ASP.NET Core 8 轻松配置Serilog日志

与许多其他 .NET 库一样，Serilog 提供了将诊断日志输出到文件、控制台以及其他位置的功能。它易于设置，拥有简洁的 API，并且可以在最新的 .NET 平台之间进行移植。

官方网站：Serilog — simple .NET logging with fully-structured events

1、安装Serilog

dotnet add package Serilog.AspNetCore

2、将Serilog配置信息添加到appsettings.json

在ASP .NET Core后端服务开发中，任何可配置的项我们都应该配置在appsettings.json文件中。

相关配置信息可查看网站：https://github.com/serilog/serilog-settings-configuration

"Serilog": {
    "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File" ],
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Microsoft": "Warning",
        "System": "Warning"
      }
    },
    "WriteTo": [
      {
        "Name": "Console"
      },
      {
        "Name": "File",
        "Args": {
          "path": "logs\\log.txt",
          "rollingInterval": "Day"
        }
      }
    ],
    "Enrich": [ "FromLogContext", "WithMachineName", "WithThreadId" ]
  }

3、在Program.cs 文件中使用两阶段初始化方式配置Serilog

为了完全捕获程序启动过程中和启动完成后，所有异常日志信息。

第一步：CreateBootstrapLogger()

程序启动时会立即配置一个初始的“引导（bootstrap）”日志记录器，来记录程序启动过程中发生的异常日志。

Log.Logger = new LoggerConfiguration()
.MinimumLevel.Override("Microsoft", LogEventLevel.Information)
.Enrich.FromLogContext()
.WriteTo.Console()
.WriteTo.File("logs\\log.txt", rollingInterval: RollingInterval.Day)
.CreateBootstrapLogger();

第二步：AddSerilog()

当程序加载完成后，使用appsettings.json文件中Serilog配置来替换引导日志记录器。

builder.Services.AddSerilog((services, lc) => 
lc.ReadFrom.Configuration(builder.Configuration));

4、添加Serilog请求日志记录中间件

app.UseSerilogRequestLogging();

5、完整代码

appsetting.json

{
  "Serilog": {
    "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File" ],
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Microsoft": "Warning",
        "System": "Warning"
      }
    },
    "WriteTo": [
      {
        "Name": "Console"
      },
      {
        "Name": "File",
        "Args": {
          "path": "logs\\log.txt",
          "rollingInterval": "Day"
        }
      }
    ],
    "Enrich": [ "FromLogContext", "WithMachineName", "WithThreadId" ]
  }
}

Program.cs

using Serilog;
using Serilog.Events;

namespace Common.Backend.WebApi
{
    public class Program
    {
        public static void Main(string[] args)
        {
            Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
            .Enrich.FromLogContext()
            .WriteTo.Console()
            .WriteTo.File("logs\\log.txt", rollingInterval: RollingInterval.Day)
            .CreateBootstrapLogger();

            try
            {
                var builder = WebApplication.CreateBuilder(args);

                builder.Services.AddSerilog((services, lc) => lc.ReadFrom.Configuration(builder.Configuration));

                var app = builder.Build();

                app.UseSerilogRequestLogging();

                app.Run();
            }
            catch(Exception ex)
            {
                Log.Fatal(ex, "Application terminated unexpectedly");
            }
            finally
            {
                Log.CloseAndFlush();
            }
        }
    }
}