"@context":
  "@vocab": https://schema.org/
  merchant: https://developers.google.com/merchant/api/reference/rest/
  name: schema:name
  description: schema:description
  url: schema:url
  offerId: merchant:offerId
  channel: merchant:channel
  contentLanguage: merchant:contentLanguage
  feedLabel: merchant:feedLabel
  title: schema:name
  price: schema:price
  availability: schema:availability
  condition: schema:itemCondition
  brand: schema:brand
  gtin: schema:gtin
  storeCode: merchant:storeCode
  promotionId: merchant:promotionId
  targetCountry: merchant:targetCountry
  imageLink: schema:image