微信公众平台开发利器-weixin-knife(Python版)

    这两天将之前基于微信公众平台的代码重构了下，基础功能以库的方式提供，提供了demo使用的是django，看着之前为赶

进度写的代码真的惨不忍睹，所以weixin-knife产生了，正如其名，提供的是必要的功能，而不是完整的应用。weixin-knife可

以很方便的处理关注，取关注事件，处理文本消息，回复用户信息，jssdk处理，oauth认证，以及微信支付。

github地址：https://github.com/Skycrab/weixin-knife。

首先看看怎么用

from .weixin import handler as HD
@HD.subscribe
def subscribe(xml):
    return "welcome to brain"

@HD.unsubscribe
def subscribe(xml):
    print "leave"
    return "leave  brain"

处理文本消息，回复图文消息如下：

@HD.text
def text(xml):
    content = xml.Content
    if content == "111":
        return {"Title":"美女", "Description":"比基尼美女", "PicUrl":"http://9smv.com/static/mm/uploads/150411/2-150411115450247.jpg", "Url":"http://9smv.com/beauty/list?category=5"}
    elif content == "222":
        return [
            ["比基尼美女", "比基尼美女", "http://9smv.com/static/mm/uploads/150411/2-150411115450247.jpg", "http://9smv.com/beauty/list?category=5"],
            ["长腿美女", "长腿美女", "http://9smv.com/static/mm/uploads/150506/2-150506111A9648.jpg", "http://9smv.com/beauty/list?category=8"]
        ]
    elif content == "push":
        Helper.send_text_message(xml.FromUserName, "推送消息测试")
        return "push ok"

    return "hello world"

一般我们会使用oauth网页授权获取用户的openid，如果是多个链接都需要通过oauth处理，代码会很难看，通过装饰器可以很好的处理这个问题。

def sns_userinfo_callback(callback=None):
    """网页授权获取用户信息装饰器
    callback(openid, userinfo):
        return user
    """
    def wrap(func):
        @wraps(func)
        def inner(*args, **kwargs):
            request = args[0]  #django第一个参数request
            openid = request.COOKIES.get(‘openid‘)
            userinfo = None
            if not openid:
                code = request.GET.get("code")
                if not code:
                    current = "http://"+ request.get_host() + request.get_full_path()
                    return redirect(WeixinHelper.oauth2(current))
                else:
                    data = json.loads(WeixinHelper.getAccessTokenByCode(code))
                    access_token, openid, refresh_token = data["access_token"], data["openid"], data["refresh_token"]
                    #WeixinHelper.refreshAccessToken(refresh_token)
                    userinfo = json.loads(WeixinHelper.getSnsapiUserInfo(access_token, openid))
            else:
                ok, openid = Helper.check_cookie(openid)
                if not ok:
                    return redirect("/")
            request.openid = openid
            if callable(callback):
                request.user = callback(openid, userinfo)
            response = func(request)
            return response
        return inner
    return wrap

sns_userinfo = sns_userinfo_callback()

就可以使用request.user获取当前用户

@sns_userinfo
def oauth(request):
    """网页授权获取用户信息"""
    resp = HttpResponse(request.openid)
    resp.set_cookie("openid", Helper.sign_cookie(request.openid))
    return resp

weixin-knife提供了微信支付支持，稍微修改我之前移植的官方PHP版本，https://github.com/Skycrab/wzhifuSDK

@sns_userinfo
def pay(request):
    response = render_to_response("pay.html")
    response.set_cookie("openid", Helper.sign_cookie(request.openid))
    return response

