coupon-api

This API returns a list of items that can be bought with a coupon, without exceeding its amount.

Knapsack problem

The knapsack problem is a problem in combinatorial optimization: Given a set of items, each with a weight and a value, determine the number of each item to include in a collection so that the total weight is less than or equal to a given limit and the total value is as large as possible. It derives its name from the problem faced by someone who is constrained by a fixed-size knapsack and must fill it with the most valuable items. Wikipedia

The API premise is based on the knapsack problem but with a little twist: instead of take care of the value and weight, we have to worry about the item prices and also return the selected items.

Usage

Build the artifact and docker image run:

mvn clean install

Build a runnable java artifact without creating a docker image

mvn clean package

Run docker image

docker run stefy421/coupon-api

Generalities

The project includes:

• Java documentation into PROJECT_ROOT_PATH/javadoc.
• Swagger documentation http://localhost:8080/swagger-ui/
• Actuator for checking health of application http://localhost:8080/actuator/health

API Request

local: http://localhost:8080/coupon/

AWS: http://ec2-18-212-190-42.compute-1.amazonaws.com:8888/coupon/

Body application/json

{
    "item_ids":["MCO569635558",
                "MCO613591599",
                "MCO593323015",
                "MCO596414800",
                "MCO564169608",
                "MCO453857398"],
    "amount": 200000
}

API response

Body application/json

{
    "item_ids": [
        "MCO453857398",
        "MCO593323015",
        "MCO613591599"
    ],
    "total": 198700.0
}

When the coupon amount sent is not enough to buy at least one item, the API reponse with 404 - NOT FOUND