zephyr/samples/net/sockets/websocket_client
Keith Packard 0b90fd5adf samples, tests, boards: Switch main return type from void to int
As both C and C++ standards require applications running under an OS to
return 'int', adapt that for Zephyr to align with those standard. This also
eliminates errors when building with clang when not using -ffreestanding,
and reduces the need for compiler flags to silence warnings for both clang
and gcc.

Most of these changes were automated using coccinelle with the following
script:

@@
@@
- void
+ int
main(...) {
	...
-	return;
+	return 0;
	...
}

Approximately 40 files had to be edited by hand as coccinelle was unable to
fix them.

Signed-off-by: Keith Packard <keithp@keithp.com>
2023-04-14 07:49:41 +09:00
..
src samples, tests, boards: Switch main return type from void to int 2023-04-14 07:49:41 +09:00
CMakeLists.txt
overlay-tls.conf
prj.conf
README.rst
sample.yaml tests: remove intel adsp cavs platforms from filters 2023-04-06 18:51:56 +02:00

.. _sockets-websocket-client-sample:

Socket Websocket Client
#######################

Overview
********

This sample application implements a Websocket client that will do an HTTP
or HTTPS handshake request to HTTP server, then start to send data and wait for
the responses from the Websocket server.

The source code for this sample application can be found at:
:zephyr_file:`samples/net/sockets/websocket_client`.

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

- :ref:`networking_with_host`

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

You can use this application on a supported board, including
running it inside QEMU as described in :ref:`networking_with_qemu`.

Build websocket-client sample application like this:

.. zephyr-app-commands::
   :zephyr-app: samples/net/sockets/websocket_client
   :board: <board to use>
   :conf: <config file to use>
   :goals: build
   :compact:

Enabling TLS support
====================

Enable TLS support in the sample by building the project with the
``overlay-tls.conf`` overlay file enabled using these commands:

.. zephyr-app-commands::
   :zephyr-app: samples/net/sockets/websocket_client
   :board: qemu_x86
   :conf: "prj.conf overlay-tls.conf"
   :goals: build
   :compact:

An alternative way is to specify ``-DOVERLAY_CONFIG=overlay-tls.conf`` when
running ``west build`` or ``cmake``.

The certificate and private key used by the sample can be found in the sample's
:zephyr_file:`samples/net/sockets/websocket_client/src/` directory.


Running websocket-server in Linux Host
======================================

You can run this ``websocket-client`` sample application in QEMU
and run the ``zephyr-websocket-server.py`` (from net-tools) on a Linux host.
Other alternative is to install `websocketd <http://websocketd.com/>`_ and
use that.

To use QEMU for testing, follow the :ref:`networking_with_qemu` guide.

In a terminal window you can do either:

.. code-block:: console

    $ ./zephyr-websocket-server.py

or

.. code-block:: console

    $ websocketd --port=9001 cat

Run ``websocket-client`` application in QEMU:

.. zephyr-app-commands::
   :zephyr-app: samples/net/sockets/websocket_client
   :host-os: unix
   :board: qemu_x86
   :conf: prj.conf
   :goals: run
   :compact:

Note that ``zephyr-websocket-server.py`` or ``websocketd`` must be running in
the Linux host terminal window before you start the ``websocket-client``
application in QEMU. Exit QEMU by pressing :kbd:`CTRL+A` :kbd:`x`.

Current version of ``zephyr-websocket-server.py`` found in
`net-tools <https://github.com/zephyrproject-rtos/net-tools>`_ project, does
not support TLS.