Traversal

правильный способ обработки URL

• Model
• View
• Controller

• Model Model
• View Template
• Controller View

Регулярные выражения

«традиционный» способ

Route → View

Route → View

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

/user/vpupkin/blog/42/like

• /user/{user_id}/
• /user/{user_id}/blog/
• /user/{user_id}/blog/{post_id}/
• /user/{user_id}/blog/{post_id}/like
• /user/{user_id}/blog/{post_id}/add-comment

{'user_id': 'vpupkin', 'post_id': '42'}

Traversal

Resource + View name → View

Resource + View name → View

Resource + View name → View

@view_config(context=Resource, name='someview')
def someview(context, request):

Resource

• __name__
• __parent__
• __getitem__()

Resource

• __name__
• __parent__
• __getitem__()

Resource

• __name__
• __parent__
• __getitem__()

Resource

• __name__
• __parent__
• __getitem__()

SiteRoot['user']
    Users['{user_id}']
        User['blog']
            Blog['{post_id}']
                BlogPost

/user/vpupkin/blog/42/like

['user', 'vpupkin', 'blog', '42', 'like']

context = root_factory()# <SiteRoot object>

['vpupkin', 'blog', '42', 'like']

context = context['user']# <Users object>

['blog', '42', 'like']

context = context['vpupkin']# <User object>

['42', 'like']

context = context['blog']# <Blog object>

['like']

context = context['42']# <BlogPost object>

[]

context = context['like']# <BlogPost object>

KeyError: 'like'

[]

context = BlogPost('42')

view_name = 'like'

Зачем так сложно?

• ModelДоступ к данным
•  
• View Действия пользователя
• Template Представление

• ModelДоступ к данным
•  Бизнес логика
• View Действия пользователя
• Template Представление

• ModelДоступ к данным
• ResourceБизнес логика
• View Действия пользователя
• Template Представление

• Model
• Resource
• View + Template

• Model
• Resource
• View + Template: Web, RPC, CLI

• Model: RDBMS, NoSQL, REST, RPC
• Resource
• View + Template: Web, RPC, CLI

Resource + views = изолированный компонент

Blog index, archive

BlogPost show, create, edit, delete

SiteRoot
    Users
        User
            Blog
    Groups
        Group
            Blog
    Blog

SiteRoot
    Users
        User
            Blog
    Groups
        Group
            Blog
    Blog

SiteRoot
    Users
        User
            Blog
    Groups
        Group
            Blog
    Blog

Mixins

Commentable add_comment, delete_comment

Likeable like, unlike

• BlogPost(Resource, Commentable, Likeable)
• Photo(Resource, Commentable, Likeable)
• User(Resource, Commentable)

Commentable add_comment, delete_comment

Likeable like, unlike

• BlogPost(Resource, Commentable, Likeable)
• Photo(Resource, Commentable, Likeable)
• User(Resource, Commentable)

Commentable add_comment, delete_comment

Likeable like, unlike

• BlogPost(Resource, Commentable, Likeable)
• Photo(Resource, Commentable, Likeable)
• User(Resource, Commentable)

Commentable add_comment, delete_comment

Likeable like, unlike

• BlogPost(Resource, Commentable, Likeable)
• Photo(Resource, Commentable, Likeable)
• User(Resource, Commentable)

Бонусы

Простой и логичный реверс-роутинг

resource_url(resource, view_name)

ACL

Blog

•  (Allow, Everyone, 'view')
•  (Allow, Authenticated, 'add')
•  (Allow, 'group:moderators', 'edit')

Blog

•  (Allow, Everyone, 'view')
•  (Allow, Authenticated, 'add')
•  (Allow, 'group:moderators', 'edit')

BlogPost

•  (Allow, owner_id, 'edit')

Тесты

Спасибо за внимание