Apache Karaf
Version 2.2.8










Apache Karaf
Users' Guide







Table of contents

  1. Overview
  2. Quick Start
  3. Users Guide
  4. Developers Guide

Overview

Karaf Overview

Apache Karaf is a small OSGi based runtime which provides a lightweight container onto which various components and applications can be deployed.

Here is a short list of features supported by the Karaf:

Quick Start

1. Quick Start

If you are in a hurry to have Apache Karaf up and running right away, this section will provide you with some basic steps for downloading, building (when needed) and running the server in no time. This is clearly not a complete guide so you may want to check other sections of this guide for further information.

All you need is 5 to 10 minutes and to follow these basic steps.

Background

Apache Karaf is a small and lightweight OSGi based runtime. This provides a small lightweight container onto which various bundles can be deployed.

Apache Karaf started life as the Apache ServiceMix kernel and then moved as a Apache Felix subproject before becoming a top level project.

Getting the software

At this time you have one option to get the software. The fastest and easiest way is to get the binary directly from the Apache site. Since this article is intended to help you to have Apache Karaf up and running in the fastest way only the binary download will be covered at this time.

Prerequisites

Although this installation path is the fastest one, you will still need to install some software before installing Karaf.

Karaf requires a Java SE 5 environment to run. Refer to http://www.oracle.com/technetwork/java/javase/ for details on how to download and install Java SE 1.5 or greater.

Download binaries

You will need to select the appropriate installation image for the platform you're using to run Karaf. Open a Web browser and access the following URL, there you will find the available packages for download (binaries and source code).

http://karaf.apache.org/index/community/download.html

Select the file compression format compatible with your system (zip for windows, tar.gz for unixes) by clicking directly on the link, download it and expand the binary to your hard drive in a new directory; for example in z:\karaf - from now on this directory will be referenced as <KARAF_HOME>. Please remember the restrictions concerning illegal characters in Java paths, e.g. !, % etc.

The installation of Karaf is as simple as uncompressing the .zip or .tar.gz files. The next step is to start the server.

Start the server

With Karaf already installed, open a command line console and change directory to <KARAF_HOME>. To start the server, run the following command in Windows:

bin\karaf.bat

respectively on Unix:

bin/karaf

You should see the following information on the command line console:

You can now run your first command. Simply type the <tab> key in the console.

karaf@root> 

admin:change-port         admin:connect             admin:create              admin:destroy
admin:list                admin:start               admin:stop                config:cancel
config:edit               config:list               config:propappend         config:propdel
config:proplist           config:propset            config:update             dev:dynamic-import
dev:framework             dev:print-stack-traces    dev:show-tree             features:addUrl
features:info             features:install          features:list             features:listUrl
features:refreshUrl       features:removeUrl        features:uninstall        log:display
log:display-exception     log:get                   log:set                   osgi:bundle-level
osgi:headers              osgi:install              osgi:list                 osgi:ls
osgi:refresh              osgi:resolve              osgi:restart              osgi:shutdown
osgi:start                osgi:start-level          osgi:stop                 osgi:uninstall
osgi:update               packages:exports          packages:imports          shell:cat
shell:clear               shell:each                shell:echo                shell:exec
shell:grep                shell:history             shell:if                  shell:info
shell:java                shell:logout              shell:new                 shell:printf
shell:sleep               shell:sort                shell:tac                 ssh:ssh
ssh:sshd                  cat                       clear                     each
echo                      exec                      grep                      history
if                        info                      java                      logout
new                       printf                    sleep                     sort
tac                       bundle-level              headers                   install
list                      ls                        refresh                   resolve
restart                   shutdown                  start                     start-level
stop                      uninstall                 update
karaf@root> 

You can then grab more specific help for a given command using the --help option for this command:

karaf@root> admin:create --help
DESCRIPTION
	admin:create

	Create a new instance.

SYNTAX
	admin:create [options] name

ARGUMENTS
        name
                The name of the new container instance

OPTIONS
        --help
                Display this help message
        -f, --feature
                Initial features. This option can be specified multiple times to enable multiple initial 
                features
        -p, --port
                Port number for remote shell connection
        -l, --location
                Location of the new container instance in the file system
        -furl, --featureURL
                Additional feature descriptor URLs. This option can be specified multiple times to add 
                multiple URLs

karaf@root> 

Note that the console supports tab completion, so you just need to enter ad <tab> cr <tab> instead of admin:create.

Deploy a sample application

While you will learn in the Karaf user's guide how to fully use and leverage Apache Karaf, let's install a sample Apache Camel application for now:

In the console, run the following commands:

features:addurl mvn:org.apache.camel/camel-example-osgi/2.7.0/xml/features
features:install camel-example-osgi

The example installed is using Camel to start a timer every 2 seconds and output a message on the console.
The previous commands download the Camel features descriptor and install the example feature.

>>>> SpringDSL set body:  Fri Jan 07 11:59:51 CET 2011
>>>> SpringDSL set body:  Fri Jan 07 11:59:53 CET 2011
>>>> SpringDSL set body:  Fri Jan 07 11:59:55 CET 2011

Stopping and uninstalling the sample application

To stop this demo, run the following command:

features:uninstall camel-example-osgi

Common Problems

  1. Launching Karaf can result in a deadlock in Felix during module dependency resolution.

    This is often a result of sending a SIGINT (control-C) to the process when it will not cleanly exit.
    This can corrupt the caches and cause startup problems in the very next launch. It is fixed by emptying the component cache:

    rm -rf data/cache/*
    

Stopping Karaf

To stop Karaf from the console, enter ^D in the console:

^D

Alternatively, you can also run the following command:

osgi:shutdown

Summary

This document showed how simple it is to have Apache Karaf up and running. The overall time for getting the server running should be less than five
minutes if you have the prerequisite (Java 1.5) already installed. Additionally, this article also showed you how to deploy and test a simple
Apache Camel application.

Users Guide

Installation

This chapter describes how to install Apache Karaf for both Unix and Windows platforms, including
prerequisite software and necessary download links.

Pre-Installation Requirements

Hardware:

Operating Systems:

Environment:

Building from Sources

If you intend to build Karaf from the sources, the requirements are a bit different:

Hardware:

Environment:

Building on Windows

This procedure explains how to download and install the source distribution on a Windows system. NOTE: Karaf requires Java 5 is compile, build and run.

  1. From a browser, navigate to http://karaf.apache.org/index/community/download.html.
  2. Scroll down to the "Apache Karaf" section and select the desired distribution.

    For a source distribution, the filename will be similar to: apache-karaf-x.y-src.zip.

  3. Extract Karaf from the ZIP file into a directory of your choice. Please remember the restrictions concerning illegal characters in Java paths, e.g. !, % etc.
  4. Build Karaf using Maven 2.2.1 or greater and Java 5.

    The recommended method of building Karaf is the following:

    cd [karaf_install_dir]\src
    

    where [karaf_install_dir] is the directory in which Karaf was installed.

    mvn
    

    Both steps take around 10 to 15 minutes.

  5. Unzip the distribution using your favorite zip tool. The windows distribution is available at
    [karaf_install_dir]\assembly\target\apache-karaf-x.y.zip
    
  6. Proceed to the Starting Karaf chapter.

Building on Unix

This procedure explains how to download and install the source distribution on a Unix system. This procedure assumes the Unix machine has a browser. Please see the previous Unix Binary Installation section for ideas on how to install Karaf without a browser. NOTE: Karaf requires Java 5 to compile, build and run.

  1. From a browser, navigate to http://karaf.apache.org/download.html.
  2. Scroll down to the "Apache Karaf" section and select the desired distribution.

    For a source distribution, the filename will be similar to: apache-karaf-x.y-src.tar.gz.

  3. Extract the files from the ZIP file into a directory of your choice. For example:
    gunzip apache-karaf-x.y-src.tar.gz
    tar xvf apache-karaf-x.y-src.tar
    

    Please remember the restrictions concerning illegal characters in Java paths, e.g. !, % etc.

  4. Build Karaf using Maven:

    The preferred method of building Karaf is the following:

    cd [karaf_install_dir]/src
    

    where [karaf_install_dir] is the directory in which Karaf was installed.

    mvn
    
  5. Uncompress the distribution that has just been created
    cd [karaf_install_dir]/assembly/target
    gunzip apache-karaf-x.y.tar.gz
    tar xvf apache-karaf-x.y.tar
    
  6. Proceed to the Starting Karaf chapter.

Installation Procedure for Windows

This procedure explains how to download and install the binary distribution on a Windows system.

  1. From a browser, navigate to http://karaf.apache.org/index/community/download.html.
  2. Scroll down to the "Apache Karaf" section and select the desired distribution.

    For a binary distribution, the filename will be similar to: apache-karaf-x.y.zip.

  3. Extract the files from the ZIP file into a directory of your choice. Please remember the restrictions concerning illegal characters in Java paths, e.g. !, % etc.
  4. Proceed to the Starting Karaf chapter.
  5. Optional: see enabling Colorized Console Output On Windows

Handy Hint

In case you have to install Karaf into a very deep path or a path containing illegal characters for Java paths, e.g. !, % etc., you may add a bat file to start \-> startup that executes

subst S: "C:\your very % problematic path!\KARAF"

so your Karaf root directory is S: - which works for sure and is short to type.

Installation Procedure For Unix

This procedure explains how to download and install the binary distribution on a Unix system.

  1. From a browser, navigate to http://karaf.apache.org/download.html.
  2. Scroll down to the "Apache Karaf" section and select the desired distribution.

    For a binary Unix distribution, the filename will be similar to: apache-karaf-x.y.tar.gz.

  3. Extract the files from the gzip file into a directory of your choice. For example:
    gunzip apache-karaf-x.y.tar.gz
    tar xvf apache-karaf-x.y.tar
    

    Please remember the restrictions concerning illegal characters in Java paths, e.g. !, % etc.

  4. Proceed to the Starting Karaf chapter.

Post-Installation steps

Thought it is not always required, it is strongly advised to set up the JAVA_HOME environment property to point to the JDK you want Karaf to use before starting it.
This property is used to locate the java executable and should be configured to point to the home directory of the Java SE 5 or 6 installation.

Directory structure

The directory layout of a Karaf installation is as follows:

The data folder contains all the working and temporary files for Karaf. If you want to restart from a clean state, you can wipe out this directory, which has the same effect as using the clean option.

Starting and Stopping Karaf

This chapter describes how to start and stop Apache Karaf and the various options that are available.

Starting Karaf

On Windows

From a console window, change to the installation directory and run Karaf. For the binary distribution, go to

cd [karaf_install_dir]

where karaf_install_dir is the directory in which Karaf was installed, e.g., c:\Program Files\apache-karaf-x.y.

Then type:

bin\karaf.bat

On Unix

From a command shell, change to the installation directory and run Karaf. For the binary distribution, go to

cd [karaf_install_dir]

where karaf_install_dir is the directory in which Karaf was installed, e.g., /usr/local/apache-karaf-x.y.

Then type:

bin/karaf

Warning

Do NOT close the console or shell in which Karaf was started, as that will terminate Karaf (unless Karaf was started with nohup).

Starting Karaf without console

Karaf can be started without the console if you don't intend to use it (one can always connect using the remote ssh access) using the following command:

bin\karaf.bat server

or, on Unix:

bin\karaf server

Starting Karaf in the background

Karaf can be easily started as a background process using the following command:

bin\start.bat

or, on Unix:

bin\start

Starting Karaf from clean

Karaf can be reset to a clean state by simply deleting the [karaf_install_dir]/data folder.
For convenience, a parameter on the karaf and start scripts is available:

bin/start clean

Stopping Karaf

For both Windows and Unix installations, you can perform a clean shutdown of Karaf by using the following command when inside a Karaf console:

osgi:shutdown

or simply:

shutdown

The shutdown command asks you to confirm that you really want to shutdown. If you are sure about the shutdown and avoid the confirmation message, you can use the -f or --force option:

osgi:shutdown -f

It's also possible to delay the shutdown using the time argument. The time argument can have different formats. First, it can be an absolute time in the format hh:mm, in which hh is the hour (1 or 2 digits) and mm is the minute of the hour (in two digits). Second, it can be in the format +m, in which m is the number of minutes to wait. The work now is an alias for +0.

The following command will shutdown Karaf at 10:35am:

osgi:shutdown 10:35

The following command will shutdown Karaf in 10 minutes:

osgi:shutdown +10

If you're running from the main console, exiting the shell using logout or Ctrl+D will also terminate the Karaf instance.

From a command shell, you can run the following command:

bin\stop.bat

or, on Unix:

bin/stop

Service Wrapper

Introduction

The Karaf Wrapper (for service wrapper) makes it possible to install Karaf as a Windows Service. Likewise, the scripts shipped with Karaf also make it very easy to install Karaf as a daemon process on Unix systems.

The Wrapper correctly handles "user's log outs" under Windows, service dependencies, and the ability to run services which interact with the desktop.

Supported platforms

The following platforms are supported by the Karaf Wrapper:

Installation

Karaf Wrapper is an optional feature. To install it, simply type:

karaf@root> features:install wrapper

Once installed, wrapper feature will provide wrapper:install new command in the Karaf shell:

karaf@root> wrapper:install --help
DESCRIPTION
        wrapper:install

        Install the container as a system service in the OS.

SYNTAX
        wrapper:install [options]

OPTIONS
        -s, --start-type
                Mode in which the service is installed. AUTO_START or DEMAND_START (Default: AUTO_START)
                (defaults to AUTO_START)
        --help
                Display this help message
        -n, --name
                The service name that will be used when installing the service. (Default: karaf)
                (defaults to karaf)
        -d, --display
                The display name of the service.
        -D, --description
                The description of the service.
                (defaults to )

Using wrapper:install, you can install Karaf as a service.

For instance, to register Karaf as a service (depending of the running OS), in automatic start mode, simply type:

karaf@root> wrapper:install -s AUTO_START -n KARAF -d Karaf -D "Karaf Service"

For instance, on Linux, wrapper:install command will do:

karaf@root> wrapper:install -s AUTO_START -n KARAF -d Karaf -D "Karaf Service"
Creating file: /home/onofreje/apache-karaf-2.1.3/bin/KARAF-wrapper
Creating file: /home/onofreje/apache-karaf-2.1.3/bin/KARAF-service
Creating file: /home/onofreje/apache-karaf-2.1.3/etc/KARAF-wrapper.conf
Creating file: /home/onofreje/apache-karaf-2.1.3/lib/libwrapper.so
Creating file: /home/onofreje/apache-karaf-2.1.3/lib/karaf-wrapper.jar
Creating file: /home/onofreje/apache-karaf-2.1.3/lib/karaf-wrapper-main.jar

Setup complete.  You may wish to tweak the JVM properties in the wrapper configuration file:
        /home/onofreje/apache-karaf-2.1.3/etc/KARAF-wrapper.conf
before installing and starting the service.

The way the service is installed depends upon your flavor of Linux.

On Redhat/Fedora/CentOS Systems:
  To install the service:
    $ ln -s /home/onofreje/apache-karaf-2.1.3/bin/KARAF-service /etc/init.d/
    $ chkconfig KARAF-service --add

  To start the service when the machine is rebooted:
    $ chkconfig KARAF-service on

  To disable starting the service when the machine is rebooted:
    $ chkconfig KARAF-service off

  To start the service:
    $ service KARAF-service start

  To stop the service:
    $ service KARAF-service stop

  To uninstall the service :
    $ chkconfig KARAF-service --del
    $ rm /etc/init.d/KARAF-service

On Ubuntu/Debian Systems:
  To install the service:
    $ ln -s /home/onofreje/apache-karaf-2.1.3/bin/KARAF-service /etc/init.d/

  To start the service when the machine is rebooted:
    $ update-rc.d KARAF-service defaults

  To disable starting the service when the machine is rebooted:
    $ update-rc.d -f KARAF-service remove

  To start the service:
    $ /etc/init.d/KARAF-service start

  To stop the service:
    $ /etc/init.d/KARAF-service stop

  To uninstall the service :
    $ rm /etc/init.d/KARAF-service

Using the console

Viewing available commands

To see a list of the available commands in the console press the <tab> key at the prompt.

root@root> Display all 182 possibilities? (y or n)
*:help                           addurl                           admin:change-opts
admin:change-rmi-registry-port   admin:change-ssh-port            admin:connect
admin:create                     admin:destroy                    admin:list
admin:rename                     admin:start                      admin:stop
bundle-level                     cancel                           cat
change-opts                      change-rmi-registry-port         change-ssh-port
clear                            commandlist                      config:cancel
config:edit                      config:list                      config:propappend
config:propdel                   config:proplist                  config:propset
config:update                    connect                          create
create-dump                      destroy                          dev:create-dump
dev:dynamic-import               dev:framework                    dev:print-stack-traces
dev:restart                      dev:show-tree                    dev:watch
display                          display-exception                dynamic-import
each                             echo                             edit
exec                             exports                          features:addurl
features:info                    features:install                 features:list
features:listrepositories        features:listurl                 features:listversions
features:refreshurl              features:removerepository        features:removeurl
features:uninstall               framework                        get
grep                             head                             headers
help                             history                          if
imports                          info                             install
jaas:cancel                      jaas:commandlist                 jaas:list
jaas:manage                      jaas:roleadd                     jaas:roledel
jaas:update                      jaas:useradd                     jaas:userdel
jaas:userlist                    java                             list
listrepositories                 listurl                          listversions
log:clear                        log:display                      log:display-exception
log:get                          log:set                          log:tail
logout                           ls                               manage
more                             new                              osgi:bundle-level
osgi:headers                     osgi:info                        osgi:install
osgi:list                        osgi:ls                          osgi:refresh
osgi:resolve                     osgi:restart                     osgi:shutdown
osgi:start                       osgi:start-level                 osgi:stop
osgi:uninstall                   osgi:update                      packages:exports
packages:imports                 print-stack-traces               printf
propappend                       propdel                          proplist
propset                          refresh                          refreshurl
removerepository                 removeurl                        rename
resolve                          restart                          roleadd
roledel                          set                              shell:cat
shell:clear                      shell:each                       shell:echo
shell:exec                       shell:grep                       shell:head
shell:history                    shell:if                         shell:info
shell:java                       shell:logout                     shell:more
shell:new                        shell:printf                     shell:sleep
shell:sort                       shell:tac                        shell:tail
show-tree                        shutdown                         sleep
sort                             ssh                              ssh:ssh
ssh:sshd                         sshd                             start
start-level                      stop                             tac
tail                             uninstall                        update
useradd                          userdel                          userlist
watch
root@root>

The <tab> key toggles autocompletion anywhere on the line, so if you want to see the commands in the osgi group, type the first letters and hit <tab>. Depending on the commands, autocompletion may be available for options and arguments too.

