django-微信小程序登录

Posted 2021-01-31 zyxzyy

小程序登录逻辑
前端通过调用wx.login()获取code, 将code和用户基本信息发送到后端,后端通过request.get向微信服务器发送get请求获取用户openid和session_key,手动添加jwt-token,利用jwt自动校验用户是否登录

 

小程序前端触发login事件

<button class="confirm-btn"  open-type="getUserInfo" bindgetuserinfo="login" wx:if="{{regFlag==false}}">授权登录</button>

js代码：login事件接收的参数 e.detail.userInfo保存了用户基本信息，调用wxlogin方法获取用户的code，发送到后端

login:function( e ){
        var that = this;
        if( !e.detail.userInfo ){
            app.alert( { ‘content‘:‘登录失败，请再次点击~~‘ } );
            return;
        }

        var data = e.detail.userInfo;
        wx.login({
            success:function( res ){
                if( !res.code ){
                    app.alert( { ‘content‘:‘登录失败，请再次点击~~‘ } );
                    return;
                }
                data[‘code‘] = res.code;
                wx.request({
                    url:app.buildUrl( ‘/member/login‘ ),
                    header:app.getRequestHeader(),
                    method:‘POST‘,
                    data:data,
                    success:function( res ){
                        if( res.data.code != 200 ){
                            app.alert( { ‘content‘:res.data.msg } );
                            return;
                        }
                        app.setCache( "token",res.data.data.token );
                        that.goToIndex();
                    }
                });
            }
        });
    }

后端代码：

用户模型类继承自django自带的用户模型，新增三个用户信息字段

class User(AbstractUser):
    USER_GENDER_CHOICES = (
        (0, ‘女‘),
        (1, ‘男‘),
    )

    sex = models.SmallIntegerField(choices=USER_GENDER_CHOICES, default=1, verbose_name="性别")
    avatar = models.CharField(max_length=50, default="", null=True, blank=True, verbose_name="头像")
    openid = models.CharField(max_length=64, db_index=True, verbose_name=‘openid‘)

    class Meta:
        db_table = ‘tb_users‘
        verbose_name = ‘用户‘
        verbose_name_plural = verbose_name

类视图：发送请求获取用户的openid，用openid来查询是否用户已经存在，不存在创建信的用户，统一手动签发jwt_token返回

class WechatLoginView(APIView):
    """
    微信登录逻辑
    """

    def post(self, request):
        # 前端发送code到后端,后端发送网络请求到微信服务器换取openid
        code = request.data.get(‘code‘)
        if not code:
            return Response({‘message‘: ‘缺少code‘}, status=status.HTTP_400_BAD_REQUEST)

        url = "https://api.weixin.qq.com/sns/jscode2session?appid={0}&secret={1}&js_code={2}&grant_type=authorization_code"             .format(settings.APP_ID, settings.APP_KEY, code)
        r = requests.get(url)
        res = json.loads(r.text)
        openid = res[‘openid‘] if ‘openid‘ in res else None
        # session_key = res[‘session_key‘] if ‘session_key‘ in res else None
        if not openid:
            return Response({‘message‘: ‘微信调用失败‘}, status=status.HTTP_503)

        # 判断用户是否第一次登录
        try:
            user = User.objects.get(openid=openid)
        except Exception:
            # 微信用户第一次登陆,新建用户
            username = request.data.get(‘nickname‘)
            sex = request.data.get(‘sex‘)
            avatar = request.data.get(‘avatar‘)
            user = User.objects.create(username=username, sex=sex, avatar=avatar)
            user.set_password(openid)

        # 手动签发jwt
        jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
        jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER

        payload = jwt_payload_handler(user)
        token = jwt_encode_handler(payload)

        resp_data = {
            "user_id": user.id
            "username": user.username,
            "avatar": user.avatar,
            "token": token,
        }

        return Response(resp_data)
    

补充：jwt的配置

REST_FRAMEWORK = {
　　‘DEFAULT_AUTHENTICATION_CLASSES‘: (
　　‘rest_framework_jwt.authentication.JSONWebTokenAuthentication‘,
　　‘rest_framework.authentication.SessionAuthentication‘,
　　‘rest_framework.authentication.BasicAuthentication‘,
　　),
}

JWT_AUTH = {
　　# 指明token的有效期
　　‘JWT_EXPIRATION_DELTA‘: datetime.timedelta(days=7),
}