How to start the project: ./mvnw spring-boot:run

There is a request folder. If you use Intellij Idea, you can use this basic http file to send requests to the API. There is also swagger-ui available at the default address: http://localhost:8080/swagger-ui/index.html

Implemented:

• Create new user with a user name. User names are unique.
• A user can send a message to another using the user's id. You cannot send a message to yourself.
• The messages are persisted in DB.
• It's possible to see the message that a user sent or received.
• Test for the User controller have been implemented
• End-to-end test of the User controller
• Unit tests on the messageService

Not implemented:

• I can view all messages received from a particular user.
• Sending messages through a messaging system.
• End-to-end test on the MessagesController
• Unit tests on the UserService

To do:

• Code quality
• Caching
• Test coverage
• Sanitize inputs of the controllers
• Proper implementation of filtering, pagination and sorting on the messages endpoints
• Logging
• Prometheus metrics

To build a docker image: ./mvnw spring-boot:build-image