### The communication between the IoT Box and a DB can be done using:

- Longpolling,
- Websocket,
- Simple fetch from one side or the other.

### Problems:

- The longpolling and the websocket can theorically be substituted but don't have a common API,
- The websocket service is currently designed to handle ONLY printing jobs,
- The longpolling is barely used, often replaced by a simple "action", but never polling 
(~never listening for response from the IoT Box),

### Solution:

We refactored all this in order to simplify the communication.

- `iot_longpolling` and `iot_websocket` services are replaced by a single `iot_http` service 
exposing available methods,
- Websocket can now call every IoT Box _action method_,
- Longpolling and Websocket now have a common simple API (`sendMessage`/`onMessage`),
- Longpolling can now fallback to websocket on every call (via `action` method),

#### List of the methods:

- `get`/`post`: base http methods to properly contact an IoT Box from the db client,
- `websocket.sendMessage`/`websocket.onMessage`: websocket methods,
- `longpolling.sendMessage`/`lonpolling.onMessage`: longpolling methods 
(+ `lonpolling.addListener`/`lonpolling.removeListener` kept for compatibility),
- `action`: general method to properly handle a simple communication between the db and 
the IoT Box, 

Community PR: [https://github.com/odoo/odoo/pull/185506](https://github.com/odoo/odoo/pull/185506)
Task: 4283647