Javascript 为API调用返回未定义的节点JS

我正在使用开放天气API，对于风速，它返回未定义，但其他两个（时间和温度）工作正常

var request = require('request');
var yargs = require('yargs');
var fs = require ('fs');
var forecasts = require('./forecast.json');
var args = yargs.argv;

var url = 'http://api.openweathermap.org/data/2.5/forecast?q=erie,pa&APPID=a0472e6063198c88952f86f836355ae1&units=imperial';

request({url: url, json: true},function(error,response,body){
var time = 0;
body.list.forEach(function(measurement){
    var forecast = {Wind_Speed: measurement.main.wind, time: time, temp: measurement.main.temp};

    forecasts.push(forecast);
    time = time + 3

    console.log(forecast)
})
fs.writeFile('forecast.json',JSON.stringify(forecasts))
})

---

我刚刚检查了API，看起来风不在主要物体下方，你应该直接从测量中获取：

var forecast = {
   Wind_Speed: measurement.wind.speed, 
   time: time, 
   temp: measurement.main.temp
};

格式化的API响应：