Chilkat2-Python HTTP表单认证问题：转换请求后返回403 Forbidden

原Requests实现代码 #

import requests

data = {"username": "user","password": "pass","remember": "on"}

sign_in_url = 'https://www.tradingview.com/accounts/signin/'
signin_headers = {'Referer': 'https://www.tradingview.com'}

response = requests.post(url=sign_in_url, data=data, headers=signin_headers)
token = response.json()['user']['auth_token']

注：凭证错误时，原请求返回状态码200，响应内容：b'{"error":"Invalid username or password","code":"invalid_credentials"}'

问题代码（Chilkat2实现，返回403 Forbidden） #

http = chilkat2.Http()
req = chilkat2.HttpRequest()
req.AddParam("username","user")
req.AddParam("password","pass")
req.AddParam("remember","on")
req.Path = '/accounts/signin/'

req.HttpVerb = "POST"
http.FollowRedirects = True

http.SendCookies = True
http.SaveCookies = True
http.CookieDir = "memory"


resp = http.SynchronousRequest('www.tradingview.com',443,True,req)
print(http.LastErrorText)

错误原因及修复方案 #

返回403的核心原因是缺少原Requests代码中设置的Referer请求头，TradingView服务器会验证请求来源，无Referer的请求会被判定为非法。

修复步骤： #

• 给Chilkat2的HttpRequest添加Referer头，与原Requests保持一致
• 确认请求的Content-Type匹配（Chilkat2添加表单参数后会自动设置为application/x-www-form-urlencoded，和Requests默认行为一致，无需额外修改）

修复后的完整代码：

http = chilkat2.Http()
req = chilkat2.HttpRequest()

# 添加表单参数
req.AddParam("username","user")
req.AddParam("password","pass")
req.AddParam("remember","on")

# 设置请求路径与方法
req.Path = '/accounts/signin/'
req.HttpVerb = "POST"

# 关键：添加Referer头
req.AddHeader("Referer", "https://www.tradingview.com")

# 保持Cookie相关配置
http.FollowRedirects = True
http.SendCookies = True
http.SaveCookies = True
http.CookieDir = "memory"

resp = http.SynchronousRequest('www.tradingview.com',443,True,req)
# 输出响应内容查看结果
if resp is not None:
    print(resp.BodyStr)
else:
    print(http.LastErrorText)

额外提示： #

若添加Referer后仍出现异常，可以补充设置User-Agent头模拟浏览器请求，示例：

req.AddHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36")

修复后即使凭证错误，也会返回与原Requests一致的200状态码及错误响应，而非403。

内容的提问来源于stack exchange，提问作者IlyaK