commerce/lib/saleor/queries/GetMenuBySlug.graphql

query GetMenuBySlug($slug: String!) {
  menu(slug: $slug, channel: "default-channel") {
    id
    slug
    name
    items {
      id
      name
      url
      collection {
        slug
      }
      children {
        id
        collection {
          slug
        }
      }
    }
  }
}