Eclipse Zenoh

The Eclipse Zenoh: Zero Overhead Pub/sub, Store/Query and Compute.

Zenoh (pronounce /zeno/) unifies data in motion, data at rest and computations. It carefully blends traditional pub/sub with geo-distributed storages, queries and computations, while retaining a level of time and space efficiency that is well beyond any of the mainstream stacks.

Check the website zenoh.io and the roadmap for more detailed information.

---

Zenoh-Pico: native C library for constrained devices

zenoh-pico is the Eclipse zenoh implementation that targets constrained devices and offers a native C API. It is fully compatible with its main Rust Zenoh implementation, providing a lightweight implementation of most functionalities.

Currently, zenoh-pico provides support for the following (RT)OSs and protocols:

(RT)OS	Transport Layer	Network Layer	Data Link Layer
Unix	UDP (unicast and multicast), TCP	IPv4, IPv6, 6LoWPAN	WiFi, Ethernet, Thread
Windows	UDP (unicast and multicast), TCP	IPv4, IPv6	WiFi, Ethernet
Zephyr	UDP (unicast and multicast), TCP	IPv4, IPv6, 6LoWPAN	WiFi, Ethernet, Thread, Serial
Arduino	UDP (unicast and multicast), TCP	IPv4, IPv6	WiFi, Ethernet, Bluetooth (Serial profile), Serial
ESP-IDF	UDP (unicast and multicast), TCP	IPv4, IPv6	WiFi, Ethernet, Serial
MbedOS	UDP (unicast and multicast), TCP	IPv4, IPv6	WiFi, Ethernet, Serial
OpenCR	UDP (unicast and multicast), TCP	IPv4	WiFi
Emscripten	Websocket	IPv4, IPv6	WiFi, Ethernet

Check the website zenoh.io and the roadmap for more detailed information.

---

1. How to install it

The Eclipse zenoh-pico library is available as Debian, RPM, and tgz packages in the Eclipse zenoh-pico download area. Those packages are built using manylinux2010 x86-32 and x86-64 to be compatible with most of the Linux platforms. There are 2 kind of packages:

• libzenohpico: only contains the library file (.so)
• libzenohpico-dev: contains the zenoh-pico header files for development. Depends on libzenohpico package

For other platforms - like RTOS for embedded systems / microcontrollers -, you will need to clone and build the sources. Check below for more details.

---

2. How to build it

⚠️ WARNING ⚠️ : Zenoh and its ecosystem are under active development. When you build from git, make sure you also build from git any other Zenoh repository you plan to use (e.g. binding, plugin, backend, etc.). It may happen that some changes in git are not compatible with the most recent packaged Zenoh release (e.g. deb, docker, pip). We put particular effort in mantaining compatibility between the various git repositories in the Zenoh project.

2.1 Unix Environments

To build the zenoh-pico library, you need to ensure that cmake is available on your platform -- if not please install it.

Once the cmake dependency is satisfied, just do the following for CMake version 3 and higher:

-- CMake version 3 and higher --

$ cd /path/to/zenoh-pico
$ make
$ make install # on Linux use **sudo**

If you want to build with debug symbols, set the BUILD_TYPE=Debugenvironment variable before to run make:

$ cd /path/to/zenoh-pico
$ BUILD_TYPE=Debug make
$ make install # on Linux use **sudo**

For those that still have CMake version 2.8, do the following commands:

$ cd /path/to/zenoh-pico
$ mkdir build
$ cd build
$ cmake -DCMAKE_BUILD_TYPE=Release ../cmake-2.8
$ make
$ make install # on Linux use **sudo**

2.2. Real Time Operating System (RTOS) for Embedded Systems and Microcontrollers

In order to manage and ease the process of building and deploying into a a variety of platforms and frameworks for embedded systems and microcontrollers, PlatformIO can be used as a supporting platform.

Once the PlatformIO dependency is satisfied, follow the steps below for the tested micro controllers.

2.2.1. Zephyr

Note: tested with reel_board, nucleo-f767zi, nucleo-f420zi, and nRF52840 boards.

A typical PlatformIO project for Zephyr framework must have the following structure:

project_dir
├── include
├── lib
├── src
│    └── main.c
├── zephyr
│    ├── prj.conf
│    └── CMakeLists.txt
└── platformio.ini

To initialize this project structure, execute the following commands:

$ mkdir -p /path/to/project_dir
$ cd /path/to/project_dir
$ platformio init -b reel_board
$ platformio run

Include the CMakelist.txt and prj.conf in the project_dir/zephyr folder as shown in the structure above,

$ cp /path/to/zenoh-pico/docs/zephyr/reel_board/CMakelists.txt /path/to/project_dir/zephyr/
$ cp /path/to/zenoh-pico/docs/zephyr/reel_board/prj.conf /path/to/project_dir/zephyr/

and add zenoh-pico as a library by doing:

$ ln -s /path/to/zenoh-pico /path/to/project_dir/lib/zenoh-pico

or just include the following line in platformio.ini:

lib_deps = https://github.com/eclipse-zenoh/zenoh-pico

Finally, your code should go into project_dir/src/main.c. Check the examples provided in examples directory.

