expireTime

The timestamp when this product becomes unavailable for SearchService.Search. Note that this is only applicable to Type.PRIMARY and Type.COLLECTION, and ignored for Type.VARIANT. In general, we suggest the users to delete the stale products explicitly, instead of using this field to determine staleness. If it is set, the Product is not available for SearchService.Search after expire_time. However, the product can still be retrieved by ProductService.GetProduct and ProductService.ListProducts. expire_time must be later than available_time and publish_time, otherwise an INVALID_ARGUMENT error is thrown. Corresponding properties: Google Merchant Center property expiration_date.