Introduction
Explain diff between std jbi component and lw component and the static use of ServiceMix.
See http://docs.codehaus.org/display/SM/What+is+a+lightweight+component This document discusses how to package and deploy a lightweight component to the ServiceMix lightweight container (
servicemix-lwcontainer
). The ServiceMix lightweight container is a service engine JBI component whose purpose is to allow lightweight components (POJOs) to be deployed at runtime rather than only deploying them statically via the servicemix.xml
file. Please see What is a Lightweight Component for a good explanation of the different types of JBI components.
Two As explained in What is a Lightweight Component there are two main use cases for ServiceMix:
1. As a ull full JBI container - using SMX ServiceMix as a full JBI container in which you can deploy Service Assemblies and standard JBI components. And you may also deploy lightweight components in this mode - they must be deployed to the servicemix-lwcontainer
.
2. Embedded - static servicemix.xml file this is a static configuration used mainly for testing or perhaps for encapsulating ServiceMix into a web application as the entire use of ServiceMix. In other words, you will not be able to deploy other stuff onto . This uses the servicemix.xml
file to configure components thare are only deployed when ServiceMix is started, not at runtime. You cannot deploy service units to this type of ServiceMix configuration at runtime. You would have to shutdown, reconfigure and then restart.
This tutorial focuses on deploying lightweight components to the servicemix-lwcontainer.
First some background. Just a brief background: A JBI component is either a service engine (SE) or a binding component (BC). These terms are defined in Introduction to ESB and/or the Glossary. A BC/SE is installed on ServiceMix by copying it into the install
directory which resides under the ServiceMix home directory. So what gets deployed? JBI components can act as containers themselves. Artifacts can be deployed to an existing BC or SE to add more functionality to that component. Adding artifacts to installed components is called deployment. To deploy artifacts to a component the artifacts can be placed in the deploy
directory under the ServiceMix home directory. Another A term that is important to know is service assembly. A service assembly is a collection of deployment artifacts and metadata. A service unit is a single deployment artifact which is deployed on a single component. For deployment to happen, the artifacts must be in a very specific format, which is specified in the JSR 208 specification. Please see chapter 6 of the JSR 208 specification for more details. In addition to deploying components, ServiceMix allows servicemix.xml
files to be deployed in a similar method to deploying a component. ]
Manually Creating
...
a Service Unit and Service Assembly
...
We are going to use the existing ServiceMix Loan Broker example, which can be found Loan Broker Demo for ServiceMix, as the basis for this discussion.
There are several things to note about this example. First of all it is meant to be run stand-alone. Specifically, when running this example, ServiceMix will be started for you, then the loan broker is deployed and run. Therefore, there is a servicemix.xml
file in the loan-broker
directory. This servicemix.xml
file is used for configuring the ServiceMix JBI container upon ServiceMix starting up. This is not to be confused with the servicemix.xml
located in the loan-broker\src\su
directory. The SU servicemix.xml
file is used to configure the servicemix-lwcontainer
. Every service unit must contain some kind of configuration file. For example, if we were creating a service unit for the BPEL service engine there would also be a configuration file, but it would not be a servicemix.xml
file, such as the one used for configuring the lightweight container.
NOTE: There are two major phases to creating a lightweight component that is ready for deployment: one, is the development phase of the component, which includes coding and compiling and building the code, the second phase is creating the packaging necessary for the component to be installed onto the JBI container. This document will focus on the second part. Any steps relating to compilation are simply performed here to get us to the point that we can assemble the component into a JBI service assembly or service unit.
In general, there are three steps to creating the SA and deploying it to the ServiceMix container.
The following example shows several lightweight components (which make up the loan broker example) being deployed.
- Create the service units.
- Create the service assemblies.
- Deploy the service assemblies to their respective components in the JBI container.
The following provides details on each step above using the loan-broker example to illustrate.These steps were performed with a source distribution of ServiceMix 3.x on Windows XP.
Although we are not covering the component development phase, in this case we do need to perform a compile. We will use Apache Ant to compile the loan-broker demo components:
Code Block |
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cd [servicemix_dir]\examples\loan-broker ant build-components |
This will compile the Java code and put the Java class files into the {{\ Wiki Markup [servicemix_dir
\]\examples\loan-broker\build\loanbroker\components
}} directory.
Now we are ready to assemble the lightweight components together. The loan broker demo supplies us with a build.xml
file (which was used in the compile step above). The build.xml
contains targets for creating service units and service assemblies. If you run "ant setup" a service unit and service assembly will automatically be created. Ultimately, this is what you will want to do, however, the following procedure gives the manual steps for creating a service unit and service assembly, to facilitate in understanding the contents of a SUs and SAs.
- First create the service unit. The service unit is a ZIP file that will contain your application's Java class files . For example:
and theservicemix.xml
configuration file. The service unit can also contain ajbi.xml
which provides information about services statically provided and consumed. In ServiceMix it is optional to include this file. In the case of our example, we have not included it.- Use a ZIP compression tool, such as Winzip or gzip to create a zip file containing the classes in [servicemix_dir
Use a ZIP compression tool, such as Winzip or gzip to create a zip file containing the classes in \[servicemix_dir\]\examples\loan-broker\build\loanbroker\components . The zip file name is arbitrary, but to match the example call it {{and theWiki Markup servicemix.xml
file which can be found in[servicemix_dir]\src\su
. The zip file name is arbitrary, but it is used in the Service Assembly'sjbi.xml
file, so to match the example call itloanbroker-su.zip
}}. \\ Put the {{Wiki Markup loanbroker-su.zip
}} file in the {{\[servicemix_dir
\]\examples\loan-broker\build
}} directory for later use. Note: you may store the zip file anywhere. \\ \\ The above two steps can be done automatically using the ant script: "ant
The above two steps can be done automatically using the ant script: "ant build-su". If you look in the {{build.xml
}} file you will see the {{build-su
}} target does exactly what we just did manually. \\
- Use a ZIP compression tool, such as Winzip or gzip to create a zip file containing the classes in [servicemix_dir
- Create the Service Assembly.
