Web API 下的 ActionFilter 与 ExceptionFilter

本文重点会标红。

背景需求，在进入action之前做sign验证，以及反正错误时，记录log，返回错误的json形式信息。

#region  普通 ActionFilter add by caoheyang 20150319



    /// <summary>

    /// sign 以及参数合法性验证过滤器 add by caoheyang 20150318

    /// </summary>

    public class SignOpenApiAttribute : System.Web.Http.Filters.ActionFilterAttribute

    {

        /// <summary>

        /// 重写OnActionExecuting方法   在进入控制器之前验证 sign以及 参数合法性信息 add by caoheyang 20150318

        /// </summary>

        /// <param name="actionContext"></param>

        public override void OnActionExecuting(System.Web.Http.Controllers.HttpActionContext actionContext)

        {

            lock (actionContext)

            {

                dynamic paramodel = actionContext.ActionArguments["paramodel"]; //当前请求的参数对象 

                if (actionContext.ModelState.Count > 0 || paramodel == null) //参数错误，请求中止

                    actionContext.Response = actionContext.ActionDescriptor.ResultConverter.Convert

                            (actionContext.ControllerContext, ResultModel<object>.Conclude(OrderApiStatusType.ParaError));

                IGroupProvider groupProvider = new GroupProvider();

                GroupApiConfigModel groupCofigInfo = groupProvider.GetGroupApiConfigByAppKey(paramodel.app_key, paramodel.v).Data;

                if (groupCofigInfo != null && groupCofigInfo.IsValid == 1)//集团可用，且有appkey信息

                {

                    string signStr = groupCofigInfo.AppSecret + "app_key=" + paramodel.app_key + "timestamp" + paramodel.timestamp + "v=" + paramodel.v + groupCofigInfo.AppSecret;

                    string sign = MD5.Encrypt(signStr);

                    paramodel.group = ParseHelper.ToInt(groupCofigInfo.GroupId, 0);

                    actionContext.ActionArguments["paramodel"] = paramodel; ;

                    if (sign != paramodel.sign)   //sign错误，请求中止

                        actionContext.Response = actionContext.ActionDescriptor.ResultConverter.Convert

                            (actionContext.ControllerContext, ResultModel<object>.Conclude(OrderApiStatusType.SignError)); //此处标红需要与 apicontroller里应用fillter的action返回值一直。

                }

                else

                    actionContext.Response = actionContext.ActionDescriptor.ResultConverter.Convert

                           (actionContext.ControllerContext, ResultModel<object>.Conclude(OrderApiStatusType.SignError));  //sign错误，请求中止

            }

        }

    }



    #endregion



    #region  ExceptionFilter add by caoheyang 20150319



    /// <summary>

    /// 自定义全局异常处理类  add by caoheyang 20150319   全局过滤器，记录log /// </summary>

    public class OpenApiHandleErrorAttribute : ExceptionFilterAttribute

    {

        /// <summary>

        /// 重写异常处理方法 add by caoheyang 20150205  其次执行 /// </summary>

        /// <param name="filterContext">上下文对象  该类继承于ControllerContext</param>

        public override void OnException(HttpActionExecutedContext filterContext)

        {

            LogHelper.LogWriterFromFilter(filterContext.Exception);

        }

    }



    /// <summary>  action过滤器，当内部代码发生异常时，改变当前的请求服务器端返回信息

    /// 自定义action异常处理类,捕获异常，返回系统错误提示信息  add by caoheyang 20150319

    /// </summary>

    public class OpenApiActionErrorAttribute : ExceptionFilterAttribute

    {

        /// <summary>

        /// 重写异常处理方法 add by caoheyang 20150205   首先执行  

        /// </summary>

        /// <param name="filterContext">上下文对象  该类继承于ControllerContext</param>

        public override void OnException(HttpActionExecutedContext filterContext)

        {

            filterContext.Response = filterContext.ActionContext.ActionDescriptor.ResultConverter.

              Convert(filterContext.ActionContext.ControllerContext, ResultModel<object>.Conclude(OrderApiStatusType.SystemError));

            //此处标红需要与 apicontroller里应用fillter的action返回值一直。

} } #endregion

ApiController eg。

 // POSR: Order GetStatus    paramodel 固定 必须是 paramodel

        /// <summary>

        /// 订单状态查询功能  add by caoheyang 20150316

        /// </summary>

        /// <returns></returns>

        [HttpPost]

        [SignOpenApi] //sign验证过滤器 设计参数验证，sign验证 add by caoheyang 201503167

        [OpenApiActionError] //异常过滤器 add by caoheyang 一旦发生异常，客户端返回系统内部错误提示

        public ResultModel<object> GetStatus(ParaModel<GetStatusPM_OpenApi> paramodel)

        {

          

        }