Pass registrar in URL instead of POST params

app/assets/javascripts/admin/autocomplete.js.coffee

@@ -47,12 +47,6 @@ class @Autocomplete
       selector: '.js-contact-typeahead'
       hiddenSelector: '.js-contact-id'
 
-  @bindAdminRegistrarSearch: ->
-    Autocomplete.bindTypeahead
-      remote: '/admin/registrars/search'
-      selector: '.js-registrar-typeahead'
-      hiddenSelector: '.js-registrar-id'
-
   @bindClientContactSearch: ->
     Autocomplete.bindTypeahead
       remote: '/client/contacts/search'

app/controllers/admin/api_users_controller.rb

@@ -2,6 +2,7 @@ module Admin
   class ApiUsersController < BaseController
     load_and_authorize_resource
     before_action :set_api_user, only: [:show, :edit, :update, :destroy]
+    before_action :find_registrar, only: %i[new create]
 
     def index
       @q = ApiUser.includes(:registrar).search(params[:q])
@@ -9,12 +10,11 @@ module Admin
     end
 
     def new
-      @registrar = Registrar.find_by(id: params[:registrar_id])
-      @api_user = ApiUser.new(registrar: @registrar)
+      @api_user = ApiUser.new
     end
 
     def create
-      @api_user = ApiUser.new(api_user_params)
+      @api_user = @registrar.api_users.build(api_user_params)
 
       if @api_user.save
         flash[:notice] = I18n.t('record_created')
@@ -63,8 +63,11 @@ module Admin
 
     def api_user_params
       params.require(:api_user).permit(:username, :plain_text_password, :active,
-                                       :registrar_id, :registrar_typeahead,
                                        :identity_code, { roles: [] })
     end
+
+    def find_registrar
+      @registrar = Registrar.find(params[:registrar_id])
+    end
   end
 end

app/models/api_user.rb

@@ -28,7 +28,6 @@ class ApiUser < User
   delegate :code, :name, to: :registrar, prefix: true
 
   alias_attribute :login, :username
-  attr_accessor :registrar_typeahead
 
   SUPER = 'super'
   EPP = 'epp'
@@ -53,10 +52,6 @@ class ApiUser < User
     end
   end
 
-  def registrar_typeahead
-    @registrar_typeahead || registrar || nil
-  end
-
   def to_s
     username
   end

app/views/admin/api_users/_form.haml

@@ -1,4 +1,4 @@
-= form_for([:admin, @api_user], html: {class: 'form-horizontal', autocomplete: 'off'}) do |f|
+= form_for([:admin, @registrar, @api_user], html: {class: 'form-horizontal', autocomplete: 'off'}) do |f|
   = render 'shared/full_errors', object: @api_user
 
   .row
@@ -20,18 +20,6 @@
         .col-md-7
           = f.text_field(:identity_code, class: 'form-control')
 
-      .form-group
-        .form-group.has-feedback.js-typeahead-container
-          .col-md-4.control-label
-            = f.label :registrar_typeahead, t(:registrar_name), class: 'required'
-          .col-md-7
-            = f.text_field(:registrar_typeahead,
-              class: 'form-control js-registrar-typeahead typeahead required',
-              placeholder: t(:registrar_name), autocomplete: 'off')
-            %span.glyphicon.glyphicon-ok.form-control-feedback.js-typeahead-ok.hidden
-            %span.glyphicon.glyphicon-remove.form-control-feedback.js-typeahead-remove
-            = f.hidden_field(:registrar_id, class: 'js-registrar-id')
-
       .form-group
         .col-md-4.control-label
           = f.label :role, nil, class: 'required'
@@ -49,8 +37,3 @@
   .row
     .col-md-8.text-right
       = button_tag(t(:save), class: 'btn btn-primary')
-
-:javascript
-  window.addEventListener('load', function() {
-    Autocomplete.bindAdminRegistrarSearch();
-  });

config/routes.rb

@@ -259,7 +259,7 @@ Rails.application.routes.draw do
     end
 
     resources :registrars do
-      resources :api_users, except: %i[create show edit update destroy]
+      resources :api_users, except: %i[show edit update destroy]
       resources :white_ips
     end
 
@@ -270,7 +270,7 @@ Rails.application.routes.draw do
     end
 
     resources :admin_users
-    resources :api_users, except: %i[new] do
+    resources :api_users, except: %i[new create] do
       resources :certificates do
         member do
           post 'sign'