ class UserModelGeneratorTest < Rails::Generators::TestCase
     end
   end
 
-  test "create User with access_scopes migration with --new-shopify-cli-app flag provided" do
+  test "create expires_at migration for User model" do
+    run_generator
+    assert_migration "db/migrate/add_user_expires_at_column.rb" do |migration|
+      assert_match "add_column :users, :expires_at, :datetime", migration
+    end
+  end
+
+  test "create User with all migrations with --new-shopify-cli-app flag provided" do
     Rails.env = "mock_environment"
 
     run_generator ["--new-shopify-cli-app"]
@@ -44,6 +51,9 @@ class UserModelGeneratorTest < Rails::Generators::TestCase
     assert_migration "db/migrate/add_user_access_scopes_column.rb" do |migration|
       assert_match "add_column :users, :access_scopes, :string", migration
     end
+    assert_migration "db/migrate/add_user_expires_at_column.rb" do |migration|
+      assert_match "add_column :users, :expires_at, :datetime", migration
+    end
   end
 
   test "updates the shopify_app initializer to use User to store session" do