前端开发调试的时候，通常是localhost，而接口不在本机，会有跨域问题。通过http.server 实现的请求代理，解决了跨域问题并且实现登录。

class MyRequestHandler(SimpleHTTPRequestHandler):

    def addHeader(self):
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Headers", "*")
        self.send_header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE")
        self.send_header("Content-type", "text/html")

    def do_GET(self):
        print('Get请求：'+self.path)
        rep_get = requests.get(serverurl + self.path, cookies=cookie_jar)
        if rep_get.status_code == 200:
            self.send_response(200)
            self.addHeader()
            self.end_headers()
            self.wfile.write(rep_get.text.encode("utf-8"))
        else:
            self.Login()
            rep_get = requests.get(serverurl + self.path, cookies=cookie_jar)
            self.send_response(200)
            self.addHeader()
            self.end_headers()
            self.wfile.write(rep_get.text.encode("utf-8"))

    def do_POST(self):
        print('Post请求：'+self.path)
        request_contentType = str(self.headers["Content-Type"])
        if request_contentType.find('application/x-www-form-urlencoded')>-1:
            data = str(self.rfile.read(int(self.headers["content-length"])),'UTF-8')

            #data = str(self.rfile.readlines(), 'UTF-8')  # 先解码
            p1 = urllib.parse.parse_qs(urllib.parse.unquote(data))  # 解释参数
            rel_par={}
            for it in p1:
                rel_par[it]=p1[it][0]

            rep_post = requests.post(serverurl + self.path, cookies=cookie_jar,data=rel_par)
            if rep_post.status_code==200:

                self.send_response(200)
                self.addHeader()
                self.end_headers()
                self.wfile.write(rep_post.text.encode("utf-8"))
            else:
                self.Login()
                rep_post = requests.post(serverurl + self.path, cookies=cookie_jar, data=rel_par)
                self.send_response(200)
                self.addHeader()
                self.end_headers()
                self.wfile.write(rep_post.text.encode("utf-8"))

        else:
            req = {"success": "false", "message": "暂时只支持Content-Type=application/x-www-form-urlencoded"}
            self.send_response(200)
            self.addHeader()
            self.end_headers()
            rspstr = json.dumps(req)
            self.wfile.write(rspstr.encode("utf-8"))

    def Login(self):
        isLogin =True
        req_login1 = requests.post(serverurl + '/SUP/Login/WebLogin',data={
            'ocode': '',
            'UserID': user,
            'UserPwd': pwd,
            'DataBase': ucode,
            'Language': "zh-CN",
            'verifyCode': ""
        })
        if req_login1.status_code == 200:
            if req_login1.text.find('success: true') > 0:
                globals()['cookie_jar']=req_login1.cookies
            else:
                i1 = req_login1.text.find('msg')
                km = json.loads(req_login1.text[i1 + 5:-2])
                if km != None:
                    print('开始踢人')
                    req_kill = requests.post(serverurl + '/SUP/Login/KillOnlineUser', data={
                        'IpAddress': km['IpAddress'],
                        'Devicetype': km['Devicetype'],
                        'UserId': km['UserId'],
                        'SessionID': km['SessionID']
                    })
                    if req_kill.status_code == 200:
                        print('踢人成功，重新登录')
                        req_login2 = requests.post(serverurl + '/SUP/Login/WebLogin', data={
                            'ocode': '',
                            'UserID': user,
                            'UserPwd': pwd,
                            'DataBase': ucode,
                            'Language': "zh-CN",
                            'verifyCode': "",
                            'IsOnlineCheck': '1'
                        })
                        if req_login2.status_code == 200:
                            globals()['cookie_jar'] = req_login2.cookies
                        else:
                            isLogin = False
                            print('踢人以后登录返回错误，请检查服务器是否可访问')
                    else:
                        isLogin = False
                        print('踢人接口错误，请检查服务器是否可访问')
                else:
                    isLogin = False
                    print('登录返回错误，请检查服务器是否可访问')
        else:
            isLogin = False
            print('服务器登录返回错误，请检查服务器是否可访问')
        return isLogin

使用：

try:
    config = configparser.ConfigParser()
    isread = config.read('ngproxy.ini')
    if len(isread) == 0:
        serverurl = input("请输入服务器url: ")
        ucode = input("请输入服务器账套: ")
        user = input("请输入服务器用户: ")
        pwd = input("请输入服务器密码: ")
        port = input("请输入代理端口: ")

        config.add_section('userinfo')
        config.set('userinfo', 'serverurl', serverurl)
        config.set('userinfo', 'username', user)
        config.set('userinfo', 'password', pwd)
        config.set('userinfo', 'ucode', ucode)
        config.set('userinfo', 'port', port)
        f = open('ngproxy.ini', "w")
        config.write(f)  # 写进文件
        f.close()
    else:
        serverurl = config['userinfo']['serverurl']
        user = config['userinfo']['username']
        pwd = config['userinfo']['password']
        ucode = config['userinfo']['ucode']
        port = config['userinfo']['port']
    bytes_user=user.encode()
    user = str(base64.b64encode(bytes_user), 'utf-8')

    bytes_pwd = pwd.encode()
    pwd = base64.b64encode(bytes_pwd)
    pwd = str(pwd, 'utf-8')

    cookie_jar = RequestsCookieJar()

    server = HTTPServer(("", int(port)), MyRequestHandler)
    print("代理服务器启动成功, serving at http://localhost:" + port)
    server.serve_forever()