Getting help for a command

To view help on a particular command, type the command followed by --help or use the help command followed by the name of the command:

karaf@root> features:list --help
DESCRIPTION
        features:list

        Lists all existing features available from the defined repositories.

SYNTAX
        features:list [options]

OPTIONS
        --help
                       Display this help message
        -i, --installed
                       Display a list of all installed features only

More...

The list of all available commands and their usage is also available in a dedicated section.

You'll find a more in-depth guide to the shell syntax in the developers guide.

The console can also be easily extended by creating new commands as explained in the developers guide.

Enabling Colorized Console on Windows

The default Karaf installation does not produce colorized console output on Windows like it does on Unix based systems. To enable it, you must install LGPL licensed library JNA. This can be done using a few simple commands in the Karaf console:

You first need to install the JNA library:

karaf@root> osgi:install wrap:mvn:http://download.java.net/maven/2!net.java.dev.jna/jna/3.1.0

Next you need either restart karaf or you run the following Karaf commands to refresh the Karaf Console:

karaf@root> osgi:list | grep "Apache Karaf :: Shell Console"

Take note of the ID of the bundle, in my case it was 14 and then run:

osgi:refresh 14

TODO: refactor that using a nicer script to find the correct bundle

Using remote instances

Configuring remote instances

It does not always make sense to manage an instance of Karaf using its local console. You can manage Karaf remotely using a remote console.

When you start Karaf, it enables a remote console that can be accessed over SSH from any other Karaf console or plain SSH client. The remote console provides all the features of the local console and gives a remote user complete control over the container and services running inside of it.

The SSH hostname and port number is configured in the [karaf_install_dir]/etc/org.apache.karaf.shell.cfg configuration file with the following default values:

sshPort=8101
sshHost=0.0.0.0
sshRealm=karaf
hostKey=${karaf.base}/etc/host.key

You can change this configuration using the config commands or by editing the above file, but you'll need to restart the ssh console in order for it to use the new parameters.

# define helper functions
bundle-by-sn = { bm = new java.util.HashMap ;  each (bundles) { $bm put ($it symbolicName) $it } ; $bm get $1 }
bundle-id-by-sn = { b = (bundle-by-sn $1) ; if { $b } { $b bundleId } { -1 } }
# edit config
config:edit org.apache.karaf.shell
config:propset sshPort 8102
config:update 
# force a restart
osgi:restart --force (bundle-id-by-sn org.apache.karaf.shell.ssh)

Connecting and disconnecting remotely

Using the ssh:ssh command

You can connect to a remote Karaf's console using the ssh:ssh command.

karaf@root> ssh:ssh -l karaf -P karaf -p 8101 hostname

The default password is karaf but we recommend changing it. See the security section for more informations.

To confirm that you have connected to the correct Karaf instance, type shell:info at the karaf> prompt. Information about the currently connected instance is returned, as shown.

Karaf
  Karaf home                  /local/apache-karaf-2.0.0
  Karaf base                  /local/apache-karaf-2.0.0
  OSGi Framework              org.eclipse.osgi - 3.5.1.R35x_v20090827
JVM
  Java Virtual Machine        Java HotSpot(TM) Server VM version 14.1-b02
  ...

Using the Karaf client

The Karaf client allows you to securely connect to a remote Karaf instance without having to launch a Karaf instance locally.

For example, to quickly connect to a Karaf instance running in server mode on the same machine, run the following command from the karaf-install-dir directory:

bin/client

More commonly, you would provide a hostname, port, username and password to connect to a remote instance. And, if you were using the client within a larger script, you could append console commands as follows:

bin/client -a 8101 -h hostname -u karaf -p karaf features:install wrapper

To display the available options for the client, type:

> bin/client --help
Apache Karaf client
  -a [port]     specify the port to connect to
  -h [host]     specify the host to connect to
  -u [user]     specify the user name
  -p [password] specify the password
  --help        shows this help message
  -v            raise verbosity
  -r [attempts] retry connection establishment (up to attempts times)
  -d [delay]    intra-retry delay (defaults to 2 seconds)
  [commands]    commands to run
If no commands are specified, the client will be put in an interactive mode

Using a plain SSH client

You can also connect using a plain SSH client from your *nix system or Windows SSH client like Putty.

~$ ssh -p 8101 karaf@localhost
karaf@localhost's password: 

Disconnecting from a remote console

To disconnect from a remote console, press Ctrl+D, shell:logout or simply logout at the Karaf prompt.

Stopping a remote instance

Using the remote console

If you have connected to a remote console using the ssh:ssh command or the Karaf client, you can stop the remote instance using the osgi:shutdown command.

Pressing Ctrl+D in a remote console simply closes the remote connection and returns you to the local shell.

Using the Karaf client

To stop a remote instance using the Karaf client, run the following from the karaf-install-dir/lib directory:

bin/client -u karaf -p karaf -a 8101 hostname osgi:shutdown

Web console

The Karaf web console provides a graphical overview of the runtime.
You can use it to:

Installing the web console

The web console is not installed by default. To install it, run the following command from the Karaf prompt:

root@karaf> features:install webconsole

Accessing the web console

To access the console for an instance of Karaf running locally, enter the following address in your web browser:

http://localhost:8181/system/console

Log in with the username karaf and the password karaf. If you have changed the default user or password, use the one you have configured.

Changing the web console port number

By default, the console runs on port 8181. You can change the port number by creating the properties file, etc/org.ops4j.pax.web.cfg, and adding the following property setting (changing the port number to whatever value desired):

org.osgi.service.http.port=8181

Managing child instances

A child instance of Karaf is a copy that you can launch separately and deploy applications into. An instance does not contain the full copy of Karaf, but only a copy of the configuration files and data folder which contains all the runtime information, logs and temporary files.

Using the admin console commands

The admin console commands allow you to create and manage instances of Karaf on the same machine. Each new runtime is a child instance of the runtime that created it. You can easily manage the children using names instead of network addresses. For details on the admin commands, see the admin commands.

Creating child instances

You create a new runtime instance by typing admin:create in the Karaf console.

As shown in the following example, admin:create causes the runtime to create a new runtime installation in the active runtime's {{instances/name} directory. The new instance is a new Karaf instance and is assigned an SSH port number based on an incremental count starting at 8101 and a RMI registry port number based on an incremental count starting at 1099/44444.

karaf@root> admin:create alpha 
Creating new instance on SSH port 8102 and RMI ports 1100/44445 at: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha
Creating dir:  /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/bin
Creating dir:  /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc
Creating dir:  /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/system
Creating dir:  /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/deploy
Creating dir:  /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/data
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/config.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/jre.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/custom.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/java.util.logging.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.apache.felix.fileinstall-deploy.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.apache.karaf.log.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.apache.karaf.features.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.ops4j.pax.logging.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.ops4j.pax.url.mvn.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/startup.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/users.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/system.properties
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.apache.karaf.shell.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/etc/org.apache.karaf.management.cfg
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/bin/karaf
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/bin/start
Creating file: /x3/karaf/test/apache-karaf-2.2.4/instances/alpha/bin/stop
karaf@root>

Changing a child's ports

You can change the SSH port number assigned to a child instance using the admin:change-ssh-port command. The syntax for the command is:

admin:change-ssh-port instance port

Note that the child instance has to be stopped in order to run this command.

In the same way, you can change the RMI registry port number assigned to a child instance using the admin:change-rmi-registry-port command. The syntax for the command is:

admin:change-rmi-registry-port instance port

Note that the child instance has to be stopped in order to run this command.

Starting child instances

New instances are created in a stopped state. To start a child instance and make it ready to host applications, use the admin:start command. This command takes a single argument instance-name that identifies the child you want started.

Listing all container instances

To see a list of all Karaf instances running under a particular installation, use the admin:list command.

karaf@root>admin:list
  SSH Port   RMI Port   State       Pid  Name
[    8107] [      1106] [Started ] [10628] harry
[    8101] [      1099] [Started ] [20076] root
[    8106] [      1105] [Stopped ] [15924] dick
[    8105] [      1104] [Started ] [18224] tom
karaf@root>

Connecting to a child instance

You can connect to a started child instance's remote console using the admin:connect command which takes three arguments:

admin:connect [-u username] [-p password] instance 

Once you are connected to the child instance, the Karaf prompt changes to display the name of the current instance, as shown:

karaf@harry>

Stopping a child instance

To stop a child instance from within the instance itself, type osgi:shutdown or simply shutdown.

To stop a child instance remotely, in other words, from a parent or sibling instance, use the admin:stop:

admin:stop instance

Destroying a child instance

You can permanently delete a stopped child instance using the admin:destroy command:

admin:destroy instance

Note that only stopped instances can be destroyed.

Using the admin script

You can also manage the local instances of Karaf. The admin script in the karaf-install-dir/bin directory provides the same commands as the admin console commands, apart from admin:connect.

> bin/admin
Available commands:
  change-ssh-port - Changes the secure shell port of an existing container instance.
  change-rmi-registry-port - Changes the RMI registry port (used by management layer) of an existing container instance.
  create - Creates a new container instance.
  destroy - Destroys an existing container instance.
  list - List all existing container instances.
  start - Starts an existing container instance.
  stop - Stops an existing container instance.
Type 'command --help' for more help on the specified command.

For example, to list all the instances of Karaf on the local machine, type:

bin/admin list

Security

Managing users and passwords

The default security configuration uses a property file located at karaf-install-dir/etc/users.properties to store authorized users and their passwords.

The default user name is karaf and the associated password is karaf too. We strongly encourage you to change the default password by editing the above file before moving Karaf into production.

The users are currently used in three different places in Karaf:

Managing roles

JAAS roles can be used by various components. The three management layers (SSH, JMX and WebConsole) all use a global role based authorization system. The default role name is configured in the etc/system.properties using the karaf.admin.role system property and the default value is admin. All users authenticating for the management layer must have this role defined.

The syntax for this value is the following:

[classname:]principal

where classname is the class name of the principal object (defaults to org.apache.karaf.jaas.modules.RolePrincipal) and principal is the name of the principal of that class (defaults to admin).

Note that roles can be changed for a given layer using ConfigAdmin in the following configurations:

Layer PID Value
SSH org.apache.karaf.shell sshRole
JMX org.apache.karaf.management jmxRole
Web org.apache.karaf.webconsole role

Enabling password encryption

In order to not keep the passwords in plain text, the passwords can be stored encrypted in the configuration file.
This can be easily enabled using the following commands:

# edit config
config:edit org.apache.karaf.jaas
config:propset encryption.enabled true
config:update 
# force a restart
dev:restart

The passwords will be encrypted automatically in the etc/users.properties configuration file the first time the user logs in.
Encrypted passwords are prepended with {CRYPT} so that are easy to recognize.

Managing realms

More information about modifying the default realm or deploying new realms is provided in the developers guide.

Deploying security providers

Some applications require specific security providers to be available, such as BouncyCastle. The JVM impose some restrictions about the use of such jars: they have to be signed and be available on the boot classpath. One way to deploy those providers is to put them in the JRE folder at $JAVA_HOME/jre/lib/ext and modify the security policy configuration ($JAVA_HOME/jre/lib/security/java.security) in order to register such providers.

While this approach works fine, it has a global effect and requires you to configure all your servers accordingly.

Karaf offers a simple way to configure additional security providers:

org.apache.karaf.security.providers = xxx,yyy

The value of this property is a comma separated list of the provider class names to register.
For example:

org.apache.karaf.security.providers = org.bouncycastle.jce.provider.BouncyCastleProvider

In addition, you may want to provide access to the classes from those providers from the system bundle so that all bundles can access those. It can be done by modifying the org.osgi.framework.bootdelegation property in the same configuration file:

org.osgi.framework.bootdelegation = ...,org.bouncycastle*

Failover Deployments

Karaf provides failover capability using either a simple lock file system or a JDBC locking mechanism. In both cases, a container-level lock system allows bundles to be preloaded into the slave Karaf instance in order to provide faster failover performance.

Simple lock file

The simple lock file mechanism is intended for failover configurations where instances reside on the same host machine.

To use this feature, edit the $KARAF_HOME/etc/system.properties file as follows on each system in the master/slave setup:

karaf.lock=true
karaf.lock.class=org.apache.karaf.main.SimpleFileLock
karaf.lock.dir=<PathToLockFileDirectory>
karaf.lock.delay=10

Note: Ensure that the karaf.lock.dir property points to the same directory for both the master and slave instance, so that the slave can acquire the lock only when the master releases it.

JDBC locking

The JDBC locking mechanism is intended for failover configurations where instances exist on separate machines. In this deployment, the master instance holds a lock on a Karaf locking table hosted on a database. If the master loses the lock, a waiting slave process gains access to the locking table and fully starts its container.

To use this feature, do the following on each system in the master/slave setup:

karaf.lock=true
karaf.lock.class=org.apache.karaf.main.DefaultJDBCLock
karaf.lock.level=50
karaf.lock.delay=10
karaf.lock.jdbc.url=jdbc:derby://dbserver:1527/sample
karaf.lock.jdbc.driver=org.apache.derby.jdbc.ClientDriver
karaf.lock.jdbc.user=user
karaf.lock.jdbc.password=password
karaf.lock.jdbc.table=KARAF_LOCK
karaf.lock.jdbc.clustername=karaf
karaf.lock.jdbc.timeout=30

Note:

JDBC locking on Oracle

If you are using Oracle as your database for JDBC locking, the karaf.lock.class property in the $KARAF_HOME/etc/system.properties file must point to org.apache.karaf.main.OracleJDBCLock.

Otherwise, configure the system.properties file as normal for your setup, for example:

karaf.lock=true
karaf.lock.class=org.apache.karaf.main.OracleJDBCLock
karaf.lock.jdbc.url=jdbc:oracle:thin:@hostname:1521:XE
karaf.lock.jdbc.driver=oracle.jdbc.OracleDriver
karaf.lock.jdbc.user=user
karaf.lock.jdbc.password=password
karaf.lock.jdbc.table=KARAF_LOCK
karaf.lock.jdbc.clustername=karaf
karaf.lock.jdbc.timeout=30

As with the default JDBC locking setup, the Oracle JDBC driver JAR file must be in your classpath. You can ensure this by copying the ojdbc14.jar into Karaf's lib folder before starting Karaf.

Note: The karaf.lock.jdbc.url requires an active SID, which means you must manually create a database instance before using this particular lock.

Derby

TODO

MySQL

TODO

Container-level locking

Container-level locking allows bundles to be preloaded into the slave kernel instance in order to provide faster failover performance. Container-level locking is supported in both the simple file and JDBC locking mechanisms.

To implement container-level locking, add the following to the $KARAF_HOME/etc/system.properties file on each system in the master/slave setup:

karaf.lock=true
karaf.lock.level=50
karaf.lock.delay=10

The karaf.lock.level property tells the Karaf instance how far into the boot process to bring the OSGi container. All bundles with an ID equal or lower to this start level will be started in that Karaf instance.

Bundle start levels are specified in $KARAF_HOME/etc/startup.properties, in the format jar.name=level. The core system bundles have levels below 50, where user bundles have levels greater than 50.

Level Behavior
1 A 'cold' standby instance. Core bundles are not loaded into container. Slaves will wait until lock acquired to start server.
<50 A 'hot' standby instance. Core bundles are loaded into the container. Slaves will wait until lock acquired to start user level bundles. The console will be accessible for each slave instance at this level.
>50 This setting is not recommended as user bundles will end up being started.

Note: When using a 'hot' spare on the same host you need to set the JMX remote port to a unique value to avoid bind conflicts. You can edit the Karaf start script to include the following:

DEFAULT_JAVA_OPTS="-server $DEFAULT_JAVA_OPTS -Dcom.sun.management.jmxremote.port=1100 -Dcom.sun.management.jmxremote.authenticate=false"

Logging system

Karaf provides a powerful logging system based on OPS4j Pax Logging.

In addition to being a standard OSGi Log service, it supports the following APIs:

Karaf also comes with a set of console commands that can be used to display, view and change the log levels.

Configuration

Configuration file

The configuration of the logging system uses a standard Log4j configuration file at the following location:

[karaf_install_dir]/etc/org.ops4j.pax.logging.cfg

You can edit this file at runtime and any change will be reloaded and be effective immediately.

Configuring the appenders

The default logging configuration defines three appenders:

Changing the log levels

The default logging configuration sets the logging levels so that the log file will provide enough information to monitor the behavior of the runtime and provide clues about what caused a problem. However, the default configuration will not provide enough information to debug most problems.

