OpenTelemetry is an open-source observability framework that allows developers to collect and manage telemetry data from distributed systems. In this article, we’ll explore how to set up OpenTelemetry in a Spring Boot application to capture and export tracing and metrics data.
By integrating OpenTelemetry into our Spring Boot application, we can gain valuable insights into the performance and behavior of our system, enabling us to identify and troubleshoot issues more effectively.
Prerequisites
Before we begin, ensure that you have the following prerequisites:
- Basic knowledge of Spring Boot
- JDK 8 or higher installed
- Maven or Gradle build tool installed (depending on your project setup)
Step 1: Add OpenTelemetry Dependencies
To start using OpenTelemetry in our Spring Boot application, we need to add the necessary dependencies to our project.
If you’re using Maven, add the following dependencies to your pom.xml file:
<dependency><groupId>io.opentelemetry</groupId><artifactId>opentelemetry-api</artifactId><version>1.6.0</version></dependency><dependency><groupId>io.opentelemetry</groupId><artifactId>opentelemetry-sdk</artifactId><version>1.6.0</version></dependency><dependency><groupId>io.opentelemetry</groupId><artifactId>opentelemetry-exporters-logging</artifactId><version>1.6.0</version></dependency><dependency><groupId>io.opentelemetry</groupId><artifactId>opentelemetry-exporters-jaeger</artifactId><version>1.6.0</version></dependency>For Gradle users, add the following dependencies to your build.gradle file:
implementation 'io.opentelemetry:opentelemetry-api:1.6.0'
implementation 'io.opentelemetry:opentelemetry-sdk:1.6.0'
implementation 'io.opentelemetry:opentelemetry-exporters-logging:1.6.0'
implementation 'io.opentelemetry:opentelemetry-exporters-jaeger:1.6.0'Step 2: Configure OpenTelemetry
Next, we need to configure OpenTelemetry in our Spring Boot application. Create a new Java class, OpenTelemetryConfig, and annotate it with @Configuration. In this class, we’ll define the necessary beans for OpenTelemetry.
import io.opentelemetry.exporter.logging.LoggingMetricExporter;
import io.opentelemetry.exporter.logging.LoggingSpanExporter;
import io.opentelemetry.exporter.jaeger.JaegerGrpcSpanExporter;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.metrics.export.IntervalMetricReader;
import io.opentelemetry.sdk.metrics.export.MetricExporter;
import io.opentelemetry.sdk.trace.export.SpanExporter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configurationpublic class OpenTelemetryConfig {
@Beanpublic OpenTelemetrySdk openTelemetrySdk() {
return OpenTelemetrySdk.builder()
.setTracerProvider(...)
.setMeterProvider(...)
.build();
}
@Beanpublic SpanExporter spanExporter() {
return JaegerGrpcSpanExporter.builder().build();
}
@Beanpublic MetricExporter metricExporter() {
return LoggingMetricExporter.builder().build();
}
@Beanpublic LoggingSpanExporter loggingSpanExporter() {
return LoggingSpanExporter.builder().build();
}
@Bean
public IntervalMetricReader intervalMetricReader(MetricExporter metricExporter) {
return IntervalMetricReader.builder()
.setMetricExporter(metricExporter)
.setExportIntervalMillis(5000)
.build();
}
} In the OpenTelemetryConfig class, we define beans for OpenTelemetrySdk, SpanExporter, MetricExporter, and LoggingSpanExporter. Customize the configurations according to your needs. For example, you can choose a different span exporter like Zipkin or customize the metric exporter.
Step 3: Instrument Your Application
With OpenTelemetry configured, we can now instrument our Spring Boot application to capture telemetry data. OpenTelemetry provides various instrumentation libraries for different frameworks and libraries.
For example, to instrument HTTP requests, add the following dependency to your project:
<dependency>
<groupId>io.opentelemetry.instrumentation</groupId>
<artifactId>opentelemetry-instrumentation-spring-web</artifactId>
<version>1.6.0</version>
</dependency>To instrument database calls, add the appropriate instrumentation library for your database, such as opentelemetry-instrumentation-jdbc or opentelemetry-instrumentation-hibernate.
You can find the available instrumentation libraries in the OpenTelemetry GitHub repository.
Step 4: Export Telemetry Data
Finally, we need to export the captured telemetry data to an external system for analysis. In this example, we’ll export the span data to a Jaeger backend using the Jaeger exporter.
To export the span data, make sure you have a Jaeger backend running. You can install it locally or use a cloud-based Jaeger service. Configure the Jaeger exporter in the OpenTelemetryConfig class:
@Beanpublic SpanExporter spanExporter() {
return JaegerGrpcSpanExporter.builder()
.setEndpoint("http://localhost:14250")
.build();
}Make sure to replace the http://localhost:14250 with the correct URL for your Jaeger backend.
Step 5: Run and Verify
With OpenTelemetry configured and instrumented, you can now run your Spring Boot application and verify that the telemetry data is being captured and exported.
Access your application and perform various actions to generate telemetry data. Then, use the Jaeger UI or your preferred observability tool to view the captured spans and analyze the performance and behavior of your application.
Conclusion
In this article, we explored how to set up OpenTelemetry in a Spring Boot application to capture and export telemetry data. By integrating OpenTelemetry, you can gain valuable insights into the performance and behavior of your application, enabling you to identify and address issues effectively.
Remember to configure the necessary dependencies, set up the OpenTelemetry beans, instrument your application with the appropriate libraries, and export the telemetry data to your preferred backend. With OpenTelemetry in place, you can improve the observability of your Spring Boot application and gain a deeper understanding of its behavior.
