FIX: Use CDN URLs for topic thumbnails

app/models/topic.rb

@@ -84,6 +84,8 @@ class Topic < ActiveRecord::Base
       Jobs.enqueue(:generate_topic_thumbnails, { topic_id: id, extra_sizes: extra_sizes })
     end
 
+    infos.each { |i| i[:url] = UrlHelper.cook_url(i[:url], secure: original.secure?) }
+
     infos.sort_by! { |i| -i[:width] * i[:height] }
   end
 
@@ -102,7 +104,9 @@ class Topic < ActiveRecord::Base
       record.max_width == Topic.share_thumbnail_size[0] &&
         record.max_height == Topic.share_thumbnail_size[1]
     end
-    thumbnail&.optimized_image&.url || image_upload&.url
+
+    raw_url = thumbnail&.optimized_image&.url || image_upload&.url
+    UrlHelper.cook_url(raw_url, secure: image_upload&.secure?)
   end
 
   def featured_users

spec/components/topic_view_spec.rb

@@ -726,9 +726,9 @@ describe TopicView do
       end
 
       it "uses the topic image as a fallback when posts have no image" do
-        expect(topic_view_for_post(1).image_url).to eq(op_upload.url)
-        expect(topic_view_for_post(2).image_url).to eq(op_upload.url)
-        expect(topic_view_for_post(3).image_url).to eq(post3_upload.url)
+        expect(topic_view_for_post(1).image_url).to end_with(op_upload.url)
+        expect(topic_view_for_post(2).image_url).to end_with(op_upload.url)
+        expect(topic_view_for_post(3).image_url).to end_with(post3_upload.url)
       end
     end
 
@@ -736,7 +736,7 @@ describe TopicView do
       it "returns nil when posts have no image" do
         expect(topic_view_for_post(1).image_url).to eq(nil)
         expect(topic_view_for_post(2).image_url).to eq(nil)
-        expect(topic_view_for_post(3).image_url).to eq(post3_upload.url)
+        expect(topic_view_for_post(3).image_url).to end_with(post3_upload.url)
       end
     end
   end

spec/integration/topic_thumbnail_spec.rb

@@ -31,7 +31,7 @@ describe "Topic Thumbnails" do
       expect(thumbnails[0]["max_height"]).to eq(nil)
       expect(thumbnails[0]["width"]).to eq(image.width)
       expect(thumbnails[0]["height"]).to eq(image.height)
-      expect(thumbnails[0]["url"]).to eq(image.url)
+      expect(thumbnails[0]["url"]).to end_with(image.url)
 
       # Run the job
       args = Jobs::GenerateTopicThumbnails.jobs.last["args"].first

spec/serializers/topic_view_serializer_spec.rb

@@ -54,7 +54,7 @@ describe TopicViewSerializer do
       it 'should return the image url' do
         json = serialize_topic(topic, user)
 
-        expect(json[:image_url]).to eq(image_upload.url)
+        expect(json[:image_url]).to end_with(image_upload.url)
       end
 
       it 'should have thumbnails' do