如何在NET 6.0使用结构化的日志系统

          在我们的系统里面，有一项技术是必须使用的，那就是日志记录。我们在调试系统或者跟踪系统运行情况，都可以通过日志了解具体的情况。在项目开发中，我们有可能使用系统本身所带的日志系统，也有可能使用第三方日志框架来记录日志，首先一般基础的内置日志记录器在第三方日志框架中都有实现，然后很多第三方日志框架在功能上更强大和丰富，能满足我们更多的项目分析和诊断的需求。常用的有log4net,更复杂的ELK，项目中有用到Exceptionless。下面说的是Serilog：

　　首先建个AspNetCoreWebAPI6.0的项目，当然也可以是AspNetCore Web MVC项目。

安装组件：Serilog.AspNetCore（6.0.1）和Serilog.Sinks.Seq（5.2.1）

Seq — centralized structured logs for .NET, Java, Node.js (datalust.co)

运行结果如下，已替换系统自带information：

 1 using Serilog;
 2 using Serilog.Events;
 3
 4 // Setup serilog in a two-step process. First, we configure basic logging
 5 // to be able to log errors during ASP.NET Core startup. Later, we read
 6 // log settings from appsettings.json. Read more at
 7 // https://github.com/serilog/serilog-aspnetcore#two-stage-initialization.
 8 // General information about serilog can be found at
 9 // https://serilog.net/
10 Log.Logger = new LoggerConfiguration()
11             .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
12             .Enrich.FromLogContext()
13             .WriteTo.Console()
14             .CreateBootstrapLogger();
15
16 try
17 {
18     Log.Information("Starting the web host");
19     var builder = WebApplication.CreateBuilder(args);
20     // Full setup of serilog. We read log settings from appsettings.json
21     builder.Host.UseSerilog((context, services, configuration) => configuration
22         .ReadFrom.Configuration(context.Configuration)
23         .ReadFrom.Services(services)
24         .Enrich.FromLogContext());
25     // Add services to the container.
26
27     builder.Services.AddControllers();
28     // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
29     builder.Services.AddEndpointsApiExplorer();
30     builder.Services.AddSwaggerGen();
31
32     var app = builder.Build();
33
34     // Configure the HTTP request pipeline.
35     app.UseSerilogRequestLogging(configure =>
36     {
37         configure.MessageTemplate = "HTTP {RequestMethod} {RequestPath} ({UserId}) responded {StatusCode} in {Elapsed:0.0000}ms";
38     });
39     // Configure the HTTP request pipeline.
40     if (app.Environment.IsDevelopment())
41     {
42         app.UseSwagger();
43         app.UseSwaggerUI();
44     }
45
46     app.UseHttpsRedirection();
47
48     app.UseAuthorization();
49
50     app.MapControllers();
51
52     app.Run();
53 }
54 catch
55 (Exception ex)
56 {
57     Log.Fatal(ex, "Host terminated unexpexctedly");
58 }
59 finally
60 {
61     Log.CloseAndFlush();
62 }

 1 {
 2   //"Logging": {
 3   //  "LogLevel": {
 4   //    "Default": "Information",
 5   //    "Microsoft.AspNetCore": "Warning"
 6   //  }
 7   //},
 8   "Serilog": {
 9     "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File", "Serilog.Sinks.Seq" ],
10     "MinimumLevel": "Information",
11     // Where do we want to write our logs to? Choose from a large number of sinks:
12     // https://github.com/serilog/serilog/wiki/Provided-Sinks.
13     "WriteTo": [
14       {
15         "Name": "Console"
16       },
17       {
18         "Name": "File",
19         "Args": { "path": "Logs/log.txt" }
20       },
21       {
22         "Name": "Seq",
23         "Args": { "serverUrl": "http://localhost:8888" }
24       }
25     ],
26     "Enrich": [ "FromLogContext", "WithMachineName", "WithThreadId" ],
27     "Properties": {
28       "Application": "AspNetCoreSerilogDemo"
29     }
30   },
31   "AllowedHosts": "*"
32 }

请求跟踪分析：

using Microsoft.AspNetCore.Mvc;

namespace AspNetCoreSerilogDemo.Controllers
{
    [ApiController]
    [Route("[controller]")]
    public class SeriLogDemoController : ControllerBase
    {

        private readonly ILogger<SeriLogDemoController> _logger;

        public SeriLogDemoController(ILogger<SeriLogDemoController> logger)
        {
            _logger = logger;
        }

        [HttpGet]
        public string String()
        {
            _logger.LogInformation("this is serilog...");
            return "Suscess";
        }

    }
}

配置文件里面输出路径有"Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File", "Serilog.Sinks.Seq" ],所以同样会输出到日志文件中,指定路径和文件名：

更多更详细功能参考:

Serilog — simple .NET logging with fully-structured events

Seq — centralized structured logs for .NET, Java, Node.js (datalust.co)