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.
This repository provides a Kotlin binding based on the main Zenoh implementation written in Rust.
The code relies on the Zenoh JNI native library, which written in Rust and communicates with the Kotlin layer via the Java Native Interface (JNI).
The documentation of the API is published at https://eclipse-zenoh.github.io/zenoh-kotlin/index.html.
Alternatively, you can build it locally as explained below.
The released packages can be found in the "packages" section of this repository, or in the links below:
These are 'nightly' packages that need to be imported as explained in the following sections of this README. We plan to publish our packages into Maven central in the very short term.
For this first version we have published a Github package with the library which can be imported on your projects.
Checkout the Zenoh demo app for an example on how to use the library.
First add the Github packages repository to your settings.gradle.kts
:
dependencyResolutionManagement {
// ...
repositories {
google()
mavenCentral()
maven {
name = "GitHubPackages"
url = uri("https://maven.pkg.github.com/eclipse-zenoh/zenoh-kotlin")
credentials {
username = providers.gradleProperty("user").get()
password = providers.gradleProperty("token").get()
}
}
}
}
where the username and token are your github username and a personal access token you need to generate on github with package read permissions (see the Github documentation). This is required by Github in order to import the package, even if it's from a public repository.
After that add to the dependencies in the app's build.gradle.kts
:
implementation("org.eclipse.zenoh:zenoh-kotlin-android:1.0.0")
The library targets the following platforms:
- x86
- x86_64
- arm
- arm64
The minimum SDK is 30.
Zenoh is a communications protocol, therefore the permissions required are:
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
Similar to Android, we have published a Github package to import on your projects.
First add the Github packages repository to your settings.gradle.kts
:
dependencyResolutionManagement {
// ...
repositories {
google()
mavenCentral()
maven {
name = "GitHubPackages"
url = uri("https://maven.pkg.github.com/eclipse-zenoh/zenoh-kotlin")
credentials {
username = providers.gradleProperty("user").get()
password = providers.gradleProperty("token").get()
}
}
}
}
where the username and token are your github username and a personal access token you need to generate on github with package read permissions (see the Github documentation). This is required by Github in order to import the package, even if it's from a public repository.
After that add to the dependencies in the app's build.gradle.kts
:
implementation("io.zenoh:zenoh-kotlin-jvm:1.0.0")
For the moment, the library targets the following platforms:
- x86_64-unknown-linux-gnu
- aarch64-unknown-linux-gnu
- x86_64-apple-darwin
- aarch64-apple-darwin
- x86_64-pc-windows-msvc
Basically:
- Rust (Installation guide)
- Kotlin (Installation guide)
- Gradle (Installation guide)
and in case of targetting Android you'll also need:
- Android SDK (Installation guide)
To publish a library for a JVM project into Maven local, run
gradle -Prelease=true publishJvmPublicationToMavenLocal
This will first, trigger the compilation of Zenoh-JNI in release (if you want debug, specify -Prelease=false
), and second publish the library into maven local, containing the native library
as a resource that will be loaded during runtime.
Once we have published the package, we should be able to find it under ~/.m2/repository/io/zenoh/zenoh-kotlin-jvm/1.0.0
.
Finally, in the build.gradle.kts
file of the project where you intend to use this library, add mavenLocal to the list of repositories and add zenoh-kotlin as a dependency:
repositories {
mavenCentral()
mavenLocal()
}
dependencies {
testImplementation(kotlin("test"))
implementation("io.zenoh:zenoh-kotlin-jvm:1.0.0")
}
In order to use these bindings in a native Android project, what we will do is to build them as an Android NDK Library, publishing it into Maven local for us to be able to easily import it in our project.
It is required to have the NDK (native development kit) installed, since we are going to compile Zenoh JNI for multiple
android native targets. The currently used NDK version is 26.0.10792818.
It can be set up by using Android Studio (go to Preferences > Languages & Frameworks > Android SDK > SDK Tools
, tick Show Package Details
and pick the right NDK version),
or alternatively it can be found here.
The native platforms we are going to target are the following ones:
- x86
- x86_64
- arm
- arm64
Therefore, if they are not yet already added to the Rust toolchain, run:
rustup target add armv7-linux-androideabi; \
rustup target add i686-linux-android; \
rustup target add aarch64-linux-android; \
rustup target add x86_64-linux-android
to install them.
So, in order to publish the library onto Maven Local, run:
gradle -Pandroid=true publishAndroidReleasePublicationToMavenLocal
This will first trigger the compilation of the Zenoh-JNI for the previously mentioned targets, and secondly will publish the library, containing the native binaries.
You should now be able to see the package under ~/.m2/repository/io/zenoh/zenoh-kotlin-android/1.0.0
with the following files:
zenoh-kotlin-android-1.0.0-sources.jar
zenoh-kotlin-android-1.0.0.aar
zenoh-kotlin-android-1.0.0.module
zenoh-kotlin-android-1.0.0.pom
Now the library is published on maven local, let's now see how to import it into an Android project.
First, we need to indicate we want to look into mavenLocal for our library, so in your top level build.gradle.kts
you need to specify
the mavenLocal
repository:
repositories {
mavenCentral()
...
mavenLocal() // We add this line
}
Then in your app's build.gradle.kts
filen add the dependency:
implementation("io.zenoh:zenoh-kotlin-android:1.0.0")
And finally, do not forget to add the required internet permissions on your manifest!
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
And that was it! You can now import the code from the io.zenoh
package and use it at your will.
Because it's a Kotlin project, we use Dokka to generate the documentation.
In order to build it, run:
gradle zenoh-kotlin:dokkaHtml
To run the tests, run:
gradle jvmTest
This will compile the native library on debug mode (if not already available) and run the tests afterward against the JVM target.
Running the tests against the Android target (by using gradle testDebugUnitTest
) is equivalent to running them against the JVM one, since they are common
tests executed locally as Unit tests.
Rust logs are propagated when setting the RUST_LOG
environment variable.
For instance running the ZPub test as follows:
RUST_LOG=debug gradle ZPub
causes the logs to appear in standard output.
The log levels are the ones from Rust: trace
, info
, debug
, error
and warn
.
You can find some examples located under the /examples
folder.
Once we've built the project, to run them, simply run ./gradlew <EXAMPLE_NAME>
.
For instance in order to run the ZPub example, type:
./gradlew ZPub
You can find more info about these examples on the examples README file.