（节点：52585）UnhandledPromiseRejectionWarning：未处理的承诺拒绝

Question

我有一个函数，我使用导入的 npm 包 current-weather-data 根据位置的经度和纬度获取某个位置的天气。我以前从未使用过 Promise，因为我通常使用 await 和 async，但这似乎很有趣且值得学习……在下面运行这段代码时，它不会呈现页面并给我错误 (node:52585) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag - -unhandled-rejections=strict (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2) (node:52585) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

这是我的代码：

 app.get('/admin-dashboard', (req, res) => {
    if (req.session.loggedin) {

     
      
        const location = {
            lat: 43.955540,
            lon: -79.480950
        }
         
    

        getWeather(location)
            .then(weather => {
                console.log(`The temperature here is: ${weather.temperature.value}`)
               
         
          
        res.render("admin-dashboard", {
            page_title: "admin-dashboard",
            FN: req.session.firstname,
            LN: req.session.lastname,
            weather: ${weather.temperature.value},
          });
        }).catch(err => console.log(err));
    } else {
        res.render('login.ejs')
    }
})

Answer 1

您没有捕获getWeather 函数引发的错误。您可以在函数中添加.catch，例如

app.get('/admin-dashboard', (req, res) => {
    if (req.session.loggedin) {
      const location = {
            lat: 43.955540,
            lon: -79.480950
        }
      getWeather(location).then(weather => {
        console.log(`The temperature here is: ${weather.temperature.value}`);
        res.render('admin-dashboard', {
          page_title: "admin-dashboard",
          FN: req.session.firstname,
          LN: req.session.lastname,
          weather: weather.temperature.value,
        }).catch(err => console.log(err));
      })
    } else {
      res.render('login.ejs')
    }
})

或者如果你更舒服，你可以使用 async/await

try {
    const weather = await getWeather(location);
    console.log(`The temperature here is ${weather.temperature.value}`);

    res.render("admin-dashboard", {
        page_title: "admin-dashboard",
        FN: req.session.firstname,
        LN: req.session.lastname,
        weather: weather.temperature.value,
    });
} catch(err) {
    console.log(err);
}

请注意，我只是记录错误，您可以根据需要处理它们。