To build and upload the code into the board, run the following command:

platformio run
platformio run -t upload

2.2.2. Arduino

Note: tested with az-delivery-devkit-v4 ESP32 board

A typical PlatformIO project for Arduino framework must have the following structure:

project_dir
├── include
├── lib
├── src
│    └── main.ino
└── platformio.ini

To initialize this project structure, execute the following commands:

$ mkdir -p /path/to/project_dir
$ cd /path/to/project_dir
$ platformio init -b az-delivery-devkit-v4
$ platformio run

Add zenoh-pico as a library by doing:

$ ln -s /path/to/zenoh-pico /path/to/project_dir/lib/zenoh-pico

or just include the following line in platformio.ini:

lib_deps = https://github.com/eclipse-zenoh/zenoh-pico

Finally, your code should go into project_dir/src/main.ino. Check the examples provided in examples directory.

To build and upload the code into the board, run the following command:

platformio run
platformio run -t upload

2.2.3. ESP-IDF

Note: tested with az-delivery-devkit-v4 ESP32 board

A typical PlatformIO project for ESP-IDF framework must have the following structure:

project_dir
├── include
├── lib
├── src
|    ├── CMakeLists.txt
│    └── main.ino
├── CMakeLists.txt
└── platformio.ini

To initialize this project structure, execute the following commands:

$ mkdir -p /path/to/project_dir
$ cd /path/to/project_dir
$ platformio init -b az-delivery-devkit-v4
$ platformio run

Add zenoh-pico as a library by doing:

$ ln -s /path/to/zenoh-pico /path/to/project_dir/lib/zenoh-pico

or just include the following line in platformio.ini:

lib_deps = https://github.com/eclipse-zenoh/zenoh-pico

Finally, your code should go into project_dir/src/main.ino. Check the examples provided in examples directory.

To build and upload the code into the board, run the following command:

platformio run
platformio run -t upload

2.2.4. MbedOS

Note: tested with nucleo-f747zi and nucleo-f429zi boards

A typical PlatformIO project for MbedOS framework must have the following structure:

project_dir
├── include
├── src
│    └── main.ino
└── platformio.ini

To initialize this project structure, execute the following commands:

$ mkdir -p /path/to/project_dir
$ cd /path/to/project_dir
$ platformio init -b az-delivery-devkit-v4
$ platformio run

Add zenoh-pico as a library by doing:

$ ln -s /path/to/zenoh-pico /path/to/project_dir/lib/zenoh-pico

or just include the following line in platformio.ini:

lib_deps = https://github.com/eclipse-zenoh/zenoh-pico

Finally, your code should go into project_dir/src/main.ino. Check the examples provided in examples directory.

To build and upload the code into the board, run the following command:

platformio run
platformio run -t upload

2.2.5. OpenCR

Note: tested with ROBOTIS OpenCR 1.0 board

A typical PlatformIO project for OpenCR framework must have the following structure:

project_dir
├── include
├── lib
├── src
│    └── main.ino
└── platformio.ini

Note: to add support for OpenCR in PlatformIO, follow the steps presented in our blog.

To initialize this project structure, execute the following commands:

$ mkdir -p /path/to/project_dir
$ cd /path/to/project_dir
$ platformio init -b opencr
$ platformio run

Add zenoh-pico as a library by doing:

$ ln -s /path/to/zenoh-pico /path/to/project_dir/lib/zenoh-pico

or just include the following line in platformio.ini:

lib_deps = https://github.com/eclipse-zenoh/zenoh-pico

Finally, your code should go into project_dir/src/main.ino. Check the examples provided in examples directory.

To build and upload the code into the board, run the following command:

platformio run
platformio run -t upload

3. Running the Examples

The simplest way to run some of the example is to get a Docker image of the zenoh network router (see http://zenoh.io/docs/getting-started/quick-test/) and then to run the examples on your machine.

3.1. Starting the zenoh Network Service

Assuming you've pulled the Docker image of the zenoh network router on a Linux host (to leverage UDP multicast scouting has explained here, then simply do:

$ docker run --init --net host eclipse/zenoh:master

To see the zenoh manual page, simply do:

$ docker run --init --net host eclipse/zenoh:master --help

3.2. Basic Pub/Sub Example

Assuming that (1) you are running the zenoh network router, and (2) you are under the build directory, do:

$ ./z_sub

And on another shell, do:

$ ./z_pub

3.3. Basic Queryable/Get Example

Assuming you are running the zenoh network router, do:

$ ./z_queryable

And on another shell, do:

$ ./z_get