zephyr/samples/net/mqtt_sn_publisher
Chris Friedt bc4374b5fe posix: deprecate POSIX_MAX_FDS and add POSIX_DEVICE_IO
The POSIX_MAX_FDS option does not correspond to any standard
POSIX option. It was used to define the size of the file
descriptor table, which is by no means exclusively used by
POSIX (also net, fs, ...).

POSIX_MAX_FDS is being deprecated in order to ensure that
Zephyr's POSIX Kconfig variables correspond to those defined in
the specification, as of IEEE 1003.1-2017. Namely,
POSIX_OPEN_MAX. CONFIG_POSIX_MAX_OPEN_FILES is being deprecated
for the same reason.

To mitigate any possible layering violations, that option is
not user selectable. It tracks the newly added
CONFIG_ZVFS_OPEN_MAX option, which is native to Zephyr.

With this deprecation, we introduce the following Kconfig
options that map directly to standard POSIX Option Groups by
simply removing "CONFIG_":

* CONFIG_POSIX_DEVICE_IO

Similarly, with this deprecation, we introduce the following
Kconfig options that map directly to standard POSIX Options by
simply removing "CONFIG":

* CONFIG_POSIX_OPEN_MAX

In order to maintain parity with the current feature set, we
introduce the following Kconfig options.

* CONFIG_POSIX_DEVICE_IO_ALIAS_CLOSE
* CONFIG_POSIX_DEVICE_IO_ALIAS_OPEN
* CONFIG_POSIX_DEVICE_IO_ALIAS_READ
* CONFIG_POSIX_DEVICE_IO_ALIAS_WRITE

Gate open(), close(), read(), and write() via the
CONFIG_POSIX_DEVICE_IO Kconfig option and move
implementations into device_io.c, to be conformant with the
spec.

Lastly, stage function names for upcoming ZVFS work, to be
completed as part of the LTSv3 Roadmap (e.g. zvfs_open(), ..).

Signed-off-by: Chris Friedt <cfriedt@tenstorrent.com>
2024-06-04 16:27:12 -05:00
..
boards samples/net/gptp: Use hwmv2 native targets identifiers 2024-03-15 16:13:12 +01:00
src samples: net: Change to use CONFIG_POSIX_API 2024-03-27 13:40:13 -05:00
CMakeLists.txt samples: net: mqtt-sn: Add MQTT-SN publisher sample 2022-11-09 10:43:00 +01:00
Kconfig samples: net: mqtt-sn: Add MQTT-SN publisher sample 2022-11-09 10:43:00 +01:00
overlay-e1000.conf samples: net: mqtt-sn: Add MQTT-SN publisher sample 2022-11-09 10:43:00 +01:00
prj.conf posix: deprecate POSIX_MAX_FDS and add POSIX_DEVICE_IO 2024-06-04 16:27:12 -05:00
README.rst samples/net/gptp: Use hwmv2 native targets identifiers 2024-03-15 16:13:12 +01:00
sample.yaml samples/net/gptp: Use hwmv2 native targets identifiers 2024-03-15 16:13:12 +01:00

.. zephyr:code-sample:: mqtt-sn-publisher
   :name: MQTT-SN publisher
   :relevant-api: mqtt_sn_socket

   Send MQTT-SN PUBLISH messages to an MQTT-SN gateway.

Overview
********

`MQTT <http://mqtt.org/>`_ (MQ Telemetry Transport) is a lightweight
publish/subscribe messaging protocol optimized for small sensors and
mobile devices.

MQTT-SN can be considered as a version of MQTT which is adapted to
the peculiarities of a wireless communication environment. While MQTT
requires a reliable TCP/IP transport, MQTT-SN is designed to be usable
on any datagram-based transport like UDP, ZigBee or even a plain UART
(with an additional framing protocol).

The Zephyr MQTT-SN Publisher sample application is an MQTT-SN v1.2
client that sends MQTT-SN PUBLISH messages to an MQTT-SN gateway.
It also SUBSCRIBEs to a topic.
See the `MQTT-SN v1.2 spec`_ for more information.

.. _MQTT-SN v1.2 spec: https://www.oasis-open.org/committees/download.php/66091/MQTT-SN_spec_v1.2.pdf

The source code of this sample application can be found at:
:zephyr_file:`samples/net/mqtt_sn_publisher`.

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

- Linux machine
- MQTT-SN gateway, like Eclipse Paho
- Mosquitto server: any version that supports MQTT v3.1.1. This sample
  was tested with mosquitto 1.6.
- Mosquitto subscriber
- LAN for testing purposes (Ethernet)

Build and Running
*****************

Currently, this sample application only supports static IP addresses.
Open the :file:`prj.conf` file and set the IP addresses according
to the LAN environment.

You will also need to start an MQTT-SN gateway. With Paho, you can either
build it from source - see `PAHO MQTT-SN Gateway`_ - or run an unofficial
docker image, like `kyberpunk/paho`_.

