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Microservices patterns

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

5 matches

Fallback cached response mock in Python

Wraps a mock function with a fallback to a real service and caches results to mask transient failures.

import time
from functools import wraps

class CachedMock:
    def __init__(self, cache_ttl=5):
        self.cache = {}
        self.cache_ttl = cache_ttl

    def get(self, key):
        cached = self.cache.get(key)
        if cached and time.time() - cached["timestamp"] < self.cache_ttl:
            return cached["v…

14 0 Open

Microservices patterns easy

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.

deduplication exactly-once set

Python

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

Mock a Sidecar Logger with Python Metrics

Simulate a sidecar logger that tracks request counts, error rates, and endpoint hits, producing a metrics snapshot.

microservices monitoring metrics

Python

import random
import time
from collections import defaultdict


class SidecarLogger:
    def __init__(self):
        self.metrics = defaultdict(int)
        self.total_requests = 0
        self.error_count = 0

    def log_request(self, endpoint, status_code):
        """Simulate logging a request and updating metrics…

16 0 Open

Microservices patterns medium

Python Saga Compensating Steps Mock

Mock a distributed transaction saga with forward steps and compensating actions that reverse partial progress on failure.

saga microservices compensation

Python

from datetime import datetime


def make_payment(user_id, amount):
    print(f"[{datetime.now():%H:%M:%S}] Payment of ${amount} processed for user {user_id}")
    return {"step": "payment", "status": "ok", "details": f"${amount} charged"}


def deduct_inventory(order_id, items):
    print(f"[{datetime.now():%H:%M:%S}]…

14 0 Open

Microservices patterns medium

Saga pattern orchestration with rollback in Python

Orchestrate a distributed transaction with Saga steps and automated compensation rollback on failure.

saga microservices transaction

Python

import time
import random


class SagaStep:
    def __init__(self, name):
        self.name = name
        self.executed = False

    def execute(self):
        print(f"Executing {self.name}...")
        time.sleep(0.2)
        if random.random() < 0.3:
            raise RuntimeError(f"{self.name} failed")
        sel…

14 0 Open

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