---
id: sanic-extensions
sidebar_label: Sanic Extensions
title: Sanic Extensions
---

:::info New in 3.6

You can now extend Sanic features such as middlewares, listeners, background tasks
and additional routes.

:::


You can now create additional Sanic extensions by accessing the app object created by the action server. The hook implemented
in the plugin package provides you access to the Sanic app object created by `rasa-sdk` when starting the action server.

## Step-by-step guide on creating your own Sanic extension in rasa_sdk
This example will show you how to create a Sanic listener using plugins.

### Create the rasa_sdk_plugins package
Create a package in your action server project which you must name `rasa_sdk_plugins`. Rasa SDK will try to instantiate this package in your project to start plugins.
If no plugins are found, it will print a debug log that there are no plugins in your project.

### Register modules containing the hooks
Create the package `rasa_sdk_plugins` and initialize the hooks by creating an `__init__.py` file where the plugin manager will look for the module where the hooks are implemented:

```
def init_hooks(manager: pluggy.PluginManager) -> None:
    """Initialise hooks into rasa sdk."""
    import sys
    import rasa_sdk_plugins.your_module

    logger.info("Finding hooks")
    manager.register(sys.modules["rasa_sdk_plugins.your_module"])
```
### Implement your hook
Implement the hook `attach_sanic_app_extensions`. This hook forwards the app object created by Sanic in the `rasa_sdk` and allows you to create additional routes, middlewares, listeners and background tasks. Here's an example of this implementation that creates a listener.

In your `rasa_sdk_plugins.your_module.py`:

```
from __future__ import annotations

import logging
import pluggy

from asyncio import AbstractEventLoop
from functools import partial


logger = logging.getLogger(__name__)
hookimpl = pluggy.HookimplMarker("rasa_sdk")


@hookimpl  # type: ignore[misc]
def attach_sanic_app_extensions(app: Sanic) -> None:
    logger.info("hook called")
    app.register_listener(
        partial(before_server_start),
        "before_server_start",
    )


async def before_server_start(app: Sanic, loop: AbstractEventLoop):
    logger.info("BEFORE SERVER START")
```
