Resolve "Avatar URLs are wrong when using a CDN path and Object Storage"

app/models/concerns/avatarable.rb

@@ -31,12 +31,13 @@ module Avatarable
 
     asset_host = ActionController::Base.asset_host
     use_asset_host = asset_host.present?
+    use_authentication = respond_to?(:public?) && !public?
 
     # Avatars for private and internal groups and projects require authentication to be viewed,
     # which means they can only be served by Rails, on the regular GitLab host.
     # If an asset host is configured, we need to return the fully qualified URL
     # instead of only the avatar path, so that Rails doesn't prefix it with the asset host.
-    if use_asset_host && respond_to?(:public?) && !public?
+    if use_asset_host && use_authentication
       use_asset_host = false
       only_path = false
     end
@@ -49,6 +50,6 @@ module Avatarable
       url_base << gitlab_config.relative_url_root
     end
 
-    url_base + avatar.url
+    url_base + avatar.local_url
   end
 end

app/uploaders/gitlab_uploader.rb

@@ -65,6 +65,10 @@ class GitlabUploader < CarrierWave::Uploader::Base
     !!model
   end
 
+  def local_url
+    File.join('/', self.class.base_dir, dynamic_segment, filename)
+  end
+
   private
 
   # Designed to be overridden by child uploaders that have a dynamic path

changelogs/unreleased/44775-avatar-on-os-fails-with-cdn.yml

+---
+title: Fixed wrong avatar URL when the avatar is on object storage.
+merge_request: 18092
+author:
+type: fixed

spec/models/concerns/avatarable_spec.rb

 require 'spec_helper'
 
 describe Avatarable do
-  set(:project) { create(:project, avatar: fixture_file_upload(File.join(Rails.root, 'spec/fixtures/dk.png'))) }
+  let(:project) { create(:project, :with_avatar) }
 
   let(:gitlab_host) { "https://gitlab.example.com" }
   let(:relative_url_root) { "/gitlab" }
@@ -37,11 +37,23 @@ describe Avatarable do
         project.visibility_level = visibility_level
       end
 
-      let(:avatar_path) { (avatar_path_prefix + [project.avatar.url]).join }
+      let(:avatar_path) { (avatar_path_prefix + [project.avatar.local_url]).join }
 
       it 'returns the expected avatar path' do
         expect(project.avatar_path(only_path: only_path)).to eq(avatar_path)
       end
+
+      context "when avatar is stored remotely" do
+        before do
+          stub_uploads_object_storage(AvatarUploader)
+
+          project.avatar.migrate!(ObjectStorage::Store::REMOTE)
+        end
+
+        it 'returns the expected avatar path' do
+          expect(project.avatar_url(only_path: only_path)).to eq(avatar_path)
+        end
+      end
     end
   end
 end