Reference library

Streaming & messaging

Kafka-style pub/sub, event consumers, async pipelines, and message-driven workflows.

2 matches

How to Implement an In-Memory Pub/Sub System in Python

This code implements a simple in-memory publish/subscribe system in Python, allowing topics, callbacks, and message broadcasting.

pubsub event-driven design-pattern

Python

class PubSub:
    def __init__(self):
        self.topics = {}

    def subscribe(self, topic, callback):
        if topic not in self.topics:
            self.topics[topic] = []
        self.topics[topic].append(callback)
        return lambda: self.unsubscribe(topic, callback)

    def unsubscribe(self, topic, callb…

18 0 Open

Streaming & messaging medium

Implement the Transactional Outbox Pattern with SQLite in Python

A Python implementation of the transactional outbox pattern using SQLite, ensuring atomic writes of order data and outbox events in a single transaction while supporting reliable message publishing and consumption.

outbox-pattern sqlite transactions

Python

import sqlite3
from dataclasses import dataclass
from datetime import datetime, timezone
import json

@dataclass
class Order:
    order_id: str
    amount: float
    status: str

class TransactionalOutbox:
    def __init__(self, db_path=":memory:"):
        self.conn = sqlite3.connect(db_path)
        self._create_tab…

17 0 Open

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