在Tkinter中调用OpenWeatherMap API无法获取温度的问题

我用OpenWeatherMap API获取城市温度时失败了，能正常拿到城市名称，但温度等数据取不到，应该是数据提取方式错了，但找不到问题在哪。

我的代码 #

def format_response(weather):
    try:
        name = weather['city']['name']
        temperature = weather['main']['temp']
        final_str = f'City: {name} \n Temperature {temperature}'
    except:
        final_str = 'There was a problem retrieving that information'

    return final_str

API响应示例（与控制台输出一致） #

{
  "cod": "200",
  "message": 0,
  "cnt": 40,
  "list": [
    {
      "dt": 1647345600,
      "main": {
        "temp": 286.88,
        "feels_like": 285.93,
        "temp_min": 286.74,
        "temp_max": 286.88,
        "pressure": 1021,
        "sea_level": 1021,
        "grnd_level": 1018,
        "humidity": 62,
        "temp_kf": 0.14
      },
      "weather": [
        {
          "id": 804,
          "main": "Clouds",
          "description": "overcast clouds",
          "icon": "04d"
        }
      ],
      "clouds": {
        "all": 85
      },
      "wind": {
        "speed": 3.25,
        "deg": 134,
        "gust": 4.45
      },
      "visibility": 10000,
      "pop": 0,
      "sys": {
        "pod": "d"
      },
      "dt_txt": "2022-03-15 12:00:00"
    },
    {
      "dt": 1647356400,
      "main": {
        "temp": 286.71,
        "feels_like": 285.77,
        "temp_min": 286.38,
        "temp_max": 286.71,
        "pressure": 1021,
        "sea_level": 1021,
        "grnd_level": 1017,
        "humidity": 63,
        "temp_kf": 0.33
      },
      "weather": [
        {
          "id": 804,
          "main": "Clouds",
          "description": "overcast clouds",
          "icon": "04d"
        }
      ],
      "clouds": {
        "all": 90
      },
      "wind": {
        "speed": 3.34,
        "deg": 172,
        "gust": 4.03
      },
      "visibility": 10000,
      "pop": 0,
      "sys": {
        "pod": "d"
      },
      "dt_txt": "2022-03-15 15:00:00"
    },

    ...

 ],
  "city": {
    "id": 2643743,
    "name": "London",
    "coord": {
      "lat": 51.5073,
      "lon": -0.1277
    },
    "country": "GB",
    "population": 1000000,
    "timezone": 0,
    "sunrise": 1647324903,
    "sunset": 1647367441
  }
}

解决方案 #

问题出在数据结构层级：你调用的是5天天气预报API，main字段不在响应顶层，而是嵌套在list数组的每个元素里。直接取weather['main']['temp']会因找不到字段报错。

如果要获取第一个时段的温度，修改代码如下：

def format_response(weather):
    try:
        name = weather['city']['name']
        # 从list数组第一个元素中提取温度
        temperature = weather['list'][0]['main']['temp']
        # 可选：将开尔文温度转为摄氏度
        temperature_c = round(temperature - 273.15, 2)
        final_str = f'城市: {name} \n 温度: {temperature_c}°C'
    except KeyError as e:
        final_str = f'获取信息出错: 缺少字段 {e}'
    except Exception as e:
        final_str = f'获取信息出错: {str(e)}'

    return final_str

补充说明 #

• list数组的每个元素对应不同时间点的天气数据，list[0]是返回结果中最早的时段数据
• OpenWeatherMap默认返回开尔文温度，转摄氏度需减去273.15
• 替换泛用except为具体异常捕获，便于定位问题

内容的提问来源于stack exchange，提问作者Josborne