Reference library

Streaming & messaging

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

3 matches

How to Stream Join Windowed Mock Topics in Python

Simulates two message topics and joins their events when timestamps fall within a sliding time window using Python generators and deques.

streaming join generator

Python

import itertools
import random
import time
from collections import deque
from dataclasses import dataclass, field

@dataclass
class Event:
    key: str
    value: int
    timestamp: float = field(default_factory=time.time)

def generate_topic(prefix, keys, start_time):
    while True:
        yield Event(
            …

14 0 Open

Streaming & messaging medium

In-Memory PubSub Topic Subscribe Mock in Python

Build a thread-safe in-memory publish/subscribe mock where handlers subscribe to named topics and receive every message published to them.

pubsub mock events

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)

    def publish(self, topic, message):
        for callback in self.topics.get(topic, []):
    …

16 0 Open

Streaming & messaging medium

Simulate RabbitMQ QoS Prefetch Count in Python

Mocks RabbitMQ QoS prefetch semantics using threading and a queue to cap concurrent unacked message processing per worker.

rabbitmq threading qos

Python

import threading
import time
import queue


class RabbitMQMock:
    def __init__(self, prefetch_count=1):
        self.prefetch_count = prefetch_count
        self.channel_queue = queue.Queue()
        self.currently_processing = 0
        self.lock = threading.Lock()

    def start_consuming(self, messages, worker_co…

13 0 Open

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