ASP.NET MVC 与NLog的使用

NLog是一个.NET 下一个完善的日志工具，个人已经在项目中使用很久，与ELMAH相比，可能EAMAH更侧重 APS.NET MVC 包括调试路由，性能等方面，而NLog则更简洁。

github: https://github.com/NLog/NLog
web: http://nlog-project.org
logview：http://www.gibraltarsoftware.com/loupe/extensions/nlog
http://stackoverflow.com/questions/710863/log4net-vs-nlog
http://stackoverflow.com/questions/4091606/most-useful-nlog-configurations

Supported targets include:
    Files - single file or multiple, with automatic file naming and archival
    Event Log - local or remote
    Database - store your logs in databases supported by .NET
    Network - using TCP, UDP, SOAP, MSMQ protocols
    Command-line console - including color coding of messages
    E-mail - you can receive emails whenever application errors occur
    ASP.NET trace
    ... and many more

Other key features:
    very easy to configure, both through configuration file and programmatically
    easy-to-use logger pattern known from log4xxx
    advanced routing using buffering, asynchronous logging, load balancing, failover, and more
    cross-platform support: .NET Framework, .NET Compact Framework and Mono (on Windows and Unix)

安装

配置

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

  <!-- 
  See http://nlog-project.org/wiki/Configuration_file 
  for information on customizing logging rules and outputs.
   -->

  <!-- 使用说明
                1.一般控制台调式日志(打印到控制台)
                logger.Trace("GetHotelBrand 操作数据库异常 sqlText : " + sqlText);
                2. 一般文本日志，如记录接口，响应值等 请求参数等(记录文本,支持异步)，
                  logger.Info("GetHotelBrand 操作数据库异常 sqlText : " + sqlText);
                3.错误日志  一般影响到业务流程的正常使用 (记录到DB)
                logger.ErrorException("GetHotelBrand 操作数据库异常 sqlText : " + sqlText, ex);
                4.致命性错误  如金额数据，订单数据操作失败  (发送邮件通知)
                logger.FatalException("GetHotelBrand 操作数据库异常 sqlText : " + sqlText, ex);
  -->
  
  <targets>
    <!-- add your targets here -->
    <!--调式打印控制台日志-->
    <target name="console" xsi:type="ColoredConsole" layout="[${date:format=yyyy-MM-dd HH:mm:ss}][${level}] ${message} ${exception}"/>

    <!-- 记录一般INFO文本日志(启用异步) -->
    <target name="file" xsi:type="AsyncWrapper" queueLimit="5000" overflowAction="Discard">
      <target xsi:type="File" fileName="${basedir}/logs/${shortdate}/${level}.log"  layout="${longdate} ${uppercase:${level}} ${message}"  maxArchiveFiles="100" />
    </target>
    
    <!-- 发生错误异常记录数据库日志 -->
    <target name="database" xsi:type="Database"  useTransactions="true" connectionString="Data Source=xxxxxxxx;Initial Catalog=Log;Persist Security Info=True;User ID=sa;Password=123456"  commandText="insert into NLogException_HomeinnsInterface([CreateOn],[Origin],[LogLevel], [Message], [Exception],[StackTrace]) values (getdate(), @origin, @logLevel, @message,@exception, @stackTrace);">
      <!--日志来源-->
      <parameter name="@origin" layout="${callsite}"/>
      <!--日志等级-->
      <parameter name="@logLevel" layout="${level}"/>
      <!--日志消息-->
      <parameter name="@message" layout="${message}"/>
      <!--异常信息-->
      <parameter name="@exception" layout="${exception}" />
      <!--堆栈信息-->
      <parameter name="@stackTrace" layout="${stacktrace}"/>
    </target>

    <!-- 发生致命错误发送邮件日志 -->
    <target name="email" xsi:type="Mail"
               header="-----header------"
               footer="-----footer-----"
               layout="${longdate} ${level} ${callsite} ${message} ${exception:format=Message, Type, ShortType, ToString, Method, StackTrace}"
               html="false"
               encoding="UTF-8"
               addNewLines="true"
               subject="${message}"
               to=""
               from=""
               body="${longdate} ${level} ${callsite} ${message} ${exception:format=Message, Type, ShortType, ToString, Method, StackTrace}"
               smtpUserName=""
               enableSsl="false"
               smtpPassword=""
               smtpAuthentication="Basic"
               smtpServer="smtp.163.com"
               smtpPort="25">
    </target>
  </targets>
  <rules>
    <!-- add your logging rules here -->
    <logger name="*" minlevel="Trace" writeTo="console" />
    <logger name="*" minlevel="Info" writeTo="file" />
    <logger name="*" minlevel="Error" writeTo="database"/>
    <logger name="*" minlevel="Fatal" writeTo="email" />
  </rules>
</nlog>

