Customer Service

simulating 3rd party backend api

Microservice Architecture

 --------------------             ------------------            ------------------      
| Client(UI/Browser) | =======> | Front api service | =======> | Customer service |   
 --------------------             ------------------            ------------------

Execute using IDE/command line

1. Start the customer service using command: mvn spring-boot:run
2. Start the front api service (reference link given below)
3. Open browser: http://localhost:8080/customerDetails/1 (Remember: start the Front api service first !)

Reference: Front api service

Execute using Docker

1. Start the customer service
docker network create tracing
docker pull rduttaxebia/otel-demo-customer-service:latest
docker run --name customer-service --network tracing -p 8081:8081 rduttaxebia/otel-demo-customer-service:latest

2. Start the front-api-service using Docker. Reference link is mentioned above.

Enable OpenTelemetry

1. Add the following dependencies in pom.xml

		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-sleuth-zipkin</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-sleuth</artifactId>
		</dependency>

2. Add/append the following in application.yml

server.port: 8081

spring:
    application:
        name: customer-service
    zipkin:
        baseUrl: http://localhost:9411
    sleuth:
        sampler:
            probability: 1.0 # allowed values between 0.0 - 0.1

3. Start a zipkin server using Docker (ignore if already started)

docker network create tracing
docker run -d --rm -it --name zipkin --network tracing -p 9411:9411 openzipkin/zipkin:latest

4. Restart the service

mvn spring-boot:run

Instrumenting by injecting agent during startup

export OTEL_EXPORTER_ZIPKIN_ENDPOINT=http://localhost:9411/api/v2/spans
export OTEL_TRACES_EXPORTER=zipkin
export OTEL_SERVICE_NAME=customer-service
java -javaagent:opentelemetry-javaagent.jar  -jar target/*.jar