Prime Checker

Simple tool to check if a given number is prime or not. It includes a ReactJS frontend and a Spring Boot Java backend.

Structure

/backend contains all the code related to Spring Boot for the backend /frontend contains all the code related to ReactJS for the frontend

Running the project

Backend

1. Go the the /backend folder.
2. On macOS, run ./mvnw spring-boot:run.
3. The server is now running on http://localhost:8080 and accepts POST requests here http://localhost:8080/checker.

Frontend

1. Go the the /frontend folder.
2. On macOS, run npm run start.
3. The frontend is now accessible here http://localhost:3000.
4. Some browser including Google Chrome will prompt an error when submitting the form asking for the Access-Control-Allow-Headers header. A quick fix is to run open /Applications/Google\ Chrome.app --args --user-data-dir="/var/tmp/Chrome dev session" --disable-web-security on macOS.

Possible improvements

• From validation is weak. We should check that the given numbers are not too large or too small in both front and backend.
• We should use a captcha or at least a honeypot to avoid basic attacks.
• We should use CSRF Tokens to avoid Cross-Site Reference Forgery.
• It would be great to check if the backend code follows the good practices recommended by the Spring Boot community.
• ReactJS code should be refactored, tested, and documented.
• Axios error handling is weak and should be improved.
• The UI/UX is basic; the user experience could largely be improved.

Credits

Timothée Duran