The most useful logger to change when trying to debug an issue with Karaf is the root logger. You will want to set its logging level to DEBUG in the org.ops4j.pax.logging.cfg file.


log4j.rootLogger=DEBUG, out, osgi:VmLogAppender
...

When debugging a problem in Karaf you may want to change the level of logging information that is displayed on the console. The example below shows how to set the root logger to DEBUG but limiting the information displayed on the console to WARN.


log4j.rootLogger=DEBUG, out, stdout, osgi:VmLogAppender
log4j.appender.stdout.threshold=WARN
...

Console Log Commands

The log subshell comes with the following commands:

For example, if you want to debug something, you might want to run the following commands:

> log:set DEBUG
... do something ...
> log:display

Note that the log levels set using the log:set commands are not persistent and will be lost upon restart.
To configure those in a persistent way, you should edit the configuration file mentioned above using the config commands or directly using a text editor of your choice.

The log commands has a separate configure file:

[karaf_install_dir]/etc/org.apache.karaf.log.cfg

Advanced configuration

The logging backend uses Log4j, but offer a number of additional features.

Nested filters, appenders and error handlers

Filters

Appender filters can be added using the following syntax:


log4j.appender.[appender-name].filter.[filter-name]=[filter-class]
log4j.appender.[appender-name].filter.[filter-name].[option]=[value]

Below is a real example:


log4j.appender.out.filter.f1=org.apache.log4j.varia.LevelRangeFilter
log4j.appender.out.filter.f1.LevelMax=FATAL
log4j.appender.out.filter.f1.LevelMin=DEBUG

Nested appenders

Nested appenders can be added using the following syntax:


log4j.appender.[appender-name].appenders=[comma-separated-list-of-appender-names]

Below is a real example:


log4j.appender.async=org.apache.log4j.AsyncAppender
log4j.appender.async.appenders=jms

log4j.appender.jms=org.apache.log4j.net.JMSAppender
...

Error handlers

Error handlers can be added using the following syntax:


log4j.appender.[appender-name].errorhandler=[error-handler-class]
log4j.appender.[appender-name].errorhandler.root-ref=[true|false]
log4j.appender.[appender-name].errorhandler.logger-ref=[logger-ref]
log4j.appender.[appender-name].errorhandler.appender-ref=[appender-ref]

OSGi specific MDC attributes

Pax-Logging provides the following attributes by default:

An MDC sifting appender is available to split the log events based on MDC attributes. Below is a configuration example for this appender:


log4j.appender.sift=org.apache.log4j.sift.MDCSiftingAppender
log4j.appender.sift.key=bundle.name
log4j.appender.sift.default=karaf
log4j.appender.sift.appender=org.apache.log4j.FileAppender
log4j.appender.sift.appender.layout=org.apache.log4j.PatternLayout
log4j.appender.sift.appender.layout.ConversionPattern=%d{ABSOLUTE} | %-5.5p | %-16.16t | %-32.32c{1} | %-32.32C %4L | %m%n
log4j.appender.sift.appender.file=${karaf.data}/log/$\\{bundle.name\\}.log
log4j.appender.sift.appender.append=true

Enhanced OSGi stack trace renderer

This renderer is configured by default in Karaf and will give additional informations when printing stack traces.
For each line of the stack trace, it will display OSGi specific informations related to the class on that line: the bundle id, the bundle symbolic name and the bundle version. This information can greatly help diagnosing problems in some cases.
The information is appended at the end of each line in the following format id:name:version as shown below


java.lang.IllegalArgumentException: Command not found:  *:foo
	at org.apache.felix.gogo.runtime.shell.Closure.execute(Closure.java:225)[21:org.apache.karaf.shell.console:2.1.0]
	at org.apache.felix.gogo.runtime.shell.Closure.executeStatement(Closure.java:162)[21:org.apache.karaf.shell.console:2.1.0]
	at org.apache.felix.gogo.runtime.shell.Pipe.run(Pipe.java:101)[21:org.apache.karaf.shell.console:2.1.0]
	at org.apache.felix.gogo.runtime.shell.Closure.execute(Closure.java:79)[21:org.apache.karaf.shell.console:2.1.0]
	at org.apache.felix.gogo.runtime.shell.CommandSessionImpl.execute(CommandSessionImpl.java:71)[21:org.apache.karaf.shell.console:2.1.0]
	at org.apache.karaf.shell.console.jline.Console.run(Console.java:169)[21:org.apache.karaf.shell.console:2.1.0]
	at java.lang.Thread.run(Thread.java:637)[:1.6.0_20]

Using your own appenders

If you plan to use your own appenders, you need to create an OSGi bundle and attach it as a fragment to the bundle with a symbolic name of
org.ops4j.pax.logging.pax-logging-service. This way, the underlying logging system will be able to see and use your appenders.

So for example you write a log4j appender:
class MyAppender extends AppenderSkeleton {
...
}

Then you need to package the appender in a jar with a Manifest like this:

Manifest:
Bundle-SymbolicName: org.mydomain.myappender
Fragment-Host: org.ops4j.pax.logging.pax-logging-service
...

Copy the new appender fragment into the ${karaf.home}/system directory. Karaf uses a virtual maven repository to access resources in the system
directory, so the jar path should use the standard maven groupId/artifactId/version/ convention, where the groupId is a directory structure.

Edit ${karaf.home}/etc/startup.properties and add the new fragment bundle to the list before the pax-logging-service bundle.

Restart karaf with a clean run to reload the system bundles, and now you can use the appender in your log4j config file like shown in the config
examples above.

Deployer

The following picture describes the architecture of the deployer.

Blueprint deployer

Karaf includes a deployer that is able to deploy plain blueprint configuration files.
The deployer will transform on the fly any spring configuration file dropped into the deploy folder into a valid OSGi bundle.

The generated OSGi manifest will contain the following headers:

Manifest-Version: 2
Bundle-SymbolicName: [name of the file]
Bundle-Version: [version of the file]
Import-Package: [required packages]
DynamicImport-Package: *

The name and version of the file are extracted using a heuristic that will match common patterns. For example my-config-1.0.1.xml will lead to name = my-config and version = 1.0.1.
The default imported packages are extracted from the spring file definition and includes all classes referenced directly.

If you need to customize the generated manifest, you can do so by including an xml element in your blueprint configuration:

<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0">
  <manifest xmlns="http://karaf.apache.org/xmlns/deployer/blueprint/v1.0.0">
    Require-Bundle= my-bundle
  </manifest>

Spring deployer

Similar to the blueprint deployer, you can deploy spring-dm configuration files.

The generated OSGi manifest will contain the following headers:

Manifest-Version: 2
Bundle-SymbolicName: [name of the file]
Bundle-Version: [version of the file]
Spring-Context: *;publish-context:=false;create-asynchronously:=true
Import-Package: [required packages]
DynamicImport-Package: *

If you need to customize the generated manifest, you can do so by including an xml element in your spring configuration:

<spring:beans ...>
  <manifest xmlns="http://karaf.apache.org/xmlns/deployer/spring/v1.0.0">
    Require-Bundle= my-bundle
  </manifest>

Features deployer

To be able to hot deploy features from the deploy folder, you can just drop a feature descriptor on that folder. A bundle will be created and its installation (automatic) will trigger the installation of all features contained in the descriptor. Removing the file from the deploy folder will uninstall the features.
If you want to install a single feature, you can do so by writing a feature descriptor like the following:

<features>
  <repository>mvn:org.apache.servicemix.nmr/apache-servicemix-nmr/1.0.0/xml/features</repository>
  <feature name="nmr-only">
    <feature>nmr</feature>
  </feature>
</features>

For more informations about features, see the provisioning section.

War deployer

To be able to hot deploy web application (war) from the deploy folder, you have to install the war feature:

karaf@root> features:install war

NB: you can use the -v or --verbose option to see exactly what is performed by the feature deployer.

karaf@root> features:install -v war
Installing feature war 2.1.99-SNAPSHOT
Installing feature http 2.1.99-SNAPSHOT
Installing feature jetty 7.2.2.v20101205
Installing bundle mvn:org.apache.geronimo.specs/geronimo-servlet_2.5_spec/1.1.2
Found installed bundle: org.apache.servicemix.bundles.asm [9]
Installing bundle mvn:org.eclipse.jetty/jetty-util/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-io/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-http/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-continuation/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-server/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-security/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-servlet/7.2.2.v20101205
Installing bundle mvn:org.eclipse.jetty/jetty-xml/7.2.2.v20101205
Checking configuration file mvn:org.apache.karaf/apache-karaf/2.1.99-SNAPSHOT/xml/jettyconfig
Installing bundle mvn:org.ops4j.pax.web/pax-web-api/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-spi/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-runtime/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-jetty/1.0.0
Installing bundle mvn:org.apache.karaf.shell/org.apache.karaf.shell.web/2.1.99-SNAPSHOT
Installing bundle mvn:org.ops4j.pax.web/pax-web-jsp/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-extender-war/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-extender-whiteboard/1.0.0
Installing bundle mvn:org.ops4j.pax.web/pax-web-deployer/1.0.0
Installing bundle mvn:org.ops4j.pax.url/pax-url-war/1.2.5

As you can see, the war feature uses PAX Web as war deployer.

You should now be able to see the PAX Web war deployer:

karaf@root> osgi:list |grep -i war
[  57] [Active     ] [            ] [   60] OPS4J Pax Web - Extender - WAR (1.0.0)
[  60] [Active     ] [            ] [   60] OPS4J Pax Url - war:, war-i: (1.2.5)

You can deploy a web application packaged in war or exploded in a directory.

Your web application should at least contain a WEB-INF/web.xml file.

Wrap deployer

The wrap deployer allows you to hot deploy non-OSGi jar files ("classical" jar files) from the deploy folder.

It's a standard deployer (you don't need to install additional Karaf features):

karaf@root> la|grep -i wrap
[   1] [Active     ] [            ] [    5] OPS4J Pax Url - wrap: (1.2.5)
[  32] [Active     ] [Created     ] [   30] Apache Karaf :: Deployer :: Wrap Non OSGi Jar (2.1.99.SNAPSHOT)

Karaf wrap deployer looks for jar files in the deploy folder. The jar files is considered as non-OSGi if the MANIFEST
doesn't contain the Bundle-SymbolicName and Bundle-Version attributes, or if there is no MANIFEST at all.

The non-OSGi jar file is transformed into an OSGi bundle.

The deployer tries to populate the Bundle-SymbolicName and Bundle-Version extracted from the jar file path.

For example, if you simply copy commons-lang-2.3.jar (which is not an OSGi bundle) into the deploy folder, you
will see:

karaf@root> la|grep -i commons-lang
[  41] [Active     ] [            ] [   60] commons-lang (2.3)

If you take a look on the commons-lang headers, you can see that the bundle exports all packages with optional resolution
and that Bundle-SymbolicName and Bundle-Version have been populated:

karaf@root> osgi:headers 41

commons-lang (41)
-----------------
Specification-Title = Commons Lang
Tool = Bnd-0.0.357
Specification-Version = 2.3
Specification-Vendor = Apache Software Foundation
Implementation-Version = 2.3
Generated-By-Ops4j-Pax-From = wrap:file:/home/onofreje/workspace/karaf/assembly/target/apache-karaf-2.99.99-SNAPSHOT/deploy/commons-lang-2.3.jar$Bundle-SymbolicName=commons-lang&Bundle-Version=2.3
Implementation-Vendor-Id = org.apache
Created-By = 1.6.0_21 (Sun Microsystems Inc.)
Implementation-Title = Commons Lang
Manifest-Version = 1.0
Bnd-LastModified = 1297248243231
X-Compile-Target-JDK = 1.1
Originally-Created-By = 1.3.1_09-85 ("Apple Computer, Inc.")
Ant-Version = Apache Ant 1.6.5
Package = org.apache.commons.lang
X-Compile-Source-JDK = 1.3
Extension-Name = commons-lang
Implementation-Vendor = Apache Software Foundation

Bundle-Name = commons-lang
Bundle-SymbolicName = commons-lang
Bundle-Version = 2.3
Bundle-ManifestVersion = 2

Import-Package =
        org.apache.commons.lang;resolution:=optional,
        org.apache.commons.lang.builder;resolution:=optional,
        org.apache.commons.lang.enum;resolution:=optional,
        org.apache.commons.lang.enums;resolution:=optional,
        org.apache.commons.lang.exception;resolution:=optional,
        org.apache.commons.lang.math;resolution:=optional,
        org.apache.commons.lang.mutable;resolution:=optional,
        org.apache.commons.lang.text;resolution:=optional,
        org.apache.commons.lang.time;resolution:=optional
Export-Package =
        org.apache.commons.lang;uses:="org.apache.commons.lang.builder,org.apache.commons.lang.math,org.apache.commons.lang.exception",
        org.apache.commons.lang.builder;uses:="org.apache.commons.lang.math,org.apache.commons.lang",
        org.apache.commons.lang.enum;uses:=org.apache.commons.lang,
        org.apache.commons.lang.enums;uses:=org.apache.commons.lang,
        org.apache.commons.lang.exception;uses:=org.apache.commons.lang,
        org.apache.commons.lang.math;uses:=org.apache.commons.lang,
        org.apache.commons.lang.mutable;uses:="org.apache.commons.lang,org.apache.commons.lang.math",
        org.apache.commons.lang.text;uses:=org.apache.commons.lang,
        org.apache.commons.lang.time;uses:=org.apache.commons.lang


Provisioning

Karaf provides a simple, yet flexible, way to provision applications or "features". Such a mechanism is mainly provided by a set of commands available in the features shell. The provisioning system uses xml "repositories" that define a set of features.

Repositories

The complete xml schema for feature descriptor are available on Features XML Schema page. We recommend using this XML schema. It will allow Karaf to validate your repository before parsing. You may also verify your descriptor before adding it to Karaf by simply validation, even from IDE level.

Here is an example of such a repository:

<features xmlns="http://karaf.apache.org/xmlns/features/v1.0.0">
    <feature name="spring" version="3.0.4.RELEASE">
        <bundle>mvn:org.apache.servicemix.bundles/org.apache.servicemix.bundles.aopalliance/1.0_1</bundle>
        <bundle>mvn:org.springframework/spring-core/3.0.4.RELEASE</bundle>
        <bundle>mvn:org.springframework/spring-beans/3.0.4.RELEASE</bundle>
        <bundle>mvn:org.springframework/spring-aop/3.0.4.RELEASE</bundle>
        <bundle>mvn:org.springframework/spring-context/3.0.4.RELEASE</bundle>
        <bundle>mvn:org.springframework/spring-context-support/3.0.4.RELEASE</bundle>
    </feature>
</features>

A repository includes a list of feature elements, each one representing an application that can be installed. The feature is identified by its name which must be unique amongst all the repositories used and consists of a set of bundles that need to be installed along with some optional dependencies on other features and some optional configurations for the Configuration Admin OSGi service.

References to features define in other repositories are allow and can be achieved by adding a list of repository.

<features xmlns="http://karaf.apache.org/xmlns/features/v1.0.0">
  <repository>mvn:org.apache.servicemix.nmr/apache-servicemix-nmr/1.3.0/xml/features</repository>
  <repository>mvn:org.apache.camel.karaf/apache-camel/2.5.0/xml/features</repository>
  <repository>mvn:org.apache.karaf/apache-karaf/2.1.2/xml/features</repository>
  ...

Be careful when you define them as there is a risk of 'cycling' dependencies.

Remark: By default, all the features defined in a repository are not installed at the launch of Apache Karaf (see section hereafter 'h2. Service configuration' for more info).

Bundles

The main information provided by a feature is the set of OSGi bundles that defines the application. Such bundles are URLs pointing to the actual bundle jars. For example, one would write the following definition:

<bundle>http://repo1.maven.org/maven2/org/apache/servicemix/nmr/org.apache.servicemix.nmr.api/1.0.0-m2/org.apache.servicemix.nmr.api-1.0.0-m2.jar</bundle>

Doing this will make sure the above bundle is installed while installing the feature.

However, Karaf provides several URL handlers, in addition to the usual ones (file, http, etc...). One of these is the Maven URL handler, which allow reusing Maven repositories to point to the bundles.

Maven URL Handler

The equivalent of the above bundle would be:

<bundle>mvn:org.apache.servicemix.nmr/org.apache.servicemix.nmr.api/1.0.0-m2</bundle>

In addition to being less verbose, the Maven url handlers can also resolve snapshots and can use a local copy of the jar if one is available in your Maven local repository.

The org.ops4j.pax.url.mvn bundle resolves mvn URLs. This flexible tool can be configured through the configuration service. For example, to find the current repositories type:

karaf@root:/> config:list
...
----------------------------------------------------------------
Pid:            org.ops4j.pax.url.mvn
BundleLocation: mvn:org.ops4j.pax.url/pax-url-mvn/0.3.3
Properties:
   service.pid = org.ops4j.pax.url.mvn
   org.ops4j.pax.url.mvn.defaultRepositories = file:/opt/development/karaf/assembly/target/apache-felix-karaf-1.2.0-SNAPSHOT/system@snapshots
   org.ops4j.pax.url.mvn.repositories = http://repo1.maven.org/maven2, 
                                         http://svn.apache.org/repos/asf/servicemix/m2-repo 
   below = list of repositories and even before the local repository

The repositories checked are controlled by these configuration properties.

