AspNet Core 5.0并注册自定义NLog LayoutRenderer

Question

我在 ASP Net Core 5.0 应用程序中使用 NLog.Web.AspNetCore 4.10.0。我创建了一个简单的自定义 ResultLayoutRenderer （为简单起见缩短）：

[LayoutRenderer("result-payload")]
public class ResultLayoutRenderer : AspNetLayoutRendererBase
{
    protected override void DoAppend(StringBuilder builder, LogEventInfo logEvent)
    {
        var httpRequest = HttpContextAccessor?.HttpContext?.Request;
        var result = httpRequest.Headers["Result"];
        builder.Append(result);
    }
}

我的 NLog 配置如下：

<?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">

    <!-- enable asp.net core layout renderers -->
    <extensions>
        <add assembly="NLog.Web.AspNetCore"/>
    </extensions>
    
    <targets>
        <target xsi:type="Null" name="blackhole" />
        <target name="database" xsi:type="Database"
            dbProvider="Npgsql.NpgsqlConnection, Npgsql"
            dbHost="${configsetting:name=NlogConnection.DbHost}"
            dbDatabase="${configsetting:name=NlogConnection.Database}"
            dbUserName="${configsetting:name=NlogConnection.User}"
            dbPassword="${configsetting:name=NlogConnection.Password}"">
            
            <commandText>
                INSERT INTO logs (Application, Logged, Level, Message, Logger, Result) 
                VALUES (@Application, @Logged, @Level, @Message, @Logger, @Result);
            </commandText>
            
            <parameter name="@application" layout="AspNetCoreNlog" />
            <parameter name="@logged" layout="${date}" />
            <parameter name="@level" layout="${level}" />
            <parameter name="@message" layout="${message}" />
            <parameter name="@logger" layout="${logger}" />

            <parameter name="@result" layout="${result-payload}" />
            
        </target>
    </targets>
</nlog>

ResultLayoutRenderer我在以下位置注册Programm.cs：

public static void Main(string[] args)
{
    var logger = NLogBuilder.ConfigureNLog("nlog.config")
        .Setup()
        .SetupExtensions(s => s.RegisterLayoutRenderer<InputDataLayout>("result-payload"))
        .GetCurrentClassLogger();
        ..............
}

但布局不起作用。NLog 内部日志文件包含以下信息：

Error Error parsing layout input-payload will be ignored. Exception: System.ArgumentException: LayoutRenderer cannot be found: 'input-payload'
   at NLog.Config.Factory`2.CreateInstance(String itemName)
   at NLog.Layouts.LayoutParser.GetLayoutRenderer(ConfigurationItemFactory configurationItemFactory, String name, Nullable`1 throwConfigExceptions) 

Answer 1

你们非常接近。NLogBuilder.ConfigureNLog(...)很快就会过时，建议使用流畅的配置 api：

var logger = NLog.LogFactory.Setup()
    .SetupExtensions(ext =>
          ext.RegisterLayoutRenderer<ResultLayoutRenderer>("result-payload")
    )
    .LoadConfigurationFromAppSettings()
    .GetCurrentClassLogger();

另请参阅： https: //github.com/NLog/NLog.Web/blob/master/examples/ASP.NET%20Core%205/ASP.NET%20Core%205%20NLog%20Example/Program.cs