MyObservability

Manual Instrumentation

To facilitate the instrumentation of applications even more, you can manually instrument your applications by coding against the OpenTelemetry APIs.

To apply a more granular configuration to the already existing agent you can use the opentelemetry-instrumentation-annotations library.

Also some language do not support auto instrumentation.

Steps:

1. Import the OpenTelemetry API and SDK
2. Configure the OpenTelemetry API
3. Configure the OpenTelemetry SDK
4. Create Telemetry Data
5. Export Data

Manual Instrumentation - Tracing

Big Picture: OpenTelemetry Tracing Pipeline

1. OpenTelemetry Tracing API
2. OpenTelemetry SDK
   • Telemetry Generation
     • TraceProvider
     • Tracer
   • Tracing Pipeline
     • SpanProcessor
     • SpanExporter

OpenTelemetry Tracing API

The API is what you use in your code to generate trace data. It’s just interfaces (no logic) that define how you:

• Create spans
• Set attributes
• Link spans
• Propagate context

Ex:

Tracer tracer = GlobalOpenTelemetry.getTracer("my-app");

Span span = tracer.spanBuilder("fetchData").startSpan();
try (Scope scope = span.makeCurrent()) {
    // business logic
    span.setAttribute("user.id", "123");
} finally {
    span.end();
}

OpenTelemetry SDK

The SDK is the actual implementation of the API. It provides the logic to:

• Record spans
• Process spans (e.g., sampling, filtering)
• Export them to telemetry backends

You typically bring in this SDK in your app as a dependency.

Ex:

<dependency>
  <groupId>io.opentelemetry</groupId>
  <artifactId>opentelemetry-sdk</artifactId>
  <version>1.34.1</version>
</dependency>

• TracerProvider (SDK): It’s the factory that gives you Tracer instances. You configure it to control the tracing pipeline.
• Tracer: The Tracer is the main object your app uses to create and manage spans. Each tracer, Starts spans, Links to parent spans, Lets you manage attributes and events
• SpanProcessor: A middleware between the creation of a span and its export. You can add multiple span processors
  • SimpleSpanProcessor (exports immediately).
  • BatchSpanProcessor (exports in batches — better for production)
  • Custom processors (e.g., for filtering, metrics enrichment)
• SpanExporter: This is the final destination handler — it sends your span data to a backend like: OpenTelemetry Collector Or / And to Grafana Tempo, Splunk Or File or console.

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Next Chapter: Sampling

Main Page: Click Here

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