For example, org.ops4j.pax.url.mvn.repositories is a comma separate list of repository URLs specifying those remote repositories to be checked. So, to replace the defaults with a new repository at http://www.example.org/repo on the local machine:

karaf@root:/> config:edit org.ops4j.pax.url.mvn
karaf@root:/> config:proplist                  
   service.pid = org.ops4j.pax.url.mvn
   org.ops4j.pax.url.mvn.defaultRepositories = file:/opt/development/karaf/assembly/target/apache-felix-karaf-1.2.0-SNAPSHOT/system@snapshots
   org.ops4j.pax.url.mvn.repositories = http://repo1.maven.org/maven2,
                                        http://svn.apache.org/repos/asf/servicemix/m2-repo
   below = list of repositories and even before the local repository
karaf@root:/> config:propset org.ops4j.pax.url.mvn.repositories http://www.example.org/repo
karaf@root:/> config:update

By default, snapshots are disabled. To enable an URL for snapshots append @snapshots. For example

http://www.example.org/repo@snapshots

Repositories on the local machine are supported through file:/ URLs

Bundle start-level

Available since Karaf 2.0

By default, the bundles deployed through the feature mechanism will have a start-level equals to the value defined in the configuration file config.properties
with the variable karaf.startlevel.bundle=80. This value can be changed using the xml attribute start-level.

  <feature name='my-project' version='1.0.0'>
    <feature version='2.4.0'>camel-spring</feature>
    <bundle start-level='80'>mvn:com.mycompany.myproject/myproject-dao</bundle>    
    <bundle start-level='85'>mvn:com.mycompany.myproject/myproject-service</bundle>
    <bundle start-level='85'>mvn:com.mycompany.myproject/myproject-camel-routing</bundle>
  </feature> 

The advantage in defining the bundle start-level is that you can deploy all your bundles including any required 'infrastructure' bundles (e.g Camel, ActiveMQ)
at the same time and you will have the guarantee when using Spring Dynamic Modules or Blueprint that the Spring context will not be
created without all the required services installed.

Bundle 'stop/start'

The OSGI specification allows for installing a bundle without starting it. To use this functionality, simply add the following attribute in your <bundle> definition

  <feature name='my-project' version='1.0.0'>
    <feature version='2.4.0'>camel-spring</feature>
    <bundle start-level='80' start='false'>mvn:com.mycompany.myproject/myproject-dao</bundle>    
    <bundle start-level='85' start='false'>mvn:com.mycompany.myproject/myproject-service</bundle>
    <bundle start-level='85' start='false'>mvn:com.mycompany.myproject/myproject-camel-routing</bundle>
  </feature> 

Bundle 'dependency'

A bundle can be flagged as being a dependency. Such information can be used by resolvers to compute the full list of bundles to be installed.

Dependent features

Dependent features are useful when a given feature depends on another feature to be installed. Such a dependency can be expressed easily in the feature definition:

<feature name="jbi">
  <feature>nmr</feature>
  ...
</feature>

The effect of such a dependency is to automatically install the required nmr feature when the jbi feature is installed.

A version range can be specified on the feature dependency:

<feature name="spring-dm">
  <feature version="[2.5.6,4)">spring</feature>
  ...
</feature>

In such a case, if no matching feature is already installed, the feature with the highest version available in the range will be installed. If a single version is specified, this version will be chosen. If nothing is specified, the highest available will be installed.

Configurations

The configuration section allows for declaring deployment configuration of the OSGi Configuration Admin service along a set of bundles.
Here is an example of such a configuration:

<config name="com.foo.bar">
  myProperty = myValue
</config>

The name attribute of the configuration element will be used as the ManagedService PID for the configuration set in the Configuration Admin service. When using a ManagedServiceFactory, the name attribute is servicePid-_aliasId_, where servicePid is the PID of the ManagedServiceFactory and aliasId is a label used to uniquely identify a particular service (an alias to the factory generated service PID).

Deploying such a configuration has the same effect as dropping a file named com.foo.bar.cfg into the etc folder.

The content of the configuration element is set of properties parsed using the standard java property mechanism.

Such configuration as usually used with Spring-DM or Blueprint support for the Configuration Admin service, as in the following example, but using plain OSGi APIs will of course work the same way:

<bean ...>
    <property name="propertyName" value="${myProperty}" />
</bean>

<osgix:cm-properties id="cmProps" persistent-id="com.foo.bar">
    <prop key="myProperty">myValue</prop>
</osgix:cm-properties>
<ctx:property-placeholder properties-ref="cmProps" />

There may also be cases where you want to make the properties from multiple configuration files available to your bundle context. This is something you may
want to do if you have a multi-bundle application where there are application properties used by multiple bundles, and each bundle has its own specific
properties. In that case, <ctx:property-placeholder> won't work as it was designed to make only one configuration file available to a bundle context.
To make more than one configuration file available to your bundle-context you would do something like this:

<beans:bean id="myBundleConfigurer"
            class="org.springframework.beans.factory.config.PropertyPlaceholderConfig">
    <beans:property name="ignoreUnresolvablePlaceholders" value="true"/>
    <beans:property name="propertiesArray">
        <osgix:cm-properties id="myAppProps" persistent-id="myApp.props"/>
        <osgix:cm-properties id="myBundleProps" persistent-id="my.bundle.props"/>
    </beans:property>
</beans:bean>

In this example, we are using SpringDM with osgi as the primary namespace. Instead of using ctx:context-placeholder we are using the "PropertyPlaceholderConfig"
class. Then we are passing in a beans array and inside of that array is where we set our osgix:cm-properties elements. This element "returns" a properties bean.

For more information about using the Configuration Admin service in Spring-DM, see the Spring-DM documentation.

Configuration files

In certain cases it is needed not only to provide configurations for the configuration admin service but to add additional
configuration files e.g. a configuration file for jetty (jetty.xml). It even might be helpful to deploy a configuration
file instead of a configuration for the config admin service since. To achieve this the attribute finalname shows the
final destination of the configfile, while the value references the Maven artifact to deploy.

<configfile finalname="/etc/jetty.xml">mvn:org.apache.karaf/apache-karaf/2.2.8/xml/jettyconfig</configfile>

Feature resolver

The resolver attribute on a feature can be set to force the use of a given resolver instead of the default resolution process. A resolver will be use to obtain the list of bundles to actually install for a given feature.
The default resolver will simply return the list of bundles provided in the feature description.
The OBR resolver can be installed and used instead of the standard one. In that case, the resolver will use the OBR service
to determine the list of bundles to install (bundles flagged as dependency will only be used as possible candidates to solve
various constraints).

Commands

Repository management

The following commands can be used to manage the list of descriptors known by Karaf. They use URLs pointing to features descriptors. These URLs can use any protocol known to the Apache Karaf, the most common ones being http, file and mvn.

features:addUrl      Add a list of repository URLs to the features service
features:removeUrl   Remove a list of repository URLs from the features service
features:listUrl     Display the repository URLs currently associated with the features service.
features:refreshUrl  Reload the repositories to obtain a fresh list of features

Karaf maintains a persistent list of these repositories so that if you add one URL and restart Karaf, the features will still be available.

The refreshUrl command is mostly used when developing features descriptors: when changing the descriptor, it can be
handy to reload it in the Kernel without having to restart it or to remove then add the URL again.

Features management

features:install
features:uninstall
features:list

Examples

1. Install features using mvn handler

features:addUrl mvn:org.apache.servicemix.nmr/apache-servicemix-nmr/1.0.0-m2/xml/features
features:install nmr

2. Use file handler to deploy features file

features:addUrl file:base/features/features.xml

Note: The path is relative to the Apache Karaf installation directory

3. Deploy bundles from file system without using Maven

As we can use file:// as protocol handler to deploy bundles, you can use the following syntax to deploy bundles when they are
located in a directory which is not available using Maven

<features xmlns="http://karaf.apache.org/xmlns/features/v1.0.0">
   <feature name="spring-web" version="2.5.6.SEC01">
      <bundle>file:base/bundles/spring-web-2.5.6.SEC01.jar</bundle>
   </feature>
</features>

Note: The path is relative to the Apache Karaf installation directory

Service configuration

A simple configuration file located in [FELIX:karaf]/etc/org.apache.karaf.features.cfg can be modified to customize the behavior when starting the Kernel for the first time.
This configuration file contains two properties:

This configuration file is of interest if you plan to distribute a customized Karaf distribution having pre-installed features. Such a process is detailed in the 6.2. Building custom distributions section.

XML Schema for provisioning

The following schema can be found in Karaf sources. It is also available publicly at url http://karaf.apache.org/xmlns/features/v1.0.0.

Karaf Archives (KAR)

Karaf provides a specific archive format named the KAR (Karaf ARchive).

Basically, the kar format is a jar (so a zip file) which contains a set of feature descriptor and bundle jar files.

For instance, a kar looks like:

all packaged in zip format.

Create a kar archive

You can create a kar file by hand, just by zip compressing a directory representing the kar content.

You can also use the Karaf features maven plugin. The features maven plugin provides an create-kar goal.

The kar-archive goal:
1. Reads all features specified in the features descriptor.
2. For each feature, it resolves the bundles defined in the feature.
3. All bundles are packaged into the kar archive.

For instance, you can use the following POM to create a kar:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>my.groupId</groupId>
    <artifactId>my-kar</artifactId>
    <version>1.0</version>
    <packaging>pom</packaging>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.karaf.tooling</groupId>
                <artifactId>features-maven-plugin</artifactId>
                <version>2.2.4</version>
                <executions>
                    <execution>
                        <id>create-kar</id>
                        <goals>
                            <goal>create-kar</goal>
                        </goals>
                        <configuration>
                            <featuresFile>src/main/resources/features.xml</featuresFile>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

For the example, the features descriptor is very simple:

<?xml version="1.0" encoding="UTF-8"?>
<features>

   <feature name="my" version="1.0">
      <bundle>mvn:commons-collections/commons-collections/3.2.1</bundle>
   </feature>

</features>

To create the kar archive, simply type:

mvn install

and you will have your kar in the target directory.

Deploy a kar archive

Karaf provides a KAR deployer:

karaf@root> la|grep -i archive
[  12] [Active     ] [Created     ] [   30] Apache Karaf :: Deployer :: Karaf Archive (.kar) (2.2.4)

It's a core deployer (you don't need to install additional features).

To deploy a kar, simply drop the kar into the deploy directory. The KAR Deployer will deploy all the kar content starting
from the features descriptor.

The KAR Deployer creates a repository dedicated to your kar (in the $/local-repo) and register the features
descriptor. You can now see your feature available for installation:

karaf@root> features:list|grep -i my
[uninstalled] [1.0             ] my                            repo-0

Now you can use any commands available on features:

karaf@root> features:install my

Configuration

The files in the etc directory are used to set the startup configuration.

For dynamic configuration, Karaf provides a suite of command to administer the configuration service grouped under config. To learn about all currently supported configuration commands type:

Command Description
cancel Change the changes to the configuration being edited.
edit Create or edit a configuration.
list List existing configurations.
propdel Delete a property from the edited configuration.
proplist List properties from the edited configuration.
propset Set a property on the edited configuration.
update Save and propagate changes from the configuration being edited.

Editing

Select Configuration To Edit

For example to edit configuration foo.bar:

karaf@root> config:edit foo.bar

Modify Properties

Use:

* config:proplist to list existing properties
* config:propdel to delete existing properties
* config:propset to set a new value for a property

Any number of properties can be modified within a single editing session.

Commit Or Rollback Changes

Use

* config:update to commit all changes made in the current session
* config:cancel to roll back any changes made in the current session

Pax Web (OSGi HttpService)

The Karaf http feature enables the Pax Web implementation of the OSGi HTTP service.

Installing the HTTP feature

root@karaf> features:install http

Create a file etc/org.ops4j.pax.web.cfg with the following content:

org.osgi.service.http.port=8080

This tells Pax Web to listen to the port 8080. As soon as the http feature is installed and the config
file is present, the following URL will be reachable:

http://localhost:8080/

Registering a servlet with the HttpService manually

See Apache Felix HTTP Service.

Using the Pax Web whiteboard extender

The Pax Web whiteboard extender is part of the war feature. So use the following command to install:

root@karaf> features:install war

The Pax Web whiteboard extender listens to services
of interface type HttpServlet and Filter.
It will register each of these interfaces with the HttpService and remove them as soon as the service goes down.
So it is much more convenient than registering with the HttpService directly.

<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0">
    <service interface="javax.servlet.http.HttpServlet">
        <service-properties>
            <entry key="alias" value="/myservlet"/>
        </service-properties>
        <bean id="myServlet" class="com.example.MyServlet"/>
    </service>
</blueprint>

The above snippet publishes the Servlet MyServlet on http://localhost:8080/myServlet.

Please keep in mind that the Whiteboard pattern for Servlets is not standardized and only works with Pax Web.

Web applications

Installing war support

The following steps will install the "war" feature (support for deploying WAR files with Servlet and JSPs into a Jetty server) into your Karaf instance.

  1. List the available features -
    karaf@root> features:list 
     State        Name
    . . .
    [uninstalled] [2.2.0] obr        karaf-2.2.0
    [uninstalled] [2.2.0] config     karaf-2.2.0
    [uninstalled] [2.2.0] http       karaf-2.2.0
    [uninstalled] [2.2.0] war        karaf-2.2.0
    [uninstalled] [2.2.0] webconsole karaf-2.2.0
    [installed  ] [2.2.0] ssh        karaf-2.2.0
    . . .
    
  2. Install the war feature (and the sub-features it requires) -
    karaf@root> features:install war 
    

    Note: you can use the -v or --verbose to see exactly what Karaf does

    karaf@root> features:install -v war
    Installing feature war 2.1.99-SNAPSHOT
    Installing feature http 2.1.99-SNAPSHOT
    Installing feature jetty 7.1.6.v20100715
    Installing bundle mvn:org.apache.geronimo.specs/geronimo-servlet_2.5_spec/1.1.2
    Found installed bundle: org.apache.servicemix.bundles.asm [10]
    Installing bundle mvn:org.eclipse.jetty/jetty-util/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-io/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-http/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-continuation/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-server/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-security/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-servlet/7.1.6.v20100715
    Installing bundle mvn:org.eclipse.jetty/jetty-xml/7.1.6.v20100715
    Checking configuration file mvn:org.apache.karaf/apache-karaf/2.1.99-SNAPSHOT/xml/jettyconfig
    Installing bundle mvn:org.ops4j.pax.web/pax-web-api/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-spi/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-runtime/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-jetty/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-jsp/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-extender-war/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-extender-whiteboard/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.web/pax-web-deployer/0.8.2-SNAPSHOT
    Installing bundle mvn:org.ops4j.pax.url/pax-url-war/1.2.4
    
  3. Verify the features were installed
    servicemix> features/list
     State        Name
    . . .
    [installed ] [2.2.0] http karaf-2.2.0
    [installed ] [2.2.0] war  karaf-2.2.0
    . . .
    
  4. Verify the installed bundles were started
    karaf@root> osgi:list 
    START LEVEL 100
       ID   State         Level  Name
    . . .
    [ 32] [Active ] [ ] [ 60] geronimo-servlet_2.5_spec (1.1.2) 
    [ 33] [Active ] [ ] [ 60] Apache ServiceMix :: Bundles :: jetty (6.1.22.2) 
    [ 34] [Active ] [ ] [ 60] OPS4J Pax Web - API (1.0.0)
    [ 35] [Active ] [ ] [ 60] OPS4J Pax Web - Service SPI (1.0.0)
    [ 36] [Active ] [ ] [ 60] OPS4J Pax Web - Runtime (1.0.0)
    [ 37] [Active ] [ ] [ 60] OPS4J Pax Web - Jetty (1.0.0)
    [ 38] [Active ] [ ] [ 60] OPS4J Pax Web - Jsp Support (1.0.0)
    [ 39] [Active ] [ ] [ 60] OPS4J Pax Web - Extender - WAR (1.0.0)
    [ 40] [Active ] [ ] [ 60] OPS4J Pax Web - Extender - Whiteboard (1.0.0)
    [ 42] [Active ] [ ] [ 60] OPS4J Pax Web - FileInstall Deployer (1.0.0)
    [ 41] [Active ] [ ] [ 60] OPS4J Pax Url - war:, war-i: (1.2.4)
    . . .
    
  5. The Jetty server should now be listening on http://localhost:8181/, but with no published applications available.
    HTTP ERROR: 404
    NOT_FOUND
    RequestURI=/
    Powered by jetty://
    

Deploying a WAR to the installed web feature

The following steps will describe how to install a simple WAR file (with JSPs or Servlets) to the just installed web feature.

  1. To deploy a WAR (JSP or Servlet) to Jetty, update its MANIFEST.MF to include the required OSGi headers as described here -

    http://team.ops4j.org/wiki/display/ops4j/Pax+Web+Extender+-+War+-+OSGi-fy

  2. Copy the updated WAR (archive or extracted files) to the deploy directory.

If you want to deploy a sample web application into Karaf, you could use the following command:

karaf@root> osgi:install -s webbundle:http://tomcat.apache.org/tomcat-5.5-doc/appdev/sample/sample.war?Bundle-SymbolicName=tomcat-sample&Webapp-Context=/sample

Then open your web browser and point to http://localhost:8181/sample/index.html.

JRE and system packages tuning

Some packages are part of the JRE, but could be provided by tier libraries.

Some examples of package in this case are:

We should define in the Karaf instance which packages should be provided by the JRE or by tier bundles.

Moreover, we should manage the exported packages of JRE depending of the JRE version: the JRE 1.6 provides more packages
than the 1.5 one.

To customize this in Karaf, you can tune the etc/jre.properties file.

In the etc/jre.properties file, you have two properties jre-1.5 and jre-1.6.

They allow you to define the packages exported by the JRE (in function of the runtime version).
Each property provide the exhaustive list of packages provided by the JRE (and so part of the sytem packages).

