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System design patterns

Sharding, load balancing, CAP tradeoffs, and scaling patterns — interview and production ready.

2 matches
System design patterns medium

Facade Pattern in Python with Mock Simplification

This code demonstrates the Facade pattern by hiding complex subsystem interactions behind a simple start/stop interface, and adds a MockFacade for testing failure scenarios.

facade-pattern design-patterns abstraction
Python
class SubsystemA:
    def operation_a(self):
        return "Subsystem A: ready"

class SubsystemB:
    def operation_b(self):
        return "Subsystem B: ready"

class SubsystemC:
    def operation_c(self):
        return "Subsystem C: ready"


class Facade:
    def __init__(self):
        self._a = SubsystemA()
   …
17 0 Open
System design patterns medium

How to Implement the Abstract Factory Pattern in Python

Implements the Abstract Factory pattern to create families of related GUI objects (buttons, checkboxes) without specifying their concrete classes.

abstract-factory design-patterns system-design
Python
from abc import ABC, abstractmethod


class Button(ABC):
    @abstractmethod
    def render(self):
        pass


class Checkbox(ABC):
    @abstractmethod
    def render(self):
        pass


class WindowsButton(Button):
    def render(self):
        return "Rendering Windows-style button"


class WindowsCheckbox(Chec…
13 0 Open

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System design patterns — Python code examples

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