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Python Code Samples

Medium snippets you can copy, study, and run in the browser editor.

27 matches
Database scaling & optimization medium

How to Simulate Distributed Transactions in Python with a Mock

Model distributed transaction behavior with a mock Transaction class that supports commit, rollback, and failure simulation.

transactions mock database
Python 
class Transaction:
    def __init__(self, id):
        self.id = id
        self.operations = []
        self.committed = False

    def add_operation(self, op, data):
        self.operations.append((op, data))

    def commit(self):
        if not self.operations:
            raise ValueError("No operations to commit…
13 0 Open
Database scaling & optimization medium

Mock CQRS Read/Write Split in Python

Separate order mutations from queries using a read model and write model to mock CQRS-style separation of concerns.

cqrs read-write dataclass
Python 
from dataclasses import dataclass, field
from typing import List, Dict


@dataclass
class Order:
    id: int
    amount: float
    status: str = "pending"


class OrderWriteModel:
    """Handles all mutations (writes) to orders."""

    def __init__(self):
        self._orders: Dict[int, Order] = {}
        self._next…
12 0 Open
Production deployment patterns medium

How to Mock Image Signing Cost in Python

Create a deterministic mock signing cost calculator that predicts resource usage for image signatures before real signing infrastructure is staged.

mock signing cost-model
Python 
import math
import struct


def sign_image_cost(image_signature: bytes) -> int:
    """Deterministic mock signing cost based on image signature bytes."""
    if not image_signature:
        raise ValueError("Empty image signature")
    digest = 0
    for byte in image_signature:
        digest = (digest * 31 + byte) &…
14 0 Open

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