For instance, a "standard" Karaf distribution provides the following etc/jre.properties:

#
# Java platform package export properties.
#

# Standard package set.  Note that:
#   - javax.transaction* is exported with a mandatory attribute
jre-1.5= \
 javax.accessibility, \
 javax.activity, \
 javax.crypto, \
 javax.crypto.interfaces, \
 javax.crypto.spec, \
 javax.imageio, \
 javax.imageio.event, \
 javax.imageio.metadata, \
 javax.imageio.plugins.bmp, \
 javax.imageio.plugins.jpeg, \
 javax.imageio.spi, \
 javax.imageio.stream, \
 javax.management, \
 javax.management.loading, \
 javax.management.modelmbean, \
 javax.management.monitor, \
 javax.management.openmbean, \
 javax.management.relation, \
 javax.management.remote, \
 javax.management.remote.rmi, \
 javax.management.timer, \
 javax.naming, \
 javax.naming.directory, \
 javax.naming.event, \
 javax.naming.ldap, \
 javax.naming.spi, \
 javax.net, \
 javax.net.ssl, \
 javax.print, \
 javax.print.attribute, \
 javax.print.attribute.standard, \
 javax.print.event, \
 javax.rmi, \
 javax.rmi.CORBA, \
 javax.rmi.ssl, \
 javax.security.auth, \
 javax.security.auth.callback, \
 javax.security.auth.kerberos, \
 javax.security.auth.login, \
 javax.security.auth.spi, \
 javax.security.auth.x500, \
 javax.security.cert, \
 javax.security.sasl, \
 javax.sound.midi, \
 javax.sound.midi.spi, \
 javax.sound.sampled, \
 javax.sound.sampled.spi, \
 javax.sql, \
 javax.sql.rowset, \
 javax.sql.rowset.serial, \
 javax.sql.rowset.spi, \
 javax.swing, \
 javax.swing.border, \
 javax.swing.colorchooser, \
 javax.swing.event, \
 javax.swing.filechooser, \
 javax.swing.plaf, \
 javax.swing.plaf.basic, \
 javax.swing.plaf.metal, \
 javax.swing.plaf.multi, \
 javax.swing.plaf.synth, \
 javax.swing.table, \
 javax.swing.text, \
 javax.swing.text.html, \
 javax.swing.text.html.parser, \
 javax.swing.text.rtf, \
 javax.swing.tree, \
 javax.swing.undo, \
 javax.transaction; javax.transaction.xa; partial=true; mandatory:=partial, \
 javax.xml, \
 javax.xml.datatype, \
 javax.xml.namespace, \
 javax.xml.parsers, \
 javax.xml.transform, \
 javax.xml.transform.dom, \
 javax.xml.transform.sax, \
 javax.xml.transform.stream, \
 javax.xml.validation, \
 javax.xml.xpath, \
 org.ietf.jgss, \
 org.omg.CORBA, \
 org.omg.CORBA_2_3, \
 org.omg.CORBA_2_3.portable, \
 org.omg.CORBA.DynAnyPackage, \
 org.omg.CORBA.ORBPackage, \
 org.omg.CORBA.portable, \
 org.omg.CORBA.TypeCodePackage, \
 org.omg.CosNaming, \
 org.omg.CosNaming.NamingContextExtPackage, \
 org.omg.CosNaming.NamingContextPackage, \
 org.omg.Dynamic, \
 org.omg.DynamicAny, \
 org.omg.DynamicAny.DynAnyFactoryPackage, \
 org.omg.DynamicAny.DynAnyPackage, \
 org.omg.IOP, \
 org.omg.IOP.CodecFactoryPackage, \
 org.omg.IOP.CodecPackage, \
 org.omg.Messaging, \
 org.omg.PortableInterceptor, \
 org.omg.PortableInterceptor.ORBInitInfoPackage, \
 org.omg.PortableServer, \
 org.omg.PortableServer.CurrentPackage, \
 org.omg.PortableServer.POAManagerPackage, \
 org.omg.PortableServer.POAPackage, \
 org.omg.PortableServer.portable, \
 org.omg.PortableServer.ServantLocatorPackage, \
 org.omg.SendingContext, \
 org.omg.stub.java.rmi, \
 org.omg.stub.javax.management.remote.rmi, \
 org.w3c.dom, \
 org.w3c.dom.bootstrap, \
 org.w3c.dom.css, \
 org.w3c.dom.events, \
 org.w3c.dom.html, \
 org.w3c.dom.ls, \
 org.w3c.dom.ranges, \
 org.w3c.dom.stylesheets, \
 org.w3c.dom.traversal, \
 org.w3c.dom.views, \
 org.xml.sax, \
 org.xml.sax.ext, \
 org.xml.sax.helpers

# Standard package set.  Note that:
#   - javax.transaction* is exported with a mandatory attribute
jre-1.6= \
 javax.accessibility, \
 javax.activation, \
 javax.activity, \
 javax.annotation, \
 javax.annotation.processing, \
 javax.crypto, \
 javax.crypto.interfaces, \
 javax.crypto.spec, \
 javax.imageio, \
 javax.imageio.event, \
 javax.imageio.metadata, \
 javax.imageio.plugins.bmp, \
 javax.imageio.plugins.jpeg, \
 javax.imageio.spi, \
 javax.imageio.stream, \
 javax.jws, \
 javax.jws.soap, \
 javax.lang.model, \
 javax.lang.model.element, \
 javax.lang.model.type, \
 javax.lang.model.util, \
 javax.management, \
 javax.management.loading, \
 javax.management.modelmbean, \
 javax.management.monitor, \
 javax.management.openmbean, \
 javax.management.relation, \
 javax.management.remote, \
 javax.management.remote.rmi, \
 javax.management.timer, \
 javax.naming, \
 javax.naming.directory, \
 javax.naming.event, \
 javax.naming.ldap, \
 javax.naming.spi, \
 javax.net, \
 javax.net.ssl, \
 javax.print, \
 javax.print.attribute, \
 javax.print.attribute.standard, \
 javax.print.event, \
 javax.rmi, \
 javax.rmi.CORBA, \
 javax.rmi.ssl, \
 javax.script, \
 javax.security.auth, \
 javax.security.auth.callback, \
 javax.security.auth.kerberos, \
 javax.security.auth.login, \
 javax.security.auth.spi, \
 javax.security.auth.x500, \
 javax.security.cert, \
 javax.security.sasl, \
 javax.sound.midi, \
 javax.sound.midi.spi, \
 javax.sound.sampled, \
 javax.sound.sampled.spi, \
 javax.sql, \
 javax.sql.rowset, \
 javax.sql.rowset.serial, \
 javax.sql.rowset.spi, \
 javax.swing, \
 javax.swing.border, \
 javax.swing.colorchooser, \
 javax.swing.event, \
 javax.swing.filechooser, \
 javax.swing.plaf, \
 javax.swing.plaf.basic, \
 javax.swing.plaf.metal, \
 javax.swing.plaf.multi, \
 javax.swing.plaf.synth, \
 javax.swing.table, \
 javax.swing.text, \
 javax.swing.text.html, \
 javax.swing.text.html.parser, \
 javax.swing.text.rtf, \
 javax.swing.tree, \
 javax.swing.undo, \
 javax.tools, \
 javax.transaction; javax.transaction.xa; partial=true; mandatory:=partial, \
 javax.xml, \
 javax.xml.bind, \
 javax.xml.bind.annotation, \
 javax.xml.bind.annotation.adapters, \
 javax.xml.bind.attachment, \
 javax.xml.bind.helpers, \
 javax.xml.bind.util, \
 javax.xml.crypto, \
 javax.xml.crypto.dom, \
 javax.xml.crypto.dsig, \
 javax.xml.crypto.dsig.dom, \
 javax.xml.crypto.dsig.keyinfo, \
 javax.xml.crypto.dsig.spec, \
 javax.xml.datatype, \
 javax.xml.namespace, \
 javax.xml.parsers, \
 javax.xml.soap, \
 javax.xml.stream, \
 javax.xml.stream.events, \
 javax.xml.stream.util, \
 javax.xml.transform, \
 javax.xml.transform.dom, \
 javax.xml.transform.sax, \
 javax.xml.transform.stax, \
 javax.xml.transform.stream, \
 javax.xml.validation, \
 javax.xml.ws, \
 javax.xml.ws.handler, \
 javax.xml.ws.handler.soap, \
 javax.xml.ws.http, \
 javax.xml.ws.soap, \
 javax.xml.ws.spi, \
 javax.xml.ws.wsaddressing, \
 javax.xml.xpath, \
 org.ietf.jgss, \
 org.omg.CORBA, \
 org.omg.CORBA_2_3, \
 org.omg.CORBA_2_3.portable, \
 org.omg.CORBA.DynAnyPackage, \
 org.omg.CORBA.ORBPackage, \
 org.omg.CORBA.portable, \
 org.omg.CORBA.TypeCodePackage, \
 org.omg.CosNaming, \
 org.omg.CosNaming.NamingContextExtPackage, \
 org.omg.CosNaming.NamingContextPackage, \
 org.omg.Dynamic, \
 org.omg.DynamicAny, \
 org.omg.DynamicAny.DynAnyFactoryPackage, \
 org.omg.DynamicAny.DynAnyPackage, \
 org.omg.IOP, \
 org.omg.IOP.CodecFactoryPackage, \
 org.omg.IOP.CodecPackage, \
 org.omg.Messaging, \
 org.omg.PortableInterceptor, \
 org.omg.PortableInterceptor.ORBInitInfoPackage, \
 org.omg.PortableServer, \
 org.omg.PortableServer.CurrentPackage, \
 org.omg.PortableServer.POAManagerPackage, \
 org.omg.PortableServer.POAPackage, \
 org.omg.PortableServer.portable, \
 org.omg.PortableServer.ServantLocatorPackage, \
 org.omg.SendingContext, \
 org.omg.stub.java.rmi, \
 org.omg.stub.javax.management.remote.rmi, \
 org.w3c.dom, \
 org.w3c.dom.bootstrap, \
 org.w3c.dom.css, \
 org.w3c.dom.events, \
 org.w3c.dom.html, \
 org.w3c.dom.ls, \
 org.w3c.dom.ranges, \
 org.w3c.dom.stylesheets, \
 org.w3c.dom.traversal, \
 org.w3c.dom.views, \
 org.w3c.dom.xpath, \
 org.xml.sax, \
 org.xml.sax.ext, \
 org.xml.sax.helpers

For instance, if we deploy the Apache Geronimo Specs bundle providing the javax.xml.stream package, we have to comment
the javax.xml.stream package in the the jre-1.6 definition. Indeed, jre-1.5 doesn't provide javax.xml.stream, it's
new in the JRE 1.6:

jre-1.6= \
[...]
# javax.xml.stream, \
# javax.xml.stream.events, \
# javax.xml.stream.util, \
[...]

Monitoring and Administration using JMX

Apache Karaf provides a large set of MBeans that allow you to fully monitore and administrate Karaf using any JMX client
(like jconsole for instance).

You can find more or less the same actions that you can do using the shell commands on the JMX layer.

Apache Karaf provides the following MBeans:

Developers Guide

Archetypes

Karaf provides archetypes to easily create commands, manage [features or repository and create a kar archive.
This section describes each of them and explain How to use it.

Create a command (karaf-command-archetype)

This archetype creates a Maven skeleton project that you will use to develop new Karaf commands.

Command line

Using the command line, we can create our project:

mvn archetype:generate \
  -DarchetypeGroupId=org.apache.karaf.archetypes \
  -DartifactId=karaf-command-archetype \
  -DarchetypeVersion=2.2.8 \
  -DgroupId=com.mycompany \
  -DartifactId=com.mycompany.command \
  -Dversion=1.0-SNAPSHOT \
  -Dpackage=com.mycompany.package

Additional parameters

During the maven creation process, additional questions will be asked on the console :

Next, you can import your project in Eclipse/IntelliJ and developp the karaf command.

Create an OSGi bundle (karaf-bundle-archetype)

This archetype creates a Maven skeleton to create an OSGi bundle, including a bundle Activator (a special callback class for bundle start/stop).

Command line

Using the command line, we can create our project:

mvn archetype:generate \
    -DarchetypeGroupId=org.apache.karaf.archetypes \
    -DarchetypeArtifactId=karaf-bundle-archetype \
    -DarchetypeVersion=2.2.8 \
    -DgroupId=com.mycompany \
    -DartifactId=com.mycompany.bundle \
    -Dversion=1.0-SNAPSHOT \
    -Dpackage=com.mycompany.package

Result of Maven command execution

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] Archetype repository missing. Using the one from [org.apache.karaf.archetypes:karaf-bundle-archetype:3.0.0-SNAPSHOT] found in catalog local
[INFO] Using property: groupId = com.mycompany
[INFO] Using property: artifactId = com.mycompany.bundle
[INFO] Using property: version = 1.0-SNAPSHOT
[INFO] Using property: package = com.mycompany.package
Confirm properties configuration:
groupId: com.mycompany
artifactId: com.mycompany.bundle
version: 1.0-SNAPSHOT
package: com.mycompany.package
 Y: :
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: karaf-bundle-archetype:3.0.0-SNAPSHOT
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.bundle
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: packageInPathFormat, Value: com/mycompany/package
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.bundle
[INFO] project created from Archetype in dir: /home/jbonofre/workspace/karaf/test/com.mycompany.bundle
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7.895s
[INFO] Finished at: Mon Dec 19 11:41:44 CET 2011
[INFO] Final Memory: 8M/111M
[INFO] ------------------------------------------------------------------------

Create an OSGi blueprint bundle (karaf-blueprint-archetype)

This archetype creates a Maven skeleton project to create an OSGi blueprint bundle, including a sample bean exposed as an OSGi service in the blueprint XML descriptor.

Command line

Using the command line, we can create our project:

mvn archetype:generate \
    -DarchetypeGroupId=org.apache.karaf.archetypes \
    -DarchetypeArtifactId=karaf-blueprint-archetype \
    -DarchetypeVersion=2.2.8 \
    -DgroupId=com.mycompany \
    -DartifactId=com.mycompany.blueprint \
    -Dversion=1.0-SNAPSHOT \
    -Dpackage=com.mycompany.blueprint

Result of Maven command execution

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] Archetype repository missing. Using the one from [org.apache.karaf.archetypes:karaf-blueprint-archetype:3.0.0-SNAPSHOT] found in catalog local
[INFO] Using property: groupId = com.mycompany
[INFO] Using property: artifactId = com.mycompany.blueprint
[INFO] Using property: version = 1.0-SNAPSHOT
[INFO] Using property: package = com.mycompany.package
Confirm properties configuration:
groupId: com.mycompany
artifactId: com.mycompany.blueprint
version: 1.0-SNAPSHOT
package: com.mycompany.package
 Y: :
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: karaf-blueprint-archetype:3.0.0-SNAPSHOT
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.blueprint
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: packageInPathFormat, Value: com/mycompany/package
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.blueprint
[INFO] project created from Archetype in dir: /home/jbonofre/workspace/karaf/test/com.mycompany.blueprint
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1:06:36.741s
[INFO] Finished at: Mon Dec 19 13:04:43 CET 2011
[INFO] Final Memory: 7M/111M
[INFO] ------------------------------------------------------------------------

Create a features XML (karaf-feature-archetype)

This archetype creates a Maven skeleton project which create a features XML file, using the dependencies that you define in the POM.

Command line

Using the command line, we can create our project:

mvn archetype:generate \
    -DarchetypeGroupId=org.apache.karaf.archetypes \
    -DarchetypeArtifactId=karaf-feature-archetype \
    -DarchetypeVersion=2.2.8 \
    -DgroupId=my.company \
    -DartifactId=my.company.feature \
    -Dversion=1.0-SNAPSHOT \
    -Dpackage=my.company.package

Result of maven command execution

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] Archetype repository missing. Using the one from [org.apache.karaf.archetypes:karaf-feature-archetype:3.0.0-SNAPSHOT] found in catalog local
[INFO] Using property: groupId = com.mycompany
[INFO] Using property: artifactId = com.mycompany.feature
[INFO] Using property: version = 1.0-SNAPSHOT
[INFO] Using property: package = com.mycompany.package
Confirm properties configuration:
groupId: com.mycompany
artifactId: com.mycompany.feature
version: 1.0-SNAPSHOT
package: com.mycompany.package
 Y: :
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: karaf-feature-archetype:3.0.0-SNAPSHOT
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.feature
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: packageInPathFormat, Value: com/mycompany/package
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.feature
[INFO] project created from Archetype in dir: /home/jbonofre/workspace/karaf/test/com.mycompany.feature
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7.262s
[INFO] Finished at: Mon Dec 19 13:20:00 CET 2011
[INFO] Final Memory: 7M/111M
[INFO] ------------------------------------------------------------------------

Create a KAR file (karaf-kar-archetype)

This archetype creates a Maven skeleton project including a features XML sample, used to generate a KAR file.

