Azure – Why is ILogger.LogError working but not ILogger.LogInformation?

Why is it that when I inject ILogger<MyClassName> and call Logger.LogInformation I don’t see that in Application Insights, but when I call Logger.LogError I do?

Here is my code

    public async ValueTask DeleteMessageAsync(string chatId, int messageId)
    {
        Logger.LogInformation(
            "Deleting message: {chatId} {messageId}",
            chatId,
            messageId);

        try
        {
            await TelegramBotClient.DeleteMessageAsync(chatId, messageId);
        }
        catch (ApiRequestException ex)
            when (ex.ErrorCode == (int)HttpStatusCode.BadRequest)
        {
            Logger.LogError(ex, "Could not Delete message");
        }
    }

Here is an example of the event showing up in the Live Metrics section of Application Insights.

Here is the result of searching for that InvokationId

I also get zero results when searching for the word "Piff", which is clearly in the live view.

Here is the logging section of my host.json file

  "logging": {
    "applicationInsights": {
      "samplingSettings": {
        "isEnabled": true,
        "excludedTypes": "Request"
      },
      "enableLiveMetricsFilters": true
    },
    "DurableTask.AzureStorage": "Information",
    "DurableTask.Core": "Information",
    "logLevel": {
      "Default": "Information",
      "Microsoft": "Information",
      "Microsoft.Hosting.Lifetime": "Information"
    }
}

Here is the host builder for my Azure functions app

IHost host = new HostBuilder()
    .AddServiceDefaults(useOtlpExporter: false, isDevelopment: true)
    .ConfigureFunctionsWorkerDefaults()
    .ConfigureServices(services =>
    {
        services.AddApplicationInsightsTelemetryWorkerService();
        services.ConfigureFunctionsApplicationInsights();
        services.AddSingleton<ITelegramBroadcastService, TelegramBroadcastService>();
        services.AddSingleton<IAuthorizationService, AuthorizationService>();
        services.AddDurableTaskClient(x =>
        {
        });
        services.AddAzureClients(clientBuilder =>
        {
            clientBuilder.AddBlobServiceClient(Environment.GetEnvironmentVariable("AzureWebJobsStorage"));
        });
    })
    .ConfigureAppConfiguration((context, config) =>
    {
        if (context.HostingEnvironment.IsDevelopment())
            config.AddUserSecrets<Program>();
    })
    .Build();

host.Run();

The AddServiceDefaults extension is the one added by default in a new Aspire app.

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Diagnostics.HealthChecks;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Diagnostics.HealthChecks;
using Microsoft.Extensions.Logging;
using OpenTelemetry.Logs;
using OpenTelemetry.Metrics;
using OpenTelemetry.Trace;

namespace Microsoft.Extensions.Hosting;

public static class Extensions
{
    public static T AddServiceDefaults<T>(this T builder, bool useOtlpExporter, bool isDevelopment)
        where T : IHostBuilder
    {
        builder.ConfigureOpenTelemetry(
            useOtlpExporter: useOtlpExporter,
            isDevelopment: isDevelopment);
        builder.AddDefaultHealthChecks();
        builder.AddServiceDiscovery();
        return builder;
    }

    public static T AddServiceDiscovery<T>(this T builder)
        where T : IHostBuilder
    {
        builder.ConfigureServices(services =>
        {
            services.AddServiceDiscovery();
        });
        return builder;
    }

    public static T ConfigureHttpClientDefaults<T>(this T builder)
        where T : IHostBuilder
    {
        builder.ConfigureServices(services =>
        {
            services.ConfigureHttpClientDefaults(http =>
            {
                // Turn on resilience by default
                http.AddStandardResilienceHandler();

