USERLY

A spring boot application for tracking user views

H2 is used for storage

How tos

make sure java 15 and maven are installed.
use ./mvnw spring-boot:run to run project.
you can reach swagger documentation from http://localhost:8080/swagger-ui.html

Application Designs

NOT include more than 20 items; Pagination used for keeping user view list size at 20 for every response
NOT include views older than 30 days; This is achieved by asynchronously check the oldest records time and if it is expired delete all expired records

User Entity

id	name
Long	String

id is primary key keeps registered users.

UserView Entity

id	viewer_id	viewed_id	viewed_at
Long	Long	Long	Long

id is the primary key keeping order for creation.

High Load Assumption

In the case of a high load for this project, I would split the stateless part which is saving and fetching views and stateful part which always keeps database cleaned via running periodically. This way I could scale stateful and stateless parts of my app individually.

Questions

Do you delete any data from the database? Answer: Yes, because data older than 30 days are unused and needs to be clean
Do you have any periodic task type of batch jobs to maintain data? Answer: No, because I cleaned database by caching the oldest value and if it is old enough I remove old data asynchronously on user view creation

Hamzali / userly