example

Monitoring applications with OpenTelemetry: a practical example

Requirements

• Go 1.17+
• Docker
• Docker compose
• Make

Run the dependencies

make compose-dependencies 

Run the applications

All the applications are instrumented and exporting the data to Jaeger, which is started when running the dependencies.

make run-root
make run-http
make run-events

• cmd/root

Is an HTTP server listening on port 4242. It makes a HTTP request to cmd/http

• cmd/http

Is an HTTP server and a Kafka producer, the HTTP server runs on port 1618 by default. There are two endpoints:

• /: produces an event to the kafka topic otel-example

• /final: logs and responds with the inbound request headers

• cmd/events:

Is a Kafka consumer which consumer from the topic otel-example and then calls http://localhost:1618/final

After all applications are running, call http://localhost:4242 a few times. Check the logs, and head to Jaeger UI to see the traces.

Clean up

• To stop the containers:

make compose-down

• To clean up, erase the data and remove volumes:

make clean