Javascript API调用上的Node.js循环

我正在尝试使用不同的参数来获取一些API调用。获取数据并按天、城市最高温度、城市最低温度和有雨城市将其转换为CSV文件

API示例：

我有以下带有cities和api密钥的对象：

const cities = {
    0: ['Jerusalem', 'il'],
    1: ['New York', 'us'],
    2: ['Dubai', 'ae'],
    3: ['Lisbon', 'pt'],
    4: ['Oslo', 'no'],
    5: ['Paris', 'fr'],
    6: ['Berlin', 'de'],
    7: ['Athens', 'gr'],
    8: ['Seoul', 'kr'],
    9: ['Singapore', 'sgp'],
}

const apiKey = "[retracted]";

这是我要动态迭代的API调用，目前我只在第一个对象参数上运行它，并最终将信息推送到天气，以便我可以操作数据，按天（前5天）排序，然后显示温度最高的城市、温度最低的城市和所有有雨的城市：

request(`http://api.openweathermap.org/data/2.5/forecast?q=${cities[1][0]},${cities[1][1]}&mode=json&appid=${apiKey}`, (error, response, body) => {
    let data = JSON.parse(body);    
    let weather = {
        0: [day, highTemp, lowTemp, rain],
        1: [day, highTemp, lowTemp, rain],
        2: [day, highTemp, lowTemp, rain],
        3: [day, highTemp, lowTemp, rain],
        4: [day, highTemp, lowTemp, rain],
    }
    // day 1
    console.log(data['city']['name']);
    console.log(data['list'][0].dt_txt);
    console.log(data['list'][0].main['temp']);

    // day 2
    console.log(data['city']['name']);
    console.log(data['list'][8].dt_txt);
    console.log(data['list'][8].main['temp']);
    // day 3
    console.log(data['city']['name']);
    console.log(data['list'][16].dt_txt);
    console.log(data['list'][16].main['temp']);
    // day 4
    console.log(data['city']['name']);
    console.log(data['list'][24].dt_txt);
    console.log(data['list'][24].main['temp']);
    // day 5
    console.log(data['city']['name']);
    console.log(data['list'][32].dt_txt);
    console.log(data['list'][32].main['temp']);

});

我曾尝试使用带有key in对象的for循环，但不幸的是，它没有显示数据，错误原因未定义。

您可以使用它来实现这一点

当所有 作为可替代品通过的承诺已解决或当可替代品 没有承诺

您可以使用来实现这一点

当所有 作为可替代品通过的承诺已解决或当可替代品 没有承诺

---

我建议使用response promise native来允许使用async/await。这将允许我们遍历城市列表，并将每个城市的天气数据附加到城市详细信息（名称和国家）

一旦我们有了这些数据，我们就可以进行你提到的处理，我们可以得到最高和最低温度（注意，温度以开尔文为单位，所以我们将转换为摄氏度）

请务必指出，我是按本地日期分组的，如果您希望按utc日期分组，则应更改行：

let timeOffset = entry.dt + result.weatherResponse.city.timezone;

到

这是一种稍微不同的解释数据的方式

我现在已更新到group by date，结果如下所示：

按本地日期分组：

Date,Highest Temperature,Lowest Temperature,Cities With Rain
2019-11-01,Dubai,Oslo,"Paris,Berlin"
2019-11-02,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-03,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens,Singapore"
2019-11-04,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens"
2019-11-05,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-06,Singapore,Oslo,"Paris,Berlin,Singapore"
2019-11-07,Seoul,Seoul,""

按UTC日期分组：

Date,Highest Temperature,Lowest Temperature,Cities With Rain
2019-11-01,Dubai,Oslo,"Paris,Berlin"
2019-11-02,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-03,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens,Singapore"
2019-11-04,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens"
2019-11-05,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-06,Singapore,Oslo,"Paris,Berlin,Singapore"

守则：

const rp = require("request-promise-native");

const cities = {
    0: ['Jerusalem', 'il'],
    1: ['New York', 'us'],
    2: ['Dubai', 'ae'],
    3: ['Lisbon', 'pt'],
    4: ['Oslo', 'no'],
    5: ['Paris', 'fr'],
    6: ['Berlin', 'de'],
    7: ['Athens', 'gr'],
    8: ['Seoul', 'kr'],
    9: ['Singapore', 'sgp'],
}


async function getWeatherForCities() {
    let results = [];
    for (let [city, countryCode] of Object.values(cities)) {
        console.log(`Getting weather for city: ${city}, country: ${countryCode}...`);
        let weatherResponse = await rp({ url: `http://api.openweathermap.org/data/2.5/forecast?q=${city},${countryCode}&mode=json&appid=${apiKey}`, json: true});
        results.push ({ city, countryCode, list: weatherResponse.list, weatherResponse });
    }

    let summary = results.map(res => {  
        return { city: res.city, countryCode: res.countryCode,
        maxTemperature: getMaxTemperatureCelsius(res.list),
        minTemperature: getMinTemperatureCelsius(res.list),
        totalRainfall: getTotalRainFall(res.list)
    }});

    console.log("Summary (over forecasting interval): ", summary);
    console.log("Result with the highest temperature: ", [...summary].sort((resA, resB) => resB.maxTemperature - resA.maxTemperature)[0]);
    console.log("Result with the lowest temperature: ", [...summary].sort((resA, resB) => resA.minTemperature - resB.minTemperature)[0]);
    console.log("Cities with rain: ", summary.filter(res => res.totalRainfall).map(res => res.city));

    // Group by date (local) and city
    let resultsGroupedByDateAndCity = {};
    results.forEach(result => {
        result.list.forEach(entry => {
            let timeOffset = entry.dt + result.weatherResponse.city.timezone;
            let date = new Date(timeOffset * 1000);
            date.setHours(0,0,0,0);
            let dateKey = date.toISOString().substring(0,10);
            if (!resultsGroupedByDateAndCity[dateKey]) resultsGroupedByDateAndCity[dateKey] = {};
            if (!resultsGroupedByDateAndCity[dateKey][result.city]) resultsGroupedByDateAndCity[dateKey][result.city] = [];
            resultsGroupedByDateAndCity[dateKey][result.city].push(entry);
        });
    });

    // Run through the keys.
    let csvLines = ["Date,Highest Temperature,Lowest Temperature,Cities With Rain"];

    for (let [date, obj] of Object.entries(resultsGroupedByDateAndCity)) {
        let dailySummary = Object.entries(obj).map(([city, dayList]) => {  
            return { city,
            maxTemperature: getMaxTemperatureCelsius(dayList),
            minTemperature: getMinTemperatureCelsius(dayList),
            totalRainfall: getTotalRainFall(dayList)
        }});

        console.log("Details for date " + date + ": ");
        let resultWithHighestTemperature = [...dailySummary].sort((resA, resB) => resB.maxTemperature - resA.maxTemperature)[0];
        let resultWithLowestTemperature = [...dailySummary].sort((resA, resB) => resA.minTemperature - resB.minTemperature)[0];
        let citiesWithRain = dailySummary.filter(res => res.totalRainfall).map(res => res.city);
        console.log("Result with the highest temperature: ", resultWithHighestTemperature);
        console.log("Result with the lowest temperature: ", resultWithLowestTemperature);
        console.log("Cities with rain: ", citiesWithRain);

        csvLines.push([date, resultWithHighestTemperature.city, resultWithLowestTemperature.city, '"' + citiesWithRain.join(",") + '"'].join(","));
    }

    console.log("CSV result:\n", csvLines.join("\n"));
}

function KelvinToCelsius(kelvin) {
    return (kelvin - 273.15);
}

// Return the max temperature for the forecast
function getMaxTemperatureCelsius(responseList) {
    // Get a list of the max temperatures for the forecast.
    const maxTemps = responseList.map(entry => Number(entry.main.temp_max));
    return KelvinToCelsius(Math.max(...maxTemps));
}

// Return the min temperature for the forecast
function getMinTemperatureCelsius(responseList) {
    // Get a list of the min temperatures for the forecast.
    const minTemps = responseList.map(entry => Number(entry.main.temp_min));
    return KelvinToCelsius(Math.min(...minTemps));
}

// Return the total rainfall for the forecast
function getTotalRainFall(responseList) {
    // Get a list of the min temperatures for the forecast.
    const rain = responseList.map(entry => { return entry.rain ? Number(entry.rain["3h"]): 0 });
    return rain.reduce((sum, val) => sum + val, 0)
}

getWeatherForCities();

---

我建议使用response promise native来允许使用async/await。这将允许我们遍历城市列表，并将每个城市的天气数据附加到城市详细信息（名称和国家）

