检查JSON属性是否存在

Question

I am importing stock JSON data from Yahoo Finance to import into Google Sheets for a personal stock tracker using a custom function:

function _yahoofinance(ticker) {
  const url = 'https://query2.finance.yahoo.com/v10/finance/quoteSummary/' + encodeURI(ticker)
            + '?modules=price,assetProfile,summaryDetail,incomeStatementHistory,'
            + 'balanceSheetHistory,defaultKeyStatistics,financialData,calendarEvents,'
            + 'recommendationTrend,upgradeDowngradeHistory,majorHoldersBreakdown'
  ;

  const response = UrlFetchApp.fetch(url, { muteHttpExceptions: true });
  const responseCode = response.getResponseCode();
  
  if (responseCode === 200) {
    const quote = JSON.parse(response.getContentText());

    const price       = _isEmpty(quote.quoteSummary.result[0].price.regularMarketPrice)     ? '-' : quote.quoteSummary.result[0].price.regularMarketPrice.fmt; 
    const divYield    = _isEmpty(quote.quoteSummary.result[0].summaryDetail.dividendYield)  ? '-' : quote.quoteSummary.result[0].summaryDetail.dividendYield.raw * 100;
    const payoutRatio = _isEmpty(quote.quoteSummary.result[0].summaryDetail.payoutRatio)    ? '-' : quote.quoteSummary.result[0].summaryDetail.payoutRatio.raw * 100;
    const marketCap   = _isEmpty(quote.quoteSummary.result[0].summaryDetail.marketCap)      ? '-' : quote.quoteSummary.result[0].summaryDetail.marketCap.fmt;
    const fwdPE       = _isEmpty(quote.quoteSummary.result[0].summaryDetail.forwardPE)      ? '-' : quote.quoteSummary.result[0].summaryDetail.forwardPE.fmt;
    const revenue     = _isEmpty(quote.quoteSummary.result[0].financialData.totalRevenue)   ? '-' : quote.quoteSummary.result[0].financialData.totalRevenue.fmt;
    const revGrowth   = _isEmpty(quote.quoteSummary.result[0].financialData.revenueGrowth)  ? '-' : quote.quoteSummary.result[0].financialData.revenueGrowth.raw * 100;
    const earnGrowth  = _isEmpty(quote.quoteSummary.result[0].financialData.earningsGrowth) ? '-' : quote.quoteSummary.result[0].financialData.earningsGrowth.raw * 100;
    const freeCash    = _isEmpty(quote.quoteSummary.result[0].financialData.freeCashflow)   ? '-' : quote.quoteSummary.result[0].financialData.freeCashflow.fmt;


      return [[divYield, payoutRatio, marketCap, fwdPE, revenue, revGrowth, earnGrowth, freeCash]];
  }
}

function _isEmpty(obj) {
    return Object.keys(obj).length === undefined;
}

Please see an example sheet

问题是：并非每个股票都将拥有我从Yahoo请求的所有财产。我尝试以许多不同的方式来处理这一点：

const payoutRatio = _isEmpty(quote.quoteSummary.result[0].summaryDetail.payoutRatio)

function _isEmpty(obj) {
    return Object.keys(obj).length === undefined;
}

但是这些都没有作用。在示例表中，我试图在Ticker 0p0001703k.sw 上删除数据，这是ETF，因此它将没有库存的所有属性。 Google表返回一个错误：

#Error! TypeError: Cannot read property 'totalRevenue' of undefined (line 19).

这使我一半发疯了：DI一直在尝试以多种方式捕获此类错误。我的问题是：检查属性是否存在的正确方法是什么？您的帮助将不胜感激！

[编辑]解决方案：

function _yahoofinance(ticker) {
  const url = 'https://query2.finance.yahoo.com/v10/finance/quoteSummary/' + encodeURI(ticker)
            + '?modules=price,assetProfile,summaryDetail,incomeStatementHistory,'
            + 'balanceSheetHistory,defaultKeyStatistics,financialData,calendarEvents,'
            + 'recommendationTrend,upgradeDowngradeHistory,majorHoldersBreakdown'
  ;

  const response = UrlFetchApp.fetch(url, { muteHttpExceptions: true });
  const responseCode = response.getResponseCode();
  
  if (responseCode === 200) {
    const quote = JSON.parse(response.getContentText());

    const price       = quote.quoteSummary.result[0]?.price?.regularMarketPrice?.fmt     || '-'; 
    const divYield    = quote.quoteSummary.result[0]?.summaryDetail?.dividendYield?.raw  ?  '-' : quote.quoteSummary.result[0].summaryDetail.dividendYield.raw * 100;
    const payoutRatio = quote.quoteSummary.result[0]?.summaryDetail?.payoutRatio?.raw    ?  '-' : quote.quoteSummary.result[0].summaryDetail.payoutRatio.raw * 100;
    const revenue     = quote.quoteSummary.result[0]?.financialData?.totalRevenue?.fmt   || '-';

    return [[price, divYield, payoutRatio, revenue]];
  }
}

Answer 1

您可以使用 _isempty（）函数，因为您检查 quote.quotesummary.result [0] .financialdata.totalrevenue 是空的>。这意味着 FinancialData 是未定义的，并且甚至在进入您的ISEMPTY函数之前就会引发错误。

在您的示例中，这将是：

const quote = {
  quoteSummary: {
    result: [{}]
  }
}
const revenue = quote.quoteSummary.result?.[0]?.financialData?.totalRevenue?.fmt || '-';
console.log(revenue);