/spring-cloud-event-sourcing-example

Spring Cloud reference application for building an online store as microservices that use event sourcing

Primary LanguageJavaApache License 2.0Apache-2.0

Spring Cloud Event Sourcing Example

This reference application is a Spring Cloud example of using event sourcing in microservices. The project is intended to demonstrate end-to-end best practices for building a Netflix-like microservice architecture using Spring Cloud.

Tutorial provided here: http://www.kennybastani.com/2016/04/event-sourcing-microservices-spring-cloud.html

  • Spring Cloud OAuth2
    • Authorization Server
    • Resource Server
  • Edge Service
    • API gateway with OAuth2 protected resources
    • OAuth2 SSO
  • Event-driven Messaging
    • Event sourcing

Architecture Diagram

Online Store Architecture Diagram

Online Store Domain

This reference application is based on common design patterns for building an ecommerce application. The application includes the following microservices.

  • Discovery Service
  • Edge Service
  • User Service
  • Catalog Service
  • Account Service
  • Order Service
  • Inventory Service
  • Online Store Web
  • Shopping Cart Service

Usage

Microservice architectures commonly use multiple databases. The resources of the business domain are distributed across the microservice architecture, with each service having its own exclusive database. Each type of database for a microservice is commonly chosen by a development team based on its advantages when solving a specific problem.

This reference application uses the following mixture of databases.

  • MySQL - RDBMS
  • Neo4j - GraphDB
  • MongoDB - Document Store
  • Redis - Key/value Store

Integration Testing

If you would like to use Docker for integration testing, a docker-compose.yml file has been provided in the root directory. To build all the images, first make sure that you have Docker installed and available in your command line tool. With Docker and Docker Compose installed, execute the provided run.sh script. This script will build each container and start each of the services and database dependencies. When all the services have started up. Verify that the services are registered with Eureka at http://$DOCKER_IP:8761.

If everything has loaded correctly, navigate to the online store at http://DOCKER_IP:8787/. Click Login. You'll be navigated to the authorization server's gateway at http://DOCKER_IP:8181/uaa/login. The username is user and the password is password. You'll be authenticated and asked to approve token grant to the online web store. After accepting the grant, you'll be redirected to the online store application where you'll be able to access protected resources from the edge service.

License

This project is licensed under Apache License 2.0.