Command line

Using the command line, we can create our project:

mvn archetype:generate \
    -DarchetypeGroupId=org.apache.karaf.archetypes \
    -DarchetypeArtifactId=karaf-kar-archetype \
    -DarchetypeVersion=2.2.8 \
    -DgroupId=com.mycompany \
    -DartifactId=com.mycompany.kar \
    -Dversion=1.0-SNAPSHOT \
    -Dpackage=com.mycompany.package

Result of maven command execution

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.1:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Interactive mode
[INFO] Archetype repository missing. Using the one from [org.apache.karaf.archetypes:karaf-kar-archetype:3.0.0-SNAPSHOT] found in catalog local
[INFO] Using property: groupId = com.mycompany
[INFO] Using property: artifactId = com.mycompany.kar
[INFO] Using property: version = 1.0-SNAPSHOT
[INFO] Using property: package = com.mycompany.package
Confirm properties configuration:
groupId: com.mycompany
artifactId: com.mycompany.kar
version: 1.0-SNAPSHOT
package: com.mycompany.package
 Y: :
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: karaf-kar-archetype:3.0.0-SNAPSHOT
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.kar
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: packageInPathFormat, Value: com/mycompany/package
[INFO] Parameter: package, Value: com.mycompany.package
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: groupId, Value: com.mycompany
[INFO] Parameter: artifactId, Value: com.mycompany.kar
[INFO] project created from Archetype in dir: /home/jbonofre/workspace/karaf/test/com.mycompany.kar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7.465s
[INFO] Finished at: Mon Dec 19 13:30:15 CET 2011
[INFO] Final Memory: 8M/157M
[INFO] ------------------------------------------------------------------------

Branding the Console

This chapter will show you how to customize the user interface of the Karaf console, making
changes such as a new welcome message and console prompt. This is what we refer to as "branding" Karaf.

Create your branding bundle

At startup, Karaf is looking for a bundle which exports the org.apache.karaf.branding package containing a branding.properties
file.

So you need to create a very simple bundle containing just a org/apache/karaf/branding/branding.properties file.

The Maven POM of your branding bundle should look like this:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>your.group.id</groupId>
    <artifactId>your.branding.artifact.id</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>bundle</packaging>
    <name>Your Branding Bundle Name</name>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <version>2.2</version>
                <extensions>true</extensions>
                <configuration>
                    <instructions>
                        <Bundle-SymbolicName>manual</bundle-SymbolicName>
                        <Import-Package>*</Import-Package>
                        <Private-Package>!*</Private-Package>
                        <Export-Package>
                            org.apache.karaf.branding
                        </Export-Package>
                        <Spring-Context>*;public-context:=false</Spring-Context>
                    </instructions>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Now, add a src/main/resources/org/apache/karaf/branding/branding.properties similar to:

{

}
welcome = \
\u001B[36m        __ __                  ____      \u001B[0m\r\n\
\u001B[36m       / //_/____ __________ _/ __/      \u001B[0m\r\n\
\u001B[36m      / ,<  / __ `/ ___/ __ `/ /_        \u001B[0m\r\n\
\u001B[36m     / /| |/ /_/ / /  / /_/ / __/        \u001B[0m\r\n\
\u001B[36m    /_/ |_|\\__,_/_/   \\__,_/_/         \u001B[0m\r\n\
\r\n\
\u001B[1m  Apache Karaf\u001B[0m (2.2.8)\r\n\
\r\n\
Hit '\u001B[1m<tab>\u001B[0m' for a list of available commands\r\n\
   and '\u001B[1m[cmd] --help\u001B[0m' for help on a specific command.\r\n\
Hit '\u001B[1m<ctrl-d>\u001B[0m' or '\u001B[1mosgi:shutdown\u001B[0m' to shutdown Karaf.\r\n

prompt = \u001B[1m${USER}@${APPLICATION}\u001B[0m>
{

}

As you can see, the branding.properties contains two properties:

As you can see, both strings support ASCII escaped format. For instance \u001B[1m switches the foreground to bold and \u001B[0m
switches it back to normal.

Some examples of customized prompts:

# Define a user with fancy colors
prompt = \u001B[36mmy-karaf-user\u001B[0m\u001B[1m@\u001B[0m\u001B[34m${APPLICATION}\u001B[0m>
# Static sober prompt
prompt = my-user@my-karaf>

Configuring Karaf to use the branding bundle

In order for Karaf to pick up the branding jar please edit the
$KARAF_HOME/etc/custom.properties file to include the following:

org.osgi.framework.system.packages.extra = \
org.apache.karaf.branding;

Installing the branding bundle

Build your branding bundle:

mvn install

and simply drop the generated jar file into the Karaf lib directory.

Start Karaf and you will see your branded Karaf console.

Extending the console

This chapter will guide you through the steps needed to extend the console and create a new shell.
We will leverage Maven, Blueprint and OSGi, so you will need some knowledge of those products.

You may also find some information about the console at http://felix.apache.org/site/rfc-147-overview.html.

Create the project using maven

We first need to create a project using Maven. Let's leverage Maven archetypes for that.

Command line

Using the command line, we can create our project:

mvn archetype:create \
  -DarchetypeArtifactId=maven-archetype-quickstart \
  -DgroupId=org.apache.karaf.shell.samples \
  -DartifactId=shell-sample-commands \
  -Dversion=1.0-SNAPSHOT

This generate the main pom.xml and some additional packages.

Interactive shell

You can also use the interactive mode for creating the skeleton project:

mvn archetype:generate

Use the following values when prompted:

Choose a number:  (1/2/3/4/5/6/7/.../32/33/34/35/36) 15: : 15
Define value for groupId: : org.apache.karaf.shell.samples
Define value for artifactId: : shell-sample-commands
Define value for version:  1.0-SNAPSHOT: : 
Define value for package: : org.apache.karaf.shell.samples

Manual creation

Alternatively, you can simply create the directory shell-sample-commands and create the pom.xml file inside it:


<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

  <modelVersion>4.0.0</modelVersion>

  <groupId>org.apache.karaf.shell.samples</groupId>
  <artifactId>shell-sample-commands<artifactId>
  <packaging>bundle</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>shell-sample-commmands</name>


  <dependencies>
    <dependency>
      <groupId>org.apache.karaf.shell</groupId>
      <artifactId>org.apache.karaf.shell.console</artifactId>
      <version>2.2.8</version>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.felix</groupId>
        <artifactId>maven-bundle-plugin</artifactId>
        <version>2.3.7</version>
        <configuration>
          <instructions>
            <Import-Package>
              org.apache.felix.service.command,
              org.apache.felix.gogo.commands,
              org.apache.karaf.shell.console,
              *
            </Import-Package>
          </instructions>
        </configuration>
      </plugin>
    </plugins>
  </build>

</project>

Configuring for Java 5

We are using annotations to define commands, so we need to ensure Maven will actually use JDK 1.5 to compile the jar.
Just add the following snippet after the dependencies section.


<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <configuration>
        <target>1.5</target>
        <source>1.5</source>
      </configuration>
    </plugin>
  </plugins>
</build>

Loading the project in your IDE

We can use Maven to generate the needed files for your IDE:

Inside the project, run the following command

mvn eclipse:eclipse

or

mvn idea:idea

The project files for your IDE should now be created. Just open the IDE and load the project.

Creating a basic command class

We can now create the command class HelloShellCommand.java


package org.apache.karaf.shell.samples;

import org.apache.felix.gogo.commands.Command;
import org.apache.karaf.shell.console.OsgiCommandSupport;

@Command(scope = "test", name = "hello", description="Says hello")
public class HelloShellCommand extends OsgiCommandSupport {

    @Override
    protected Object doExecute() throws Exception {
        System.out.println("Executing Hello command");
        return null;
    }
}

Creating the associated blueprint configuration files

The blueprint configuration file will be used to create the command and register it in the OSGi registry, which is the way to make the command available to Karaf console. This blueprint file must be located in the OSGI-INF/blueprint/ directory inside the bundle.

If you don't have the src/main/resources directory yet, create it.

mkdir src/main/resources

Then, re-generate the IDE project files and reload it so that this folder is now recognized as a source folder.

Inside this directory, create the OSGI-INF/blueprint/ directory and put the following file inside (the name of this file has no impact at all):


<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0">

    <command-bundle xmlns="http://karaf.apache.org/xmlns/shell/v1.0.0">
        <command name="test/hello">
            <action class="org.apache.karaf.shell.samples.HelloShellCommand"/>
        </command>
    </command-bundle>

</blueprint>

Compiling the jar

Let's try to build the jar. Remove the test classes and sample classes if you used the artifact, then from the command line, run:

mvn install

The end of the maven output should look like:

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------

Test in Karaf

Launch a Karaf instance and run the following command to install the newly created bundle:

karaf@root> osgi:install -s mvn:org.apache.karaf.shell.samples/shell-sample-commands/1.0-SNAPSHOT

Let's try running the command:

karaf@root> test:hello
Executing Hello command

Command completer

A completer allows you to automatically complete a command argument using <tab>. A completer is simply a bean which is injected to a command.

Of course to be able to complete it, the command should require an argument.

Command argument

We add an argument to the HelloCommand:

package org.apache.karaf.shell.samples;

import org.apache.felix.gogo.commands.Command;
import org.apache.felix.gogo.commands.Argument;
import org.apache.karaf.shell.console.OsgiCommandSupport;

@Command(scope = "test", name = "hello", description="Says hello")
public class HelloShellCommand extends OsgiCommandSupport {

    @Argument(index = 0, name = "arg", description = "The command argument", required = false, multiValued = false)
    String arg = null;

    @Override
    protected Object doExecute() throws Exception {
        System.out.println("Executing Hello command");
        return null;
    }
}

The Blueprint configuration file is the same as previously.

Completer bean

A completer is a bean which implements the Completer interface:

package org.apache.karaf.shell.samples;

import org.apache.karaf.shell.console.completer.StringsCompleter;
import org.apache.karaf.shell.console.Completer;

/**
 * <p>
 * A very simple completer.
 * </p>
 */
public class SimpleCompleter implements Completer {

 /**
  * @param buffer the beginning string typed by the user
  * @param cursor the position of the cursor
  * @param candidates the list of completions proposed to the user
  */
 public int complete(String buffer, int cursor, List candidates) {
    StringsCompleter delegate = new StringsCompleter();
    delegate.getStrings().add("one");
    delegate.getStrings().add("two");
    delegate.getStrings().add("three");
    return delegate.complete(buffer, cursor, candidates);
 }

}

Blueprint configuration file

Using Blueprint, you can "inject" the completer linked to your command. The same completer could be used for several commands and a command can have several completers:

<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0">

    <command-bundle xmlns="http://karaf.apache.org/xmlns/shell/v1.0.0">
        <command name="test/hello">
            <action class="org.apache.karaf.shell.samples.HelloShellCommand"/>
            <completers>
                <ref component-id="simpleCompleter"/>
                <null/>
            </completers>
        </command>
    </command-bundle>

    <bean id="simpleCompleter" class="org.apache.karaf.shell.samples.SimpleCompleter"/>

</blueprint>

Test in Karaf

Launch a Karaf instance and run the following command to install the newly created bundle:

karaf@root> osgi:install -s mvn:org.apache.karaf.shell.samples/shell-sample-commands/1.0-SNAPSHOT

Let's try running the command:

karaf@root> test:hello <tab>
 one    two    three

Custom distributions

As Karaf is an OSGi container, it's heavily used as an application and middleware kernel.

You may wish to construct your own Karaf distribution preconfigured to your requirements.
This custom distribution could contain:

Maven assembly

Basically a Karaf custom distribution involves:
1. Uncompressing a standard Karaf distribution in a given directory.
2. Populating the system repo with your features.
3. Populating the lib directory with your branding or other system bundle jar files.
4. Overriding the configuration files in the etc folder.

These tasks could be performed using scripting, or more easily and portable, using Apache Maven and a set of Maven plugins.

For instance, the Maven POM could look like:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM http://maven.apache.org/xsd/maven-4.0.0.xsd">

  <groupId>my.company</groupId>
  <artifactId>mycustom-karaf</artifactId>
  <version>1.0</version>
  <packaging>pom</packaging>
  <name>My Unix Custom Karaf Distribution</name>

  <properties>
    <karaf.version>2.2.2</karaf.version>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.apache.karaf</groupId>
      <artifactId>apache-karaf</artifactId>
      <version>2.2.8</version>
      <type>tar.gz</type>
    </dependency>
    <dependency>
      <groupId>org.apache.karaf</groupId>
      <artifactId>apache-karaf</artifactId>
      <version>2.2.8</version>
      <type>xml</type>
      <classifier>features</classifier>
    </dependency>
  </dependencies>

  <build>
    <resources>
      <resource>
        <directory>/x1/asf/karaf-2.2.x/target/checkout/manual/src/main/filtered-resources</directory>
        <filtering>true</filtering>
        <includes>
          <include>**/*</include>
        </includes>
      </resource>
    </resources>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-resources-plugin</artifactId>
        <executions>
          <execution>
            <id>filter</id>
            <phase>generate-resources</phase>
            <goals>
              <goal>resources</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.karaf.tooling</groupId>
        <artifactId>features-maven-plugin</artifactId>
        <version>2.2.8</version>
        <executions>
          <execution>
           <id>add-features-to-repo</id>
           <phase>generate-resources</phase>
           <goals>
             <goal>add-features-to-repo</goal>
           </goals>
           <configuration>
              <descriptors>
                <descriptor>mvn:org.apache.karaf/apache-karaf/2.2.8/xml/features</descriptor>
                <descriptor>file:/x1/asf/karaf-2.2.x/target/checkout/manual/target/classes/my-features.xml</descriptor>
              </descriptors>
              <features>
                <feature>my-feature</feature>
              </features>
           </configuration>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <executions>
          <execution>
            <id>copy</id>
            <phase>generate-resources</phase>
            <goals>
              <goal>copy</goal>
            </goals>
            <configuration>
               <!-- Define here the artifacts which should be considered in the assembly -->
               <!-- For instance, the branding jar -->
               <artifactItems>
                 <artifactItem>
                    <groupId>my.groupId</groupId>
                    <artifactId>my.branding.id</artifactId>
                    <version>1.0</version>
                    <outputDirectory>target/dependencies</outputDirectory>
                    <destFileName>mybranding.jar</destFileName>
                 </artifactItem>
               </artifactItems>
            </configuration>
          </execution>
          <execution>
            <!-- Uncompress the standard Karaf distribution -->
            <id>unpack</id>
            <phase>generate-resources</phase>
            <goals>
              <goal>unpack</goal>
            </goals>
            <configuration>
              <artifactItems>
                <artifactItem>
                  <groupId>org.apache.karaf</groupId>
                  <artifactId>apache-karaf</artifactId>
                  <type>tar.gz</type>
                  <outputDirectory>target/dependencies</outputDirectory>
                </artifactItem>
              </artifactItems>
            </configuration>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-assembly-plugin</artifactId>
        <executions>
          <execution>
            <id>bin</id>
            <phase>package</phase>
            <goals>
              <goal>single</goal>
            </goals>
            <configuration>
              <descriptors>
                <descriptor>src/main/descriptors/bin.xml</descriptor>
              </descriptors>
              <appendAssemblyId>false</appendAssemblyId>
              <tarLongFileMode>gnu</tarLongFileMode>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>

</project>

The Maven POM will download the Karaf standard distribution and prepare resources to be processed by the Maven assembly plugin.

Your Maven project structure should look like:

For instance, src/main/filtered-resources could contain:

The src/main/distribution contains all your custom Karaf configuration files and scripts, as, for examples:

Now, we can "assemble" our custom distribution using the Maven assembly plugin. The Maven assembly plugin uses an assembly descriptor, configured in POM above to be src/main/descriptors/bin.xml:

<assembly>

    <id>bin</id>

    <formats>
        <format>tar.gz</format>
    </formats>

    <fileSets>

        <!-- Expanded Karaf Standard Distribution -->
        <fileSet>
            <directory>target/dependencies/apache-karaf-2.2.8</directory>
            <outputDirectory>/</outputDirectory>
            <excludes>
                <exclude>**/demos/**</exclude>
                <exclude>bin/**</exclude>
                <exclude>etc/system.properties</exclude>
                <exclude>etc/users.properties</exclude>
                <exclude>etc/org.apache.karaf.features.cfg</exclude>
                <exclude>etc/org.ops4j.pax.logging.cfg</exclude>
                <exclude>LICENSE</exclude>
                <exclude>NOTICE</exclude>
                <exclude>README</exclude>
                <exclude>RELEASE-NOTES</exclude>
                <exclude>karaf-manual*.html</exclude>
                <exclude>karaf-manual*.pdf</exclude>
            </excludes>
        </fileSet>

        <!-- Copy over bin/* separately to get the correct file mode -->
        <fileSet>
            <directory>target/dependencies/apache-karaf-2.2.8</directory>
            <outputDirectory>/</outputDirectory>
            <includes>
                <include>bin/admin</include>
                <include>bin/karaf</include>
                <include>bin/start</include>
                <include>bin/stop</include>
            </includes>
            <fileMode>0755</fileMode>
        </fileSet>

        <!-- Copy over jar files -->
        <fileSet>
            <directory>target/dependencies</directory>
            <includes>
                <include>my-custom.jar</include>
            </includes>
            <outputDirectory>/lib/</outputDirectory>
        </fileSet>

        <fileSet>
            <directory>src/main/distribution</directory>
            <outputDirectory>/</outputDirectory>
            <fileMode>0644</fileMode>
        </fileSet>
        <fileSet>
            <directory>target/classes/etc</directory>
            <outputDirectory>/etc/</outputDirectory>
            <lineEnding>unix</lineEnding>
            <fileMode>0644</fileMode>
        </fileSet>

        <fileSet>
            <directory>target/features-repo</directory>
            <outputDirectory>/system</outputDirectory>
        </fileSet>

    </fileSets>

    <files>
        <file>
            <source>/x1/asf/karaf-2.2.x/target/checkout/manual/target/dependencies/apache-karaf-2.2.8/bin/karaf</source>
            <outputDirectory>/bin/</outputDirectory>
            <destName>my-custom</destName>
            <fileMode>0755</fileMode>
            <lineEnding>unix</lineEnding>
        </file>
        <file>
            <source>/x1/asf/karaf-2.2.x/target/checkout/manual/target/classes/features.xml</source>
            <outputDirectory>/system/my.groupid/my-features/2.2.8</outputDirectory>
            <destName>my-features-2.2.8-features.xml</destName>
            <fileMode>0644</fileMode>
            <lineEnding>unix</lineEnding>
        </file>
    </files>

</assembly>

To build your custom Karaf distribution, just run:

mvn install

You will find your Karaf custom distribution tar.gz in the target directory.