一旦我们有了这些数据，我们就可以进行你提到的处理，我们可以得到最高和最低温度（注意，温度以开尔文为单位，所以我们将转换为摄氏度）

请务必指出，我是按本地日期分组的，如果您希望按utc日期分组，则应更改行：

let timeOffset = entry.dt + result.weatherResponse.city.timezone;

到

这是一种稍微不同的解释数据的方式

我现在已更新到group by date，结果如下所示：

按本地日期分组：

Date,Highest Temperature,Lowest Temperature,Cities With Rain
2019-11-01,Dubai,Oslo,"Paris,Berlin"
2019-11-02,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-03,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens,Singapore"
2019-11-04,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens"
2019-11-05,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-06,Singapore,Oslo,"Paris,Berlin,Singapore"
2019-11-07,Seoul,Seoul,""

按UTC日期分组：

Date,Highest Temperature,Lowest Temperature,Cities With Rain
2019-11-01,Dubai,Oslo,"Paris,Berlin"
2019-11-02,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-03,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens,Singapore"
2019-11-04,Singapore,Oslo,"Lisbon,Paris,Berlin,Athens"
2019-11-05,Singapore,Oslo,"Lisbon,Paris,Berlin,Singapore"
2019-11-06,Singapore,Oslo,"Paris,Berlin,Singapore"

守则：

const rp = require("request-promise-native");

const cities = {
    0: ['Jerusalem', 'il'],
    1: ['New York', 'us'],
    2: ['Dubai', 'ae'],
    3: ['Lisbon', 'pt'],
    4: ['Oslo', 'no'],
    5: ['Paris', 'fr'],
    6: ['Berlin', 'de'],
    7: ['Athens', 'gr'],
    8: ['Seoul', 'kr'],
    9: ['Singapore', 'sgp'],
}


async function getWeatherForCities() {
    let results = [];
    for (let [city, countryCode] of Object.values(cities)) {
        console.log(`Getting weather for city: ${city}, country: ${countryCode}...`);
        let weatherResponse = await rp({ url: `http://api.openweathermap.org/data/2.5/forecast?q=${city},${countryCode}&mode=json&appid=${apiKey}`, json: true});
        results.push ({ city, countryCode, list: weatherResponse.list, weatherResponse });
    }

    let summary = results.map(res => {  
        return { city: res.city, countryCode: res.countryCode,
        maxTemperature: getMaxTemperatureCelsius(res.list),
        minTemperature: getMinTemperatureCelsius(res.list),
        totalRainfall: getTotalRainFall(res.list)
    }});

    console.log("Summary (over forecasting interval): ", summary);
    console.log("Result with the highest temperature: ", [...summary].sort((resA, resB) => resB.maxTemperature - resA.maxTemperature)[0]);
    console.log("Result with the lowest temperature: ", [...summary].sort((resA, resB) => resA.minTemperature - resB.minTemperature)[0]);
    console.log("Cities with rain: ", summary.filter(res => res.totalRainfall).map(res => res.city));

    // Group by date (local) and city
    let resultsGroupedByDateAndCity = {};
    results.forEach(result => {
        result.list.forEach(entry => {
            let timeOffset = entry.dt + result.weatherResponse.city.timezone;
            let date = new Date(timeOffset * 1000);
            date.setHours(0,0,0,0);
            let dateKey = date.toISOString().substring(0,10);
            if (!resultsGroupedByDateAndCity[dateKey]) resultsGroupedByDateAndCity[dateKey] = {};
            if (!resultsGroupedByDateAndCity[dateKey][result.city]) resultsGroupedByDateAndCity[dateKey][result.city] = [];
            resultsGroupedByDateAndCity[dateKey][result.city].push(entry);
        });
    });

    // Run through the keys.
    let csvLines = ["Date,Highest Temperature,Lowest Temperature,Cities With Rain"];

    for (let [date, obj] of Object.entries(resultsGroupedByDateAndCity)) {
        let dailySummary = Object.entries(obj).map(([city, dayList]) => {  
            return { city,
            maxTemperature: getMaxTemperatureCelsius(dayList),
            minTemperature: getMinTemperatureCelsius(dayList),
            totalRainfall: getTotalRainFall(dayList)
        }});

        console.log("Details for date " + date + ": ");
        let resultWithHighestTemperature = [...dailySummary].sort((resA, resB) => resB.maxTemperature - resA.maxTemperature)[0];
        let resultWithLowestTemperature = [...dailySummary].sort((resA, resB) => resA.minTemperature - resB.minTemperature)[0];
        let citiesWithRain = dailySummary.filter(res => res.totalRainfall).map(res => res.city);
        console.log("Result with the highest temperature: ", resultWithHighestTemperature);
        console.log("Result with the lowest temperature: ", resultWithLowestTemperature);
        console.log("Cities with rain: ", citiesWithRain);

