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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

5 matches
System design patterns medium

How to implement saga orchestration with compensating steps in Python

Orchestrate a distributed transaction across services, rolling back completed steps with compensations when a later step fails.

saga distributed-transactions compensation
Python
class InventoryService:
    def reserve(self, order_id):
        print(f"[Inventory] Reserving stock for order {order_id}")
        return True

    def compensate(self, order_id):
        print(f"[Inventory] Releasing stock for order {order_id}")


class PaymentService:
    def charge(self, order_id):
        print(f…
14 0 Open
Reliability & rate limiting medium

Saga Compensating Transaction Mock in Python

Simulates a distributed transaction using a saga pattern with compensating actions that roll back steps on failure.

saga transaction compensation
Python
import random
import time


class OrderService:
    def __init__(self):
        self.orders = {}

    def create_order(self, order_id):
        print(f"[Order] Creating order {order_id}...")
        time.sleep(0.1)
        if random.random() < 0.3:  # 30% chance of failure
            raise RuntimeError(f"Order {order…
12 0 Open
Microservices patterns medium

Python Saga Compensating Steps Mock

Mock a distributed transaction saga with forward steps and compensating actions that reverse partial progress on failure.

saga microservices compensation
Python
from datetime import datetime


def make_payment(user_id, amount):
    print(f"[{datetime.now():%H:%M:%S}] Payment of ${amount} processed for user {user_id}")
    return {"step": "payment", "status": "ok", "details": f"${amount} charged"}


def deduct_inventory(order_id, items):
    print(f"[{datetime.now():%H:%M:%S}]…
14 0 Open
Microservices patterns medium

Saga pattern orchestration with rollback in Python

Orchestrate a distributed transaction with Saga steps and automated compensation rollback on failure.

saga microservices transaction
Python
import time
import random


class SagaStep:
    def __init__(self, name):
        self.name = name
        self.executed = False

    def execute(self):
        print(f"Executing {self.name}...")
        time.sleep(0.2)
        if random.random() < 0.3:
            raise RuntimeError(f"{self.name} failed")
        sel…
14 0 Open
Database scaling & optimization medium

How to Mock a Cross-Shard Saga in Python

Simulate a distributed saga with compensating transactions across multiple database shards using a lightweight Python class that tracks executed steps and rolls them back in reverse on failure.

saga sharding distributed-systems
Python
import json


class SagaState:
    def __init__(self, saga_id):
        self.saga_id = saga_id
        self.executed_steps = []
        self.compensations = []

    def execute_step(self, shard, step_name, operation):
        self.executed_steps.append((shard, step_name))
        print(f"[Saga {self.saga_id}] Executin…
14 0 Open

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