Added basic Registrant portal

app/models/registrant_user.rb

@@ -0,0 +1,46 @@
+require 'open3'
+
+# rubocop: disable Metrics/ClassLength
+class ApiUser < User
+  include EppErrors
+  def epp_code_map # rubocop:disable Metrics/MethodLength
+    {
+      '2306' => [ # Parameter policy error
+        [:password, :blank]
+      ]
+    }
+  end
+
+  # TODO: should have max request limit per day
+  belongs_to :registrar
+  has_many :certificates
+
+  validates :username, :password, :registrar, presence: true
+  validates :username, uniqueness: true
+
+  attr_accessor :registrar_typeahead
+
+  def ability
+    @ability ||= Ability.new(self)
+  end
+  delegate :can?, :cannot?, to: :ability
+
+  after_initialize :set_defaults
+  def set_defaults
+    return unless new_record?
+    self.active = true unless active_changed?
+  end
+
+  def registrar_typeahead
+    @registrar_typeahead || registrar || nil
+  end
+
+  def to_s
+    username
+  end
+
+  def queued_messages
+    registrar.messages.queued
+  end
+end
+# rubocop: enable Metrics/ClassLength