.. _PAHO MQTT-SN Gateway: https://www.eclipse.org/paho/index.php?page=components/mqtt-sn-transparent-gateway/index.php
.. _kyberpunk/paho: https://hub.docker.com/r/kyberpunk/paho

On your Linux host computer, open 3 terminal windows. At first, start mosquitto:

.. code-block:: console

	$ sudo mosquitto -v -p 1883

Then, in another window, start the gateway, e.g. by using docker:

.. code-block:: console

	$ docker run -it -p 10000:10000 -p 10000:10000/udp --name paho -v $PWD/gateway.conf:/etc/paho/gateway.conf:ro kyberpunk/paho

Then, locate your zephyr directory and type:

.. zephyr-app-commands::
   :zephyr-app: samples/net/mqtt_sn_publisher
   :board: native_sim/native/64
   :goals: run
   :compact:

Optionally, use any MQTT explorer to connect to your broker.

Sample output
=============

This is the applications output:

.. code-block:: console

	WARNING: Using a test - not safe - entropy source
	*** Booting Zephyr OS build zephyr-v3.2.0-279-gc7fa387cea81  ***
	[00:00:00.000,000] <inf> net_config: Initializing network
	[00:00:00.000,000] <inf> net_config: IPv4 address: 172.18.0.20
	[00:00:00.000,000] <inf> mqtt_sn_publisher_sample: MQTT-SN sample
	[00:00:00.000,000] <inf> mqtt_sn_publisher_sample: Network connected
	[00:00:00.000,000] <inf> mqtt_sn_publisher_sample: Waiting for connection...
	[00:00:00.000,000] <inf> mqtt_sn_publisher_sample: Connecting client
	[00:00:00.510,000] <inf> net_mqtt_sn: Decoding message type: 5
	[00:00:00.510,000] <inf> net_mqtt_sn: Got message of type 5
	[00:00:00.510,000] <inf> net_mqtt_sn: MQTT_SN client connected
	[00:00:00.510,000] <inf> mqtt_sn_publisher_sample: MQTT-SN event EVT_CONNECTED
	[00:00:01.020,000] <inf> net_mqtt_sn: Decoding message type: 19
	[00:00:01.020,000] <inf> net_mqtt_sn: Got message of type 19
	[00:00:10.200,000] <inf> mqtt_sn_publisher_sample: Publishing timestamp
	[00:00:10.200,000] <inf> net_mqtt_sn: Registering topic
										2f 75 70 74 69 6d 65                             |/uptime
	[00:00:10.200,000] <inf> net_mqtt_sn: Can't publish; topic is not ready
	[00:00:10.710,000] <inf> net_mqtt_sn: Decoding message type: 11
	[00:00:10.710,000] <inf> net_mqtt_sn: Got message of type 11
	[00:00:10.710,000] <inf> net_mqtt_sn: Publishing to topic ID 14
	[00:00:20.400,000] <inf> mqtt_sn_publisher_sample: Publishing timestamp
	[00:00:20.400,000] <inf> net_mqtt_sn: Publishing to topic ID 14

This is the output from the MQTT-SN gateway:

.. code-block:: console

	20221024 140210.191   CONNECT           <---  ZEPHYR                              0C 04 04 01 00 3C 5A 45 50 48 59 52
	20221024 140210.192   CONNECT           ===>  ZEPHYR                              10 12 00 04 4D 51 54 54 04 02 00 3C 00 06 5A 45 50 48 59 52
	20221024 140210.192   CONNACK           <===  ZEPHYR                              20 02 00 00
	20221024 140210.192   CONNACK           --->  ZEPHYR                              03 05 00

	20221024 140210.643   SUBSCRIBE   0001  <---  ZEPHYR                              0C 12 00 00 01 2F 6E 75 6D 62 65 72
	20221024 140210.648   SUBSCRIBE   0001  ===>  ZEPHYR                              82 0C 00 01 00 07 2F 6E 75 6D 62 65 72 00
	20221024 140210.660   SUBACK      0001  <===  ZEPHYR                              90 03 00 01 00
	20221024 140210.661   SUBACK      0001  --->  ZEPHYR                              08 13 00 00 0D 00 01 00

	20221024 140220.338   REGISTER    0002  <---  ZEPHYR                              0D 0A 00 00 00 02 2F 75 70 74 69 6D 65
	20221024 140220.348   REGACK      0002  --->  ZEPHYR                              07 0B 00 0E 00 02 00

	20221024 140220.848   PUBLISH           <---  ZEPHYR                              0C 0C 00 00 0E 00 00 31 30 32 30 30
	20221024 140220.850   PUBLISH           ===>  ZEPHYR                              30 0E 00 07 2F 75 70 74 69 6D 65 31 30 32 30 30

	20221024 140230.539   PUBLISH           <---  ZEPHYR                              0C 0C 00 00 0E 00 00 32 30 34 30 30
	20221024 140230.542   PUBLISH           ===>  ZEPHYR                              30 0E 00 07 2F 75 70 74 69 6D 65 32 30 34 30 30