coinbase prices google apps script

coinbase_price.gs

/**
 * Get the coinbase price.
 *
 * @param {string} currency_pair The currency pair (BTC-EUR, ETH-EUR or LTC-EUR)
 * @param {string} price_type The price type (buy, sell or spot
 * @return The current price on coinbase
 * @customfunction
 */
function COINBASE_PRICE(currency_pair, price_type) {
  //if (currency_pair == null) {
  //  currency_pair = "BTC-EUR"
  //}
  //if (price_type == null) {
  //  price_type = "spot"
  //}
  var valid_currency_pairs = [ "BTC-EUR", "ETH-EUR", "LTC-EUR" ]
  var valid_price_types = [ "buy", "sell", "spot" ]
  
  if (valid_currency_pairs.indexOf(currency_pair) == -1) {
    throw new Error('Invalid currency_pair: ' + currency_pair + " Valid pairs are: " + valid_currency_pairs.join(","))
  }
  if (valid_price_types.indexOf(price_type) == -1) {
    throw new Error('Invalid price_type: ' + price_type + " Valid types are: " + valid_price_types.join(","))
  }
  var url = "https://api.coinbase.com/v2/prices/" + currency_pair + "/" + price_type
  
  var response = UrlFetchApp.fetch(url)
  var data = JSON.parse(response)
  var price = data.data.amount
  
  return price
}