将 CloudWatch 配置为 NLog 的目标

Question

I have been trying to set cloudwatch as a target to my Nlog framework in .Net application. They haven't mentioned much on their documentation about this.

This is my Nlog.config file

<?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"
  throwExceptions="true">
<targets>
  <target name="aws" type="AWSTarget" logGroup="NLog.ConfigExample" region="us-east-1"/>
  <target name="logfile" xsi:type="Console" layout="${callsite} ${message}"/>
</targets>
<rules>
   <logger name="*" minlevel="Info" writeTo="logfile,aws" />
</rules
</nlog>

Nothing major just as their sample project says. I have already set AWS credentials in my environment variables.

I have already created a logGroup in cloud watch as well

Answer 1

This works for me for a .NET Core application.

using Microsoft.Extensions.Options;
using NLog;
using NLog.AWS.Logger;
using NLog.Config;
using NLog.Layouts;
using System;

namespace AAAA.BBBB.CCCC
{
    public interface ILogger
    {
        void LogError(string message);
        void LogError(string message, Exception exception);
        void LogInformation(string message);
    }

    public class Logger : ILogger
    {
        private static readonly NLog.Logger _logger = LogManager.GetCurrentClassLogger();

        public Logger(IOptions<AppSettings> appSettings)
        {
            var awsSettings = appSettings.Value.AwsSettings;

            var awsTarget = new AWSTarget()
            {
                LogGroup = awsSettings.CloudWatchLogGroup,
                Region = awsSettings.Region,
                Credentials = new Amazon.Runtime.BasicAWSCredentials(awsSettings.AccessId, awsSettings.AccessKey),
                Layout = new SimpleLayout
                {
                    Text = "${longdate} ${level:uppercase=true} ${machinename} ${message} ${exception:format=tostring}"
                }
            };

            var config = new LoggingConfiguration();
            config.AddTarget("aws", awsTarget);
            config.LoggingRules.Add(new LoggingRule("*", LogLevel.Debug, awsTarget));
            LogManager.Configuration = config;
        }

        public void LogError(string message)
        {
            _logger.Error(message);
        }

        public void LogError(string message, Exception exception)
        {
            _logger.Error(exception, message);
        }

        public void LogInformation(string message)
        {
            _logger.Info(message);
        }
    }

    public class AppSettings
    {
        public AwsSettings AwsSettings { get; set; }
    }

    public class AwsSettings
    {
        public string AccessId { get; set; } = default!;
        public string AccessKey { get; set; } = default!;
        public string CloudWatchLogGroup { get; set; } = default!;
        public string Region { get; set; } = default!;
    }
}

Answer 2

What if you include <extensions> ?

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      throwConfigExceptions="true">
  <extensions>
    <add assembly="NLog.AWS.Logger" />
  </extensions>
  <targets>
    <target name="aws" type="AWSTarget" logGroup="NLog" region="us-east-1"/>
    <target name="logfile" xsi:type="Console" layout="${callsite} ${message}" />
  </targets>
  <rules>
    <logger name="*" minlevel="Info" writeTo="logfile,aws" />
  </rules>
</nlog>