[AspNetCore] [WorkerService] Setting the connection string throws exception when using the ConnectionString property in the appsettings json.

[harsimar]

Applies to:

• Version: 3.0.0-beta1
• AspNetCore webapps & Worker Service

Issue: When setting the connection as below in appsettings.json, the underlying exporter will throw an exception saying that the connection string is not set.

"ApplicationInsights": { "ConnectionString" : "<YOUR-CONNECTION-STRING>" }

The exception: System.InvalidOperationException: A connection string was not found. Please set your connection string. at Azure.Monitor.OpenTelemetry.Exporter.Internals.AzureMonitorTransmitter.InitializeConnectionVars(AzureMonitorExporterOptions options, IPlatform platform) at Azure.Monitor.OpenTelemetry.Exporter.Internals.AzureMonitorTransmitter..ctor(AzureMonitorExporterOptions options, IPlatform platform) at Azure.Monitor.OpenTelemetry.Exporter.Internals.TransmitterFactory.Get(AzureMonitorExporterOptions azureMonitorExporterOptions, IPlatform platform) at Azure.Monitor.OpenTelemetry.Exporter.Internals.TransmitterFactory.Get(AzureMonitorExporterOptions azureMonitorExporterOptions) at Azure.Monitor.OpenTelemetry.Exporter.AzureMonitorMetricExporter..ctor(AzureMonitorExporterOptions options) at Azure.Monitor.OpenTelemetry.Exporter.OpenTelemetryBuilderExtensions.<>c__DisplayClass1_0.<UseAzureMonitorExporter>b__2(IServiceProvider serviceProvider, MeterProviderBuilder meterProviderBuilder) at OpenTelemetry.Metrics.OpenTelemetryDependencyInjectionMetricsServiceCollectionExtensions.ConfigureMeterProviderBuilderCallbackWrapper.ConfigureBuilder(IServiceProvider serviceProvider, MeterProviderBuilder meterProviderBuilder) at OpenTelemetry.Metrics.MeterProviderSdk..ctor(IServiceProvider serviceProvider, Boolean ownsServiceProvider) at OpenTelemetry.Metrics.MeterProviderBuilderBase.<>c.<.ctor>b__3_0(IServiceProvider sp) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitFactory(FactoryCallSite factoryCallSite, RuntimeResolverContext context) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitRootCache(ServiceCallSite callSite, RuntimeResolverContext context) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(ServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext ....

Workaround: Setting the connection string via the env var (APPLICATIONINSIGHTS_CONNECTION_STRING) or code still works.