Display list of recipientgroups properly

- Use html5 validation
- initiate create action

app/controllers/admin/emails_controller.rb

 class Admin::EmailsController < Admin::ApplicationController
   def show
   end
+
+  def create
+    AdminEmailsWorker.perform_async(params[:recipients], params[:subject], params[:body])
+    redirect_to admin_email_path, notice: 'Email send'
+  end
+
+  protected
 end

app/helpers/admin_email_helper.rb

@@ -2,7 +2,7 @@ module AdminEmailHelper
   def admin_email_grouped_recipient_options
     options_for_select([['Everyone', 'all']]) +
     grouped_options_for_select(
-      'Groups' => Group.pluck(:name, :id).map{ |name, id| [name, "group_#{id}"] },
+      'Groups' => Group.pluck(:name, :id).map{ |name, id| [name, "group-#{id}"] },
       'Projects' => grouped_project_list
     )
   end
@@ -12,7 +12,7 @@ module AdminEmailHelper
     Group.includes(:projects).flat_map do |group|
       group.human_name
       group.projects.map do |project|
-        ["#{group.human_name} / #{project.name}", "project_#{project.id}"]
+        ["#{group.human_name} / #{project.name}", "project-#{project.id}"]
       end
     end
   end

app/views/admin/emails/show.html.haml

@@ -7,17 +7,16 @@
   .form-group
     %label.control-label{for: :subject} Subject
     .col-sm-10
-      = text_field_tag :subject, '', class: 'form-control'
+      = text_field_tag :subject, '', class: 'form-control', required: true
 
   .form-group
     %label.control-label{for: :body} Body
     .col-sm-10
-      = text_area_tag :body, '', class: 'form-control', rows: 15
+      = text_area_tag :body, '', class: 'form-control', rows: 15, required: true
 
   .form-group
-    %label.control-label{for: :recipients} Recipients
+    %label.control-label{for: :recipients} Recipient group
     .col-sm-10
-      = select_tag :recipients,  admin_email_grouped_recipient_options, class: :select2
-
+      = select_tag :recipients, admin_email_grouped_recipient_options, class: :select2, required: true
   .form-actions
     = submit_tag 'Send message', class: 'btn btn-create'

config/routes.rb

@@ -86,7 +86,7 @@ Gitlab::Application.routes.draw do
     resources :broadcast_messages, only: [:index, :create, :destroy]
     resource :logs, only: [:show]
     resource :background_jobs, controller: 'background_jobs', only: [:show]
-    resource :email, only: [:show]
+    resource :email, only: [:show, :create]
 
     resources :projects, constraints: { id: /[a-zA-Z.\/0-9_\-]+/ }, only: [:index, :show] do
       member do

spec/routing/admin_routing_spec.rb

@@ -123,4 +123,8 @@ describe Admin::EmailsController, "routing" do
   it "to #show" do
     get("/admin/email").should route_to('admin/emails#show')
   end
+
+  it "to #create" do
+    post("/admin/email").should route_to('admin/emails#create')
+  end
 end