From b3a76289cc88b9f5426a6453751076eb8c9d4823 Mon Sep 17 00:00:00 2001
From: Shivam Mishra <scm.mymail@gmail.com>
Date: Thu, 29 May 2025 17:01:38 +0530
Subject: [PATCH] feat: use tracking pixel for article view count (#11559)

---
 .../api/v1/portals/articles_controller.rb     |  18 +++++++-
 app/views/layouts/portal.html.erb             |  24 +++++++++++
 config/routes.rb                              |   1 +
 public/assets/images/tracking-pixel.png       | Bin 0 -> 123 bytes
 .../v1/portals/articles_controller_spec.rb    |  40 +++++++++++++++++-
 5 files changed, 80 insertions(+), 3 deletions(-)
 create mode 100644 public/assets/images/tracking-pixel.png

diff --git a/app/controllers/public/api/v1/portals/articles_controller.rb b/app/controllers/public/api/v1/portals/articles_controller.rb
index d07dbcb9d..32a147d34 100644
--- a/app/controllers/public/api/v1/portals/articles_controller.rb
+++ b/app/controllers/public/api/v1/portals/articles_controller.rb
@@ -1,7 +1,7 @@
 class Public::Api::V1::Portals::ArticlesController < Public::Api::V1::Portals::BaseController
   before_action :ensure_custom_domain_request, only: [:show, :index]
   before_action :portal
-  before_action :set_category, except: [:index, :show]
+  before_action :set_category, except: [:index, :show, :tracking_pixel]
   before_action :set_article, only: [:show]
   layout 'portal'
 
@@ -15,6 +15,21 @@ class Public::Api::V1::Portals::ArticlesController < Public::Api::V1::Portals::B
 
   def show; end
 
+  def tracking_pixel
+    @article = @portal.articles.find_by(slug: permitted_params[:article_slug])
+    return head :not_found unless @article
+
+    @article.increment_view_count if @article.published?
+
+    # Serve the 1x1 tracking pixel with 24-hour private cache
+    # Private cache bypasses CDN but allows browser caching to prevent duplicate views from same user
+    expires_in 24.hours, public: false
+    response.headers['Content-Type'] = 'image/png'
+
+    pixel_path = Rails.public_path.join('assets/images/tracking-pixel.png')
+    send_file pixel_path, type: 'image/png', disposition: 'inline'
+  end
+
   private
 
   def limit_results
@@ -39,7 +54,6 @@ class Public::Api::V1::Portals::ArticlesController < Public::Api::V1::Portals::B
 
   def set_article
     @article = @portal.articles.find_by(slug: permitted_params[:article_slug])
-    @article.increment_view_count if @article.published?
     @parsed_content = render_article_content(@article.content)
   end
 
diff --git a/app/views/layouts/portal.html.erb b/app/views/layouts/portal.html.erb
index c4135fd37..6ed0c8201 100644
--- a/app/views/layouts/portal.html.erb
+++ b/app/views/layouts/portal.html.erb
@@ -73,6 +73,30 @@ By default, it renders:
         <% end %>
       </main>
     </div>
+    <% if @article.present? %>
+    <script>
+      (function() {
+        let viewTracked = false;
+        const trackView = function() {
+          if (!viewTracked) {
+            viewTracked = true;
+            const img = new Image();
+            img.src = '<%= request.base_url %>/hc/<%= @portal.slug %>/articles/<%= @article.slug %>.png';
+          }
+        };
+        
+        const addTrackingListeners = function() {
+          const events = ['mouseenter', 'touchstart', 'focus'];
+          events.forEach(event => {
+            document.body.addEventListener(event, function() {
+              setTimeout(trackView, 5000);
+            }, { once: true });
+          });
+        };
+        addTrackingListeners();
+      })();
+    </script>
+    <% end %>
   </body>
   <style>
   html.dark {
diff --git a/config/routes.rb b/config/routes.rb
index 9841c7103..ea65a02c9 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -449,6 +449,7 @@ Rails.application.routes.draw do
   get 'hc/:slug/:locale/categories', to: 'public/api/v1/portals/categories#index'
   get 'hc/:slug/:locale/categories/:category_slug', to: 'public/api/v1/portals/categories#show'
   get 'hc/:slug/:locale/categories/:category_slug/articles', to: 'public/api/v1/portals/articles#index'
+  get 'hc/:slug/articles/:article_slug.png', to: 'public/api/v1/portals/articles#tracking_pixel'
   get 'hc/:slug/articles/:article_slug', to: 'public/api/v1/portals/articles#show'
 
