thedevopsstore / spring-boot-kafka

SRE Coding Challenge

You are tasked with deploying a solution to Kubernetes cluster. You may use Minikube, Microk8s, k3s or any other Kubernetes distribution
Solution consists of 3 SpringBoot applications, Kafka deployment to support messaging and PostgreSQL database to provide persistence layer. Application deployment should use helm (https://helm.sh/), Kafka and Postgres may be deployed with any technology you like.

We do not expect too much automation (few bash scripts should work just fine). In case you prefer to automate everything, you may use any flavour of automation tools, Ansible, Terraform - everything will work, You may even setup CI/CD flow using Jenkins/Tekton/Drone/etc. ;)

Overall architecture

Deployment layout

Kafka Topic specs

• name: testCommand
• partitions: 32
• replication-factor: 1

Database

Application developed with PostgreSQL 11.5

Database schema created with Back application first run

Applications

Build applications

You need Java 11+ installed, then run

./gradlew clean build

to build applications. Jar files will land in app/back/build/libs/back-0.1.0.jar (Back app for instance)

Hints

Few hints to simplify application deployment.

Docker: ENTRYPOINT ["java", "-jar", "/app.jar"]

SpringBoot additional config arg if needed. Additional config values will override default. --spring.config.additional-location=path-to-additional-config

Health check exposed as http://localhost:{management.server.port}/health

Applications expose API management interface as http://localhost:{server.port}/swagger-ui.html

Front

Sample application configuration application.yaml file

server.port: 8080
################### Kafka ##############################
spring:
  kafka:
    bootstrap-servers:  {{ kafka-bootstrap-goes here }}

################### Logging settings ###################
logging:
  level:
    root: WARN
    db.demo: INFO

management.server.port: 8081

Back

Sample application configuration application.yaml file

spring:
  kafka:
    bootstrap-servers: {{ kafka-bootstrap-goes here }}
  datasource.url: jdbc:postgresql://localhost:5432/postgres
  datasource.username: {{ username }}
  datasource.password: {{ password }}

management.server.port: 8081

Hint: You may use Spring Boot relaxed binding to pass parameters through environment variables https://docs.spring.io/spring-boot/docs/2.1.8.RELEASE/reference/html/boot-features-external-config.html#boot-features-external-config-relaxed-binding

SPRING_DATASOURCE_USERNAME=postgres

Reader

Sample application configuration application.yaml file

spring:
  datasource.url: jdbc:postgresql://localhost:5432/postgres
  datasource.username: {{ username }}
  datasource.password: {{ password }}

management.server.port: 8081