Event log in in worker service not published to Azure Application Insight

Question

I am building a Worker Service as Windows Service. I use EventLog for logging. I also want to add ApplicationInsights to log the events. I follow this article https://learn.microsoft.com/en-us/azure/azure-monitor/app/worker-service , install the SDK using Nuget and setup everything as requested. Here is my program.cs configuration.

public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)                
            .ConfigureServices((hostContext, services) =>
            {
                services.AddHostedService<Worker>();
                services.AddApplicationInsightsTelemetryWorkerService();
                services.CustomeDependencyInjection();
            })
            .UseWindowsService()
            .ConfigureLogging(logging =>
            {
                logging.AddEventLog(eventLogSetting =>
                {
                    eventLogSetting.LogName = "MyTestEventLog";
                    eventLogSetting.SourceName = "MyTestEventApp";
                });
            });

Here is the appsetting.json file

{
  "ApplicationInsights": {
      "InstrumentationKey": "bd******-****-****-****-***********b"
  },
  Logging": {
    "LogLevel": {
    "Default": "Information",
    "Microsoft": "Information",
    "Microsoft.Hosting.Lifetime": "Information"
    },
    "EventLog": {
      "LogLevel": {
      "Default": "Information",
      "Microsoft": "Information",
      "Microsoft.Hosting.Lifetime": "Information"
      }
    }
  }
}

Here is an logging example in the worker.cs file

public Worker(ILogger<Worker> logger, TelemetryClient tc)
{
        _logger = logger;
        this.tc = tc;
 }
 public Task StartAsync(CancellationToken cancellationToken)
 {
        this._logger.LogInformation("In Start");
        using (tc.StartOperation<RequestTelemetry>("Operation"))
        {
            /** 
                my service starting code 
            **/
            this._logger.LogInformation("Service is being started");
            tc.TrackEvent("Worker service starting operation completed.");
        }
        this._logger.LogInformation( "Service Started");
        return Task.CompletedTask;
 }

When I run the application, I can see a customEvent. I can also see request event. But I cannot find anything in the trace where I was expecting the info sent using _logger. I checked the output window and also did not find any telemetry is sent against the _logger.LogInformation.

What am I doing wrong in here and how can I make the Logger Info available to the ApplicationInsights? Or am I not looking into the right place?

Answer 1

Application Insight defaults to Warning as the log level. Since you are tracing with level Information you need to configure application insights using the appsettings.json file:

{
  "ApplicationInsights": {
      "InstrumentationKey": "bd******-****-****-****-***********b"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Information",
      "Microsoft.Hosting.Lifetime": "Information"
    },
    "ApplicationInsights": {
      "LogLevel": {
        "Default": "Information"
      }
    }
    "EventLog": {
        "LogLevel": {
        "Default": "Information",
        "Microsoft": "Information",
        "Microsoft.Hosting.Lifetime": "Information"
      }
    }
  }
}