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Microservices patterns

Service boundaries, discovery, inter-service calls, and decomposition patterns.

3 matches

How to Implement an Exactly-Once Deduplication Store in Python

Implement a Python class that deduplicates keys exactly once, tracking first-seen timestamps and duplicate counts.

from datetime import datetime
from typing import Any, Hashable


class ExactlyOnceStore:
    def __init__(self) -> None:
        self._seen: set[Hashable] = set()
        self._first_seen: dict[Hashable, datetime] = {}
        self._counts: dict[Hashable, int] = {}

    def add(self, key: Hashable, value: Any = None) …

13 0 Open

Microservices patterns easy

Retry idempotent GET requests in Python

A Python function that retries an idempotent GET request a fixed number of times with a delay between attempts, raising a RuntimeError only after all retries fail.

retry idempotent urllib

Python

import time
import urllib.error
import urllib.request
from http.client import HTTPException

def fetch_with_retry(url, max_retries=3, delay=1.0):
    for attempt in range(1, max_retries + 1):
        try:
            with urllib.request.urlopen(url, timeout=5) as response:
                return response.read().decode…

14 0 Open

Microservices patterns easy

Strangler Fig Migration Pattern in Python

Gradually reroute calls from a legacy service to a modern replacement using a runtime switch and feature detection.

migration facade microservices

Python

from dataclasses import dataclass

@dataclass
class PaymentService:
    def process(self, amount: float) -> str:
        return f"Legacy processed ${amount:.2f}"

class StranglerFig:
    def __init__(self):
        self._new_service = None

    def attach_new(self, service):
        self._new_service = service

    de…

14 0 Open

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