ASP .NET Core Api使用过滤器

Asp.net webapi 为我们提供的 ActionFilterAttribute 拦截器，通过 重写 OnActionExecuting，来 拦截action的请求消息，当执行OnActionExecuting完成以后才真正进入请求的action中，action运行完后又把控制权给了 OnActionExecuted，这个管道机制可以使我们用它来轻松实现 权限认证、日志记录 ，跨域以及很多需要对全局或者部分请求做手脚的的功能。
大概的流程如下：

asp.net core 里面的过滤器有这么多：

• IActionFilter
• IResourceFilter
• IResultFilter
• IAuthorizationFilter
• IPageFilter
• IExceptionFilter
• ActionFilterAttribute

获取Api请求相关信息

using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Razor.TagHelpers;
using Microsoft.AspNetCore.Mvc.Controllers;
using System.Text;
using System.Text.Json;

namespace WebApplication1
{
    //[AttributeUsage(AttributeTargets.Method, AllowMultiple = false)]//方法级别
    public class ApiFilter : ActionFilterAttribute
    {

        private string ActionArguments { get; set; }
        private readonly ILogger<ApiFilter> _logger;
        private readonly IServiceProvider _serviceProvider;
        public ApiFilter(ILogger<ApiFilter> logger, IServiceProvider serviceProvider)
        {
            _logger = logger;
            _serviceProvider = serviceProvider;
        }

        /// <summary>
        /// 执行方法体之后,返回result前
        /// </summary>
        /// <param name="context"></param>
        public override void OnActionExecuted(ActionExecutedContext context)
        {

            var request = context?.HttpContext?.Request;

            //请求地址
            string url = request.Host + request.Path + request.QueryString;

            var descriptor = (ControllerActionDescriptor)context.ActionDescriptor;
            //获取控制器名称
            var controllerName = descriptor.ControllerName;
            //获取action名称
            var actionName = descriptor.ActionName;
            //获取request参数
            var requestArguments = ActionArguments;
            //请求方式
            string method = request.Method;
            //请求Header
            var headrs = request.Headers;
            //context.HttpContext.Request.Form

            //Response
            var Response = context?.HttpContext?.Response;
            var result = context.Result;
            if (result is JsonResult json)
            {
                var x = json.Value;
                var status = json.StatusCode;
                var content = JsonSerializer.Serialize(x);
            }
            if (result is ViewResult view)
            {
                var status = view.StatusCode;
                var x = view.ViewData;
                var name = view.ViewName;
            }
            if (result is ObjectResult ob)
            {
                var x = ob.Value;
                var status = ob.StatusCode;
                var content = JsonSerializer.Serialize(x);
            }

            base.OnActionExecuted(context);

        }

        /// <summary>
        /// 执行方法体之前
        /// </summary>
        /// <param name="context"></param>
        public override void OnActionExecuting(ActionExecutingContext context)
        {
            try
            {
                if (context.ActionArguments != null && context.ActionArguments.Count > 0)
                {
                    ActionArguments = JsonSerializer.Serialize(context.ActionArguments);
                }
                else
                {
                    ActionArguments = string.Empty;
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex.StackTrace);
            }

            base.OnActionExecuting(context);
        }

        /// <summary>
        /// 返回result之前
        /// </summary>
        /// <param name="context"></param>
        public override void OnResultExecuting(ResultExecutingContext context)
        {
            base.OnResultExecuting(context);
        }

        /// <summary>
        /// 返回result之后
        /// </summary>
        /// <param name="context"></param>
        public override void OnResultExecuted(ResultExecutedContext context)
        {
            base.OnResultExecuted(context);
        }
    }
}

Exception记录日志

using Microsoft.AspNetCore.Mvc.Filters;
using System.Text.Json;

namespace WebApplication1
{
    public class ExceptionFilter : ActionFilterAttribute
    {
        private string ActionArguments { get; set; }
        private readonly ILogger<ApiFilter> _logger;
        private readonly IServiceProvider _serviceProvider;
        public ExceptionFilter(ILogger<ApiFilter> logger, IServiceProvider serviceProvider)
        {
            _logger = logger;
            _serviceProvider = serviceProvider;
        }

        /// <summary>
        /// 执行方法体之后,返回result前
        /// </summary>
        /// <param name="context"></param>
        public override void OnActionExecuted(ActionExecutedContext context)
        {
            if (context.Exception != null)
            {
                LoggerError(context, context.Exception);
            }

            base.OnActionExecuted(context);
        }

        /// <summary>
        /// 执行方法体之前
        /// </summary>
        /// <param name="context"></param>
        public override void OnActionExecuting(ActionExecutingContext context)
        {
            try
            {
                if (context.ActionArguments != null && context.ActionArguments.Count > 0)
                {
                    ActionArguments = JsonSerializer.Serialize(context.ActionArguments);
                }
                else
                {
                    ActionArguments = string.Empty;
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex.StackTrace);
            }

            base.OnActionExecuting(context);
        }


        private void LoggerError(ActionExecutedContext context, Exception exception)
        {
            try
            {
                string url = context.HttpContext.Request.Host + context.HttpContext.Request.Path + context.HttpContext.Request.QueryString;
                string method = context.HttpContext.Request.Method;
                string message = $"\n" + $"地址：{url} \n " +
                $"方式：{method} \n " +
                $"参数：{ActionArguments}\n " +
                $"错误描述：{context.Exception.Message}\n " +
                $"错误堆栈：{context.Exception.StackTrace}\n ";
                if (exception.InnerException != null)
                {
                    message += "\n InnerException异常Message：" + exception.InnerException.Message;
                    message += "\n InnerException异常StackTrace：" + exception.InnerException.StackTrace;
                }
                _logger.LogError(message);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex.StackTrace);
            }
        }
    }
}

添加过滤器

在Program.cs添加Filter

builder.Services.AddControllers(options =>
{
    //options.Filters.Add(new ApiFilter(null,null));
    options.Filters.Add<ApiFilter>();
});