        csvLines.push([date, resultWithHighestTemperature.city, resultWithLowestTemperature.city, '"' + citiesWithRain.join(",") + '"'].join(","));
    }

    console.log("CSV result:\n", csvLines.join("\n"));
}

function KelvinToCelsius(kelvin) {
    return (kelvin - 273.15);
}

// Return the max temperature for the forecast
function getMaxTemperatureCelsius(responseList) {
    // Get a list of the max temperatures for the forecast.
    const maxTemps = responseList.map(entry => Number(entry.main.temp_max));
    return KelvinToCelsius(Math.max(...maxTemps));
}

// Return the min temperature for the forecast
function getMinTemperatureCelsius(responseList) {
    // Get a list of the min temperatures for the forecast.
    const minTemps = responseList.map(entry => Number(entry.main.temp_min));
    return KelvinToCelsius(Math.min(...minTemps));
}

// Return the total rainfall for the forecast
function getTotalRainFall(responseList) {
    // Get a list of the min temperatures for the forecast.
    const rain = responseList.map(entry => { return entry.rain ? Number(entry.rain["3h"]): 0 });
    return rain.reduce((sum, val) => sum + val, 0)
}

getWeatherForCities();

---

---

您是在响应中获取数据还是在主体中获取数据？在主体中，我解析数据并将其保存到数据中。logs工作得很好，我只想使用从object cities获得的不同参数在API上进行循环。我想我们需要使用Promise，但我对它不太熟悉，这给我带来了很多麻烦。您是在响应中获取数据还是在body中获取数据？在body中，我解析它并将其保存到数据中。logs工作得很好，我只想使用从object cities获得的不同参数在API上进行循环。我想我们需要使用Promise，但我对它不太熟悉，这给我带来了很多麻烦。如果我在Promise中调用API，那么在get data中获取（URL）的目的是什么？好吗？@YonatanDarmon我忽略了这一点，谢谢。在

getData

中编辑了多余的promise调用。您正在

城市

和

fetch

中循环，逐个提取数据，然后

promise。all

将所有数据作为单个promise返回。但是fetch URL不是动态的，只能得到一个响应。我需要动态地这样做，如果我在阵列中更改城市，它将能够继续进行新的更改。我在问题的顶部添加了一个API示例，如果我在Promise中调用API，那么在get data中获取（URL）的目的是什么。好吗？@YonatanDarmon我忽略了这一点，谢谢。在

getData

中编辑了多余的promise调用。您正在

城市

和

fetch

中循环，逐个提取数据，然后

promise。all

将所有数据作为单个promise返回。但是fetch URL不是动态的，只能得到一个响应。我需要动态地这样做，如果我在阵列中更改城市，它将能够继续进行新的更改。我在我的问题上添加了一个API示例。这个答案为我提供了迄今为止最好的解决方案，顺便说一句，我添加了一些函数来获取每个城市的最高和最低温度，我将添加一些功能，以最高温度、最低温度对城市进行排序。等每个响应将为我们提供40个数据点，每天最多8个。这通常意味着我们将获得6天的数据（2部分+4完成），例如5,8,8,8,3。我认为为一天分配天气最可靠的方法是使用dt unix时间戳，并使用矩.js，或许可以从中获取一天（矩.utc（dt））（我猜他们使用的是utc时间！）如果我们只跳过每8个数据点，我们就有可能为天气分配错误的一天。啊，是的，我知道你在做什么，您将在5天内间隔1天拍摄快照。那就行了！我的逻辑是从每个位置的40个读数中获得最大值（每个参数）。我明白你的意思，这是一个很好的逻辑，但我尝试了更简单的方法。如果您在发布的答案上更改了，请告诉我，同时我将尝试计算如何显示五个不同的日期，并在每一天之间进行比较。这样我就可以将最终结果显示到CSV文件中。这个答案给了我迄今为止最好的解决方案，我如何操作它顺便说一句。我添加了一些函数来获取每个城市的最高和最低温度，我将添加一些功能，以按最高温度、最低温度对城市进行排序。等每个响应将为我们提供40个数据点，每天最多8个。这通常意味着我们将获得6天的数据（2部分+4补偿