To solve the problem of ConsumerStore I chosed to built some structure in terms of project, like:

README.md (this file)
-- dev
   -- src
        test.py
        -- enums
            enums.py
        -- types
            product.py
            store.py

Each of these files represents part of the solution to isolate responsabilities, according to POO.

The execute only requeres python version 3.8+, which this activity has been built in.

To declare new objects, there is some important informations we need to fill.

To declare a product:

# Import types and enums
from src.types import product, store
from src.enums import enums

# Create each one of the objects
stv = product.Product(id="stv",
                     name="Sony TV",
                     price=549.99)

Where the id of product is unique, so the another Sony TVs might have the same id. The name and price are necessary to creation of this object.

To declare a new rule:

# Create pricing rules
pricing_rule_1 = {
                     "id": "nsh",
                     "buy": 3,
                     "gain": 2,
                     "condition": ">=",
                     "discount_value": 100.000,
                     "discount_type": enums.DiscountType.BUY_WIN,
                     "gift": None
                 }

This structure is very important to make rules available in ConsumerStore. The id represents the id of product. The rule will be aplied for the group of products which has the same id.

The buy variable represents the value of items that has been necessary to reach.

The gain represents how many items could be gained based on buy.

The condition represents which condition has to be satisfied to make the pricing rule real. We can see it in table 02.

The discount_value is a value in percentage in the interval of 0 to 100. The decimal houses has to be precised with more than 2.

The discount_type is a enumerate typo to help to filter which type of discount we are applying on. If we want to make roles like "Buy 3 and Win 2", we have to choose BUY_WIN. If our goal is just to apply a significant discount value, we use PRICE_REDUCTION.

Last, but not least, the gift fields represents what this offer should retrieve as a gift.

To illustrate that, let's explore the rule 01.

"1. We have a 3 for 2 great deal on Nike Shoes. i.e. if you buy 3 Nike Shoes, you’ll just pay the price of 2."

So, our buy value has to be 3, because the consumer has to buy at least 3 pairs of Nike Shoes. Our gain will be 2, because we are only going to pay for two pairs of Nike Shoes. To satisfy our condition, our condition field has to be >=, because we want to have more or equal 3. Our discount_value will be 100, because we win 1 pair of Nike Shoes in this rule. To our discount_type, it is a BUY_WIN rule. To the gift field we have nothing, because there is no gift of this rule.

The whole info about how does variables works are also located in the code for each of the classes.

The table with condition operators is on table 02, on next:

Note that I use the same logical operators that Python language uses.

To declare a consumer store:

co = store.ConsumerStore(pricing_rules=pricing_rules)

Where the pricing_rules can be represented as pricing_rule_1.

To execute the tests of the exercise goes to /dev/src/ and runs:

python test.py

The results will be shown on python console. Showing the Total, which is calculates by the program, and the expected value from the exercise.

30/03/2021

author: Walacy da Silva Campos
email: [email protected]