webapi日志记录（TXT存储）

记录webapi日志我使用了两种办法，一种是存储TXT的log文档，但我发现使用使用了我接口的日志都会存储到我电脑上。后面改用数据库存储log。数据库存储log信息这种方法个人比较推荐。之前花费了一些时间来写TXT存储还是想记录下来。

转载自：https://blog.csdn.net/lordwish/article/details/72353851

1、引用NLog类库

打开项目的NuGet包管理器，搜索NLog，为项目添加程序包引用。

2、修改项目配置文件

在webAPI项目的Web.config中进行NLog的配置。首先在节点configuration>configSections下添加节点：

此处name必需为nlog，否则配置信息将不能被读取。 然后在configuration节点下添加节点nlog：

这里定义了日志文件的保存路径、命名格式以及日志记录类型和监听级别。

 注意：<configSections>必须要紧跟在<configuration>下方

<configuration>
   <configSections>
      <section name="nlog" type="NLog.Config.ConfigSectionHandler,NLog" />
    </configSections>

  <nlog xmlns:xsi="http://www.w3.org/2001/XMLSchema">
    <targets>
      <target name="logfile" xsi:type="File" fileName="${basedir}/LogFile/${date:format=yyyy/MM/dd}-api.txt"/>
      <target name="eventlog" xsi:type="EventLog" layout="${message}" log="Application" source="Api Services"/>
    </targets>
    <rules>
      <logger name="*" minlevel="Trace" writeTo="logfile"/>
      <logger name="*" minlevel="Trace" writeTo="eventlog"/>
    </rules>    
  </nlog>
</configuration>

 3、创建日志及跟踪类

创建日志跟踪类AppLog，继承于System.Web.Http.Tracing下的跟踪编写器接口ITraceWriter，用于日志生成和写入：

using Newtonsoft.Json;
using NLog;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Web;
using System.Web.Http.Tracing;

namespace InsideMesAPI.Log
{
    public sealed class AppLog : ITraceWriter
    {
        //日志写入
        private static readonly Logger AppLogger = LogManager.GetCurrentClassLogger();
        private static readonly Lazy<Dictionary<TraceLevel, Action<string>>> LoggingMap = new Lazy<Dictionary<TraceLevel, Action<string>>>(() => new Dictionary<TraceLevel, Action<string>>
        {
            {TraceLevel.Info,AppLogger.Info },
            {TraceLevel.Debug,AppLogger.Debug },
            {TraceLevel.Error,AppLogger.Error },
            {TraceLevel.Fatal,AppLogger.Fatal },
            {TraceLevel.Warn,AppLogger.Warn }
        });


        private Dictionary<TraceLevel, Action<string>> Logger
        {
            get { return LoggingMap.Value; }
        }
        /// <summary>
        /// 跟踪编写器接口实现
        /// </summary>
        /// <param name="request"></param>
        /// <param name="category"></param>
        /// <param name="level"></param>
        /// <param name="traceAction"></param>
        public void Trace(HttpRequestMessage request, string category, TraceLevel level, Action<TraceRecord> traceAction)
        {
            if (level != TraceLevel.Off)//未禁用日志跟踪
            {
                if (traceAction != null && traceAction.Target != null)
                {
                    category = category + Environment.NewLine + "Action Parameters : " + JsonConvert.SerializeObject(traceAction.Target);
                }
                var record = new TraceRecord(request, category, level);
                if (traceAction != null)
                {
                    traceAction(record);
                }
                //  traceAction?.Invoke(record);
                Log(record);
            }
            //throw new NotImplementedException();
        }
        /// <summary>
        /// 日志写入
        /// </summary>
        /// <param name="record"></param>
        private void Log(TraceRecord record)
        {
            var message = new StringBuilder();