--------------------------------------------------------------------------------------
- A service assembly is a zip file containing one or more service units and a
jbi.xml
file. Thejbi.xml
file must be in theMETA-INF
directory. you may also include other files in theMETA-INF
directory. The ZIP file directory structure for our example looks like this:Code Block loanbroker-su.zip META-INF\ jbi.xml LICENSE.txt DISCLAIMER.txt
Thejbi.xml
looks like this:
Two jar files must be created. These jar files will be copied into the ServiceMixCode Block <?xml version="1.0" encoding="UTF-8"?> <jbi xmlns
deploy
directory. The first jar file will contain the service componentjbi.xml
file. When this is copied to thedeploy
directory it deploys theServiceMixComponent
component. The second jar file will contain the service assembly and thejbi.xml
descriptor file. When it is copied to thedeploy
directory of ServiceMix it deploys the service unit (Quartz) to the previously deployed component,ServiceMixComponent
. - The file service component
jbi.xml
file should contain:Code Block <jbi xmlns="http://java.sun.com/xml/ns/jbi" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/jbi" version="1.0"> <component type="service-engine"> <identification> <name>servicemix-component</name> <description>A ServiceMix Component that can be used to deploy servicemix.xml artifacts.</description> </identification> <component-class-name>org.servicemix.components.servicemix.ServiceMixComponent</component-class-name> <component-class-path/> </component> </jbi>
- Put
jbi.xml
in an empty META-INF directory and put that into a jar file:Code Block mkdir META-INF copy jbi.xml META-INF jar cvf service-component.jar *
- Create a zip file of the
servicemix.xml
file you modified above. The zip file should contain theservicemix.xml
file and it should be called su1.zip to match the name it is called in thejbi.xml
file. See theartifacts-name
tag in thejbi.xml
file for the name of the zip file. Create the second jar file--this is the service assembly jar file. It will contain another - The final step is to deploy the service assembly to the JBI container. To do this copy the
loanbroker-sa.zip
file to the[servicemix_dir]\deploy
directory. If ServiceMix is already running it will detect the file is there and start it. If ServiceMix is not running, start it to see the example start running:Code Block ..\..\bin\servicemix servicemix.xml
jbi.xml
file that is used for the service assembly and it will also contain the zip file, su1.zip
in the following structure:The service assembly
jbi.xml
should be match the following: ="http://java.sun.com/xml/ns/jbi" |
version="1.0">
|
<service-assembly>
<identification>
|
<name>loanbroker</name> |
<description>LoanBroker Service |
Assembly</description> </identification> <service-unit> <identification> |
<name>loanbroker</name> <description>LoanBroker Service |
Unit</description> </identification> <target> <artifacts-zip>loanbroker- |
su.zip</artifacts-zip> <component-name>servicemix- |
lwcontainer</component-name> </target> </service-unit> </service-assembly> |
</jbi>
|
The interesting thing to note is that the
jbi.xml
file to an empty META-INF directory, then create the jar file: Code Block |
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In a directory which contains these files, create the jar file:
META-INF/jbi.xml
su1.zip
jar cvf sa_quartz.jar *
|
artifacts-name
tag) and the component to which it will be deployed is servicemix-lwcontainer
(see the <component-name> tag). There could be multiple service units in a service assembly and they would each be included in the jbi.xml
file with the same type of information for each. Create the service assembly ZIP file and include the
loanbroker-su.zip
file and the META-INF\jbi.xml
directory and file in it. To remain consistent with our example, call the zip file loanbroker-sa.zip
. Put the
loanbroker-sa.zip
file in the [servicemix_dir]\examples\loan-broker\build
directory for later use. Note: in a real world application you may store the zip file anywhere. Related Documentation
The JBI spec describes in detail how to create a valid JBI deployment unit. In essence, it is a jar file with a META-INF/jbi.xml with other resource jars inside it. Please see Deployment Units for more information.
Related Documentation
...
Please see JSR 208.
Spring Related information
Inside the servicemix.xml file, the ability to import the common beans using the following:
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<import resource="classpath:otherBeans.xml" />
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The resource is a SpringResource so the following also works:
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<import resource="file:path/to/file/jmx.xml" />
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if you run ServiceMix (or JBoss) with a param:
Code Block |
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JAVA_OPTS="-DMYHOME=somepath/"
JAVA_OPTS=-DMYHOME=somepath/ # windows
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then in the servicemix.xml and xbean.xml you can reference MYHOME.
eg:
Code Block |
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<import resource="file:${MYHOME}/path/to/file/jmx.xml" />
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Then you can also import a properties file from this same path to pull in other config you may need. (that you want outside an SU/SA bundle).
Code Block |
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<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<list>
<value>${MYHOME}/conf/config.properties"</value>
</list>
</property>
</bean>
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