Links: PYTHON
Rel:
Ref: https://pydantic-docs.helpmanual.io/; https://docs.python.org/3/library/typing.html
Tags: #public

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from pydantic import BaseModel

type-validation & automatic cleaning:

import datetime
from typing import List, Optional

from pydantic import BaseModel

order_json = {
    'item_id': '123',
    'created_date': '2002-11-24 12:22',
    'pages_visited': [1, 2, '3'],
    'price': 17.22
}


class Order(BaseModel):
    item_id: int
    created_date: Optional[datetime.datetime] #optional 
    pages_visited: List[int] = [] #give default
    price: float


o = Order(**order_json)
print(o)

versus something like:

class Order:

    def __init__(self, item_id: int, created_date: datetime.datetime, price: float, pages_visited=None):
        if pages_visited is None:
            pages_visited = []

        try:
            self.item_id = int(item_id)
        except ValueError:
            raise Exception("Invalid item_id, it must be an integer.")

        try:
            self.created_date = parse(created_date)
        except:
            raise Exception("Invalid created_date, it must be an datetime.")

        try:
            self.price = float(price)
        except ValueError:
            raise Exception("Invalid price, it must be an float.")

        try:
            self.pages_visited = [int(p) for p in pages_visited]
        except:
            raise Exception("Invalid page list, it must be iterable and contain only integers.")

    def __str__(self):
        return f'item_id={self.item_id}, created_date={repr(self.created_date)}, ' \
               f'price={self.price}, pages_visited={self.pages_visited}'

    def __eq__(self, other):
        return isinstance(other, Order) and self.__dict__ == other.__dict__

    def __ne__(self, other):
        return isinstance(other, Order) and self.__dict__ == other.__dict__


o = Order(**order_json)
print(o)

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