与json.loads的Python3奇怪错误[重复]

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Let JSON object accept bytes or let urlopen output strings 11 answers
让JSON对象接受字节或让urlopen输出字符串11回答

I'm using flask in a web application that uses service api generates JSON response. The following part of the function works fine and returns JSON text output:

我在使用服务api的Web应用程序中使用flask生成JSON响应。该函数的以下部分工作正常并返回JSON文本输出：

def get_weather(query = 'london'):
    api_url = "http://api.openweathermap.org/data/2.5/weather?q={}&units=metric&appid=XXXXX****2a6eaf86760c"
    query = urllib.request.quote(query)
    url = api_url.format(query)
    response = urllib.request.urlopen(url)
    data = response.read()    
    return data

The output returned is:

返回的输出是：

{"coord":{"lon":-0.13,"lat":51.51},"weather":[{"id":803,"main":"Clouds","description":"broken clouds","icon":"04d"}],"base":"cmc stations","main":{"temp":12.95,"pressure":1030,"humidity":68,"temp_min":12.95,"temp_max":12.95,"sea_level":1039.93,"grnd_level":1030},"wind":{"speed":5.11,"deg":279.006},"clouds":{"all":76},"dt":1462290955,"sys":{"message":0.0048,"country":"GB","sunrise":1462249610,"sunset":1462303729},"id":2643743,"name":"London","cod":200}

This mean that data is a string, does not it?

这意味着数据是一个字符串，不是吗？

However, commenting the return data and then adding the following two lines:

但是，注释返回数据然后添加以下两行：

jsonData = json.loads(data)
return jsonData

generates the following error:

生成以下错误：

TypeError: the JSON object must be str, not 'bytes'

TypeError：JSON对象必须是str，而不是'bytes'

What's wrong? data, the JSON object, previously returned as a string! I need to know where is the mistake?

怎么了？数据，JSON对象，以前作为字符串返回！我需要知道错误在哪里？

1 个解决方案

#1

The data returned by request library is a binary string while json.loads accepts strings so you need to convert the data (decode) to a string using the encoding that your request returns (which is usually ok to assume that it is UTF-8).

请求库返回的数据是二进制字符串，而json.loads接受字符串，因此您需要使用请求返回的编码将数据（解码）转换为字符串（通常可以认为它是UTF-8）。

You should be able to just change your code to this:

您应该只需将代码更改为：

return json.loads(data.decode("utf-8"))

PS: Storing the variable right before returning it is redundant so I simplified things

PS：在返回变量之前存储变量是多余的，所以我简化了一些事情

#1