python post请求，application/x-www-form-urlencoded格式，提交数据key、val均需URL转码

今天研究一个接口，post请求，application/x-www-form-urlencoded格式 --表单形式提交

1、application/x-www-form-urlencoded

1）浏览器的原生form表单
2） 提交的数据按照 key1=val1&key2=val2 的方式进行编码，key和val都进行了URL转码

POST [http://www.example.com](http://www.example.com) HTTP/1.1 
Content-Type: application/x-[www-form-urlencoded](http://www-form-urlencoded);charset=utf-8 

title=test&sub%5B%5D=1&sub%5B%5D=2&sub%5B%5D=3 

2. 接口相关内容：

fiddler抓包，

 

 

postman正常请求成功，fiddler抓包，参数如上所示；raw 中可看到，已 进行了 转码

python代码如下：

urlq = "http://xx.xx.xx.xxx:xxxx/ncmisservice/contract/creditContract/callbackYZ"
headers = {"Content-Type":"application/x-www-form-urlencoded"}
data = {
        "serno": "10000320042201578",
        "prdCode": "YGYZD",
        "contracts": [{
                "pdfFileId": "b4f1b909ba4711e982ec00163e0cdd78",
                "signDt": "2019-08-26 15:18:22",
                "contractName": "xxxx授信合同",
                "contNo": "30010320042201133",
                "contTyp": "01"
        }],
        "legalInfo": {
                "legalPhone": "15810145528",
                "openingBank": "招商银行",
                "cardNumber": "23423423647",
                "bankMobileNumber": "15810145528"
        }
}
data['serno'] = '10000320120338114'
data['contracts'][0]['contNo'] = '3'

#youzanShouxinContract = json.dumps(youzanShouxinContract)
redata = {
    "serviceId":'contractsInfo',
    "data": data
}
redata = json.dumps(redata) #dict 转成 json
print(type(redata),redata)
re = requests.post(url=urlq, headers=headers, data=redata)
但是发现不通。通过fiddler抓包，参数如下:
 

 

 代码一直不通，一直给错误提示，如下：

 一直在提示 必填字符data 不存在。无论是将data单独转成json 字符串，还是redata整体转成json 字符串，都不行。 

知识点：dict 字典转json字符串：redata = json.dumps(redata) 

后来，终于找到了一种可以的。 redata整体进行转义：redata = urlencode(redata)  ---关键点

代码如下：

from urllib.parse import urlencode

urlq = "http://xx.xx.xx.xxx:xxxx/ncmisservice/contract/creditContract/callbackYZ"
headers = {"Content-Type":"application/x-www-form-urlencoded"}
data = {
        "serno": "10000320042201578",
        "prdCode": "YGYZD",
        "contracts": [{
                "pdfFileId": "b4f1b909ba4711e982ec00163e0cdd78",
                "signDt": "2019-08-26 15:18:22",
                "contractName": "xxxx贷授信合同",
                "contNo": "30010320042201133",
                "contTyp": "01"
        }],
        "legalInfo": {
                "legalPhone": "15810145528",
                "openingBank": "招商银行",
                "cardNumber": "23423423647",
                "bankMobileNumber": "15810145528"
        }
}
data['serno'] = '10000320120338114'
data['contracts'][0]['contNo'] = '3'
redata = {
    "serviceId":'contractsInfo',
    "data": data
}
redata = urlencode(redata)     #key关键点
print(type(redata),redata)
re = requests.post(url=urlq, headers=headers, data=redata)
python代码再次运行，成功。

关键点：表单提交，即application/x-www-form-urlencoded 这种请求方式，
表单提交的数据，按照key1=val1&key2=val2 的方式进行编码，
key和val都进行 URL转码。

redata = urlencode(redata)