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Nuts and Maven

You'd still be Maven, yet you gonna be Nuts​

Is there any package manager for Java(TM) applications? You can google for it and you will find that many have queried this on blogs and forums. In most cases responses point to maven and gradle, the tremendous build tools. However, both maven and gradle are build tools, while helping build packages they lack of deployment features. They bundle every dependency in every package (think of wars, ears and standalone jars). They do not handle installation or upgrading. Apache ivy, as well, while competing with maven build tool does not provide more than transitive dependency management.
The main idea behind a package manager is the automation of installation, update, configuration and removal of programs or libraries in a coherent manner with the help of a database that manages binaries and metadata. maven, to consider one, sticks to the build process, an goes no further.

You may also ask, "Why ever, do we need a package manager for Java(TM) applications". Okkay, let's take some example of Java(TM) applications. How can we install apache netbeans IDE ? The proper way is to browse to the editor's website, select the proper mirror if applicable, download the archive, uncompress it, chmod the main binary (i'm a linux guy) and adjust PATH environment variable to point to this binary; Quite a pain. What do we do to update it now? Hopefully, the IDE has a solid plugin architecture and an in-app update/upgrade tool that will help the process (in a gui manner of course). The same applies to eclipse and apache tomcat with the exception that apache tomcat does not even bundle an in-app update tool. The same applies too when dealing with other operating systems (Windows, MacOS, ...). Managing Java(TM) applications is far from helpful.

Furthermore, as Java(TM) applications are (usually) not bundled in OS-aware installers, you will end up with a spaguetty home directory with applications installed all over your partitions, which - simply - does not mix up with all the work OS-developers have done to separate logs from data, from temporary files, from binaries, etc. Each application will handle it's files in a very specific manner that would make it hard to manage own's disk (automatic archive/backup/restore) or roaming applications across machines, etc.

Moreover, in a world of containers and devops, deployments of Java(TM) applications need to be automatable and reproducible with the highest level of simplicity, configurability and integrability. Installing tomcat on a custom port should not not be as painful as using a custom Docker image or a complicated Dockerfile or even a custom apache tomcat bundle.

When we recall that Java(TM) is the one language that has the more versatile number of libraries, frameworks and tools, I find it annoying not to have a decent package manager to make the leap and provide facilities I find prime in other languages and platforms (pip/python, npm/nodejs/javascript) and most of linux distribution (zypper/opensuse, dnf/redhat apt-get/debian/ubuntu)

Hence I'm introducing here a humble attempt to provide a tiny (300ko) yet powerful package manager for Java(TM) applications (but not only) that should handle jar files seamlessly (with little or no modification) and that comes with a set of portable tools that makes this management at a higher level. I'm not talking about redefining the wheel. I'm aware that many tools such as maven, are already very good at what they do, I just needed to make the leap for deployments. You will be able to deploy your applications without bundling all of their dependencies : nuts will take care of that.

So you'd still be maven, yet you gonna be nuts.

Nuts Package manager​

nuts is actually :

  • a transitive dependency resolution manager
  • a package manager (backports maven and supports maven repositories)
  • an automation tool
  • a feature rich toolset
  • an application framework
  • decentralized
  • sandbox based

Transitive dependency resolution manager​

nuts calculates transitive dependencies of an application to resolve other packages to download at install or update/upgrade time. So typically, deployed applications should no more bundle their dependencies within the deployed archive. Thus we avoid the annoying fat jars (using maven plugins like 'maven-assembly-plugin' and 'maven-shade-plugin') and lib folders (using 'maven-dependency-plugin'). It will also reuse dependencies and packages across multiple installed applications and hence save disk space, and network bandwidth.

All what nuts needs is a descriptor file withing the jar file that defines the immediate dependencies. It then calculates all transitive dependencies automatically. And guess what, all maven built jars already contain that descriptor : the pom.xml file. So basically all maven applications are already nuts aware applications.

