using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using System.Threading.Tasks;
using System;
using System.Text.Json;
using Microsoft.AspNetCore.Builder;

namespace Wms_09.Filter
{
    public class CustomerExceptionMiddleware
    {
        /// <summary>
        /// 委托
        /// </summary>
        private readonly RequestDelegate _next;

        public CustomerExceptionMiddleware(RequestDelegate next)
        {
            _next = next;
        }

        public async Task Invoke(HttpContext context)
        {
            try
            {
                await _next(context);
            }
            catch (Exception ex)
            {

                context.Response.ContentType = "application/json";

                var result = new { code = 1, msg = "系统异常" };

                var stream = context.Response.Body;
                await JsonSerializer.SerializeAsync(stream, result);
            }
        }
    }

    /// <summary>
    /// 静态类
    /// </summary>
    public static class ExceptionMiddlewareExtension
    {
        /// <summary>
        /// 静态方法
        /// </summary>
        /// <param name="app">要进行扩展的类型</param>
        public static void UseExceptionMiddleware(this IApplicationBuilder app)
        {
            app.UseMiddleware(typeof(CustomerExceptionMiddleware));
        }
    }
}