Orange Sky Exercise

Setup

There are two option for launching the application:

• execute php -S 127.0.0.1:8080 ./public/built-in.php from terminal (will need PHP installed locally)
• execute make deploy to run in docker (will require docker service running)

The actual entry point for the API code is /public/api.php (which is what one would be set in the Nginx url.rewrite), but in the "launch-able" options it gets called via built-in.php file, that acts as "rewriter" for PHP's bundled server.

Requirements

Design, develop & test full-stack web application.

Functional requirements :

• Calculator with 4 functions (add, sub, div, mul)
• Ability to store/retrieve 5 last calculation results 

Non-functional requirements :

• Frontend : XHTML/JS (any framework), CSS (Sass/Less)
• Backend : PHP (any framework)
• DB : any (sql/nosql)
• API : REST
• Unit tests : PHP (any framework)
• Build tool : frontend - any, backend - any/framework specific
• Container : Docker
• Source control : Git (GitHub)

Bonus points :

• Clean code approach used
• Design patterns applied
• S.O.L.I.D principles demonstrated
• PSR standards observed

Application should run as single Docker container with all dependencies configured & bundled together, exposed on localhost:8080.
Application should support running under profiles : "dev" (default) for local environments, "prod" for production deployments.