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Python Code Samples

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3 matches
Streaming & messaging easy

How to Implement Publish-Subscribe Fanout with Multiple Subscribers in Python

Create a simple publish-subscribe system in Python that broadcasts messages to multiple subscriber callbacks for a given topic.

pubsub messaging events
Python
import time

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

    def subscribe(self, topic, callback):
        if topic not in self.subscribers:
            self.subscribers[topic] = []
        self.subscribers[topic].append(callback)

    def publish(self, topic, message):
        if topic in sel…
14 0 Open
Streaming & messaging easy

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 easy

Redis Pub/Sub Channel Subscribe Mock in Python

A lightweight in-memory mock of Redis pub/sub that lets you subscribe to channels, publish messages, and verify handler behavior in tests without a real Redis server.

redis pubsub testing
Python
class MockRedisPubSub:
    def __init__(self):
        self.channels = {}

    def subscribe(self, channel):
        if channel not in self.channels:
            self.channels[channel] = []
        return self.channels[channel]

    def publish(self, channel, message):
        if channel in self.channels:
            …
11 0 Open

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