netcore3.1 使用Nlog 将本地日志写入到elk

• 新建webapi
• 添加Nlog nuget包引用
• 添加Nlog配置文件

  <?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"
        autoReload="true"
        internalLogLevel="Warn"
        internalLogFile="internal-nlog.txt">
  
    <extensions>
      <!--enable NLog.Web for ASP.NET Core-->
      <add assembly="NLog.Web.AspNetCore"/>
    </extensions>
  
    <!-- define various log targets -->
    <!--定义日志文件目录-->
    <variable name="logDirectory" value="${basedir}/logs/${shortdate}"/>
    <variable name="nodeName" value="node1"/>
  
    <targets async="true">
      <!-- 全部日志target -->
      <target xsi:type="File"
              name="allfile"
              fileName="${logDirectory}/nlog-all/${shortdate}.log"
              layout="#node1#${longdate}#${logger}#${uppercase:${level}}#${callsite}#${callsite-linenumber}#${aspnet-request-url}#${aspnet-request-method}#${aspnet-mvc-controller}#${aspnet-mvc-action}#${message}#${exception:format=ToString}#"
              keepFileOpen="false"
              />
  
      <!-- 本地文件日志target -->
      <target xsi:type="File"
              name="ownLog-file"
              fileName="${logDirectory}/nlog-${level}/${shortdate}.log"
              layout="#${longdate}#${nodeName}#${logger}#${uppercase:${level}}#${callsite}#${callsite-linenumber}#${aspnet-request-url}#${aspnet-request-method}#${aspnet-mvc-controller}#${aspnet-mvc-action}#${message}#${exception:format=ToString}#"
              keepFileOpen="false"
              />
  
      <!-- Tcp日志target -->
      <target xsi:type="Network"
              name="ownLog-tcp"
              keepConnection="false"
              address ="tcp://192.168.3.10:5000"
              layout="#${longdate}#${nodeName}#${logger}#${uppercase:${level}}#${callsite}#${callsite-linenumber}#${aspnet-request-url}#${aspnet-request-method}#${aspnet-mvc-controller}#${aspnet-mvc-action}#${message}#${exception:format=ToString}#"
              />
      <!--grok 规则-->
      <!--%#{DATA:request_time}#%{DATA:node_name}#%{DATA:class_name}#%{DATA:log_level}#%{DATA:call_site}#%{DATA:line_number}#%{DATA:request_url}#%{DATA:request_method}#%{DATA:container_name}#%{DATA:action_name}#%{DATA:log_info}#%{DATA:exception_msg}#-->
      <!--空白-->
      <target xsi:type="Null" name="blackhole" />
    </targets>
  
    <!--日志级别 Trace -》Debug-》 Info -》Warn-》 Error-》 Fatal-->
    <!--日志规则-->
    <rules>
      <!--全部日志, 包括Microsoft日志-->
      <logger name="*" minlevel="Trace" writeTo="allfile" />
  
      <!--自定义日志，排除Microsoft日志-->
      <logger name="Microsoft.*" minlevel="Trace" writeTo="blackhole" final="true" />
      <logger name="*" minlevel="Debug" writeTo="ownLog-file" />
      <logger name="*" minlevel="Info" writeTo="ownLog-tcp" />
    </rules>
  </nlog>

• startup添加中间件

  using Microsoft.AspNetCore.Builder;
  using Microsoft.AspNetCore.Hosting;
  using Microsoft.Extensions.Configuration;
  using Microsoft.Extensions.DependencyInjection;
  using Microsoft.Extensions.Hosting;
  using Microsoft.Extensions.Logging;
  using NLog;
  using NLog.Extensions.Logging;
  using NLog.Web;namespace UserWebApplication
  {
      public class Startup
      {
  
          public Startup(IConfiguration configuration)
          {
              Configuration = configuration;
          }
  
          public IConfiguration Configuration { get; }
  
          // This method gets called by the runtime. Use this method to add services to the container.
          public void ConfigureServices(IServiceCollection services)
          {
              var currentClassLogger = NLogBuilder.ConfigureNLog("nlog.config").GetCurrentClassLogger();
              services.AddSingleton(currentClassLogger);
              services.AddControllers();
            
          }
  
          // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
          public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory, IHostApplicationLifetime lifetime)
          {
              //loggerFactory.AddNLog();
              //loggerFactory.ConfigureNLog("nlog.config");
              if (env.IsDevelopment())
              {
                  app.UseDeveloperExceptionPage();
              }
  
              app.UseRouting();
  
              app.UseAuthorization();
  
              //停止时注销
              lifetime.ApplicationStopped.Register(() =>
              {
                  //Nlog 确保在应用程序退出之前刷新并停止内部计时器/线程（避免Linux上出现分段错误）
                  LogManager.Shutdown();
              });
  
              app.UseEndpoints(endpoints =>
              {
                  endpoints.MapControllers();
              });
          }
      }
  }

• Program 添加Loggin配置

  using Microsoft.AspNetCore.Hosting;
  using Microsoft.Extensions.Hosting;
  using Microsoft.Extensions.Logging;
  using NLog.Web;
  
  namespace UserWebApplication
  {
      public class Program
      {
          public static void Main(string[] args)
          {
              CreateHostBuilder(args).Build().Run();
          }
  
          public static IHostBuilder CreateHostBuilder(string[] args) =>
              Host.CreateDefaultBuilder(args)
                  .ConfigureWebHostDefaults(webBuilder =>
                  {
                      webBuilder.UseStartup<Startup>();
                  }).ConfigureLogging(logging =>
                  {
                      logging.ClearProviders();
                      logging.SetMinimumLevel(Microsoft.Extensions.Logging.LogLevel.Trace);
                  }).UseNLog();
      }
  }

• 修改appsetting.json 配置

  {
    "Logging": {
      "IncludeScopes": false,
      "LogLevel": {
        "Default": "Trace",
        "Microsoft": "Warning",
        "Microsoft.Hosting.Lifetime": "Information"
      }
    },
    "AllowedHosts": "*"
  }

• 使用示例

    private readonly ILogger<WeatherForecastController> _logger;
  
          public WeatherForecastController(ILogger<WeatherForecastController> logger)
          {
              _logger = logger;
          }
  
          [HttpGet]
          public IEnumerable<WeatherForecast> Get()
          {
              var rng = new Random();
              _logger.LogInformation("这是一条测试消息Information");
  
              _logger.LogError("这是一条测试消息Erro");
  
              _logger.LogDebug("这是一条测试消息Debug");
  
              return Enumerable.Range(1, 5).Select(index => new WeatherForecast
              {
                  Date = DateTime.Now.AddDays(index),
                  TemperatureC = rng.Next(-20, 55),
                  Summary = Summaries[rng.Next(Summaries.Length)]
              })
              .ToArray();
          }

   参考自https://github.com/NLog/NLog/wiki/Getting-started-with-ASP.NET-Core-2