Get Data Samples from Java services¶

Warning

There is no Neblic SDK for Java, this guide shows how to send Data Samples as OpenTelemetry logs directly to the Collector

To add Samplers in your code that export Data Samples you first need to initialize a SdkLoggerProvider. A SdkLoggerProvider receives a configuration that is then used to configure and initialize all the Loggers in your application.

import io.opentelemetry.api.common.AttributeKey;
import io.opentelemetry.api.logs.Logger;
import io.opentelemetry.exporter.otlp.logs.OtlpGrpcLogRecordExporter;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.logs.SdkLoggerProvider;
import io.opentelemetry.sdk.logs.export.BatchLogRecordProcessor;
import io.opentelemetry.sdk.resources.Resource;
import io.opentelemetry.semconv.resource.attributes.ResourceAttributes;

public final class SamplerExample {

  ...

  private static SdkLoggerProvider initProvider() {
    OpenTelemetrySdk otelSdk = OpenTelemetrySdk.builder()
        .setLoggerProvider(
            SdkLoggerProvider.builder()
                .setResource(
                    Resource.getDefault().toBuilder()
                        .put(ResourceAttributes.SERVICE_NAME, "service-name")
                        .build())
                .addLogRecordProcessor(
                    BatchLogRecordProcessor.builder(
                        OtlpGrpcLogRecordExporter.builder()
                            .setEndpoint("http://" + System.getenv("COLLECTOR_SERVICE_ADDR"))
                            .build())
                        .build())
                .build())
        .buildAndRegisterGlobal();

    return otelSdk.getSdkLoggerProvider();
  }

  ...

}

Once the SdkLoggerProvider is initialized, you can use it to initialize a Logger. To do that, you will need to call the get method of your provider.

public final class SamplerExample {

  ...

  private static Logger initSampler(SdkLoggerProvider provider) {
    return provider.get("sampler-name");
  }

  ...

}

Once you have initialized the Logger, you have to create a LogRecordBuilder, set the required attributes and body, and call the emit function to send the Data Sample.

Note

Full list of parameters to provide to the LogRecord can be found in learn about opentelemetry samplers

public final class SamplerExample {

  ...

  private static void sampleData(Logger sampler, String data) {
    sampler.logRecordBuilder()
        .setAttribute(AttributeKey.stringArrayKey("com.neblic.sample.stream.names"), Arrays.asList("all"))
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.type"), "raw")
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.key"), "")
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.encoding"), "json")
        .setBody(data)
        .emit();
  }

  ...

}

Full example¶

If we put everything together, we get the following.

package sampler_example;

import java.util.Arrays;

// --8<-- [start:InitImport]
import io.opentelemetry.api.common.AttributeKey;
import io.opentelemetry.api.logs.Logger;
import io.opentelemetry.exporter.otlp.logs.OtlpGrpcLogRecordExporter;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.logs.SdkLoggerProvider;
import io.opentelemetry.sdk.logs.export.BatchLogRecordProcessor;
import io.opentelemetry.sdk.resources.Resource;
import io.opentelemetry.semconv.resource.attributes.ResourceAttributes;
// --8<-- [end:InitImport]

public final class SamplerExample {

  // --8<-- [start:ProviderInit]
  private static SdkLoggerProvider initProvider() {
    OpenTelemetrySdk otelSdk = OpenTelemetrySdk.builder()
        .setLoggerProvider(
            SdkLoggerProvider.builder()
                .setResource(
                    Resource.getDefault().toBuilder()
                        .put(ResourceAttributes.SERVICE_NAME, "service-name")
                        .build())
                .addLogRecordProcessor(
                    BatchLogRecordProcessor.builder(
                        OtlpGrpcLogRecordExporter.builder()
                            .setEndpoint("http://" + System.getenv("COLLECTOR_SERVICE_ADDR"))
                            .build())
                        .build())
                .build())
        .buildAndRegisterGlobal();

    return otelSdk.getSdkLoggerProvider();
  }
  // --8<-- [end:ProviderInit]

  // --8<-- [start:SamplerInit]
  private static Logger initSampler(SdkLoggerProvider provider) {
    return provider.get("sampler-name");
  }
  // --8<-- [end:SamplerInit]

  // --8<-- [start:SampleData]
  private static void sampleData(Logger sampler, String data) {
    sampler.logRecordBuilder()
        .setAttribute(AttributeKey.stringArrayKey("com.neblic.sample.stream.names"), Arrays.asList("all"))
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.type"), "raw")
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.key"), "")
        .setAttribute(AttributeKey.stringKey("com.neblic.sample.encoding"), "json")
        .setBody(data)
        .emit();
  }
  // --8<-- [end:SampleData]

  public static void main(String[] args) throws InterruptedException {

    SdkLoggerProvider provider = initProvider();
    Logger sampler = initSampler(provider);
    sampleData(sampler, "{\"foo\": 1, \"bar\": \"baz\"}");
  }
}