   # ----------------------------------------------------------------------
diff --git a/public/assets/images/tracking-pixel.png b/public/assets/images/tracking-pixel.png
new file mode 100644
index 0000000000000000000000000000000000000000..04cc712f24b2ecf0100a4c9b415783d8f8fba087
GIT binary patch
literal 123
zcmeAS@N?(olHy`uVBq!ia0vp^j3CUx1|;Q0k8}bl&H|6fVg?3oVGw3ym^DWNq@p;;
z-HBn{IhmJ04okYDuOkD)#(wTUiL5}rfTxRNNChJ!E5on<KrRrlGBBo8Otk<pJzf1=
J);T3K0Ra5c7l{A>

literal 0
HcmV?d00001

diff --git a/spec/controllers/public/api/v1/portals/articles_controller_spec.rb b/spec/controllers/public/api/v1/portals/articles_controller_spec.rb
index 08c5206c1..e6429a1de 100644
--- a/spec/controllers/public/api/v1/portals/articles_controller_spec.rb
+++ b/spec/controllers/public/api/v1/portals/articles_controller_spec.rb
@@ -82,7 +82,7 @@ RSpec.describe 'Public Articles API', type: :request do
       get "/hc/#{portal.slug}/articles/#{article.slug}"
       expect(response).to have_http_status(:success)
       expect(response.body).to include(ChatwootMarkdownRenderer.new(article.content).render_article)
-      expect(article.reload.views).to eq 1
+      expect(article.reload.views).to eq 0 # View count should not increment on show
     end
 
     it 'does not increment the view count if the article is not published' do
@@ -98,4 +98,42 @@ RSpec.describe 'Public Articles API', type: :request do
       expect(response).to have_http_status(:success)
     end
   end
+
+  describe 'GET /public/api/v1/portals/:slug/articles/:slug.png (tracking pixel)' do
+    it 'serves a PNG image and increments view count for published article' do
+      get "/hc/#{portal.slug}/articles/#{article.slug}.png"
+
+      expect(response).to have_http_status(:success)
+      expect(response.headers['Content-Type']).to eq('image/png')
+      expect(response.headers['Cache-Control']).to include('max-age=86400')
+      expect(response.headers['Cache-Control']).to include('private')
+      expect(article.reload.views).to eq 1
+    end
+
+    it 'serves a PNG image but does not increment view count for draft article' do
+      draft_article = create(:article, category: category, status: :draft, portal: portal, account_id: account.id, author_id: agent.id, views: 0)
+
+      get "/hc/#{portal.slug}/articles/#{draft_article.slug}.png"
+
+      expect(response).to have_http_status(:success)
+      expect(response.headers['Content-Type']).to eq('image/png')
+      expect(response.headers['Cache-Control']).to include('max-age=86400')
+      expect(response.headers['Cache-Control']).to include('private')
+      expect(draft_article.reload.views).to eq 0
+    end
+
+    it 'returns 404 if article does not exist' do
+      get "/hc/#{portal.slug}/articles/non-existent-article.png"
+
+      expect(response).to have_http_status(:not_found)
+    end
+
+    it 'sets proper cache headers for performance' do
+      get "/hc/#{portal.slug}/articles/#{article.slug}.png"
+
+      expect(response.headers['Cache-Control']).to include('max-age=86400')
+      expect(response.headers['Cache-Control']).to include('private')
+      expect(response.headers['Content-Type']).to eq('image/png')
+    end
+  end
 end