.. zephyr:code-sample:: webusb-next
   :name: WebUSB-next
   :relevant-api: usbd_api

   Receive and echo data from a web page using WebUSB API.

Overview
********

This sample demonstrates how to use the Binary Device Object Store (BOS),
Microsoft OS 2.0 descriptors, and WebUSB descriptors to implement a WebUSB
sample application. The sample USB function receives the data and echoes back
to the WebUSB API based application running in the browser on your local host.
This sample can be found at :zephyr_file:`samples/subsys/usb/webusb-next` in the
Zephyr project tree.

Requirements
************

This project requires a USB device controller driver using the UDC API.
On your host computer, this project requires a web browser that supports the
WebUSB API, such as Chromium or a Chromium-based browser.

Building and Running
********************

Build and flash webusb sample with:

.. zephyr-app-commands::
   :zephyr-app: samples/subsys/usb/webusb-next
   :board: <board to use>
   :goals: flash
   :compact:

Demonstration
*************

The sample includes a simple WebUSB API application and can be found in the
sample directory: :zephyr_file:`samples/subsys/usb/webusb-next/index.html`.

There are two ways to access this sample page:

* Using browser go to :doc:`demo`

* Start a web server in the sample directory:

  .. code-block:: console

     $ python -m http.server

Then follow these steps:

#. Connect the board to your host.

#. Once the device has booted, you may see a notification from the browser: "Go
   to localhost to connect". Click on the notification to open the demo page.  If
   there is no notification from the browser, open the URL http://localhost:8001/
   in your browser.

#. Click on the :guilabel:`Connect` button to connect to the device.

#. Send some text to the device by clicking on the :guilabel:`Send` button.
   The demo application will receive the same text from the device and display
   it in the text area.

References
***********

WebUSB API Specification:
https://wicg.github.io/webusb/

Chrome for Developers, "Access USB Devices on the Web":
https://developer.chrome.com/docs/capabilities/usb