zephyr

History

Robert Lubos f85e37ae2c samples: net: sockets: coap_client: Make use of CoAP APIs for observe The sample oversimplified the observe mechanism a bit - instead of making use of CoAP APIs to verify the packets received (if they are actually notifications for the observe) it blindly assumed that any received packet was a notification. This could be misleading for potential users of the CoAP library, as the sample had little use as a reference for the Observer functionality. Fix this by making use of `coap_reply` structure and a corresponding `coap_response_received()` function. Additionally, make the observe cancellation compliant with the CoAP specification - it should be either an empty Reset message, or a GET request with Observe option set to 1. The sample used invalid construct of a Reset message with Observe option. For the purpose of the sample, use the latter option. Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>		2021-12-06 08:09:13 -05:00
..
src	samples: net: sockets: coap_client: Make use of CoAP APIs for observe	2021-12-06 08:09:13 -05:00
CMakeLists.txt	cmake: increase minimal required version to 3.20.0	2021-08-20 09:47:34 +02:00
prj.conf
README.rst
sample.yaml

README.rst

.. _coap-client-sample:

CoAP client
###########

Overview
********

This sample is a simple CoAP client showing how to retrieve information
from a resource.

This demo assumes that the platform of choice has networking support,
some adjustments to the configuration may be needed.

This sample will make a GET request with path 'test' to the IPv6
multicast address reserved for CoAP nodes, so the URI can be
represented as:

.. code-block:: none

    coap://[ff02::fd]:5683/test

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

This project will print all the octets of the response received, more context can
be obtained by using a tool such as tcpdump or wireshark.

See the `net-tools`_ project for more details.

This sample can be built and executed on QEMU or native_posix board as described
in :ref:`networking_with_host`.

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

.. code-block:: console

  reply: 60 00 00 00 00 24 11 40 fe 80 00 00 00 00 00 00 5c 25 e2 ff fe
  15 01 01 fe 80 00 00 00 00 00 00 5c 25 e2 ff fe 15 01 01 16 33 16 33
  00 24 3d 86 60 40 00 01 ff 54 79 70 65 3a 20 30 0a 43 6f 64 65 3a 20
  31 0a 4d 49 44 3a 20 31 0a (76 bytes)

.. note: The values shown above might differ.

.. _`net-tools`: https://github.com/zephyrproject-rtos/net-tools