Note

This version of the book is based on zbus 2.0 API, which is currently in beta stages. For using the sample code in this book, you’ll need to explicitly depend on the latest beta.

The 1.0 version of this book is available here.

Introduction

zbus is a Rust crate for D-Bus. If you are not familiar with D-Bus, you should read what is D-Bus? first1. In short, zbus allows you to communicate from one program to another, using the D-Bus protocol. In other words, it’s an inter-process communication (IPC) solution. It is a very popular IPC solution on Linux and many Linux services (e.g systemd, NetworkManager) and desktop environments (e.g GNOME and KDE), rely on D-Bus for their IPC needs. There are many tools and implementations available, making it easy to interact with D-Bus programs from different languages and environments.

zbus is a 100% Rust-native implementation of the D-Bus protocol. It provides both an API to send and receive messages over a connection, as well as API to interact with peers through high-level concepts like method calls, signals and properties2. Thanks to the power of Rust macros, zbus is able to make interacting with D-Bus very easy.

zbus project provides two crates:

zvariant

D-Bus defines a marshalling format for its messages. The zvariant crate provides a serde-based API to serialize/deserialize Rust data types to/from this format. Outside of D-Bus context, a modified form of this format, GVariant is very commonly used for efficient storage of arbitrary data and is also supported by this crate.

zbus

The zbus crate provides the main API you will use to interact with D-Bus from Rust. It takes care of the establishment of a connection, the creation, sending and receiving of different kind of D-Bus messages (method calls, signals etc) for you.

zbus crate is currently Linux-specific3.

1

D-Bus is ~15y old, unfortunately many documents out there are sometime aging or misleading.

2

These concepts are explained in the following chapter.

3

Support for other OS exist, but it is not supported to the same extent. D-Bus clients in javascript (running from any browser) do exist though. And zbus may also be working from the browser sometime in the future too, thanks to Rust 🦀 and WebAssembly 🕸.