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Microservices patterns

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

3 matches

Cache-Aside Pattern in Python: Per-Service Mock

A Python mock of the cache-aside pattern for a single microservice—lazy-load from a database into an in-memory cache and invalidate on updates.

caching microservices cache-aside

Python

class ServiceCache:
    def __init__(self):
        self.database = {"user:1": "Alice", "user:2": "Bob", "user:3": "Charlie"}
        self.cache = {}

    def get_user(self, user_id):
        cache_key = f"user:{user_id}"
        if cache_key in self.cache:
            print(f"CACHE HIT: {cache_key}")
            retu…

13 0 Open

Microservices patterns easy

How to Demonstrate the Shared Database Antipattern in Python

This code simulates a shared database where multiple services write and read the same SQLite table, illustrating tight coupling and its pitfalls.

microservices database antipatterns

Python

import sqlite3
from pathlib import Path

def create_shared_db(db_path: Path) -> None:
    """Mock demonstrating the shared database antipattern where multiple
    services access the same database, causing tight coupling."""
    conn = sqlite3.connect(db_path)
    cur = conn.cursor()
    cur.execute("""
        CREATE…

13 0 Open

Microservices patterns medium

How to implement the Database per service pattern in Python

Simulate separate databases per microservice in Python using dataclasses and in-memory dictionaries, showing how services own their data independently.

microservices database-per-service dataclasses

Python

import json
from dataclasses import dataclass, asdict
from typing import Dict, List


@dataclass
class User:
    id: int
    name: str
    email: str


@dataclass
class Order:
    id: int
    user_id: int
    product: str
    amount: float


class UserServiceDB:
    """Simulates a separate database for the User servic…

12 0 Open

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