            /**************************运行日志****************************/

            if (!string.IsNullOrWhiteSpace(record.Message))
            {
                message.Append("").Append(record.Message + Environment.NewLine);
            }

            if (record.Request != null)
            {
                if (record.Request.Method != null)
                {
                    message.Append("Method : " + record.Request.Method + Environment.NewLine);
                }

                if (record.Request.RequestUri != null)
                {
                    message.Append("").Append("URL : " + record.Request.RequestUri + Environment.NewLine);
                }

                if (record.Request.Headers != null && record.Request.Headers.Contains("Token") && record.Request.Headers.GetValues("Token") != null && record.Request.Headers.GetValues("Token").FirstOrDefault() != null)
                {
                    message.Append("").Append("Token : " + record.Request.Headers.GetValues("Token").FirstOrDefault() + Environment.NewLine);
                }
            }

            if (!string.IsNullOrWhiteSpace(record.Category))
            {
                message.Append("").Append(record.Category);
            }

            //if (!string.IsNullOrWhiteSpace(record.Operator))
            //{
            //    message.Append(" ").Append(record.Operator).Append(" ").Append(record.Operation);
            //}

            //***************************异常日志***********************************//
            if (record.Exception != null && !string.IsNullOrWhiteSpace(record.Exception.GetBaseException().Message))
            {
                var exceptionType = record.Exception.GetType();
                message.Append(Environment.NewLine);
                message.Append("").Append("Error : " + record.Exception.GetBaseException().Message + Environment.NewLine);

            }


            //日志写入本地文件
            Logger[record.Level](Convert.ToString(message) + Environment.NewLine);
        }
    }
}

 创建日志筛选器类LogFilterAttribute，继承于System.Web.Http.Filters下的筛选器特性基类，用于定义日志内容：

using System;
using System.Web.Http;
using System.Web.Http.Controllers;
using System.Web.Http.Tracing;

namespace InsideMesAPI.Log
{
    public class LogFilterAttribute : System.Web.Http.Filters.ActionFilterAttribute
    {
        public override void OnActionExecuting(HttpActionContext actionContext)
        {
            GlobalConfiguration.Configuration.Services.Replace(typeof(ITraceWriter), new AppLog());
            var trace = GlobalConfiguration.Configuration.Services.GetTraceWriter();
            //trace.Info(actionContext.Request, "Controller : " + actionContext.ControllerContext.ControllerDescriptor.ControllerType.FullName + Environment.NewLine + "Action : " + actionContext.ActionDescriptor.ActionName, "JSON", actionContext.ActionArguments);
            //base.OnActionExecuting(actionContext);
        }
    }
}

创建异常筛选器类AbnormalFilterAttribute，继承于System.Web.Http.Filters下的异常筛选器类，用于异常信息的跟踪筛选：

using System;
using System.ComponentModel.DataAnnotations;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Filters;
using System.Web.Http.Tracing;


namespace InsideMesAPI.Log
{
    public class AbnormalFilterAttribute : System.Web.Http.Filters.ExceptionFilterAttribute
    {
        public override void OnException(HttpActionExecutedContext actionExecutedContext)
        {
            GlobalConfiguration.Configuration.Services.Replace(typeof(ITraceWriter), new AppLog());
            var trace = GlobalConfiguration.Configuration.Services.GetTraceWriter();
            trace.Error(actionExecutedContext.Request, "Controller : " + actionExecutedContext.ActionContext.ControllerContext.ControllerDescriptor.ControllerType.FullName + Environment.NewLine + "Action : " + actionExecutedContext.ActionContext.ActionDescriptor.ActionName, actionExecutedContext.Exception);
            var exceptionType = actionExecutedContext.Exception.GetType();
            if (exceptionType == typeof(ValidationException))
            {
                var resp = new HttpResponseMessage(HttpStatusCode.BadRequest) { Content = new StringContent(actionExecutedContext.Exception.Message), ReasonPhrase = "ValidationException" };
                throw new HttpResponseException(resp);
            }
            else if (exceptionType == typeof(UnauthorizedAccessException))
            {
                throw new HttpResponseException(actionExecutedContext.Request.CreateResponse(HttpStatusCode.Unauthorized));
            }
            else
            {
                throw new HttpResponseException(actionExecutedContext.Request.CreateResponse(HttpStatusCode.InternalServerError));
            }
            //base.OnException(actionExecutedContext);
        }
    }
}

4、应用配置

 public static class WebApiConfig
    {
        public static void Register(HttpConfiguration config)
        {
            日志配置
            config.Filters.Add(new Log.LogFilterAttribute());
            config.Filters.Add(new Log.AbnormalFilterAttribute());
         }
     }