Add 'publish' funcionality for popular links

app/controllers/homepage_controller.rb

@@ -23,6 +23,11 @@ def update
     render "homepage/popular_links/edit"
   end
 
+  def publish
+    publish_latest_popular_links
+    render "homepage/popular_links/show"
+  end
+
 private
 
   def fetch_latest_popular_link
@@ -42,4 +47,8 @@ def remove_leading_and_trailing_url_spaces(links)
     end
     link_items
   end
+
+  def publish_latest_popular_links
+    @latest_popular_links.publish_popular_links
+  end
 end

app/helpers/popular_links_helper.rb

@@ -15,6 +15,16 @@ def primary_button_for(model, url, text)
     end
   end
 
+  def secondary_button_for(model, url, text)
+    form_for model, url:, method: :post do
+      render "govuk_publishing_components/components/button", {
+        text:,
+        margin_bottom: 3,
+        secondary_solid: true,
+      }
+    end
+  end
+
   def primary_link_button_for(url, text)
     render "govuk_publishing_components/components/button", {
       text:,

app/models/action.rb

@@ -17,6 +17,7 @@ class Action
     PUBLISH                     = "publish".freeze,
     ARCHIVE                     = "archive".freeze,
     NEW_VERSION                 = "new_version".freeze,
+    PUBLISH_POPULAR_LINKS       = "publish_popular_links".freeze,
   ].freeze
 
   NON_STATUS_ACTIONS = [

app/models/workflow.rb

@@ -93,6 +93,10 @@ class CannotDeletePublishedPublication < RuntimeError; end
         transition all => :archived, :unless => :archived?
       end
 
+      event :publish_popular_links do
+        transition %i[draft] => :published
+      end
+
       state :in_review do
         validates :review_requested_at, presence: true
       end

app/views/homepage/popular_links/_sidebar.html.erb

@@ -8,5 +8,6 @@
     <%= primary_button_for(@latest_popular_links, create_popular_links_path, "Create new edition") %>
   <% else %>
     <%= primary_link_button_for(edit_popular_links_path(@latest_popular_links), "Edit popular links") %>
+    <%= secondary_button_for(@latest_popular_links, publish_popular_links_path(@latest_popular_links), "Publish") %>
   <% end %>
 </div>

config/routes.rb

@@ -76,6 +76,7 @@
   post "/homepage/popular-links/create" => "homepage#create", as: "create_popular_links"
   get "/homepage/popular-links/:id" => "homepage#edit", as: "edit_popular_links"
   patch "/homepage/popular-links/:id" => "homepage#update", as: "update_popular_links"
+  post "/homepage/popular-links/:id/publish" => "homepage#publish", as: "publish_popular_links"
 
   mount GovukAdminTemplate::Engine, at: "/style-guide"
   mount Flipflop::Engine => "/flipflop"

test/functional/homepage_controller_test.rb

@@ -98,4 +98,20 @@ class HomepageControllerTest < ActionController::TestCase
       assert_template "homepage/popular_links/edit"
     end
   end
+
+  context "#publish" do
+    setup do
+      @popular_links = FactoryBot.create(:popular_links, state: "draft")
+    end
+
+    should "publish latest draft popular links and render show template" do
+      assert_equal "draft", PopularLinksEdition.last.state
+
+      post :publish, params: { id: @popular_links.id }
+
+      assert_response :ok
+      assert_template "homepage/popular_links/show"
+      assert_equal "published", PopularLinksEdition.last.state
+    end
+  end
 end