Cloud Native Week - Java Edition
Sommaire
Introduction
The goal of this project is to reproduce a week long workshop where we took a todo app written in Go, and added on top of it:
- observability
- tracing
- metrics
- logs aggregation
- ci/cd pipeline
- alerting
- and some other "cloud native" things
This time, the point is to do it on my own, and with Java
1. Writing the application
1.1 Presentation
The first task is to write a "Todo" Java application. It allows for the execution of the following actions:
- create item
- find item by id
- find all items
- update item
- delete item by id
- delete all items
It exposes a REST interface and connects to H2 or MySQL. Here is a schema of the architecture:
Just for the sake of it, we went for a full reactive stack.
1.2 Executing the project
1.2.1 Pre-requisites
In order to execute the project locally you will need:
- java 11 or +
- maven
- docker
- docker-compose
1.2.2 Executing tests
- via the CLI
mvn clean verify
- Via the IDE (here we use
IntelliJ)
1.2.3 Starting the application
- Start the database (MySQL) with
docker-compose
docker-compose down && docker-compose up
- Start the application. The main class is
CloudNativeWeekJavaEditionApplication
- Execute CRUD operations
- Create items
✗|→ curl localhost:8080/items -w "\n"
✗|→ curl -H "content-type: application/json" -X POST localhost:8080/items -d '{"name": "item1", "state":"TODO"}' -w "\n"
{"id":1,"name":"item1","state":"TODO"}
✗|→ curl -H "content-type: application/json" -X POST localhost:8080/items -d '{"name": "item2", "state":"DOING"}' -w "\n"
{"id":2,"name":"item2","state":"DOING"}
✗|→ curl -H "content-type: application/json" -X POST localhost:8080/items -d '{"name": "item3", "state":"DONE"}' -w "\n"
{"id":3,"name":"item3","state":"DONE"}
✗|→ curl localhost:8080/items -w "\n"
{"id":1,"name":"item1","state":"TODO"}
{"id":2,"name":"item2","state":"DOING"}
{"id":3,"name":"item3","state":"DONE"}
- Update item
✗|→ curl -H "content-type: application/json" -X PUT localhost:8080/items/2 -d '{"id": 2, "name": "item2", "state":"DONE"}' -w "\n"
{"id":2,"name":"item2","state":"DONE"}
✗|→ curl localhost:8080/items -w "\n"
{"id":1,"name":"item1","state":"TODO"}
{"id":2,"name":"item2","state":"DONE"}
{"id":3,"name":"item3","state":"DONE"}
- Delete item by id
✗|→ curl -X DELETE localhost:8080/items/2 -w "\n"
✗|→ curl localhost:8080/items -w "\n"
{"id":1,"name":"item1","state":"TODO"}
{"id":3,"name":"item3","state":"DONE"}
- Delete all items
✗|→ curl -X DELETE localhost:8080/items -w "\n"
✗|→ curl localhost:8080/items -w "\n"
✗|→