Get instances from Publishing API

In some circumstances (such as guides), instances can be over multiple pages, so we can’t reliably get the number of instances from the preview, so we need to get the metadata directly from the Publishing API
alphagov · Dec 9, 2024 · d49745c · d49745c
1 parent 2d074c8
commit d49745c
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Showing 2 changed files with 20 additions and 6 deletions.
diff --git a/lib/engines/content_block_manager/app/services/content_block_manager/get_preview_content.rb b/lib/engines/content_block_manager/app/services/content_block_manager/get_preview_content.rb
@@ -90,8 +90,13 @@ def content_block_spans(nokogiri_html)
       nokogiri_html.css("span[data-content-id=\"#{@content_block_edition.document.content_id}\"]")
     end
 
+    def metadata
+      response = Services.publishing_api.get_content_by_embedded_document(@content_block_edition.document.content_id, { host_content_id: @content_id })
+      response.parsed_content
+    end
+
     def instances_count
-      content_block_spans(html).length
+      metadata["results"][0]["instances"]
     end
 
     ERROR_HTML = "<html><body><p>Preview not found</p></body></html>".freeze

diff --git a/lib/engines/content_block_manager/test/unit/app/services/get_preview_content_test.rb b/lib/engines/content_block_manager/test/unit/app/services/get_preview_content_test.rb
@@ -32,6 +32,19 @@ class ContentBlockManager::GetPreviewContentTest < ActiveSupport::TestCase
   let(:block_to_preview) do
     build(:content_block_edition, :email_address, document:, details: { "email_address" => "[email protected]" }, id: 1)
   end
+  let(:metadata_response) do
+    stub(:response, parsed_content: {
+      "results" => [
+        { "instances" => 2 },
+      ],
+    })
+  end
+
+  before do
+    Services.publishing_api.expects(:get_content_by_embedded_document)
+            .with(block_to_preview.document.content_id, { host_content_id: })
+            .returns(metadata_response)
+  end
 
   describe "#for_content_id" do
     setup do
@@ -57,16 +70,12 @@ class ContentBlockManager::GetPreviewContentTest < ActiveSupport::TestCase
     it "returns the count of instances" do
       Net::HTTP.expects(:get).with(URI(Plek.website_root + host_base_path)).returns(fake_frontend_response)
 
-      expected_content = {
-        instances_count: 1,
-      }
-
       actual_content = ContentBlockManager::GetPreviewContent.for_content_id(
         content_id: host_content_id,
         content_block_edition: block_to_preview,
       )
 
-      assert_equal expected_content[:instances_count], actual_content.instances_count
+      assert_equal 2, actual_content.instances_count
     end
 
     it "returns the preview html" do