Merge pull request #385 from alphagov/govspeak-details-indexes

Add GA4 indexes to attachments that render a details component

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+* Add GA4 indexes to attachments that render a details component ([#385](https://github.com/alphagov/govspeak/pull/385))
+
 ## 10.0.1
 
 * Update dependencies

lib/govspeak/post_processor.rb

@@ -57,6 +57,11 @@ def self.extension(title, &block)
     end
 
     extension("embed attachment HTML") do |document|
+      # Attachments with details components need indexes set for GA4 tracking purposes
+      details_attachments = govspeak_document.attachments.select { |attachment| attachment[:alternative_format_contact_email] }
+      details_attachments_size = details_attachments.size
+      details_attachment_index = 0
+
       document.css("govspeak-embed-attachment").map do |el|
         attachment = govspeak_document.attachments.detect { |a| a[:id] == el["id"] }
 
@@ -65,11 +70,17 @@ def self.extension(title, &block)
           next
         end
 
+        if attachment[:alternative_format_contact_email]
+          details_attachment_index += 1
+          details_ga4_attributes = { index_section: details_attachment_index, index_section_count: details_attachments_size }
+        end
+
         attachment_html = GovukPublishingComponents.render(
           "govuk_publishing_components/components/attachment",
           attachment:,
           margin_bottom: 6,
           locale: govspeak_document.locale,
+          details_ga4_attributes:,
         )
         el.swap(attachment_html)
       end

test/govspeak_attachment_test.rb

@@ -52,4 +52,32 @@ def render_govspeak(govspeak, attachments = [])
     assert html_has_selector?(rendered, "section.gem-c-attachment")
     assert_match(/<p>some more text<\/p>/, rendered)
   end
+
+  test "renders attachments with details elements with the correct GA4 index" do
+    attachments = []
+
+    (1..3).each do |index|
+      attachments << {
+        id: "attachment#{index}.ods",
+        url: "http://example.com/attachment#{index}",
+        title: "Attachment Title #{index}",
+        alternative_format_contact_email: "example@gov.uk",
+      }
+    end
+
+    # Insert an attachment without a details element, to ensure our code to increment the index ignores these
+    attachments.insert(1, {
+      id: "attachment.pdf",
+      url: "http://example.com/attachment.pdf",
+      title: "Attachment Title",
+    })
+
+    rendered = render_govspeak("[Attachment:attachment1.ods]\n[Attachment:attachment.pdf]\n[Attachment:attachment2.ods]\n[Attachment:attachment3.ods]", attachments)
+    node = Nokogiri::HTML(rendered)
+    node.css(".gem-c-details").each_with_index.map do |details, index|
+      ga4_event = JSON.parse(details.attribute("data-ga4-event"))
+      assert_equal ga4_event["index_section"], index + 1
+      assert_equal ga4_event["index_section_count"], 3
+    end
+  end
 end