Add map download file size to travel advice download link

Author: GDSNewt

app/models/travel_advice.rb

@@ -20,6 +20,10 @@ def map_download_url
     content_store_response["details"].dig("document", "url")
   end
 
+  def map_download_file_size
+    content_store_response["details"].dig("document", "file_size")
+  end
+
   def email_signup_link
     content_store_response["details"]["email_signup_link"]
   end

app/views/travel_advice/_first_part.html.erb

@@ -14,8 +14,15 @@
     <img src="<%= content_item.map["url"] %>" alt="<%= content_item.map["alt_text"] %>" class="map-image">
     <% if content_item.map_download_url %>
       <figcaption>
+        <%
+          download_text = "Download a more detailed map (PDF"
+          if content_item.map_download_file_size
+            download_text += ", #{number_to_human_size(content_item.map_download_file_size)}"
+          end
+          download_text += ")"
+        %>
         <%= render "components/download_link", {
-          text: "Download a more detailed map (PDF)",
+          text: download_text,
           href: content_item.map_download_url,
         } %>
       </figcaption>

spec/models/travel_advice_spec.rb

@@ -24,4 +24,32 @@
       expect(alert_statuses).to be_empty
     end
   end
+
+  describe "#map_download_file_size" do
+    it "returns the file size when present" do
+      content_store_response["details"]["document"] = {
+        "url" => "https://example.com/map.pdf",
+        "file_size" => 201_672,
+      }
+
+      travel_advice = described_class.new(content_store_response)
+      expect(travel_advice.map_download_file_size).to eq(201_672)
+    end
+
+    it "returns nil when file size is not present" do
+      content_store_response["details"]["document"] = {
+        "url" => "https://example.com/map.pdf",
+      }
+
+      travel_advice = described_class.new(content_store_response)
+      expect(travel_advice.map_download_file_size).to be_nil
+    end
+
+    it "returns nil when document is not present" do
+      content_store_response["details"].delete("document")
+
+      travel_advice = described_class.new(content_store_response)
+      expect(travel_advice.map_download_file_size).to be_nil
+    end
+  end
 end