RavenDb NLog配置冲突

Question

我想使用NLog登录到RavenDb数据库。显然没有现有的NLog目标(根据this和搜索)，所以我正在尝试编写我自己的。我总是与RavenDb客户端自己的NLog配置发生冲突，并且我不知道如何解决这个问题。这是我的目标：

namespace NLog.RavenDb
{
    class LogEntry
    {
        public string Id { get; set; }
        public Exception Exception { get; set; }
        public string LogLevel { get; set; }
        public StackTrace StackTrace { get; set; }
        public DateTimeOffset TimeStamp { get; set; }
        public string Message { get; set; }
    }

    public class RavenDbTarget : NLog.Targets.TargetWithLayout
    {
        public static IDocumentStore Store { get; set; }

        protected override void Write(LogEventInfo logEvent)
        {
            if (Store == null)
            {
                const string noStoreWarning = "No Document Store set for the RavenDb Log target";
                Debug.WriteLine(noStoreWarning);
                return;
            }

            LogEntry entry = new LogEntry
            {
                Exception = logEvent.Exception,
                LogLevel = logEvent.Level.Name,
                Message = logEvent.FormattedMessage,
                StackTrace = logEvent.StackTrace,
                TimeStamp = new DateTimeOffset(logEvent.TimeStamp)
            };

            using (var session = Store.OpenSession())
            {
                session.Store(entry);
                session.SaveChanges();
            }
        }
    }
}

下面是如何让它与SimpleConfigurator一起工作的方法：

RavenDbTarget.Store = new DocumentStore { Url = "http://localhost:8080/" };
RavenDbTarget.Store.Initialize();

NLog.Config.SimpleConfigurator.ConfigureForTargetLogging(new RavenDbTarget());
Logger logger = NLog.LogManager.GetLogger("Any");
logger.Info("Hi");

但是，RavenDb也使用NLog.config，所以当我在其中放入对我的目标的引用时，它会在Store.Initialize()抛出一个异常。下面是我在NLog.config中尝试的方法(NLog.RavenDb是包含RavenDb目标的库项目的名称)：

<?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">

    <extensions>
        <add assembly="Nlog.RavenDb"/>
    </extensions>

    <targets>
        <target xsi:type="NLog.RavenDb.RavenDbTarget" name="Raven"/>
        <target xsi:type="File" name="f" fileName="${basedir}/logs/${shortdate}.log"
                layout="${longdate} ${uppercase:${level}} ${message}" />
    </targets>

    <rules>
        <logger minlevel="Trace" name="Any" writeTo="Raven" />
    </rules>
</nlog>

我怎样才能让我的NLog.config文件和RavenDb的使用更好呢？

Answer 1

找到了。我遗漏了目标类上的目标属性，如here所示。

[NLog.Targets.Target("RavenDb")]
public class RavenDbTarget : NLog.Targets.TargetWithLayout

传递给Target属性的name参数是您在配置文件中引用为"type“的参数：

<?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">

    <extensions>
        <add assembly="Nlog.RavenDb"/>
    </extensions>

    <targets>
        <target xsi:type="RavenDb" name="Raven"/>
    </targets>

    <rules>
        <logger minlevel="Trace" name="Any" writeTo="Raven" />
    </rules>
</nlog>

现在NLog会自动拾取NLog.config，我不需要任何额外的配置代码。下面是我的测试控制台应用程序的main方法的内容：

        RavenDbTarget.Store = new DocumentStore { Url = "http://localhost:8080/" };
        RavenDbTarget.Store.Initialize();

        Logger logger = LogManager.GetLogger("Any");
        logger.Info("Hi");