ASP.NET 404请求作为警告

Question

如果我用ASP.NET Core Web App (Model-View-Controller)创建了一个新的dotnet new mvc，那么它已经配置好了日志记录。

但是，http请求错误代码被记录为info事件。

info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
      Request starting HTTP/1.1 GET https://localhost:5001/doesnotexists
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
      Request finished in 4.4052ms 404

是否可以通过调查和重写日志事件将此行为更改为(4xx ->警告、5xx ->错误) .i.e。

我已经看过https://learn.microsoft.com/en-us/aspnet/core/fundamentals/logging/?view=aspnetcore-2.2了

这看上去乱七八糟的，但我没有找到一个钩子来达到这个目的

    var webHost = new WebHostBuilder()
        .UseKestrel()
        .UseContentRoot(Directory.GetCurrentDirectory())
        .ConfigureLogging((hostingContext, logging) =>
        {
            // investigate and rewrite log event
        })
        .UseStartup<Startup>()
        .Build()

Answer 1

您需要实现自己的ILogger和ILoggerProvider。

一个简单的演示，如：

1. CustomLogger 公共类CustomLogger : ILogger { public CustomLogger() {} public IDisposable BeginScope(TState state)=> NullScope.Instance；public bool IsEnabled(LogLevel logLevel) => true；公共无效日志( logLevel logLevel、eventId EventId、TState状态、异常、Func格式化程序){ var msg =格式化程序(状态、异常)；if (msg.Contains("404")) { LogLevel = LogLevel.Warning；} Console.WriteLine($"{ GetLogLevelString(logLevel) }：{ eventId }{ msg }{ exception }")；}私有静态字符串GetLogLevelString(LogLevel logLevel) { switch (logLevel) { case LogLevel.Trace:返回"trce"；案例LogLevel.Debug:返回"dbug"；LogLevel.Information:返回"info"；LogLevel.Warning:返回“警告”；case LogLevel.Error:返回"fail"；case LogLevel.Critical:返回"crit"；默认情况:抛出新的LogLevel.Critical}}
2. CustomLoggerProvider 公共类CustomLoggerProvider : ILoggerProvider { public ILogger CreateLogger(string categoryName) {返回新的CustomLogger()；} public void (){}
3. 注册以上代码公共静态IWebHostBuilder CreateWebHostBuilder(string[] args) => WebHost.CreateDefaultBuilder(args) .UseStartup() .ConfigureLogging(config => { config.ClearProviders()；config.AddProvider(新CustomLoggerProvider())；})； 您可以检查日志记录并实现您自己的日志提供程序。

Answer 2

单线解

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

using Microsoft.Extensions.Logging;

namespace temp
{
    public class Startup
    {    
        public void Configure(IApplicationBuilder app, IHostEnvironment env, ILogger<Startup> logger)
        {

            ...

            app.UseStatusCodePages(async context =>
            {
                var code = context.HttpContext.Response.StatusCode;
                if (code == 404) {
                    logger.Log(LogLevel.Error, null, "log message");
                }
            });

            ...

        }
    }
}