Streaming & messaging
Kafka-style pub/sub, event consumers, async pipelines, and message-driven workflows.
How to Mock NATS Subject Hierarchies with Wildcards in Python
Build a lightweight NATS-style pub/sub mock that matches subject hierarchies with '*' and '>' wildcards for tests or prototypes.
# Mock a simplified NATS subject hierarchy with wildcard matching
# Supports: exact match, '*' (single token), '>' (tail wildcard)
class NATSSubjectMock:
def __init__(self):
self.subscriptions = {} # subject -> list of callbacks
def subscribe(self, subject, callback):
self.subscriptions.setd…Mock NATS queue group load balancing in Python
Simulates a NATS queue group where each message is delivered to exactly one subscriber using random selection with a lightweight mock.
import random
import time
from collections import defaultdict
class MockQueueGroup:
"""Mock a NATS queue group: each message is delivered to exactly one subscriber."""
def __init__(self, subscribers):
self.subscribers = subscribers
def publish(self, message):
receiver = random.choice(se…Browse by section
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Streaming & messaging — Python code examples
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