Auto-configure EventLoggerProvider

[swar8080]

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

We're looking to use the Events API but currently have to build an EventLogger manually. It's error-prone getting the manual set-up to use all the auto-configuration that we're used to the java agent doing for us. For example, our attempt is:

  <dependency>
    <groupId>io.opentelemetry</groupId>
    <artifactId>opentelemetry-api-incubator</artifactId>
  </dependency>
  <dependency>
    <groupId>io.opentelemetry</groupId>
    <artifactId>opentelemetry-sdk-extension-autoconfigure</artifactId>
    <version>${opentelemetry.version}</version>
  </dependency>
  <dependency>
    <groupId>io.opentelemetry</groupId>
    <artifactId>opentelemetry-sdk-extension-autoconfigure-spi</artifactId>
    <version>${opentelemetry.version}</version>
  </dependency>
  <dependency>
    <groupId>io.opentelemetry.instrumentation</groupId>
    <artifactId>opentelemetry-resources</artifactId>
    <version>${opentelemetry.javaagent.version}-alpha</version>
  </dependency>
  <dependency>
    <groupId>io.opentelemetry</groupId>
    <artifactId>opentelemetry-exporter-otlp</artifactId>
    <version>${opentelemetry.version}</version>
  </dependency>
...
  @Bean
  EventLogger otelEventLogger() {
    var autoOtelSdk = AutoConfiguredOpenTelemetrySdk.builder().build();
    var otelConfig = AutoConfigureUtil.getConfig(autoOtelSdk);
    if (otelConfig == null) {
      logger.info(
          "No OTEL ConfigProperties available for EventLogger. Using empty configuration instead");
      otelConfig = DefaultConfigProperties.create(new HashMap<>());
    }

    Resource resource = Resource.getDefault();
    ServiceLoader<ResourceProvider> serviceLoader = ServiceLoader.load(ResourceProvider.class);
    for (ResourceProvider provider : serviceLoader) {
      Resource provided = provider.createResource(otelConfig);
      resource = resource.merge(provided);
    }

    OtlpGrpcLogRecordExporter exporter =
        OtlpGrpcLogRecordExporter.builder()
            .setRetryPolicy(
                RetryPolicy.builder()
                    .setMaxAttempts(5)
                    .setMaxBackoff(Duration.ofSeconds(3L))
                    .build())
            .build();
    BatchLogRecordProcessor processor =
        BatchLogRecordProcessor.builder(exporter)
            .setMeterProvider(GlobalOpenTelemetry.getMeterProvider())
            .build();
    SdkLoggerProvider loggerProvider =
        SdkLoggerProvider.builder().setResource(resource).addLogRecordProcessor(processor).build();

    EventLoggerProvider eventLoggerProvider = SdkEventLoggerProvider.create(loggerProvider);
    return eventLoggerProvider.eventLoggerBuilder("com.demo").build();
  }

Describe the solution you'd like

Have the javaagent auto-configure the EventLoggerProvider and expose it for applications.

@jack-berg had a suggestion for how to do this: https://cloud-native.slack.com/archives/C014L2KCTE3/p1718657558881159?thread_ts=1718293157.542669&cid=C014L2KCTE3

Describe alternatives you've considered

• Agent extension?
• Manual set-up

Additional context

Any guesses if packaging our manual set-up in an agent extension would work as a temporary solution? Or would the call GlobalEventLoggerProvider.set happen using a different class loader than what's available to the application?

[JonasKunz]

I also stumbled across this issue. In fact, the SDK shipped with the agent does configure the GlobalEventLoggerProvider.
This means if you for example write an agent extension or custom instrumentation, it will be able to access the GlobalEventLoggerProvider.

What however is not yet implemented is to support the GlobalEventLoggerProvider via the opentelemetry-api-instrumentation: That instrumentation is responsible for redirecting opentelemtry-API classes shipped with the instrumented application to the opentelemetry-SDK contained in the agent.
This redirection is not yet implemented there for the GlobalEventLoggerProvider.

[trask]

the event api (as currently implemented) is going away, so unless this is urgently needed, I'd suggest waiting for open-telemetry/opentelemetry-java#6761 (also see https://github.com/open-telemetry/opentelemetry-specification/blob/main/oteps/0265-event-vision.md#api)