                // Turn on service discovery by default
                http.UseServiceDiscovery();
            });
        });
        return builder;
    }

    public static T ConfigureOpenTelemetry<T>(this T builder, bool useOtlpExporter, bool isDevelopment)
        where T : IHostBuilder
    {
        builder.ConfigureLogging(logging =>
        {
            logging.AddOpenTelemetry(telemetry =>
            {
                telemetry.IncludeFormattedMessage = true;
                telemetry.IncludeScopes = true;
            });
        });

        builder.ConfigureServices(services =>
        {
            services.AddOpenTelemetry()
                .WithMetrics(metrics =>
                {
                    metrics.AddRuntimeInstrumentation()
                           .AddBuiltInMeters();
                })
                .WithTracing(tracing =>
                {
                    if (isDevelopment)
                    {
                        // We want to view all traces in development
                        tracing.SetSampler(new AlwaysOnSampler());
                    }

                    tracing.AddAspNetCoreInstrumentation()
                           .AddGrpcClientInstrumentation()
                           .AddHttpClientInstrumentation();
                });
        });

        builder.AddOpenTelemetryExporters(useOtlpExporter);

        return builder;
    }

    private static T AddOpenTelemetryExporters<T>(this T builder, bool useOtlpExporter)
        where T : IHostBuilder
    {
        builder.ConfigureServices(services =>
        {
            if (useOtlpExporter)
            {
                services.Configure<OpenTelemetryLoggerOptions>(logging => logging.AddOtlpExporter());
                services.ConfigureOpenTelemetryMeterProvider(metrics => metrics.AddOtlpExporter());
                services.ConfigureOpenTelemetryTracerProvider(tracing => tracing.AddOtlpExporter());
            }

            // Uncomment the following lines to enable the Prometheus exporter (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
            //services
            //    .AddOpenTelemetry();
            //    .WithMetrics(metrics => metrics.AddPrometheusExporter());

            // Uncomment the following lines to enable the Azure Monitor exporter (requires the Azure.Monitor.OpenTelemetry.Exporter package)
            //services
            //    .AddOpenTelemetry()
            //    .UseAzureMonitor();
        });
         
        return builder;
    }

    public static T AddDefaultHealthChecks<T>(this T builder)
        where T : IHostBuilder
    {
        builder.ConfigureServices(services =>
        {
            services.AddHealthChecks()
                // Add a default liveness check to ensure app is responsive
                .AddCheck("self", () => HealthCheckResult.Healthy(), ["live"]);
        });
        return builder;
    }

    public static WebApplication MapDefaultHealthCheckEndpoints(this WebApplication app)
    {
        // Uncomment the following line to enable the Prometheus endpoint (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
        // app.MapPrometheusScrapingEndpoint();

        // All health checks must pass for app to be considered ready to accept traffic after starting
        app.MapHealthChecks("/health");

        // Only health checks tagged with the "live" tag must pass for app to be considered alive
        app.MapHealthChecks("/alive", new HealthCheckOptions
        {
            Predicate = r => r.Tags.Contains("live")
        });

        return app;
    }

    private static MeterProviderBuilder AddBuiltInMeters(this MeterProviderBuilder meterProviderBuilder) =>
        meterProviderBuilder.AddMeter(
            "Microsoft.AspNetCore.Hosting",
            "Microsoft.AspNetCore.Server.Kestrel",
            "System.Net.Http");
}

Here are the app settings that are applied according to portal.azure.com

{
    "deployment_branch": "master",
    "SCM_TRACE_LEVEL": "Verbose",
    "SCM_COMMAND_IDLE_TIMEOUT": "60",
    "SCM_LOGSTREAM_TIMEOUT": "7200",
    "SCM_BUILD_ARGS": "",
    "AzureWebJobsStorage": "DefaultEndpointsProtocol=https;AccountName=...AccountKey=...=;EndpointSuffix=core.windows.net",
    "AzureWebJobsSecretStorageType": "Blob",
    "WEBSITE_USE_PLACEHOLDER_DOTNETISOLATED": "1",
    "APPLICATIONINSIGHTS_CONNECTION_STRING": "InstrumentationKey=...IngestionEndpoint=https://eastus-8.in.applicationinsights.azure.com/;LiveEndpoint=https://eastus.livediagnostics.monitor.azure.com/",
    "WEBSITE_SLOT_NAME": "Production",
    "SCM_USE_LIBGIT2SHARP_REPOSITORY": "0",
    "WEBSITE_SITE_NAME": "...",
    "FUNCTIONS_EXTENSION_VERSION": "~4",
    "WEBSITE_AUTH_ENABLED": "False",
    "ScmType": "None",
    "WEBSITE_RUN_FROM_PACKAGE": "1",
    "FUNCTIONS_WORKER_RUNTIME": "dotnet-isolated"
}