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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 simulate a database migration init container mock in Python

A mock init container that runs environment checks and a staged database migration job before the main application starts, printing progress to stdout.

init-container migration simulation

Python

```python
class MigrationJob:
    def __init__(self, name, steps):
        self.name = name
        self.steps = steps
        self.current_step = 0
        self.status = "pending"

    def run(self):
        print(f"Initializing migration job: {self.name}")
        for step in self.steps:
            self.current_ste…

15 0 Open

Production deployment patterns medium

Zero Downtime Migration with Dual Write Pattern in Python

Implement a dual-write pattern that writes user data to both legacy and new systems simultaneously to enable zero-downtime migration.

migration dual-write zero-downtime

Python

from datetime import datetime
import json


class UserService:
    def __init__(self):
        self.legacy_db = {}
        self.new_db = {}
        self.migration_log = []

    def write_user(self, user_id, name, email):
        # Write to new system first
        user_record = {
            "id": user_id,
           …

13 0 Open

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