Order a product using Spring CLoud Axon Framework, CQRS, Event Sourcing, SAGA, Transactions

Learn to build distributed Event-driven Microservices, CQRS, Event Sourcing, SAGA, Transactions

There are four microservices:

• Products : This microservice is responsible for managing products. A user can create, update, get details, list and delete products.
• Orders : This microservice is responsible for managing orders. A user can order many products.
• Payment : This microservice is responsible for managing payments. Save details about the payment associated with the order.
• Users : This microservice is responsible for managing users. Save details about the user.

Concepts used

• Event-Driven Microservices
• Basics of Spring Cloud
• Axon Framework
• Eureka Discovery Service
• CQRS Design Pattern
• Spring Cloud API Gateway
• SAGA Design Pattern
• Event Based Messages
• Transactions

EndPoints

Service	EndPoint	Method	Description
Orders	/orders	POST	Create an order
Products	/products	GET	Return list of products
Products	/products/{id}	GET	Return details from a specific product
Products	/products	POST	Insert a new product
Products	/products/{id}	PUT	Update a specific product
Products	/products/{id}	DELETE	Delete a specific product
Users	/users/{userId}/payment-details	GET	Return details from a userfor payment based on your ID

Gateways

Service	EndPoint
Products	/products/{id}
Products	/products
Orders	/orders
Users	/users/{userId}/payment-details

URI for gateway : http://localhost:8082

Documentation and examples

###Swagger

• Products : http://localhost:8082/products/swagger-ui.html
• Orders : http://localhost:8082/orders/swagger-ui.html
• Users : http://localhost:8082/users/swagger-ui.html

###Postman collection

Used Netflix OSS:

• Netflix Eureka is used for discovery service.
• Netflix Zuul is used for gateway.

Distributed Tracing:

• Sleuth and Zipkin

You can open Zipkin : http://localhost:9411

Used ELK STACK:

• ElasticSearch is on 6972 port
• Logstash TCP is on 5000 port
• Kibana is on 5601 port

Open kibana with http://localhost:5601/. You must define an index pattern (taner-*) on Management/Stack Management.

Grafana:

You can open Grafana : http://localhost:3000/

username/password: admin

Build & Run

• >mvn clean package : to build
• >docker-compose up --build : build docker images and containers and run containers
• >docker-compose stop : stop the dockerized services
• Each maven module has a Dockerfile.

In docker-compose.yml file:

• Books Service : 7500 port is mapped to 7500 port of host
• Orders Service : 7501 port is mapped to 7501 port of host
• Params Service : 7502 port is mapped to 7502 port of host
• Eureka Discovery Service : 8761 port is mapped to 8761 port of host
• Spring Boot (/ Zuul) Gateway Service : 8762 port is mapped to 8762 port of host

VERSIONS

1.0.0

• Sleuth and Zipkin Integration
• ElasticSearch, Kibana, Logstash integration
• Spring Boot Gateway
• Spring-Boot 2.5.7.RELEASE
• Java 16