Exercise

• Develop a 3-Tier application to capture the user coins in the system.

• The Frontend can be either Angular or React.

• The Backend should be Springboot.

• The Database is preferably H2 or any other database storage.

Requirements

• Consider the App will be used by the admin user. (But, there is no authentication/authorization for the exercise)

• Admin can submit coins for a given user. (The user name is free text)

• The name should have minimum length validation of 3 characters.

• The coin is numeric and should be greater than zero.

• The user's coins should be stored in the database table in the append-only approach.

  Example :

  id	Name	Coin
  1	Jai	50
  2	Rai	70
  3	Jai	100
  4	Rai	30

• The summary table in UI aggregate results by user name

  Example :

  Name	Coin
  Jai	150
  Rai	100

• The summary table should be implemented by reactive rendering. (Either using API polling or observable or WebSocket)

• The summary table should render data submitted from different browser/tabs.

Front End : React/Angular

The User interface can be designed similar to the below image. (Theming is not mandatory)

• An Entry form to submit coins for a given user.

• A summary table to display cumulative user coins.

Back End : Spring Boot

Create two rest endpoints as shown below

API to persist user coins

POST 
    http://localhost:8080/api/coin

Request Body :
    {
        "name": "jai",
        "coin": 50
    }
Response : 201 Success
    {
        "message": "Added 50 coins to 'jai'"
    }

API to retrieve cumulative user coins

GET 
    http://localhost:8080/api/coins

Response : 
    [
       {
            "name": "jai",
            "coin": 100
        },
        {
            "name": "rai",
            "coin": 75
        }
    ]