支付宝支付流程

  1 from datetime import datetime
  2 from Crypto.PublicKey import RSA
  3 from Crypto.Signature import PKCS1_v1_5
  4 from Crypto.Hash import SHA256
  5 from urllib.parse import quote_plus
  6 from urllib.parse import urlparse, parse_qs
  7 from base64 import decodebytes, encodebytes
  8 import json
  9 
 10 class AliPay(object):
 11     """
 12     支付宝支付接口(PC端支付接口)
 13     """
 14 
 15     def __init__(self, appid, app_notify_url, app_private_key_path,
 16                  alipay_public_key_path, return_url, debug=False):
 17         self.appid = appid
 18         self.app_notify_url = app_notify_url
 19         self.app_private_key_path = app_private_key_path
 20         self.app_private_key = None
 21         self.return_url = return_url
 22         with open(self.app_private_key_path) as fp:
 23             self.app_private_key = RSA.importKey(fp.read())
 24         self.alipay_public_key_path = alipay_public_key_path
 25         with open(self.alipay_public_key_path) as fp:
 26             self.alipay_public_key = RSA.importKey(fp.read())
 27 
 28         if debug is True:
 29             self.__gateway = "https://openapi.alipaydev.com/gateway.do"
 30         else:
 31             self.__gateway = "https://openapi.alipay.com/gateway.do"
 32 
 33     def direct_pay(self, subject, out_trade_no, total_amount, return_url=None, **kwargs):
 34         biz_content = {
 35             "subject": subject,
 36             "out_trade_no": out_trade_no,
 37             "total_amount": total_amount,
 38             "product_code": "FAST_INSTANT_TRADE_PAY",
 39             # "qr_pay_mode":4
 40         }
 41 
 42         biz_content.update(kwargs)
 43         data = self.build_body("alipay.trade.page.pay", biz_content, self.return_url)
 44         return self.sign_data(data)
 45 
 46     def build_body(self, method, biz_content, return_url=None):
 47         data = {
 48             "app_id": self.appid,
 49             "method": method,
 50             "charset": "utf-8",
 51             "sign_type": "RSA2",
 52             "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
 53             "version": "1.0",
 54             "biz_content": biz_content
 55         }
 56 
 57         if return_url is not None:
 58             data["notify_url"] = self.app_notify_url
 59             data["return_url"] = self.return_url
 60 
 61         return data
 62 
 63     def sign_data(self, data):
 64         data.pop("sign", None)
 65         # 排序后的字符串
 66         unsigned_items = self.ordered_data(data)
 67         unsigned_string = "&".join("{0}={1}".format(k, v) for k, v in unsigned_items)
 68         sign = self.sign(unsigned_string.encode("utf-8"))
 69         # ordered_items = self.ordered_data(data)
 70         quoted_string = "&".join("{0}={1}".format(k, quote_plus(v)) for k, v in unsigned_items)
 71 
 72         # 获得最终的订单信息字符串
 73         signed_string = quoted_string + "&sign=" + quote_plus(sign)
 74         return signed_string
 75 
 76     def ordered_data(self, data):
 77         complex_keys = []
 78         for key, value in data.items():
 79             if isinstance(value, dict):
 80                 complex_keys.append(key)
 81 
 82         # 将字典类型的数据dump出来
 83         for key in complex_keys:
 84             data[key] = json.dumps(data[key], separators=(‘,‘, ‘:‘))
 85 
 86         return sorted([(k, v) for k, v in data.items()])
 87 
 88     def sign(self, unsigned_string):
 89         # 开始计算签名
 90         key = self.app_private_key
 91         signer = PKCS1_v1_5.new(key)
 92         signature = signer.sign(SHA256.new(unsigned_string))
 93         # base64 编码，转换为unicode表示并移除回车
 94         sign = encodebytes(signature).decode("utf8").replace("\n", "")
 95         return sign
 96 
 97     def _verify(self, raw_content, signature):
 98         # 开始计算签名
 99         key = self.alipay_public_key
100         signer = PKCS1_v1_5.new(key)
101         digest = SHA256.new()
102         digest.update(raw_content.encode("utf8"))
103         if signer.verify(digest, decodebytes(signature.encode("utf8"))):
104             return True
105         return False
106 
107     def verify(self, data, signature):
108         if "sign_type" in data:
109             sign_type = data.pop("sign_type")
110         # 排序后的字符串
111         unsigned_items = self.ordered_data(data)
112         message = "&".join(u"{}={}".format(k, v) for k, v in unsigned_items)
113         return self._verify(message, signature)