OpenTelemetry Demo Application with Spring Boot

This is a demo application that shows how to integrate OpenTelemetry in a Spring Boot application. The application consists of two services: api and product. The api service calls the product service several times requesting some products to return. The application uses Jaeger to visualize the traces.

Prerequisites

• Java 17
• Maven
• Docker
• Docker Compose

Building the Application

The project uses two maven modules. To build the application, run the following command in the root directory of the project:

mvn clean package

This will build the application and generate two JAR files in their respective target folders (api-service/target and product-service/target).

Building the Docker Image

To build the Docker image, run the following command in the root directory of the project:

docker build -t oteldemo/api-service api-service
docker build -t oteldemo/product-service product-service

This will build the Docker images for both components.

Running the Application with Docker Compose

To run the application with Docker Compose, run the following command in the root directory of the project:

docker-compose up

This will start four containers: both applications, Jaeger and the open-telemetry-collector.

Accessing the Application

The application can be accessed at http://localhost:8080. Try calling:

curl http://localhost:8080/products

The response should be:

[{"name":"milk","category":"beverages"},{"name":"fruit","category":"food"},{"name":"bread","category":"food"}]

Accessing Jaeger

Jaeger can be accessed at http://localhost:16686.

Viewing Traces in Jaeger

To view traces in Jaeger, follow these steps:

1. Open Jaeger at http://localhost:16686.
2. Click on the service product-service.
3. Click on the Find Traces button.
4. Click on a trace to view its details.

You should see something like this: