{"id":18461788,"url":"https://github.com/dancergraham/headfirstdesignpatterns_python","last_synced_at":"2025-04-05T17:04:30.203Z","repository":{"id":37990217,"uuid":"376605201","full_name":"dancergraham/HeadFirstDesignPatterns_python","owner":"dancergraham","description":"Example code from Head First Design Patterns translated to python","archived":false,"fork":false,"pushed_at":"2025-01-25T14:27:07.000Z","size":266,"stargazers_count":107,"open_issues_count":3,"forks_count":42,"subscribers_count":2,"default_branch":"main","last_synced_at":"2025-03-29T16:06:58.441Z","etag":null,"topics":["design-pattern","design-patterns","factory","headfirst","object-oriented-programming","observer-pattern","oop","python","strategy"],"latest_commit_sha":null,"homepage":"","language":"Python","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/dancergraham.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":"CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2021-06-13T17:43:20.000Z","updated_at":"2025-03-19T06:23:44.000Z","dependencies_parsed_at":"2023-02-09T04:01:18.550Z","dependency_job_id":"7fbc0f34-8f10-4ecf-a17b-fbc230e49857","html_url":"https://github.com/dancergraham/HeadFirstDesignPatterns_python","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/dancergraham%2FHeadFirstDesignPatterns_python","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/dancergraham%2FHeadFirstDesignPatterns_python/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/dancergraham%2FHeadFirstDesignPatterns_python/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/dancergraham%2FHeadFirstDesignPatterns_python/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/dancergraham","download_url":"https://codeload.github.com/dancergraham/HeadFirstDesignPatterns_python/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":247369953,"owners_count":20927928,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["design-pattern","design-patterns","factory","headfirst","object-oriented-programming","observer-pattern","oop","python","strategy"],"created_at":"2024-11-06T08:36:41.944Z","updated_at":"2025-04-05T17:04:30.183Z","avatar_url":"https://github.com/dancergraham.png","language":"Python","readme":"# Head First Design Patterns python code\n\n\u003cimg src=\"images\\learning.oreilly.jpg\" alt=\"Head First Design Patterns Second Edition\" width=\"200\" align=\"right\"\u003eExample code from [Head First Design Patterns second edition](https://wickedlysmart.com/head-first-design-patterns/) translated to python to help me understand and memorise the patterns.\n\nI have added examples of pattern usage in the Python standard library and pypi - I am starting to see patterns everywhere!\n\n\u003e **Note**\n\u003e I am aiming for a mostly literal translation whilst trying to make the code a little more pythonic by, e.g. using python conventions for `ClassNames` and `method_names` and putting all of the code in a single file where it makes sense to do so.\n\n## Patterns Implemented\n\n- [x] [Strategy](chapter01_strategy)\n- [x] [Observer](chapter02_observer)\n- [x] [Decorator](chapter03_decorator)\n- [ ] [Factory Method](chapter04_factory)\n- [ ] [Simple Factory](chapter04_factory)\n- [x] [Abstract Factory](chapter04_factory)\n- [ ] [Builder](chapter04_factory#builder-%EF%B8%8F%EF%B8%8F) _(Bonus Pattern)_\n- [x] [Singleton](chapter05_singleton)\n- [x] [Command](chapter06_command)\n- [x] [Adapter](chapter07_adapter_facade)\n- [x] [Façade](chapter07_adapter_facade)\n- [x] [Template Method](chapter08_template)\n- [x] [Iterator](chapter09_iterator_composite)\n- [ ] [Composite](chapter09_iterator_composite)\n- [x] [State](chapter10_state)\n- [ ] Proxy\n- [ ] [Model View Controller (MVC)](chapter12_compound)\n- [ ] [Manager](chapter14_leftover) _(Bonus Pattern)_\n- [ ] [Result](extra_result) _(Bonus Pattern)_\n\n\n## Sample Code : Java\n\nFrom the book 📖:\n \n```java\npackage headfirst.designpatterns.strategy;\n\npublic abstract class Duck {\n    FlyBehavior flyBehavior;\n    QuackBehavior quackBehavior;\n\n    public Duck() {\n    }\n\n    public void setFlyBehavior(FlyBehavior fb) {\n        flyBehavior = fb;\n    }\n\n    public void setQuackBehavior(QuackBehavior qb) {\n        quackBehavior = qb;\n    }\n\n    abstract void display();\n\n    public void performFly() {\n        flyBehavior.fly();\n    }\n\n    public void performQuack() {\n        quackBehavior.quack();\n    }\n\n    public void swim() {\n        System.out.println(\"All ducks float, even decoys!\");\n    }\n}\n```\n\n### Sample Code : Python 🐍\n\nFrom this repository :\n\n```python\nclass Duck():\n    _fly_behavior = None\n    _quack_behavior = None\n\n    def set_fly_behavior(self, fly_behavior):\n        self._fly_behavior = fly_behavior\n\n    def set_quack_behavior(self, quack_behavior):\n        self._quack_behavior = quack_behavior\n\n    def display(self):\n        raise NotImplementedError\n\n    def perform_fly(self):\n        self._fly_behavior.fly()\n\n    def perform_quack(self):\n        self._quack_behavior.quack()\n\n    def swim(self):\n        print(\"All ducks float, even decoys! 〰🦆〰\")\n```\n\n## Object Oriented Design Principles\n\n- Encapsulate what varies\n- Open-Closed Principle: Open for extension, closed for modification\n- Program to an interface, not to an implementation\n- Favour composition over inheritence\n- Dependency Inversion Principle\n- Depend upon abstractions\n- The Hollywood Principle : _\"Don't call us, we'll call you\"_\n- One Class, One Responsibility Principle\n- Single Responsibility Principle\n- Principle of Least Knowledge\n\n## Model View Controller (MVC)\n\nI started to work on the MVC pattern here but have a [small complete MVC implementation in JavaScript](https://github.com/dancergraham/HeadFirstJs/blob/master/battleship2D.js) in another repo. \n","funding_links":[],"categories":[],"sub_categories":[],"project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fdancergraham%2Fheadfirstdesignpatterns_python","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fdancergraham%2Fheadfirstdesignpatterns_python","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fdancergraham%2Fheadfirstdesignpatterns_python/lists"}