README.md

CLEVERTEC TEST TASK 🌐

1 Technologies

• Spring Boot, Java
• PosrgreSQL
• Docker

2 How to start application?

1. Clone this repository

2.  cd ${project_folder}
   

3. ./gradlew clean build
   

4.  docker-compose up
   

3 Endpoints

3.1 Products

Method	URL	Description	Status	Response Type	Params by default
GET	/products	Get list of products by page and size params	200	Application/JSON	page=0, size=5
GET	/products/{id}	Get product by id param	200	Application/JSON	-
POST	/products	Add new product	201	Application/JSON	-
PUT	/products/{id}	Update product	204	Application/JSON	-
DELETE	/products/{id}	Delete product	204	-	-

3.1.1 Add new product

Request body:

    {
        "name": "name",
        "price": 123.21,
        "promotional": true
    }

Response:

    {
        "id": 1
        "name": "name",
        "price": 123.21,
        "promotional": true
    }

3.1.2 Update product

Request Body:

    {
        "id": 1,
        "name": "name-1",
        "price": 1251.21,
        "promotional": false
    }

Response: 204 NO_CONTENT

3.2 Discount cards

Method	URL	Description	Status	Response Type	Params by default
GET	/discountCards	Get list of discount cards by page and size params	200	Application/JSON	page=0, size=5
GET	/discountCards/{id}	Get discount card by id param	200	Application/JSON	-
POST	/discountCards	Add new discount card	201	Application/JSON	-

3.2.1 Add new discount card

Request body:

    {
        "discount": 20
    }

Response:

    {
        "id": 1
        "discount": 20
    }

3.2.1 Update discount card

Request body:

    {
        "id": 1
        "discount": 35
    }

Response: 204 NO CONTENT

3.3 Checks

Method	URL	Description	Status	Response Type	Params by default
GET	/checks	Get list of checks by page and size params	200	Application/JSON	page=0, size=5
GET	/checks/{id}	Get check by id	200	Application/JSON	-
GET	/checks/export/{id}	Download check by id in PDF	200	Application/PDF	-
POST	/checks	Create new check	201	Application/JSON	-
DELETE	/checks/{id}	Delete check by id	204	-	-

3.3.1 Generate new check

Request body:

    {
        "items": 
        [
            {
                "productId": 1,
                "quantity": 2
            },
            {
                "productId": 2,
                "quantity": 3
            },
            {
                "productId": 3,
                "quantity": 4
            }
        ]
        "discountCardId": 3
    }

Response:

    {
        "checkId": 1
        "items": 
        [
            {
                "id": 1, 
                "product":
                {
                    "id": 1,
                    "name": "name-1"
                    "price": 200.00,
                    "promotional": false,
                },
                "quantity": 2, 
                "totalPrice": 400.00
            },
            {
                "id": 2, 
                "product":
                {
                    "id": 1,
                    "name": "name-2"
                    "price": 200.00,
                    "promotional": false,
                },
                "quantity": 3, 
                "totalPrice": 600.00
            },
            {
                "id": 3, 
                "product":
                {
                    "id": 3,
                    "name": "name-3"
                    "price": 200.00,
                    "promotional": false,
                },
                "quantity": 4, 
                "totalPrice": 800.00
            }
        ],
        "discountCard": 
        {
            "id": 3,
            "discount": 20
        },
        "totalPrice": 1440,
        "createdAt": "2022-12-21T18:18:36.165+00:00"
    }

3.3.2 Check export

4 Database structure

    create table _check (
        id               bigserial      not null,
        created_at       timestamp(6)   not null,
        total_price      numeric(38, 2) not null,
        discount_card_id bigint,
        primary key (id)
    );

    create table discount_card (
        id       bigserial not null,
        discount integer   not null,
        primary key (id)
    );

    create table position (
        id          bigserial      not null,
        quantity    integer        not null,
        total_price numeric(38, 2) not null,
        check_id    bigint,
        product_id  bigint         not null,
        primary key (id)
    );

    create table product (
        id          bigserial      not null,
        name        varchar(255)   not null,
        price       numeric(40, 2) not null,
        promotional boolean        not null,
        primary key (id)
    );

    alter table if exists _check
        add constraint fk_discount_card_id
        foreign key (discount_card_id)
        references discount_card;

    alter table if exists position
        add constraint fk_check_id
        foreign key (check_id)
        references _check;

    alter table if exists position
        add constraint fk_product_id
        foreign key (product_id)
        references product;

5. Caching

In this project, caching is implemented using a custom in-memory cache using LRU and LFU algorithms.

Caches are represented by two classes: LFUCache and LRUCache.

Both classes implement the Cache<K, V> interface, where K is a typed parameter for the cache entry key, and V is the value of the cache entry.

Each cache has three methods:

•    boolean put(K key, V value)
  

•    Optional<V> get(K key)
  

•    boolean remove(K key)
  

More information about cache methods can be found in the javadoc of the Cache<K, V> interface.

Cache replacement policies - Wikipedia