greenjune-ship-it/python-design-patterns

Basics Patterns implemented in Python

Python: Design Patterns

This repository contains learning notes about ready-to-use patterns examples written in Python

List of Content

Creatinal Patterns:

• factory.py method pattern is a creational pattern that uses factory methods to deal with the problem of creating objects without having to specify the exact class of the object that will be created
• abstract-factory.py design pattern is interface to create families of related objects without specifying their concrete classes
• singleton.py this pattern involves a single class which is responsible to create an object while making sure that only single object gets created
• builder_animals.py, builder_cars.py the intent of the builder design pattern is to separate the construction of a complex object from its representation
• prototype.py is used when the type of objects to create is determined by a prototypical instance, which is cloned to produce new objects

Structural Patterns

• decorator.py pattern allows a user to add new functionality to an existing object without altering its structure
• proxy.py pattern allows to create a class that represents functionality of another class (the object having original object to interface its functionality to outer world)
• adapter.py pattern is a software design pattern (also known as wrapper, an alternative naming shared with the decorator pattern) that allows the interface of an existing class to be used as another interface
• composite.py pattern describes a group of objects that are treated the same way as a single instance of the same type of object
• bridge.py pattern involves an interface which acts as a bridge which makes the functionality of concrete classes independent from interface implementer classes

Behavioral Patterns

• observer.py is a software design pattern in which an object, named the subject, maintains a list of its dependents, called observers, and notifies them automatically of any state changes, usually by calling one of their methods
• visitor.py design pattern is a way of separating an algorithm from an object structure on which it operates. A practical result of this separation is the ability to add new operations to existing object structures without modifying the structures
• iterator.py is used to traverse a container and access the container's elements
• strategy.py enables selecting an algorithm at runtime. Instead of implementing a single algorithm directly, code receives run-time instructions as to which in a family of algorithms to use
• chain.py pattern is recommended when multiple objects can handle a request and the handler doesn't have to be a specific object