Package manager​

nuts uses this dependency resolution to help install, update, remove and search for applications. To be able to use an application, it has to be installed and configured with all of its dependencies. This is the main goal of nuts. When we ask to install tomcat, for instance, it will search for the best version in registered repositories, download it, and configure it to be ready for execution. The best version is not always the the latest one. Actually it would be the latest valid one, thus the latest one that matches some constraints.
Constraints include the version of the running java (tomcat 8 works on java 7 but not 6 for instance), the running operating system (windows, linux, ... to help selecting the proper binaries), may be the hardware architecture or even the operating distribution (for linux based systems). Constraints will filter the search result to include the best, the most accurate version to install. Installation also would configure the installed application and even may run another artifact to help this configuration.

nuts also handles search for newer versions and update the installed application at request. Updating a software does not necessarily delete the older version. Both version can coexist and it is up to the user the decide whether or not to retain both versions. Indeed, one of the key features of nuts is the ability to install and hence run multiple versions of the same software in parallel. You would never see an error message telling you can't install that software because a dependency of it is installed with different version. All software and all libraries can coexist peacefully.

Software artifacts are stored in repositories. nuts can handle multiple repositories, remote and local ones. Installed software are stored in special local repositories. Supported repositories include maven repositories and github repositories. Actually a fresh installation of nuts is configured with maven central repository so that, you already have access to thousands of installable artifacts.

At some point, you may need to uninstall an artifact and that's to undo the artifact installation.
Installation will help you choose between uninstalling binaries only and keeping data/config files or remove permanently all of the artifact files. In all ways, uninstalling will not affect other artifacts that use the same dependencies if ever.

Feature rich Toolset​

nuts is intended to be used either by human users or by robots and other applications. It comes with portable, feature rich toolset, a versatile library and a handy parsable result.

nuts is mainly a commandline program that helps installing, uninstalling, searching, updating and running artifacts. To help desktop integration, nuts installs by default a set of other companion tools such as nsh (a portable bash-compatible implementation), and nadmin (an administration tool for nuts to configure users, authorizations, repositories, create scripts,...);

nsh brings the bash facilities to all environments (windows included) in a very portable manner. Besides it integrates well with the installed nuts version. Several common commands are ported to nsh such as cat,head, and ssh, as well as core features like pipes, redirection and scripts.

nadmin is intended for configuring nuts workspaces, managing repositories and users. It helps also configuring sub commands and aliases to make nuts usage even easier.

Nuts Workspaces​

One of the key features of nuts is the ability to support multiple isolated workspaces, each managing it's own repositories, applications and libraries; each defining it's sandbox security constraints. Thus non-root installation is made easy while it remains possible to overlap between workspaces by sharing repositories. Roaming is also supported, so that a workspaces can be copied/moved across machines.

Application Framework​

nuts can also be embedded as a library in you application. This enables you to wire classes on the fly by its network dependency-aware classloading mechanisms. The library allows as well building solid and well integrated applications, mainly console applications. Indeed, nuts comes with rich outputs that support automatic formatting to json, xml, table, tree and plain texts. It handles standard File Systems layouts; XDG Base Directory Specification is implemented for linux and MacOS. A compatible one is also implemented in Windows systems. And of course, it helps seamlessly install, update and remove events.

Nuts ? Really ?​

In every palace you will find the wizard and the fool, the maven and the nuts; There's no exception in the java kingdom! If you do prefer acronyms here is another reason : nuts stands for Network Updatable Things Services. It should be able to facilitate things deployment and update over the wire where things resolve here to any piece of software depending (or not) on other piece of software.

Let's start the journey​

we start by opening a new terminal (termm, konsole or whatever you prefer) then download nuts using this command : On linux/MacOS system we issue :

wget https://github.com/thevpc/vpc-public-maven/raw/master/net/vpc/app/nuts/nuts/0.8.4/nuts-0.8.4.jar

Let's check that java is installed :

java --version

Now we run nuts

java -jar nuts-0.8.4.jar -zy

We used the flags -y to auto-confirm and -z to ignore cached binaries (combined here as -zy). These flags are not required. We use them here to make installation work in all cases. Installation may last several minutes as it will download all required dependencies, companions and tools.

You should then see this message

Welcome to nuts. Yeah, it is working...

nuts is well installed, just restart your terminal.

Now we will install apache tomcat. So in your terminal type:

nuts install ntomcat
nuts ntomcat start --set-port 9090

The first two commands will install tomcat helper tool (ntomcat) that will download latest version of tomcat and configure it to 9090 port. The last command will start tomcat. Let's check tomcat status now

nuts tomcat status

Now we will do the same with derby database. We will install it and run it.

nuts install nderby
nuts nderby start

As you can see, simple commands are all you need to download, install, configure and run tomcat or derby or any application that is deployed in the maven repository.

So please visit nuts website or github repository for more information.