aablinov · May 13, 2020 16:58 · May 13, 2020
diff --git a/service.rb b/service.rb
@@ -0,0 +1,57 @@
+# gem https://github.com/AaronLasseigne/active_interaction
+
+module Excursion
+  module Services
+    class NewUser < ActiveInteraction::Base
+      string :email
+
+      def execute
+        user = User.create(email: email)
+        if user.persisted?
+          user
+        else
+          errors.merge!(user.errors)
+        end
+      end
+    end
+  end
+end
+
+module Excursion
+  module Services
+    class JoinUser < ActiveInteraction::Base
+      object :record, class: Record
+      string :email
+      string :group
+
+      def execute
+        return unless can?
+
+        exists_user = User.find_by_email(email) # Or UserRepository.new.find(email) no matter
+        if exists_user
+          record.users << exists_user
+        else
+          user = NewUser.run!(email: email)
+          record.users << user
+        end
+      end
+
+      private
+
+      def can?
+        # some bussiness checks
+        errors.add('Business not valid')
+        false
+      end
+    end
+  end
+end
+
+# Before any form object you want to check email format etc. (grape/dry)
+# Or create custom email type in ActiveInteraction and change string :email with email :email ¯\_(ツ)_/¯
+params do
+  requires :email, regexp: /.+@.+/
+end
+
+service = Excursion::Services::JoinUser.run(record: Record.find, group: 'a', email: params[:email])
+service.valid? ? service.result : service.errors.full_messages
No results found