Support adding and removing attributes of error templates

app/assets/javascripts/error_templates.js

@@ -0,0 +1,18 @@
+$(function() {
+    if ($.isController('error_templates')) {
+        $('#add-attribute').find('button').on('click', function () {
+            $.ajax(location + '/attribute.json', {
+                method: 'POST',
+                data: {
+                    _method: 'PUT',
+                    dataType: 'json',
+                    error_template_attribute_id: $('#add-attribute').find('select').val()
+                }
+            }).success(function () {
+                location.reload();
+            }).error(function (error) {
+                $.flash.danger({text: error.statusText});
+            });
+        });
+    }
+});

app/assets/stylesheets/error_templates.scss

@@ -0,0 +1,9 @@
+#add-attribute {
+  display: flex;
+  max-width: 400px;
+  margin-top: 30px;
+
+  button {
+    margin-left: 10px;
+  }
+}

app/controllers/error_templates_controller.rb

@@ -1,5 +1,5 @@
 class ErrorTemplatesController < ApplicationController
-  before_action :set_error_template, only: [:show, :edit, :update, :destroy]
+  before_action :set_error_template, only: [:show, :edit, :update, :destroy, :add_attribute, :remove_attribute]
 
   def authorize!
     authorize(@error_templates || @error_template)
@@ -73,6 +73,24 @@ class ErrorTemplatesController < ApplicationController
     end
   end
 
+  def add_attribute
+    authorize!
+    @error_template.error_template_attributes << ErrorTemplateAttribute.find(params['error_template_attribute_id'])
+    respond_to do |format|
+      format.html { redirect_to @error_template }
+      format.json { head :no_content }
+    end
+  end
+
+  def remove_attribute
+    authorize!
+    @error_template.error_template_attributes.delete(ErrorTemplateAttribute.find(params['error_template_attribute_id']))
+    respond_to do |format|
+      format.html { redirect_to @error_template }
+      format.json { head :no_content }
+    end
+  end
+
   private
     # Use callbacks to share common setup or constraints between actions.
     def set_error_template

app/policies/error_template_policy.rb

@@ -1,3 +1,9 @@
 class ErrorTemplatePolicy < AdminOnlyPolicy
+  def add_attribute?
+    admin?
+  end
 
+  def remove_attribute?
+    admin?
+  end
 end

app/views/error_templates/show.html.slim

@@ -31,4 +31,10 @@ h3
           td = attribute.description
           td = attribute.regex
           td = link_to(t('shared.show'), attribute)
-          td = "Remove"
+          td = link_to(t('shared.destroy'), attribute_error_template_url(:error_template_attribute_id => attribute.id), :method => :delete)
+
+#add-attribute
+  = collection_select({}, :error_template_attribute_id,
+          ErrorTemplateAttribute.where.not(id: @error_template.error_template_attributes.select(:id).to_a).order(:important, :key),
+          :id, :key, {include_blank: false}, class: '')
+  button.btn.btn-default = t('error_templates.add_attribute')