.net core webapi通过中间件获取请求和响应内容

本文主要根据中间件来实现对.net core webapi中产生的请求和响应数据进行获取并存入日志文件中；

这里不详细介绍日志文件的使用。你可以自己接入NLog,log4net，Exceptionless等

创建接口记录的中间件

using Microliu.Core.Loggers;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Http.Internal;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Ptibro.Partner.API.Extensions
{

    public class RequestResponseLoggingMiddleware
    {
        private readonly RequestDelegate _next;
        private readonly ILogger _logger;

        private SortedDictionary<string, object> _data;
        private Stopwatch _stopwatch;

        public RequestResponseLoggingMiddleware(RequestDelegate next, ILogger logger)
        {
            _next = next;
            _logger = logger;
            _stopwatch = new Stopwatch();
        }

        public async Task Invoke(HttpContext context)
        {
            _stopwatch.Restart();
            _data = new SortedDictionary<string, object>();

            HttpRequest request = context.Request;
            _data.Add("request.url", request.Path.ToString());
            _data.Add("request.headers", request.Headers.ToDictionary(x => x.Key, v => string.Join(";", v.Value.ToList())));
            _data.Add("request.method", request.Method);
            _data.Add("request.executeStartTime", DateTimeOffset.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));

            // 获取请求body内容
            if (request.Method.ToLower().Equals("post"))
            {
                // 启用倒带功能，就可以让 Request.Body 可以再次读取
                request.EnableRewind();

                Stream stream = request.Body;
                byte[] buffer = new byte[request.ContentLength.Value];
                stream.Read(buffer, , buffer.Length);
                _data.Add("request.body", Encoding.UTF8.GetString(buffer));

                request.Body.Position = ;
            }
            else if (request.Method.ToLower().Equals("get"))
            {
                _data.Add("request.body", request.QueryString.Value);
            }

            // 获取Response.Body内容
            var originalBodyStream = context.Response.Body;

            using (var responseBody = new MemoryStream())
            {
                context.Response.Body = responseBody;

                await _next(context);

                _data.Add("response.body", await GetResponse(context.Response));
                _data.Add("response.executeEndTime", DateTimeOffset.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));

                await responseBody.CopyToAsync(originalBodyStream);
            }

            // 响应完成记录时间和存入日志
            context.Response.OnCompleted(() =>
            {
                _stopwatch.Stop();
                _data.Add("elaspedTime", _stopwatch.ElapsedMilliseconds + "ms");
                var json = JsonConvert.SerializeObject(_data);
                _logger.Debug(json, "api", request.Method.ToUpper());
                return Task.CompletedTask;
            });

        }

        /// <summary>
        /// 获取响应内容
        /// </summary>
        /// <param name="response"></param>
        /// <returns></returns>
        public async Task<string> GetResponse(HttpResponse response)
        {
            response.Body.Seek(, SeekOrigin.Begin);
            var text = await new StreamReader(response.Body).ReadToEndAsync();
            response.Body.Seek(, SeekOrigin.Begin);
            return text;
        }
    }

    /// <summary>
    /// 扩展中间件
    /// </summary>
    public static class RequestResponseLoggingMiddlewareExtensions
    {
        public static IApplicationBuilder UseRequestResponseLogging(this IApplicationBuilder app)
        {
            return app.UseMiddleware<RequestResponseLoggingMiddleware>();
        }
    }

}

在startup.cs中Configure方法中使用中间件

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseErrorHandling();// 全局异常尽量放上面
            ...
            app.UseRequestResponseLogging();
            ...
            app.UseExceptionless(Configuration);
            app.UseMvc();
        }

现在请求一次看一下记录的效果：我的日志存在exceptionless上，如下图

解析json，记录的数据如下：

参考地址：https://www.cnblogs.com/wybin6412/p/10944077.html （我只是在此基础上进行了一些小的改善）