Merge pull request #63 from eadwinCode/async_auth_class_doc

Asynchronous Auth Classes Documentation

Author: eadwinCode

docs/tutorial/authentication.md

@@ -48,5 +48,37 @@ api = NinjaExtraAPI(auth=GlobalAuth())
 ```
 Read more on django-ninja [authentication](https://django-ninja.rest-framework.com/tutorial/authentication/)
 
+## Asynchronous Auth Classes
+
+Ninja Extra added Asynchronous support for all `Auth` base classes provided by Django Ninja in `ninja_extra.security` package.
+And it maintained similar interface. It is important to noted that when using these asynchronous auth classes, the endpoint handler 
+**must** asynchronous functions.
+
+For example, lets re-write the first auth example with `AsyncHttpBearer` class.
+
+```Python
+from ninja_extra import api_controller, route
+from ninja_extra.security import AsyncHttpBearer
+from ninja.constants import NOT_SET
+
+
+class AuthBearer(AsyncHttpBearer):
+    async def authenticate(self, request, token):
+        # await some actions
+        if token == "supersecret":
+            return token
+
+
+@api_controller(tags=['My Operations'], auth=NOT_SET, permissions=[])
+class MyController:
+    @route.get("/bearer", auth=AuthBearer())
+    async def bearer(self):
+        return {"token": self.request.auth}
+
+```
+In example above, we changed `HttpBearer` to `AsyncHttpBearer` and changed bearer to `async` endpoint. 
+If `AuthBearer` is to be applied to a `MyController` **auth**, then all route handlers under `MyController` must be asynchronous route handlers.
+
+
 ## **JWT Authentication**
 if you want to use JWT authentication. See [ninja-jwt](https://pypi.org/project/django-ninja-jwt/)