@sns_userinfo
@catch
def paydetail(request):
    """获取支付信息"""
    openid = request.openid
    money = request.POST.get("money") or "0.01"
    money = int(float(money)*100)

    jsApi = JsApi_pub()
    unifiedOrder = UnifiedOrder_pub()
    unifiedOrder.setParameter("openid",openid) #商品描述
    unifiedOrder.setParameter("body","充值测试") #商品描述
    timeStamp = time.time()
    out_trade_no = "{0}{1}".format(WxPayConf_pub.APPID, int(timeStamp*100))
    unifiedOrder.setParameter("out_trade_no", out_trade_no) #商户订单号
    unifiedOrder.setParameter("total_fee", str(money)) #总金额
    unifiedOrder.setParameter("notify_url", WxPayConf_pub.NOTIFY_URL) #通知地址 
    unifiedOrder.setParameter("trade_type", "JSAPI") #交易类型
    unifiedOrder.setParameter("attach", "6666") #附件数据，可分辨不同商家(string(127))
    try:
        prepay_id = unifiedOrder.getPrepayId()
        jsApi.setPrepayId(prepay_id)
        jsApiParameters = jsApi.getParameters()
    except Exception as e:
        print(e)
    else:
        print jsApiParameters
        return HttpResponse(jsApiParameters)


FAIL, SUCCESS = "FAIL", "SUCCESS"
@catch
def payback(request):
    """支付回调"""
    xml = request.raw_post_data
    #使用通用通知接口
    notify = Notify_pub()
    notify.saveData(xml)
    print xml
    #验证签名，并回应微信。
    #对后台通知交互时，如果微信收到商户的应答不是成功或超时，微信认为通知失败，
    #微信会通过一定的策略（如30分钟共8次）定期重新发起通知，
    #尽可能提高通知的成功率，但微信不保证通知最终能成功
    if not notify.checkSign():
        notify.setReturnParameter("return_code", FAIL) #返回状态码
        notify.setReturnParameter("return_msg", "签名失败") #返回信息
    else:
        result = notify.getData()

        if result["return_code"] == FAIL:
            notify.setReturnParameter("return_code", FAIL)
            notify.setReturnParameter("return_msg", "通信错误")
        elif result["result_code"] == FAIL:
            notify.setReturnParameter("return_code", FAIL)
            notify.setReturnParameter("return_msg", result["err_code_des"])
        else:
            notify.setReturnParameter("return_code", SUCCESS)
            out_trade_no = result["out_trade_no"] #商户系统的订单号，与请求一致。
            ###检查订单号是否已存在,以及业务代码

    return  HttpResponse(notify.returnXml())

   $.post("/paydetail",{
      money: $momey
      },function(data){
        if(data){
          var jsonobj = eval(‘(‘+data+‘)‘);
          WeixinJSBridge.invoke(‘getBrandWCPayRequest‘, {
                 "appId" : jsonobj.appId, //公众号名称，由商户传入
                 "timeStamp" : jsonobj.timeStamp, //时间戳
                 "nonceStr" : jsonobj.nonceStr, //随机串
                 "package" : jsonobj.package,//扩展包
                 "signType" : "MD5", //微信签名方式:1.sha1
                 "paySign" : jsonobj.paySign //微信签名
                 });
        }
      }
    );

由于access_token， jsapi_ticket需要缓存，而缓存方式又依赖于具体环境，所以提供了一个Helper类，使用了django 的cache

缓存。

class Helper(object):
    """微信具体逻辑帮组类"""

    @class_property
    def access_token(cls):
        key = "ACCESS_TOKEN"
        token = cache.get(key)
        if not token:
            data = json.loads(WeixinHelper.getAccessToken())
            token, expire = data["access_token"], data["expires_in"]
            cache.set(key, token, expire-300)
        return token

    @class_property
    def jsapi_ticket(cls):
        key = "JSAPI_TICKET"
        ticket = cache.get(key)
        if not ticket:
            data = json.loads(WeixinHelper.getJsapiTicket(cls.access_token))
            ticket, expire = data["ticket"], data["expires_in"]
            cache.set(key, ticket, expire-300)
        return ticket

class class_property(object):
    """ A property can decorator class or instance

    class Foo(object):
        @class_property
        def foo(cls):
            return 42


    print(Foo.foo)
    print(Foo().foo)

    """
    def __init__(self, func, name=None, doc=None):
        self.__name__ = name or func.__name__
        self.__module__ = func.__module__
        self.__doc__ = doc or func.__doc__
        self.func = func

    def __get__(self, obj, type=None):
        value = self.func(type)
        return value