Is there a way to add custom headers to all http requests and then add them to metrics?

[tuhao1020]

For traces we can create a custom ResourceProvider in extensions, can we do the same for metrics?
For example, add a new extension, add custom headers to all http requests, and then add them to metrics as dimensions.

[mateuszrzeszutek]

Hey @tuhao1020 ,

For traces we can create a custom ResourceProvider in extensions, can we do the same for metrics?

The same resource attributes are attached to all telemetry signals; if you register a ResourceProvider it will apply both to traces and metrics.

Is there a way to add custom headers to all http requests...

Like, append extra headers to outgoing HTTP client requests?
Propagators kinda do that, they allow injecting custom key-value pairs to outgoing message headers (that includes HTTP, RPC, messaging, etc).

You can also use baggage and the baggage propagator for that.

...and then add them to metrics as dimensions

If you're using baggage, you can append chosen baggage attributes to the metrics; that requires using an internal/experimental API though.

[tuhao1020]

this is the extension example code

@Override
  public void customize(AutoConfigurationCustomizer autoConfiguration) {
    autoConfiguration
        .addTracerProviderCustomizer(this::configureSdkTracerProvider)
        .addPropertiesSupplier(this::getDefaultProperties);
  }

and there is a DemoPropagator.java but seems not work, can you give me some more sample code?

[tuhao1020]

@mateuszrzeszutek can you show me how to register SdkMeterProvider to AutoConfigurationCustomizerProvider and then use SdkMeterProviderUtil.appendFilteredBaggageAttributes ?

[mateuszrzeszutek]

Try the following:

@AutoService(AutoConfigurationCustomizerProvider.class)
class SdkMeterProviderConfigurer implements AutoConfigurationCustomizerProvider {
  
  public void customize(AutoConfigurationCustomizer autoConfiguration) {
    autoConfiguration.addMeterProviderCustomizer((sdkMeterProviderBuilder, configProperties) -> {
      ViewBuilder viewBuilder = View.builder();
      SdkMeterProviderUtil.appendFilteredBaggageAttributes(viewBuilder, name -> name.equals("my-baggage-attribute"));
      View view = viewBuilder.build();
      return sdkMeterProviderBuilder.registerView(InstrumentSelector.builder().setName("http.client.duration").build(), view);
    });
  }
}