sanic/docs/class_based_views.md

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# Class-Based Views
Class-based views are simply classes which implement response behaviour to
requests. They provide a way to compartmentalise handling of different HTTP
request types at the same endpoint. Rather than defining and decorating three
different handler functions, one for each of an endpoint's supported request
type, the endpoint can be assigned a class-based view.
## Defining views
A class-based view should subclass `HTTPMethodView`. You can then implement
class methods for every HTTP request type you want to support. If a request is
received that has no defined method, a `405: Method not allowed` response will
be generated.
To register a class-based view on an endpoint, the `app.add_route` method is
used. The first argument should be the defined class with the method `as_view`
invoked, and the second should be the URL endpoint.
The available methods are `get`, `post`, `put`, `patch`, and `delete`. A class
using all these methods would look like the following.
```python
from sanic import Sanic
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from sanic.views import HTTPMethodView
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from sanic.response import text
app = Sanic('some_name')
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class SimpleView(HTTPMethodView):
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def get(self, request):
return text('I am get method')
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def post(self, request):
return text('I am post method')
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def put(self, request):
return text('I am put method')
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def patch(self, request):
return text('I am patch method')
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def delete(self, request):
return text('I am delete method')
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app.add_route(SimpleView.as_view(), '/')
```
## URL parameters
If you need any URL parameters, as discussed in the routing guide, include them
in the method definition.
```python
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class NameView(HTTPMethodView):
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def get(self, request, name):
return text('Hello {}'.format(name))
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app.add_route(NameView.as_view(), '/<name>')
```
## Decorators
If you want to add any decorators to the class, you can set the `decorators`
class variable. These will be applied to the class when `as_view` is called.
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```
class ViewWithDecorator(HTTPMethodView):
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decorators = [some_decorator_here]
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def get(self, request, name):
return text('Hello I have a decorator')
app.add_route(ViewWithDecorator.as_view(), '/url')
```
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