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Streaming & messaging

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

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Streaming & messaging easy

How to Mock MQTT Topic Subscriptions with QoS in Python

Build a lightweight MQTT client mock that tracks topic subscriptions with QoS levels and simulates wildcard message delivery.

mqtt mock qos
Python 
import time
from collections import defaultdict

class MockMQTTClient:
    def __init__(self):
        self.subscriptions = defaultdict(list)
        self.messages = []
    
    def subscribe(self, topic, qos=0):
        self.subscriptions[topic].append(qos)
        print(f"Subscribed to '{topic}' with QoS {qos}")
   …
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