Pages within the eCommerce system can be augmented with CMExternalPage content objects. The commerce root object offers a field externalPage which allows to query the CMS page content given a page ID and a site ID. The following example query retrieves the header and main placements from the CMExternalPage associated with the about-us page:

{
  commerce {
    externalPage(externalId: "about-us",
                 siteId: "sfra-en-gb") {
      externalId
      name
      grid {
        placements(names: ["header", "main"]) {
          name
          items {
            name
            type
          }
        }
      }
    }
  }
}