NLog 2 files logging will log same info in both files-CodePudding

So I have a rather simple problem, but seems like I am missing something. I have a WPF application ( .NET Core 5.0 ).

I am trying to use 2 files for logging, but whenever I retrieve one logger and write a message, I get the same log in both files.

Here is my code.

        private void SetupLogger()
        {
            // Step 1. Create configuration object 
            var config = new LoggingConfiguration();

            // Step 2. Create targets
            var firstTarget = new FileTarget()
            {
                Name = "FirstLogger",
                FileName = Path.Combine(basePath, "log1.txt"),
                Layout = "${longdate} ${level} ${message}  ${exception}"
            };

            var secondTarget = new FileTarget()
            {
                Name = "SecondLogger",
                FileName = Path.Combine(basePath, "log2.txt"),
                Layout = "${longdate} ${level} ${message}"
            };
            config.AddTarget("FirstLogger", firstTarget );
            config.AddTarget("SecondLogger", secondTarget );


            var ruleInfo1 = new LoggingRule("*", NLog.LogLevel.Trace, firstTarget );
            var ruleInfo2= new LoggingRule("*", NLog.LogLevel.Trace, secondTarget );

            // Step 3. Define rules
            config.LoggingRules.Add(ruleInfo1); 
            config.LoggingRules.Add(ruleInfo2); 

            // Step 4. Activate the configuration
            LogManager.Configuration = config;

            // Example usage
            var logger = LogManager.GetLogger("FirstLogger");
            logger.Info("App starting...");
        }

In an other file I have a second log

        public void Start()
        {
            //initialize app
            var logger = LogManager.GetLogger("FirstLogger");
            logger.Info("App finished initializing...");
        }

Now what I see both logs in both files.

LE: I've tried this and it still logs to both files.

  var ruleInfo1 = new LoggingRule("FirstLogger", LogLevel.Trace, firstTarget )
            {
                Final = true
            };           
            var ruleInfo2 = new LoggingRule("*", LogLevel.Trace, secondTarget );

  config.LoggingRules.Add(ruleInfo1); 
            config.LoggingRules.Add(ruleInfo2);

CodePudding user response：

That's correct.

The only difference between the two loggers is an exception.

You're not throwing any exceptions, and thus none will be logged.

CodePudding user response：

Logging-rules with wildcard * for the Logger-name will match all loggers:

// Step 3. Define rules
var ruleInfo1 = new LoggingRule("*", NLog.LogLevel.Trace, firstTarget );
config.LoggingRules.Add(ruleInfo1);
var ruleInfo2 = new LoggingRule("*", NLog.LogLevel.Trace, secondTarget );
config.LoggingRules.Add(ruleInfo2);

Maybe change into this:

// Step 3. Define rules
var ruleErrors = new LoggingRule("*", NLog.LogLevel.Warn, firstTarget );
config.LoggingRules.Add(ruleErrors);
var ruleUsers = new LoggingRule("UserLog", NLog.LogLevel.Trace, firstTarget );
config.LoggingRules.Add(ruleUsers);
var ruleAll = new LoggingRule("*", NLog.LogLevel.Trace, secondTarget );
config.LoggingRules.Add(ruleAll);

Now the 3 rules will ensure:

ruleErrors - Will redirect warnings/errors into firstTarget (Filter on LogLevel)
ruleUsers - Will redirect events written to LogManager.GetLogger("UserLog") into firstTarget (Filter on Logger-name)
ruleAll - Will redirect all events to secondTarget (Without any filter)