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Production deployment patterns

Graceful shutdown, prod config, rollouts, readiness probes, and ship-with-confidence checks.

3 matches

How to Expand a Contract and Migrate Data in Python

Expand an old data contract by renaming fields and adding defaults, then migrate to a final version with deepcopy isolation.

contract migration deepcopy

Python

import json
from copy import deepcopy

# Mock data representing a user record (old contract)
old_contract = {
    "id": 1,
    "name": "Alice",
    "email": "alice@example.com",
    "age": 30,
    "status": "active"
}

# Expanded contract: adds fields with defaults and renames some fields
expand_rules = {
    "id": "u…

14 0 Open

Production deployment patterns easy

How to Mock Multi-Stage Docker Builds in Python

Simulate a multi-stage Docker build in pure Python using classes and temp directories to understand how build stages copy artifacts into a final image.

docker multi-stage simulation

Python

# Simulate multi-stage Docker build with pure Python
from pathlib import Path
import tempfile
import shutil

class BuildContext:
    """Mimics a Docker build context with stages."""
    
    def __init__(self, name):
        self.name = name
        self.files = {}
    
    def add_file(self, dest, content):
        s…

14 0 Open

Production deployment patterns easy

How to Replace Fields in an Immutable Dataclass in Python

Create a new copy of a frozen dataclass with selected fields changed, leaving the original unchanged.

dataclasses immutable configuration

Python

from dataclasses import dataclass, replace


@dataclass(frozen=True)
class ServerConfig:
    name: str
    cpu: int = 2
    ram: int = 4096
    tags: tuple = ()


original = ServerConfig("web-01", cpu=4, tags=("env:prod",))
updated = replace(original, ram=8192, tags=("env:prod", "region:us-east"))

print("Original:", …

15 0 Open

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