framework: assets: version: SomeVersionScheme version_format: '%%s?version=%%s' base_urls: http://cdn.example.com packages: images_path: base_path: '/foo' images: version: 1.0.0 base_urls: ["http://images1.example.com", "http://images2.example.com"] foo: version: 1.0.0 version_format: '%%s-%%s' bar: base_urls: ["https://bar2.example.com"] bar_null_version: version: null base_urls: "https://bar3.example.com"