codesnips

discounts

python 
from __future__ import annotations

from dataclasses import dataclass, field
from decimal import Decimal, ROUND_HALF_UP
from typing import Optional, Protocol

Composable Order Discount Pipeline With Rule Objects in Python

pipeline strategy-pattern discounts
by codesnips 3 tabs
ruby 
class DiscountCode < ApplicationRecord
  has_many :redemptions, dependent: :destroy

  enum discount_type: { percentage: 0, fixed: 1 }

  validates :code, presence: true, uniqueness: { case_sensitive: false }

Redeem Discount Codes in Rails with a Locking Service and Row-Level Guards

rails activerecord discounts
by codesnips 4 tabs
typescript 
export interface CartItem {
  sku: string;
  name: string;
  unitPrice: number; // cents
  qty: number;
}

Shopping Cart Pricing with a useReducer State Machine and a Pure Discount Engine

react usereducer typescript
by codesnips 3 tabs