# Simple calculator

This calculator project contains a simple Angular based frontend a Spring based backend.

## Environment

To compile and run this project the following software needs to be installed and available on the
path. Versions used for development are listed.

- Maven (3.6.3)
- Java JDK (OpenJDK 11.0.9.1)
- NPM (7.1.0)
- Node.js (v12.19.0)
- Angular (11.0.3)
 
## Backend

To (somewhat) stay in line with RESTful principles, the backend api models a number as a resource 
on which calculations can be applied. This makes it possible to avoid hardcoding arithmetic 
operations in the frontend and use HATEOAS links instead. The latter is not implemented. 

### Compiling and running

Navigate into the `backend` directory and run `mvn spring-boot:run`

### Example api call

Navigate to `http://localhost:8080/numbers/5/add/15` in a browser and observe the response.

## Frontend

### Compiling and running

Navigate to the `frontend` directory and run `ng serve`
To access the UI navigate to `http://localhost:4200/` with a browser.