Roadmap

A distribution goal is in preparation in the next Karaf

Custom distribution examples

Security framework

Karaf supports JAAS with some enhancements to allow JAAS to work nicely in an OSGi environment. This framework also features an OSGi keystore manager with the ability to deploy new keystores or truststores at runtime.

Overview

This feature allows runtime deployment of JAAS based configuration for use in various parts of the application. This includes the remote console login, which uses the karaf realm, but which is configured with a dummy login module by default. These realms can also be used by the NMR, JBI components or the JMX server to authenticate users logging in or sending messages into the bus.

In addition to JAAS realms, you can also deploy keystores and truststores to secure the remote shell console, setting up HTTPS connectors or using certificates for WS-Security.

A very simple XML schema for spring has been defined, allowing the deployment of a new realm or a new keystore very easily.

Schema

To override or deploy a new realm, you can use the following XSD which is supported by a Spring namespace handler and can thus be defined in a Spring xml configuration file.

Following is the XML Schema to use when defining Karaf realms:

You can find the schema at the following location.

Here are two examples using this schema:


<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:jaas="http://karaf.apache.org/xmlns/jaas/v1.0.0"
           xmlns:ext="http://aries.apache.org/blueprint/xmlns/blueprint-ext/v1.0.0">

    <!-- Bean to allow the $[karaf.base] property to be correctly resolved -->
    <ext:property-placeholder placeholder-prefix="$[" placeholder-suffix="]"/>

    <jaas:config name="myrealm">
        <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                     flags="required">
            users = $[karaf.base]/etc/users.properties
        </jaas:module>
    </jaas:config>

    <service interface="org.apache.karaf.jaas.modules.BackingEngineFactory">
        <bean class="org.apache.karaf.jaas.modules.properties.PropertiesBackingEngineFactory"/>
    </service>

</blueprint>

NB: Don't forge to expose the BackingEngine as an OSGi service.


<jaas:keystore xmlns:jaas="http://karaf.apache.org/xmlns/jaas/v1.1.0"
               name="ks"
               rank="1"
               path="classpath:privatestore.jks"
               keystorePassword="keyStorePassword"
               keyPasswords="myalias=myAliasPassword">
</jaas:keystore>

The id attribute is the blueprint id of the bean, but it will be used by default as the name of the realm if no name attribute is specified. Additional attributes on the config elements are a rank, which is an integer. When the LoginContext looks for a realm for authenticating a given user, the realms registered in the OSGi registry are matched against the required name. If more than one realm is found, the one with the highest rank will be used, thus allowing the override of some realms with new values. The last attribute is publish which can be set to false to not publish the realm in the OSGi registry, thereby disabling the use of this realm.

Each realm can contain one or more module definitions. Each module identifies a LoginModule and the className attribute must be set to the class name of the login module to use. Note that this login module must be available from the bundle classloader, so either it has to be defined in the bundle itself, or the needed package needs to be correctly imported. The flags attribute can take one of four values that are explained on the JAAS documentation.
The content of the module element is parsed as a properties file and will be used to further configure the login module.

Deploying such a code will lead to a JaasRealm object in the OSGi registry, which will then be used when using the JAAS login module.

Configuration override and use of the rank attribute

The rank attribute on the config element is tied to the ranking of the underlying OSGi service. When the JAAS framework performs an authentication, it will use the realm name to find a matching JAAS configuration. If multiple configurations are used, the one with the highest rank attribute will be used.
So if you want to override the default security configuration in Karaf (which is used by the ssh shell, web console and JMX layer), you need to deploy a JAAS configuration with the name name="karaf" and rank="1".


<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
           xmlns:jaas="http://karaf.apache.org/xmlns/jaas/v1.1.0"
           xmlns:ext="http://aries.apache.org/blueprint/xmlns/blueprint-ext/v1.0.0">

    <!-- Bean to allow the $[karaf.base] property to be correctly resolved -->
    <ext:property-placeholder placeholder-prefix="$[" placeholder-suffix="]"/>

    <jaas:config name="karaf" rank="1">
        <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule"
                     flags="required">
            users = $[karaf.base]/etc/users.properties
            ...
        </jaas:module>
    </jaas:config>

</blueprint>

Architecture

Due to constraints in the JAAS specification, one class has to be available for all bundles. This class is called ProxyLoginModule and is a LoginModule that acts as a proxy for an OSGi defines LoginModule. If you plan to integrate this feature into another OSGi runtime, this class must be made available from the system classloader and the related package be part of the boot delegation classpath (or be deployed as a fragment attached to the system bundle).

The xml schema defined above allows the use of a simple xml (leveraging spring xml extensibility) to configure and register a JAAS configuration for a given realm. This configuration will be made available into the OSGi registry as a JaasRealm and the OSGi specific Configuration will look for such services. Then the proxy login module will be able to use the information provided by the realm to actually load the class from the bundle containing the real login module.

Available realms

Karaf comes with several login modules to handle authentication needs for your environment.

PropertiesLoginModule

LoginModule org.apache.karaf.jaas.modules.properties.PropertiesLoginModule
BackingEngineFactory org.apache.karaf.jaas.modules.properties.PropertiesBackingEngineFactory

This login module is the one configured by default. It uses a properties text file to load the users, passwords and roles.

Name Description
users location of the properties file

This file uses the properties file format.
The format of the properties is as follows, with each line defining a user, its password and associated roles:

user=password[,role][,role]...

<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                 flags="required">
        users = $[karaf.base]/etc/users.properties
    </jaas:module>
</jaas:config>

OsgiConfigLoginModule

LoginModule org.apache.karaf.jaas.modules.osgi.OsgiConfigLoginModule
BackingEngineFactory

The OsgiConfigLoginModule uses the OSGi ConfigurationAdmin service to provide the users, passwords and roles.

Name Description
pid the PID of the configuration containing user definitions

The format of the configuration is the same than for the PropertiesLoginModule.

JDBCLoginModule

LoginModule org.apache.karaf.jaas.modules.jdbc.JDBCLoginModule
BackingEngineFactory org.apache.karaf.jaas.modules.jdbc.JDBCBackingEngineFactory

The JDBCLoginModule uses a database to load the users, passwords and roles from a provided data source (normal or XA). The data source and the queries for password and role retrieval are configurable using the following parameters.

Name Description
datasource The datasource as on OSGi ldap filter or as JDNI name
query.password The SQL query that retries the password of the user
query.role The SQL query that retries the roles of the user

Passing a data source as an OSGi ldap filter

To use an OSGi ldap filter, the prefix osgi: needs to be provided, as shown below:


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.jdbc.JDBCLoginModule" 
                 flags="required">
        datasource = osgi:javax.sql.DataSource/(osgi.jndi.service.name=jdbc/karafdb)
        query.password = SELECT PASSWORD FROM USERS WHERE USERNAME=?
        query.role = SELECT ROLE FROM ROLES WHERE USERNAME=?
    </jaas:module>
</jaas:config>

Passing a data source as a JNDI name

To use an JNDI name, the prefix jndi: needs to be provided. The example below assumes the use of Aries JNDI to expose services via JNDI.


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.jdbc.JDBCLoginModule" 
                 flags="required">
        datasource = jndi:aries:services/javax.sql.DataSource/(osgi.jndi.service.name=jdbc/karafdb)
        query.password = SELECT PASSWORD FROM USERS WHERE USERNAME=?
        query.role = SELECT ROLE FROM ROLES WHERE USERNAME=?
    </jaas:module>
</jaas:config>

LDAPLoginModule

LoginModule org.apache.karaf.jaas.modules.ldap.LDAPLoginModule
BackingEngineFactory

The LDAPLoginModule uses LDAP to load the users and roles and bind the users on the LDAP to check passwords.

The LDAPLoginModule supports the following parameters:

Name Description
connection.url The LDAP connection URL, e.g. ldap://hostname
connection.username Admin username to connect to the LDAP. This parameter is optional, if it's not provided, the LDAP connection will be anonymous.
connection.password Admin password to connect to the LDAP. Only used if the connection.username is specified.
user.base.dn The LDAP base DN used to looking for user, e.g. ou=user,dc=apache,dc=org
user.filter The LDAP filter used to looking for user, e.g. (uid=%u) where %u will be replaced by the username.
user.search.subtree If "true", the user lookup will be recursive (SUBTREE). If "false", the user lookup will be performed only at the first level (ONELEVEL).
role.base.dn The LDAP base DN used to looking for roles, e.g. ou=role,dc=apache,dc=org
role.filter The LDAP filter used to looking for user's role, e.g. (member:=uid=%u)
role.name.attribute The LDAP role attribute containing the role string used by Karaf, e.g. cn
role.search.subtree If "true", the role lookup will be recursive (SUBTREE). If "false", the role lookup will be performed only at the first level (ONELEVEL).
authentication Define the authentication backend used on the LDAP server. The default is simple.
initial.context.factory Define the initial context factory used to connect to the LDAP server. The default is com.sun.jndi.ldap.LdapCtxFactory
ssl If "true" or if the protocol on the connection.url is ldaps, an SSL connection will be used
ssl.provider The provider name to use for SSL
ssl.protocol The protocol name to use for SSL (SSL for example)
ssl.algorithm The algorithm to use for the KeyManagerFactory and TrustManagerFactory (PKIX for example)
ssl.keystore The key store name to use for SSL. The key store must be deployed using a jaas:keystore configuration.
ssl.keyalias The key alias to use for SSL
ssl.truststore The trust store name to use for SSL. The trust store must be deployed using a jaas:keystore configuration.

A example of LDAPLoginModule usage follows:


<jaas:config name="karaf">
  <jaas:module className="org.apache.karaf.jaas.modules.ldap.LDAPLoginModule" flags="required">
        connection.url = ldap://localhost:389
        user.base.dn = ou=user,dc=apache,dc=org
        user.filter = (cn=%u)
        user.search.subtree = true
        role.base.dn = ou=group,dc=apache,dc=org
        role.filter = (member:=uid=%u)
        role.name.attribute = cn
        role.search.subtree = true
        authentication = simple
  </jaas:module>
</jaas:config>

If you wish to use an SSL connection, the following configuration can be used as an example:


<ext:property-placeholder />

<jaas:config name="karaf" rank="1">
    <jaas:module className="org.apache.karaf.jaas.modules.ldap.LDAPLoginModule" flags="required">
        connection.url = ldaps://localhost:10636
        user.base.dn = ou=users,ou=system
        user.filter = (uid=%u)
        user.search.subtree = true
        role.base.dn = ou=groups,ou=system
        role.filter = (uniqueMember=uid=%u)
        role.name.attribute = cn
        role.search.subtree = true
        authentication = simple
        ssl.protocol=SSL
        ssl.truststore=ks
        ssl.algorithm=PKIX
    </jaas:module>
</jaas:config>

<jaas:keystore name="ks"
               path="file:///${karaf.home}/etc/trusted.ks"
               keystorePassword="secret" />

Encryption service

The EncryptionService is a service registered in the OSGi registry providing means to encrypt and check encrypted passwords. This service acts as a factory for Encryption objects actually performing the encryption.

This service is used in all Karaf login modules to support encrypted passwords.

Configuring properties

Each login module supports the following additional set of properties:

Name Description
encryption.name Name of the encryption service registered in OSGi (cf. paragraph below)
encryption.enabled Boolean used to turn on encryption
encryption.prefix Prefix for encrypted passwords
encryption.suffix Suffix for encrypted passwords
encryption.algorithm Name of an algorithm to be used for hashing, like "MD5" or "SHA-1"
encryption.encoding Encrypted passwords encoding (can be hexadecimal or base64)
role.policy A policy for identifying roles (can be prefix or group) below)
role.discriminator A discriminator value to be used by the role policy

A simple example follows:


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                 flags="required">
        users = $[karaf.base]/etc/users.properties
        encryption.enabled = true
        encryption.algorithm = MD5
        encryption.encoding = hexadecimal
    </jaas:module>
</jaas:config>

Prefix and suffix

The login modules have the ability to support both encrypted and plain passwords at the same time. In some cases, some login modules may be able to encrypt the passwords on the fly and save them back in an encrypted form.

Jasypt

Karaf default installation comes with a simple encryption service which usually fulfills simple needs. However, in some cases, you may need to install the Jasypt library which provides stronger encryption algorithms and more control over them.

To install the Jasypt library, the easiest way is to install the available feature:

karaf@root> features:install jasypt-encryption

It will download and install the required bundles and also register an EncryptionService for Jasypt in the OSGi registry.

When configuring a login module to use Jasypt, you need to specify the encryption.name property and set it to a value of jasypt to make sure the Jasypt encryption service will be used.

In addition to the standard properties above, the Jasypt service provides the following parameters:

Name Description
providerName Name of the java.security.Provider name to use for obtaining the digest algorithm
providerClassName Class name for the security provider to be used for obtaining the digest algorithm
iterations Number of times the hash function will be applied recursively
saltSizeBytes Size of the salt to be used to compute the digest
saltGeneratorClassName Class name of the salt generator

A typical realm definition using Jasypt encryption service would look like:


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                 flags="required">
        users = $[karaf.base]/etc/users.properties
        encryption.enabled = true
        encryption.name = jasypt
        encryption.algorithm = SHA-256
        encryption.encoding = base64
        encryption.iterations = 100000
        encryption.saltSizeBytes = 16
    </jaas:module>
</jaas:config>

Role discovery policies

The JAAS specification does not provide means to distinguish between User and Role Principals without referring to the specification classes. In order to provide means to the application developer to decouple the application from Karaf JAAS implementation role policies have been created.

A role policy is a convention that can be adopted by the application in order to identify Roles, without depending from the implementation. Each role policy can be cofigured by setting a "role.policy" and "role.discriminator" property to the login module configuration. Currently, Karaf provides two policies that can be applied to all Karaf Login Modules.

  1. Prefixed Roles
  2. Grouped Roles

Prefixed Roles
When the prefixed role policy is used the login module applies a configurable prefix (property role.discriminator) to the role, so that the application can identify the role's principals by its prefix. Example:


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                 flags="required">
        users = $[karaf.base]/etc/users.properties
        role.policy = prefix
        role.discriminator = ROLE_
    </jaas:module>
</jaas:config>

The application can identify the role principals using a snippet like this:


LoginContext ctx = new LoginContext("karaf", handler);
ctx.login();
authenticated = true;
subject = ctx.getSubject();
for (Principal p : subject.getPrincipals()) {
   	if (p.getName().startsWith("ROLE_")) {
   	   	roles.add((p.getName().substring("ROLE_".length())));
   	}
}

Grouped Roles
When the group role policy is used the login module provides all roles as members of a group with a configurable name (property role.discriminator). Example:


<jaas:config name="karaf">
    <jaas:module className="org.apache.karaf.jaas.modules.properties.PropertiesLoginModule" 
                 flags="required">
        users = $[karaf.base]/etc/users.properties
        role.policy = group
        role.discriminator = ROLES
    </jaas:module>
</jaas:config>

LoginContext ctx = new LoginContext("karaf", handler);
ctx.login();
authenticated = true;
subject = ctx.getSubject();
for (Principal p : subject.getPrincipals()) {
    if ((p instanceof Group) && ("ROLES".equalsIgnoreCase(p.getName()))) {
        Group g = (Group) p;
        Enumeration<? extends Principal> members = g.members();
        while (members.hasMoreElements()) {
            Principal member = members.nextElement();
            roles.add(member.getName());
        }
    }
}

Default role policies

The previous section describes how to leverage role policies. However, Karaf provides a default role policy, based on the following class names:

It allows you to directly handling the role class:


String rolePrincipalClass = "org.apache.karaf.jaas.modules.RolePrincipal";

for (Principal p : subject.getPrincipals()) {
	if (p.getClass().getName().equals(rolePrincipalClass)) {
		roles.add(p.getName());
	}
}

Using the features-maven-plugin

The features-maven-plugin provides several goals to help you create and validate features XML descriptors as well as leverage your features to create a custom Karaf distribution.

Goal Description
features:add-features-to-repo Copies all the bundles required for a given set of features into a directory
(e.g. for creating your own Karaf-based distribution)
features:generate-features-file Deprecated - use features:generate-features-xml instead
features:generate-features-xml Generates a features XML descriptor for a set of bundles
features:validate Validate a features XML descriptor by checking if all the required imports can be matched to exports
{{features:create-kar

Configure the features-maven-plugin

In order to use the features-maven-plugin, you have to define the plugin in your project's pom.xml file:


<project>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.karaf.tooling</groupId>
        <artifactId>features-maven-plugin</artifactId>
        <version>2.2.8</version>

        <executions>
          <!-- add execution definitions here -->
        </executions>
      </plugin>
    </plugins>
  </build>  
</project>

Goal features:add-features-to-repo

The features:add-features-to-repo goal adds all the required bundles for a given set of features into directory. You can use this goal to create a /system directory for building your own Karaf-based distribution.

By default, the Karaf core features descriptors (standard and enterprise) are automatically included in the descriptors set.

Example

The example below copies the bundles for the spring and war features defined in the Karaf features XML descriptor into the target/features-repo directory.


