最后一個axios-request回應的回應為空

我想獲取給定地點的當前天氣狀況。為了實作這一點，我使用了兩個API。第一個是Mapbox，我用它來將地名地理編碼為地理坐標，第二個是Accuweather API。我還使用了 Axios 模塊 來向 API發出HTTP 請求。

為了避免回呼地獄和多層代碼并使其更易于閱讀和維護，我制作了 3 個函式：

1. cityToCoordinates獲取地點/城市名稱的經緯度。
2. coordinatesToPlaceID使用Accuweather獲取坐標的地點ID
3. placeIDToCurrentForecast獲取該地點的當前天氣

由于 axios 請求使用Promises ，我將所有三個函式設為異步。

問題出在placeIDToCurrentForecast函式中，呼叫coordinatesToPlaceID后then函式中的回呼回應始終未定義，盡管請求已成功發出并且我列印了回應。

這是腳本：

const axios = require("axios").default || require("axios");

const cityToCoordinates = async (cityName) => {
    const geoCodeBaseURL = " https://api.mapbox.com/geocoding/v5/mapbox.places/";
    const mapbowAcessToken = "MAPBOX_TOKEN";
    const limit = 1;
    const cityNameUrlEncoded = encodeURIComponent(cityName);

    return await axios
        .get(
            `${geoCodeBaseURL}${cityNameUrlEncoded}.json?access_token=${mapbowAcessToken}&limit=${limit}`
        )
        .then((response) => {
            const responseObject = response.data;

            if (responseObject.features.length === 0) {
                console.log("Sorry no such place exists");
                return;
            } else {
                const location = responseObject.features["0"].center;
                const longitude = location[0];
                const latitude = location[1];

                return {
                    latitude: latitude,
                    longitude: longitude,
                };
            }
        })
        .catch((error) => {
            console.log("An error has occured in city to coordinates");
            // console.log(error);
        });
};

const coordinatesToPlaceID = async (cityName) => {
    const coordinatesToPlaceApiURL = "http://dataservice.accuweather.com/locations/v1/cities/geoposition/search";
    const accuWeatherApiKey = "ACCUWEATHER_API_KEY";

    await cityToCoordinates(cityName).then(async (response) => {
        const query = `${response.latitude},${response.longitude}`;
        const queryUrlEncoded = encodeURIComponent(query);

        return await axios
            .get(
                `${coordinatesToPlaceApiURL}?q=${queryUrlEncoded}&apikey=${accuWeatherApiKey}`
            )
            .then((response) => {
                console.log(response.data.Key);
                return response.data.Key;
            })
            .catch((error) => {
                console.log("An error has occured in coordinates to place ID");
                // console.log(error);
            });
    });
};

const placeIDToCurrentForecast = async (cityName) => {
    const placeIdToCurrentWeather = "http://dataservice.accuweather.com/currentconditions/v1/";
    const accuWeatherApiKey = "ACCUWEATHER_API_KEY";

    await coordinatesToPlaceID(cityName).then(async (response) => {
        console.log(response); // Always undefined!!!

        if (response) {
            const placeId = response;

            await axios
                .get(`${placeIdToCurrentWeather}${placeId}?apikey=${accuWeatherApiKey}`)
                .then((response) => {
                    console.log(
                        "The current weathr in "  
                        cityName  
                        " is "  
                        response.data[0].Temperature.Metric.Value  
                        "° C"
                    );
                })
                .catch((error) => {
                    console.log("An error has occured in place ID to current forecast");
                    // console.log(error);
                });
        } else {
            console.log("There is no response");
        }
    });
};

placeIDToCurrentForecast("California");

輸出 ：

332131
undefined
There is no response

為什么回應未定義，我該如何改進代碼？

uj5u.com熱心網友回復：

您正在函式中回傳undefined，coordinatesToPlaceID請檢查。此外，如果您正在使用then，則可以避免使用async-await，反之亦然

const coordinatesToPlaceID = (cityName) => {
    const coordinatesToPlaceApiURL = "http://dataservice.accuweather.com/locations/v1/cities/geoposition/search";
    const accuWeatherApiKey = "ACCUWEATHER_API_KEY";

    return cityToCoordinates(cityName).then((response) => {
        const query = `${response.latitude},${response.longitude}`;
        const queryUrlEncoded = encodeURIComponent(query);

        return axios
            .get(
                `${coordinatesToPlaceApiURL}?q=${queryUrlEncoded}&apikey=${accuWeatherApiKey}`
            )
            .then((response) => {
                console.log(response.data.Key);
                return response.data.Key;
            })
            .catch((error) => {
                console.log("An error has occured in coordinates to place ID");
                // console.log(error);
            });
    });
};

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