Azure Voting App (.NET)

This sample is the .NET implementation of the official Azure Voting App. This sample creates a multi-container application in a Kubernetes cluster like the original one.

The application interface is built using ASP.NET Core Blazor Server. The data component uses Redis.

This sample also includes the following features:

1. Instrumented to produce OpenTelemetry traces and export the traces to the console.
2. Request to GET /traced-exception endpoint will throw an exception. It shows how unhandled exceptions are logged in the active OpenTelemtry span.
3. Instrumented to emit built-in .NET metrics and custom metrics with the OpenTelemetry Metrics SDK.
4. Deployment with Helm, Kubernetes manifest, or Docker compose.

Note

1. The previous version of this application used prometheus-net to expose metrics to Prometheus on the /metrics endpoint. The main branch uses OTEL Metrics SDK to send metrics to the destination. You can use the commit tagged prometheus-metrics to refer to the previous version of the application.
2. The application sends traces and metrics to the console exporter by default. You can set the environment variable EnableOtlpExporter to true to send traces and metrics to the local OTEL collector. Update the values of the connection strings OTLPMetricsExporterEndpoint and OTLPTracesExporterEndpoint if you want to send the metrics and traces to a remote OTLP endpoint. You can launch the application and the local OTEL collector with the following command:

docker-compose --profile local-collector up

Demo