<project>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.karaf.tooling</groupId>
        <artifactId>features-maven-plugin</artifactId>
        <version>2.2.8</version>

        <executions>
          <execution>
            <id>add-features-to-repo</id>
            <phase>generate-resources</phase>
            <goals>
              <goal>add-features-to-repo</goal>
            </goals>
            <configuration>
              <descriptors>
                <descriptor>mvn:my.groupid/my.artifactid/1.0.0/xml/features</descriptor>
              </descriptors>
              <features>
                <feature>spring</feature>
                <feature>war</feature>
                <feature>my</feature>
                <feature>other/1.0-SNAPSHOT</feature>
              </features>
              <repository>target/features-repo</repository>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>  
</project>

Parameters

Name Type Description
descriptors String[] List of features XML descriptors where the features are defined
NB: Karaf core features descriptors (standard and enterprise) are automatically added in this list
features String[] List of features that bundles should be copied to the repository directory. A feature could be just a feature name or a name/version. If it's just a name, the features-maven-plugin will take the first feature with the given name, whatever the version is.
repository File The directory where the bundles will be copied by the plugin goal
karafVersion String Target Karaf version to use to resolve the Karaf core features descriptors (standard and enterprise)

Goal features:generate

The features:generate goal generates a features XML file for every bundle listed in the project's dependencies. In order to satisfy the required imports in these bundles, the plugin will add bundles:

Afterwards, the generated file will be attached to the build as an additional build artifact (by default as group:artifact:version:xml:features).

Example

The example below generates one feature that installs bundle mvn:org.apache:bundle1:1.0 in a features XML file called target/features.xml. It will find bundle in Apache Karaf 2.2.8, the transitive dependencies for this POM and the bundles listed in src/main/resources/bundles.properties.


<project>
  <dependencies>
    <dependency>
      <groupId>org.apache</groupId>
      <artifactId>bundle1</artifactId>
      <version>1.0</version>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.karaf.tooling</groupId>
        <artifactId>features-maven-plugin</artifactId>
        <version>2.2.8</version>
          <executions>
            <execution>
              <id>generate</id>
              <phase>generate-resources</phase>
              <goals>
                <goal>generate</goal>
              </goals>
              <configuration>
                <bundles>src/main/resources/bundles.properties</bundles>
                <kernelVersion>2.2.8</kernelVersion>
                <outputFile>target/features.xml</outputFile>
              </configuration>
            </execution>
          </executions>
        </plugin>
    </plugins>
  </build>  
</project>

Parameters

Name Type Description
outputFile File Name of the features XML file that is being generated
Default value: /x1/asf/karaf-2.2.x/target/checkout/manual/target/classes/feature.xml
attachmentArtifactType String The artifact type for attaching the generated file to the project
Default value: {{xml})
attachmentArtifactClassifier String The artifact classifier for attaching the generated file to the project
Default value: features
kernelVersion String The version of Karaf that is used to determine system bundles and default provided features
bundles File A properties file that contains a list of bundles that will be used to generate the features.xml file

Goal features:validate

The features:validate goal validates a features XML descriptor by checking if all the required imports for the bundles defined in the features can be matched to a provided export.

By default, the plugin tries to add the Karaf standard features (standard and enterprise) in the repositories set.
It means that it's not necessary to explicitly define the Karaf features descriptor in the repository section of your features descriptor.

Example

The example below validates the features defined in the target/features.xml by checking all the imports and exports. It reads the definition for the packages that are exported by the system bundle from the src/main/resources/config.properties file.


<project>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.karaf.tooling</groupId>
        <artifactId>features-maven-plugin</artifactId>
        <version>2.2.8</version>
          <executions>
            <execution>
              <id>validate</id>
              <phase>process-resources</phase>
              <goals>
                <goal>validate</goal>
              </goals>
              <configuration>
                <file>target/features.xml</file>
                <karafConfig>src/main/resources/config.properties</karafConfig>
              </configuration>
            </execution>
          </executions>
          <dependencies>
            <dependency>
              <groupId>org.slf4j</groupId>
              <artifactId>slf4j-simple</artifactId>
              <version>1.4.3</version>
	        </dependency>
          </dependencies>
        </plugin>
    </plugins>
  </build>  
</project>

Parameters

Name Type Description
file File The features XML descriptor file to validate.
Default value: /x1/asf/karaf-2.2.x/target/checkout/manual/target/classes/features.xml
karafConfig String The Karaf config.properties file to use during the validation process
Default value: config.properties
jreVersion String The JRE version that is used during the validation process
Default value: {{jre-1.5})
karafVersion String The target Karaf version used to get the Karaf core features (standard and enterprise)
Default value is the version of the plugin
repositories String[] Additional features XML descriptors that will be used during the validation process

Troubleshooting, Debugging, Profiling, and Monitoring

Troubleshooting

Logging

Logging is easy to control through the console, with commands grouped under log shell. To learn about the available logging commands type:

karaf@root> log<tab>

log:display              log:display-exception    log:get                  log:set
karaf@root>

Typical usage is:

# Use log:set to dynamically change the global log level
# Execute the problematic operation
# Use log:display (or log:display-exception to display the log

Worst Case Scenario

If you end up with a Karaf in a really bad state (i.e. you can not boot it anymore) or you just want to revert to a clean state quickly, you can safely remove the data directory in the installation directory. This folder contains transient data and will be recreated if removed when you relaunch Karaf.
You may also want to remove the files in the deploy folder to avoid them being automatically installed when Karaf is started the first time.

Debugging

Usually, the easiest way to debug Karaf or any application deployed onto it is to use remote debugging.
Remote debugging can be easily activated by using the debug parameter on the command line.

> bin/karaf debug
{noformat
or on Windows

> bin\karaf.bat debug
{noformat

Another option is to set the KARAF_DEBUG environment variable to TRUE.

This can be done using the following command on Unix systems:

export KARAF_DEBUG=true

On Windows, use the following command

set KARAF_DEBUG=true

Then, you can launch Karaf using the usual way:

bin/karaf

or

bin\karaf.bat

Last, inside your IDE, connect to the remote application (the default port to connect to is 5005).

This option works fine when it is needed to debug a project deployed top of Apache Karaf. Nevertheless, you will be blocked
if you would like to debug the server Karaf. In this case, you can change the following parameter suspend=y in the
karaf.bat script file. That will cause the JVM to pause just before running main() until you attach a debugger then it
will resume the execution. This way you can set your breakpoints anywhere in the code and you should be able to hit them
no matter how early in the startup they are.

export DEFAULT_JAVA_DEBUG_OPTS='-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005'

and on Windows,

set DEFAULT_JAVA_DEBUG_OPTS='-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005'

Profiling

YourKit

You need a few steps to be able to profile Karaf using YourKit.
The first one is to edit the etc/config.properties configuration file and add the following property:

org.osgi.framework.bootdelegation=com.yourkit.*

Then, set the JAVA_OPTS environment variable:

export JAVA_OPTS='-Xmx512M -agentlib:yjpagent'

or, on Windows

set JAVA_OPTS='-Xmx512M -agentlib:yjpagent'

Run Karaf from the console, and you should now be able to connect using YourKit standalone or from your favorite IDE.

Monitoring

Karaf uses JMX for monitoring and management of all Karaf components.

The JMX connection could be:

Using JMX, you can have a clean overview of the running Karaf instance:

You can manage Karaf features like you are in the shell. For example, you have access to the Admin service MBean, allowing you to create, rename, destroy, change SSH port, etc. Karaf instances:

You can also manage Karaf features MBean to list, install, and uninstall Karaf features:

Programmatically connect to the console

A connection to the Karaf console can also be done programmatically.
The following code is a simplified version of the code from the client library.


import org.apache.sshd.ClientChannel;
import org.apache.sshd.ClientSession;
import org.apache.sshd.SshClient;
import org.apache.sshd.client.future.ConnectFuture;

public class Main {

    public static void main(String[] args) throws Exception {
        String host = "localhost";
        int port = 8101;
        String user = "karaf";
        String password = "karaf";

        SshClient client = null;
        try {
            client = SshClient.setUpDefaultClient();
            client.start();
            ConnectFuture future = client.connect(host, port);
            future.await();
            ClientSession session = future.getSession();
            session.authPassword(user, password);
            ClientChannel channel = session.createChannel("shell");
            channel.setIn(System.in);
            channel.setOut(System.out);
            channel.setErr(System.err);
            channel.open();
            channel.waitFor(ClientChannel.CLOSED, 0);
        } catch (Throwable t) {
            t.printStackTrace();
            System.exit(1);
        } finally {
            try {
                client.stop();
            } catch (Throwable t) { }
        }
        System.exit(0);
    }

}

You can find a more complete example at the following location.

Writing integration tests

We recommend using PAX Exam to write integration tests when developing
applications using Karaf.

Karaf provides an helper library to help writing such integration tests.


   @Configuration
   public static Option[] configuration() throws Exception{
       return combine(
           // Default karaf environment
           Helper.getDefaultOptions(),
           // Test on both equinox and felix
           equinox(), felix()
       );
   }

If you need to provision a few features in addition to the default Karaf environment, you can do so by adding the following code:


           scanFeatures(
                  maven().groupId("org.apache.felix.karaf")
                         .artifactId("apache-felix-karaf")
                         .type("xml").classifier("features")
                         .versionAsInProject(),
                  "obr", "wrapper"
           ),

Add extended information to bundles

Karaf supports a OSGI-INF/bundle.info file in a bundle.

This file is extended description of the bundle. It supports ASCII character declarations (for adding color, formatting, etc).

For instance, you can define a bundle like this (using Apache Felix maven-bundle-plugin):

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>my.groupId</groupId>
    <artifactId>my.bundle</artifactId>
    <version>1.0-SNAPSHOT</version>
    <name>My Bundle</name>
    <description>My bundle short description</description>

    <build>
        <resources>
            <resource>
                <directory>/x1/asf/karaf-2.2.x/target/checkout/manual/src/main/resources</directory>
                <filtering>true</filtering>
                <includes>
                    <include>**/*</include>
                </includes>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <version>2.2.0</version>
                <extensions>true</extensions>
                <configuration>
                    <instructions>
                        <Bundle-SymbolicName>manual</Bundle-SymbolicName>
                        ...
                    </instructions>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

And simply add a src/main/resources/OSGI-INF/bundle.info file containing, for instance:

\u001B[1mSYNOPSIS\u001B[0m
    The Apache Software Foundation provides support for the Apache community of open-source software projects.
    The Apache projects are characterized by a collaborative, consensus based development process, an open and
    pragmatic software license, and a desire to create high quality software that leads the way in its field.
    We consider ourselves not simply a group of projects sharing a server, but rather a community of developers
    and users.

\u001B[1mDESCRIPTION\u001B[0m
    Long description of your bundle, including usage, etc.

\u001B[1mSEE ALSO\u001B[0m
    \u001B[36mhttp://yourside\u001B[0m
    \u001B[36mhttp://yourside/docs\u001B[0m

You can display this extended information using:

root@karaf> osgi:info

Creating bundles for third party dependencies

Karaf supports the wrap: protocol execution.

It allows for directly deploying third party dependencies, like Apache Commons Lang:

root@karaf> osgi:install wrap:mvn:commons-lang/commons-lang/2.4

You can specify OSGi statements in the wrap URL:

root@karaf> osgi:install wrap:mvn:commons-lang/commons-lang/2.4,Bundle-SymbolicName=commons-lang&Bundle-Version=2.4

You can also create a wrap bundle for a third party dependency.
This bundle is simply a Maven POM that shades an existing jar and package into a jar bundle.

For instance, to create an OSGi bundle that wraps Apache Commons Lang, you can simply define the following Maven POM:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>osgi.commons-lang</groupId>
    <artifactId>osgi.commons-lang</artifactId>
    <version>2.4</version>
    <packaging>bundle</packaging>
    <name>commons-lang OSGi Bundle</name>
    <description>This OSGi bundle simply wraps commons-lang-2.4.jar artifact.</description>

    <dependencies>
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.4</version>
            <optional>true</optional>
        </dependency>
    </dependencies>

    <build>
        <defaultGoal>install</defaultGoal>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>1.1</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <artifactSet>
                            <includes>
                                <include>commons-lang:commons-lang</include>
                            </includes>
                        </artifactSet>
                        <filters>
                            <filter>
                                <artifact>commons-lang:commons-lang</artifact>
                                <excludes>
                                    <exclude>**</exclude>
                                </excludes>
                            </filter>
                        </filters>
                        <promoteTransitiveDependencies>true</promoteTransitiveDependencies>
                        <createDependencyReducedPom>true</createDependencyReducedPom>
                    </configuration>
                </execution>
            </executions>
        </plugin>
        <plugin>
            <groupId>org.apache.felix</groupId>
            <artifactId>maven-bundle-plugin</artifactId>
            <version>2.1.0</version>
            <extensions>true</extensions>
            <configuration>
                <instructions>
                    <Bundle-SymbolicName>manual</Bundle-SymbolicName>
                    <Export-Package>*</Export-Package>
                    <Import-Package></Import-Package>
                    <_versionpolicy>[$(version;==;$(@)),$(version;+;$(@)))</_versionpolicy>
                    <_removeheaders>Ignore-Package,Include-Resource,Private-Package,Embed-Dependency</_removeheaders>
                </instructions>
                <unpackBundle>true</unpackBundle>
            </configuration>
        </plugin>
    </build>

</project>

You have now a OSGi bundle for commons-lang that you can deploy directly:

root@karaf> osgi:install -s mvn:osgi.commons-lang/osgi.commons-lang/2.4

Some more information is available at http://gnodet.blogspot.com/2008/09/id-like-to-talk-bit-about-third-party.html, http://blog.springsource.com/2008/02/18/creating-osgi-bundles/ and http://felix.apache.org/site/apache-felix-maven-bundle-plugin-bnd.html.

Shell syntax

Easy to use interactively - no unnecessary syntax

// simple command
karaf@root> echo hello world
hello world

// session variables
karaf@root> msg = "hello world"
hello world
karaf@root> echo $msg
hello world

// execution quotes () - similar to bash backquotes
karaf@root> (bundle 1) location
mvn:org.ops4j.pax.url/pax-url-mvn/1.1.3

List, maps, pipes and closures

// lists - []
karaf@root> list = [1 2 a b]
1
2
a
b

karaf@root> map = [Jan=1 Feb=2 Mar=3]
Jan                 1
Feb                 2
Mar                 3

// pipes
karaf@root> bundles | grep felix
000000 ACT org.apache.felix.framework-3.0.2
000005 ACT org.apache.felix.configadmin-1.2.4
000006 ACT org.apache.felix.fileinstall-3.0.2

// closures - {}
karaf@root> echo2 = { echo xxx $args yyy }
org.apache.felix.gogo.runtime.shell.Closure@2ffb36c2
karaf@root> echo2 hello world
xxx hello world yyy

Leverages existing Java capabilities, via reflection

// exception handling - console shows summary, but full context available
karaf@root> start xxx
Error executing command osgi:start: unable to convert argument ids with value '[xxx]' to type java.util.List<java.lang.Long>
karaf@root> $karaf.lastException printStackTrace
org.apache.felix.gogo.commands.CommandException: Unable to convert argument ids with value '[xxx]' to type java.util.List<java.lang.Long>
	at org.apache.felix.gogo.commands.basic.DefaultActionPreparator.prepare(DefaultActionPreparator.java:347)
	at org.apache.felix.gogo.commands.basic.AbstractCommand.execute(AbstractCommand.java:34)
	at org.apache.felix.gogo.runtime.shell.CommandProxy.execute(CommandProxy.java:50)
	at org.apache.felix.gogo.runtime.shell.Closure.execute(Closure.java:229)
	at org.apache.felix.gogo.runtime.shell.Closure.executeStatement(Closure.java:162)
	at org.apache.felix.gogo.runtime.shell.Pipe.run(Pipe.java:101)
	at org.apache.felix.gogo.runtime.shell.Closure.execute(Closure.java:79)
	at org.apache.felix.gogo.runtime.shell.CommandSessionImpl.execute(CommandSessionImpl.java:71)
	at org.apache.karaf.shell.console.jline.Console.run(Console.java:169)
	at java.lang.Thread.run(Thread.java:637)
Caused by: java.lang.Exception: Unable to convert from [xxx] to java.util.List<java.lang.Long>(error converting collection entry)
	at org.apache.aries.blueprint.container.AggregateConverter.convertToCollection(AggregateConverter.java:318)
	at org.apache.aries.blueprint.container.AggregateConverter.convert(AggregateConverter.java:159)
	at org.apache.karaf.shell.console.commands.BlueprintCommand$BlueprintActionPreparator.convert(BlueprintCommand.java:73)
	at org.apache.felix.gogo.commands.basic.DefaultActionPreparator.prepare(DefaultActionPreparator.java:344)
	... 9 more
Caused by: java.lang.NumberFormatException: For input string: "xxx"
	at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
	at java.lang.Long.parseLong(Long.java:410)
	at java.lang.Long.valueOf(Long.java:525)
	at org.apache.aries.blueprint.container.AggregateConverter.convertFromString(AggregateConverter.java:261)
	at org.apache.aries.blueprint.container.AggregateConverter.convert(AggregateConverter.java:151)
	at org.apache.aries.blueprint.container.AggregateConverter.convertToCollection(AggregateConverter.java:316)
	... 12 more

// add all public methods on java.lang.System as commands:
karaf@root> addcommand system (loadClass java.lang.System)
karaf@root> system:getproperty karaf.name
root

// create new objects
karaf@root> map = (new java.util.HashMap)
karaf@root> $map put 0 0
karaf@root> $map
0                   0