demo-tracing

Introduction

The aim of this project is to demonstrate the use of tracing opentelemetry with Java and Spring Boot.

The opentelemetry project is an attempt to unify a complex, vendor-specific multitude of SDKs, agents and configuration procedures, thereby allowing to make projects vendor-specific and independent from their specific SDKs.

A change of vendor will therefore not have any impact on the code base, just on configuration.

This project only covers the distributed tracing for a very simple architecture (one service + mongoDB), using (to my knowledge) the state of the art and prioritising the use of OTLP over vendor-specific protocols, in order to achieve maximum vendor independence.

Collection of logs and metrics is out of scope.

High level design

This project implements this kind of deployment, as described here

A few clarifications:

• the Application is a dummy Spring Boot REST API
• instead of using the OpenTelemetry SDK, I opted for letting the opentelemetry-javaagent attach to the JVM and collect traces (Zero-code instrumentation). Code-based instrumentation is also possible
• the OpenTelemtry Collector is deployed via docker, see compose.yml, and is configured in collector-config.yml to receive and export data via OTLP (OpenTelemetry Protocol)
• the Backend is Jaeger, but any tool to visualize distributed traces will do. I chose Jaeger because it's opensource, easy to get up&running and supports OTLP. It can be further integrated into a full observability solution thanks to Grafana (out of scope)

Quick start

Assuming you have docker and docker-compose installed, you have to:

• start the dependencies via compose, for example by opening a shell into the project directory and entering docker compose up -d and wait for them to be up&running
• start the service by executing ./run.sh (tested on Linux).

Should you use a different shell, you'll have to create your own run script by taking the commands found in run.sh.

Send a request to the REST API via curl localhost:8080/persons.

Open the Jaeger web UI at localhost:16686 and you should see a new trace.

Feedback

For any feedback or appreciation, feel free to reach out via the Issues section or Star this repo 🙏.

I'm also on LinkedIn.