85 lines
2.1 KiB
Markdown
85 lines
2.1 KiB
Markdown
# Custom extensions
|
|
|
|
It is possible to create your own custom extensions.
|
|
|
|
Version 22.9 added the `Extend.register` [method](#extension-preregistration). This makes it extremely easy to add custom expensions to an application.
|
|
|
|
## Anatomy of an extension
|
|
|
|
All extensions must subclass `Extension`.
|
|
|
|
### Required
|
|
|
|
- `name`: By convention, the name is an all-lowercase string
|
|
- `startup`: A method that runs when the extension is added
|
|
|
|
### Optional
|
|
|
|
- `label`: A method that returns additional information about the extension in the MOTD
|
|
- `included`: A method that returns a boolean whether the extension should be enabled or not (could be used for example to check config state)
|
|
|
|
### Example
|
|
|
|
```python
|
|
from sanic import Request, Sanic, json
|
|
from sanic_ext import Extend, Extension
|
|
|
|
app = Sanic(__name__)
|
|
app.config.MONITOR = True
|
|
|
|
class AutoMonitor(Extension):
|
|
name = "automonitor"
|
|
|
|
def startup(self, bootstrap) -> None:
|
|
if self.included():
|
|
self.app.before_server_start(self.ensure_monitor_set)
|
|
self.app.on_request(self.monitor)
|
|
|
|
@staticmethod
|
|
async def monitor(request: Request):
|
|
if request.route and request.route.ctx.monitor:
|
|
print("....")
|
|
|
|
@staticmethod
|
|
async def ensure_monitor_set(app: Sanic):
|
|
for route in app.router.routes:
|
|
if not hasattr(route.ctx, "monitor"):
|
|
route.ctx.monitor = False
|
|
|
|
def label(self):
|
|
has_monitor = [
|
|
route
|
|
for route in self.app.router.routes
|
|
if getattr(route.ctx, "monitor", None)
|
|
]
|
|
return f"{len(has_monitor)} endpoint(s)"
|
|
|
|
def included(self):
|
|
return self.app.config.MONITOR
|
|
|
|
Extend.register(AutoMonitor)
|
|
|
|
@app.get("/", ctx_monitor=True)
|
|
async def handler(request: Request):
|
|
return json({"foo": "bar"})
|
|
```
|
|
|
|
## Extension preregistration
|
|
|
|
.. column::
|
|
|
|
`Extend.register` simplifies the addition of custom extensions.
|
|
|
|
.. column::
|
|
|
|
```python
|
|
from sanic_ext import Extend, Extension
|
|
|
|
class MyCustomExtension(Extension):
|
|
...
|
|
|
|
Extend.register(MyCustomExtension())
|
|
```
|
|
|
|
*Added in v22.9*
|