-- coding: utf-8 --

pip install pycryptodome

author = ‘bobby’

from datetime import datetime
from Crypto.PublicKey import RSA
from Crypto.Signature import PKCS1_v1_5
from Crypto.Hash import SHA256
from base64 import b64encode, b64decode
from urllib.parse import quote_plus
from urllib.parse import urlparse, parse_qs
from urllib.request import urlopen
from base64 import decodebytes, encodebytes

import json

class AliPay(object):
""“
支付宝支付接口
”""

def __init__(self, appid, app_notify_url, app_private_key_path,
             alipay_public_key_path, return_url, debug=False):
    self.appid = appid
    self.app_notify_url = app_notify_url
    self.app_private_key_path = app_private_key_path
    self.app_private_key = None
    self.return_url = return_url
    with open(self.app_private_key_path) as fp:
        self.app_private_key = RSA.importKey(fp.read())

    self.alipay_public_key_path = alipay_public_key_path
    with open(self.alipay_public_key_path) as fp:
        self.alipay_public_key = RSA.import_key(fp.read())

    if debug is True:
        self.__gateway = "https://openapi.alipaydev.com/gateway.do"
    else:
        self.__gateway = "https://openapi.alipay.com/gateway.do"

def direct_pay(self, subject, out_trade_no, total_amount, return_url=None, **kwargs):
    biz_content = {
        "subject": subject,
        "out_trade_no": out_trade_no,
        "total_amount": total_amount,
        "product_code": "FAST_INSTANT_TRADE_PAY",
        # "qr_pay_mode":4
    }

    biz_content.update(kwargs)
    data = self.build_body("alipay.trade.page.pay", biz_content, self.return_url)
    return self.sign_data(data)

def build_body(self, method, biz_content, return_url=None):
    data = {
        "app_id": self.appid,
        "method": method,
        "charset": "utf-8",
        "sign_type": "RSA2",
        "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
        "version": "1.0",
        "biz_content": biz_content
    }

    if return_url is not None:
        data["notify_url"] = self.app_notify_url
        data["return_url"] = self.return_url

    return data

def sign_data(self, data):
    data.pop("sign", None)
    # 排序后的字符串
    unsigned_items = self.ordered_data(data)
    unsigned_string = "&".join("{0}={1}".format(k, v) for k, v in unsigned_items)
    sign = self.sign(unsigned_string.encode("utf-8"))
    # ordered_items = self.ordered_data(data)
    quoted_string = "&".join("{0}={1}".format(k, quote_plus(v)) for k, v in unsigned_items)

    # 获得最终的订单信息字符串
    signed_string = quoted_string + "&sign=" + quote_plus(sign)
    return signed_string

def ordered_data(self, data):
    complex_keys = []
    for key, value in data.items():
        if isinstance(value, dict):
            complex_keys.append(key)

    # 将字典类型的数据dump出来
    for key in complex_keys:
        data[key] = json.dumps(data[key], separators=(',', ':'))

    return sorted([(k, v) for k, v in data.items()])

def sign(self, unsigned_string):
    # 开始计算签名
    key = self.app_private_key
    signer = PKCS1_v1_5.new(key)
    signature = signer.sign(SHA256.new(unsigned_string))
    # base64 编码，转换为unicode表示并移除回车
    sign = encodebytes(signature).decode("utf8").replace("\n", "")
    return sign

def _verify(self, raw_content, signature):
    # 开始计算签名
    key = self.alipay_public_key
    signer = PKCS1_v1_5.new(key)
    digest = SHA256.new()
    digest.update(raw_content.encode("utf8"))
    if signer.verify(digest, decodebytes(signature.encode("utf8"))):
        return True
    return False

def verify(self, data, signature):
    if "sign_type" in data:
        sign_type = data.pop("sign_type")
    # 排序后的字符串
    unsigned_items = self.ordered_data(data)
    message = "&".join(u"{}={}".format(k, v) for k, v in unsigned_items)
    return self._verify(message, signature)

if name == “main”:
return_url = 'http://127.0.0.1:8000/?total_amount=100.00&timestamp=2017-08-15+23%3A53%3A34&sign=e9E9UE0AxR84NK8TP1CicX6aZL8VQj68ylugWGHnM79zA7BKTIuxxkf%2FvhdDYz4XOLzNf9pTJxTDt8tTAAx%2FfUAJln4WAeZbacf1Gp4IzodcqU%2FsIc4z93xlfIZ7OLBoWW0kpKQ8AdOxrWBMXZck%2F1cffy4Ya2dWOYM6Pcdpd94CLNRPlH6kFsMCJCbhqvyJTflxdpVQ9kpH%2B%2Fhpqrqvm678vLwM%2B29LgqsLq0lojFWLe5ZGS1iFBdKiQI6wZiisBff%2BdAKT9Wcao3XeBUGigzUmVyEoVIcWJBH0Q8KTwz6IRC0S74FtfDWTafplUHlL%2Fnf6j%2FQd1y6Wcr2A5Kl6BQ%3D%3D&trade_no=2017081521001004340200204115&sign_type=RSA2&auth_app_id=2016080600180695&charset=utf-8&seller_id=2088102170208070&method=alipay.trade.page.pay.return&app_id=2016080600180695&out_trade_no=20170202185&version=1.0’
o = urlparse(return_url)
query = parse_qs(o.query)
processed_query = {}
ali_sign = query.pop(“sign”)[0]

alipay = AliPay(
    appid="***",
    app_notify_url="http://127.0.0.1:8000/alipay/return/",
    app_private_key_path="../trade/keys/app_private_key.pem",
    alipay_public_key_path="../trade/keys/alipay_pub_key.pem",  # 支付宝的公钥，验证支付宝回传消息使用，不是你自己的公钥,
    debug=True,  # 默认False,
    return_url="http://127.0.0.1:8000/alipay/return/"
)

for key, value in query.items():
    processed_query[key] = value[0]
print(alipay.verify(processed_query, ali_sign))

url = alipay.direct_pay(
    subject="测试订单2",
    out_trade_no="20170202ssggws",
    total_amount=100,
    return_url="http://127.0.0.1:8000/alipay/return/"
)
re_url = "https://openapi.alipaydev.com/gateway.do?{data}".format(data=url)

print(re_url)
就是这个代码验签不通，如果不验签，可以正常生成支付的链接，沙箱环境！