Support `otel.javaagent.add-thread-details` with declarative config

[zeitlinger]

Blocked by #14132

Is your feature request related to a problem? Please describe.

opentelemetry-java-instrumentation/javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/AgentTracerProviderConfigurer.java

Line 22 in 3122897

public class AgentTracerProviderConfigurer implements AutoConfigurationCustomizerProvider {

uses AutoConfigurationCustomizerProvider - which is not used with file config

@jack-berg what is the reason for not supporting this callback?

Describe the solution you'd like

Use DeclarativeConfigurationCustomizer instead

https://github.com/open-telemetry/opentelemetry-java/blob/000fd0f20919efbcb7e39e1ca493a246e0eb3dde/sdk-extensions/incubator/src/main/java/io/opentelemetry/sdk/extension/incubator/fileconfig/DeclarativeConfigurationCustomizer.java#L12

[laurit]

@zeitlinger is this customization also missing from the spring starter?

[zeitlinger]

@zeitlinger is this customization also missing from the spring starter?

yes - great hint

I think this can also be added with this issue by moving to the same project as ResourceProviderPropertiesCustomizer

[jack-berg]

@jack-berg what is the reason for not supporting this callback?

No strong reason. If you recall, we had conversations around DeclarativeConfigurationCustomizer about expanding the set of callbacks as needed, rather than trying to duplicate all the capabilities of AutoConfigurationCustomizerProvider. The idea being, to the extent possible, we should encourage customization requirements to be represented in the the declarative config data model.

[zeitlinger]

@jack-berg what is the reason for not supporting this callback?

No strong reason. If you recall, we had conversations around DeclarativeConfigurationCustomizer about expanding the set of callbacks as needed, rather than trying to duplicate all the capabilities of AutoConfigurationCustomizerProvider. The idea being, to the extent possible, we should encourage customization requirements to be represented in the the declarative config data model.

Thanks - that's great input for #14080

[zeitlinger]

@jack-berg I got stuck - how to I add a span processor here - specifically https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/AddThreadDetailsSpanProcessor.java ?

public class ThreadDetailsConfigurationCustomizerProvider implements
    DeclarativeConfigurationCustomizerProvider {
  @Override
  public void customize(DeclarativeConfigurationCustomizer customizer) {
    customizer.addModelCustomizer(
        model -> {
          model.getTracerProvider().getProcessors().add(new SpanProcessorModel() {

          });
          return model;
        });
  }
}