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Showing custom metrics in Aspire

After enabling Aspire for your application, you get OpenTelemetry integration for free thanks to the included ServiceDefaults code. 

This will setup OpenTelemetry using a set of defaults:

Unfortunately this default configuration didn’t pick up any of the custom metrics I added.

I first thought that this meant that I couldn’t use the service defaults anymore and configure the OpenTelemetry integration manually.

But then I discovered that you can change/extend the default configuration in a specific project by using the ConfigureOpenTelemetryTracerProvider and/or ConfigureOpenTelemetryMeterProvider methods.

Add your custom OpenTelemetry configuration after calling the Aspire builder.AddServiceDefaults():

Now our custom metrics appear nicely in the Aspire dashboard:

More information

Welcome to Aspire | Aspire

Enabling .NET Aspire for an existing solution

Replacing EventCounters with the new Metrics API

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