Xenon

What is it?

Xenon is a middleware abstraction library. It provides a simple programming interface to various pieces of software that can be used to access distributed compute and storage resources.

Why Xenon?

Xenon is developed by the Netherlands eScience Center as a support library for our projects. Several projects develop end-user applications that require access to distributed compute and storage resources. Xenon provides a simple API to those resources, allowing those applications to be developed more rapidly. The experience gained during end-user application development is used to improve the Xenon API and implementation.

The Latest Version

Available in JCenter

Details of the latest official release of Xenon can be found at:

https://github.com/NLeSC/Xenon/releases

Alternatively, the latest development versions of Xenon can be found at:

https://github.com/NLeSC/Xenon.

Quick start

Add Xenon library as a dependency to your project. For a Maven project use

<dependency>
  <groupId>nl.esciencecenter.xenon</groupId>
  <artifactId>xenon</artifactId>
  <version>1.1.0</version>
</dependency>

For a gradle project make sure to include jcenter in the list of repositories, for example:

repositories {
    mavenCentral()
    jcenter()
}

Then include Xenon as a compile dependency:

dependencies {
    compile group: 'nl.esciencecenter.xenon', name: 'xenon', version: '1.1.0'
    // other dependencies ...
}

To compile Xenon from source, download the source distribution below and type:

gradlew installDist

This will create a binary distribution in ./build/install

Simple examples

Here are some examples of basic operations you can perform with Xenon:

Copy a file

Following code copies local /etc/passwd file using ssh to /tmp/password on somemachine:

xenon = XenonFactory.newXenon(null);
Files files = xenon.files();
FileSystem sourceFS = files.newFileSystem("local", null, null, null);
FileSystem targetFS = files.newFileSystem("ssh", "somemachine", null, null);
Path sourcePath = files.newPath(sourceFS, new RelativePath("/etc/passwd"));
Path targetPath = files.newPath(targetFS, new RelativePath("/tmp/passwd"));

files.copy(sourcePath, targetPath, CopyOption.CREATE);

files.close(sourceFS);
files.close(targetFS);
XenonFactory.endXenon(xenon);

Run a job

Following code performs a wordcount of a file on somemachine using ssh:

xenon = XenonFactory.newXenon(null);
Jobs jobs = xenon.jobs();
Scheduler scheduler = jobs.newScheduler("ssh", "somemachine", null, null);
JobDescription description = new JobDescription();
description.setExecutable("/bin/wc");
description.setArguments("-l", "/tmp/passwd");
description.setStdout("/tmp/stdout.txt");

Job job = jobs.submitJob(scheduler, description);

jobs.close(scheduler);
XenonFactory.endXenon(xenon);

The output of the job will be written to /tmp/stdout.txt file on somemachine.

Supported middleware

Xenon currently supports the following file access mechanisms:

local
ssh
ftp
sftp
WebDAV

Xenon currently supports the following job submission mechanisms:

local (interactive jobs only)
ssh (interactive jobs only)
Slurm (interactive and batch jobs)
Torque (batch jobs only)
GridEngine (batch jobs only)

Planned extensions include:

S3
Swift
HDFS
YARN
GridFTP
glite
Azure-Batch

Documentation

See https://github.com/NLeSC/Xenon-examples for examples how to use the Xenon library.

See https://github.com/NLeSC/Xenon-examples/raw/master/doc/tutorial/xenon-tutorial.pdf for a tutorial pdf targeting inexperienced users.

The javadoc of Xenon library is available online at http://nlesc.github.io/Xenon/versions/1.1.0/javadoc.

See the file https://github.com/NLeSC/Xenon/blob/master/doc/README.md for information for developers of the Xenon library.

Copyrights & Disclaimers

Xenon is copyrighted by the Netherlands eScience Center and releases under the Apache License, Version 2.0.

See http://www.esciencecenter.nl for more information on the Netherlands eScience Center.

See the "LICENSE" and "NOTICE" files for more information.

Third party libraries

This product includes the JaCoCo library, which is Copyright (c) 2009, 2013 Mountainminds GmbH & Co. KG and Contributors. See "notices/LICENSE.jacoco.txt" for the licence information of the JaCoCo library.

This project includes the JUnit library. See "notices/LICENSE.junit.txt" for the licence information of the JUnit library.

This project includes the Commons-logging library, which is Copyright (c) Apache Software Foundation. See "notices/LICENSE.commons-logging.txt" for the licence information of the Commons-logging library.

This project includes the log4j library, which is Copyright (c) Apache Software Foundation. See "notices/LICENSE.log4j.txt" for the licence information of the log4j library.

This project includes the Legion of the Bouncy Castle Java cryptography APIs, which are Copyright (c) 2000-2013 The Legion Of The Bouncy Castle. See "notices/LICENSE.bouncycastle.txt" for the licence information of this library.

This project includes the pureTLS library, which is Copyright (c) Claymore Systems, Inc. See "notices/LICENSE.puretls.txt" for the licence information of the pureTLS library.

This project includes libraries produced by the Cryptix Project. See "notices/LICENSE.cryptix.txt" for the licence information of these libraries.

sonjageorgievska/Xenon