✔️ Use migration tool for DB migration on app startup. Note: Used Flyway
✔️ Use localization for exception messages with support for English(default) and Japanese. Note: Present in config/LocalizationConfig.java. Japanese resources prefixed with JA to signify Japanese. Use Accept-Language header as ja to change language
✔️ A Book will only have a BookMeta(1-1).
✔️ Send an email notification to user when a book is issued(Mock the email sending part). Note: Mocked in a Kafka consumer
✔️ In API requests/responses send dates as DD-MM-YYYY and save as YYYY-MM-DD format in the database. Request/Response body will be in snake_case and in Java side use camelCase. Note: Config in application.properties
✔️ Handle common exceptions(400, 404) cases using global configuration. Note: Config in config/GlobalExceptionHandlerConfig.java
✔️ Configure Tomcat to have 300 threads simultaneously. Note: Config in application.properties
✔️ Dockerize the application.
✔️ Use Github actions to build the project and run tests(don’t need extensive test coverage, just writing a few for this purpose is okay).
Extra:
Created docker-compose file for ease of deployment
Back-end Design decisions
API-s are designed based on resources.
Preffering Pessimistic Locking over Optimistic Locking when updating resources.
Book borrow and submit are intentionally kept accessible by any authenticated user, even though the spec says only USER role can access GET requests.
Proposed Improvements
Add Swagger documentation
Redis cache
Add load tests and concurrent update checks
At this moment only bean validation uses localization messages. 404, 500 etc errors don't show localized messages