配置什么的也没有什么好说的，跟相对Log4j配置简洁些，支持 控制台，文件（异步），数据库，Email，够用了，其他的方式还没有研究。

日志查看

这里推荐一款日志查看工具：Loupe ，支持.NET 平台下集成,在Asp.NET MVC 下只需要配置Nuget引用相应的包。

Install-Package Gibraltar.Agent.Web.Mvc

注册拦截器

using Gibraltar.Agent;
    using Gibraltar.Agent.Web.Mvc.Filters;

    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            // Initialize Gibraltar Loupe
            Log.StartSession();
            GlobalConfiguration.Configuration.Filters.Add(new WebApiRequestMonitorAttribute());
            GlobalFilters.Filters.Add(new MvcRequestMonitorAttribute());
            GlobalFilters.Filters.Add(new UnhandledExceptionAttribute());
         }
      }

结合SignalR

今天看到一篇与signalr结合的文章，可以把记录的日志主动推送到浏览器 ： http://www.codeproject.com/Articles/758633/Streaming-logs-with-SignalR  ，原理NLog支持MethodCallTarget特性，发生异常时，可以触发Signalr的相关方法，从而推送错误消息到浏览器。

<configSections>
        <section name="nlog" type="NLog.Config.ConfigSectionHandler, NLog" />
    </configSections>
    <nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" throwExceptions="false">
        <targets>
            <target name="debug" xsi:type="Debugger" layout=" #${longdate} - ${level} - ${callsite} - ${message}" />
            <target name="signalr" xsi:type="MethodCall" className="SignalRTargetHub, App_Code" methodName="Send">
                <parameter layout="${longdate}" />
                <parameter layout="${level}" />
                <parameter layout="${callsite}: ${message}" />
            </target>
        </targets>
        <rules>
            <logger name="*" minlevel="Trace" writeTo="debug" />
            <logger name="*" minlevel="Trace" writeTo="signalr" />
            </rules>
    </nlog>

使用OWIN宿主，Open Web Interface for .NET (OWIN)在Web服务器和Web应用程序之间建立一个抽象层。OWIN将网页应用程序从网页服务器分离出来，然后将应用程序托管于OWIN的程序而离开IIS之外。

public class SignalRTargetHub : Hub
{
    public void Hello()
    {
        this.Clients.Caller.logEvent(
            DateTime.UtcNow.ToLongTimeString(),
            "info",
            "SignalR connected");
    }

    static IHubContext signalRHub;
    public static void Send(string longdate, string logLevel, String message)
    {
        if (signalRHub == null)
        {
            signalRHub = GlobalHost.ConnectionManager.GetHubContext<SignalRTargetHub>();
        }

        if (signalRHub != null)
        {
            signalRHub.Clients.All.logEvent(longdate, logLevel, message);
        }
    }
}

[assembly: OwinStartup(typeof(SignalRStartup))]
public class SignalRStartup
{
    public void Configuration(IAppBuilder app)
    {
        app.MapSignalR();
    }
}

注册Global事件

  Logger logger = NLog.LogManager.GetCurrentClassLogger();
  void Application_Error(object sender, EventArgs e)
    {
        Exception lastException = Server.GetLastError();
        logger.Fatal("Request: '{0}'
 Exception:{1}", HttpContext.Current.Request.Url, lastException);
    }

Refer:
How to NLog (2.1) with VisualStudio 2013
http://www.codeproject.com/Tips/749612/How-to-NLog-with-VisualStudio
Logging: How to Growl with NLog 3
http://www.codeproject.com/Articles/786304/Logging-How-to-Growl-with-NLog-or
Five methods to Logging in MVC 3.0(介绍较详细，需翻墙)
http://www.codeproject.com/Tips/237171/Five-methods-to-Logging-in-MVC
微软最新的Web服务器Katana发布了版本3（OWIN）
http://www.infoq.com/cn/news/2014/08/Katana-3