Python-requests之POST Data的json問題

代碼如下:

import json
import requests
r = requests.post(url, data = {"a": json.dumps({"b": "c"})}); #url為隨意URL

使用Fiddler抓包，雖然在WebForms里面看到格式如下:

但是在Raw中看到結果如下:

即自動執行了urlencode，查看requests/models.py源碼發現，如果數據可迭代，即自動加入"application/x-www-form-urlencoded"頭，並且執行urlencode:

PreparedRequest類的prepare_body方法中

if data:
    body = self._encode_params(data)
    if isinstance(data, basestring) or hasattr(data, 'read'):
        content_type = None
    else:
        content_type = 'application/x-www-form-urlencoded'

RequestEncodingMixin類中_encode_params(data)方法中

if isinstance(data, (str, bytes)):
    return data
elif hasattr(data, 'read'):
    return data
elif hasattr(data, '__iter__'):
    result = []
    for k, vs in to_key_val_list(data):
        if isinstance(vs, basestring) or not hasattr(vs, '__iter__'):
            vs = [vs]
        for v in vs:
            if v is not None:
                result.append(
                    (k.encode('utf-8') if isinstance(k, str) else k,
                     v.encode('utf-8') if isinstance(v, str) else v))
    return urlencode(result, doseq=True)
else:
    return data

解決辦法:

import json
import requests

headers = {"Content-Type": "application/x-www-form-urlencoded"} 
data = "a=%s" %  json.dumps({"b": "c"})
r = requests.post(url, data = data, headers = headers);