This is a new cool feature I worked on with Brian and it’s coming on 6.1 as well as 6.0 EE SP2 and 5.2 EE SP6. With this feature you can add new struts actions to portal from a hook plugin and you can override any existing action with it.

There are two interfaces com.liferay.portal.kernel.struts.StrutsAction and com.liferay.portal.kernel.struts.StrutsPortletAction. The StrutsAction is used for regular struts actions like /c/portal/update_password and StrutsPortletAction is used for those that are used from portlets.

Let’s create a new simple hook to test it out. This hook will create a new struts path /c/portal/sample and wraps an existing struts action. Start by creating a new hook plugin in your plugins SDK. I’ll call it sample-struts-action.

./create.sh sample-struts-action

Next edit the liferay-hook.xml and add following fragment:

<?xml version="1.0"?>
<!DOCTYPE hook PUBLIC "-//Liferay//DTD Hook 6.1.0//EN" "http://www.liferay.com/dtd/liferay-hook_6_1_0.dtd">

<hook>
	<portal-properties>portal.properties</portal-properties>
	<custom-jsp-dir>/META-INF/custom_jsps</custom-jsp-dir>
	<struts-action>
		<struts-action-path>/portal/sample</struts-action-path>
		<struts-action-impl>com.liferay.samplestrutsaction.hook.action.SampleStrutsAction</struts-action-impl>
	</struts-action>
	<struts-action>
		<struts-action-path>/message_boards/view</struts-action-path>
		<struts-action-impl>com.liferay.samplestrutsaction.hook.action.SampleStrutsPortletAction</struts-action-impl>
	</struts-action>
</hook>

Next we need to create the struts action like below:

package com.liferay.samplestrutsaction.hook.action;

import com.liferay.portal.kernel.struts.BaseStrutsAction;
import com.liferay.portal.kernel.util.ParamUtil;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author Mika Koivisto
 */
public class SampleStrutsAction extends BaseStrutsAction {

	public String execute(
		HttpServletRequest request, HttpServletResponse response)
		throws Exception {

		String name = ParamUtil.get(request, "name", "World");

		request.setAttribute("name", name);

		return "/portal/sample.jsp";
	}

}

Next create the second Struts action. This one will actually wrap ViewAction of message boards portlet.

package com.liferay.samplestrutsaction.hook.action;

import com.liferay.portal.kernel.struts.BaseStrutsPortletAction;
import com.liferay.portal.kernel.struts.StrutsPortletAction;

import javax.portlet.ActionRequest;
import javax.portlet.ActionResponse;
import javax.portlet.PortletConfig;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse;
import javax.portlet.ResourceRequest;
import javax.portlet.ResourceResponse;

/**
 * @author Mika Koivisto
 */
public class SampleStrutsPortletAction extends BaseStrutsPortletAction {

	public void processAction(
			StrutsPortletAction originalStrutsPortletAction,
			PortletConfig portletConfig, ActionRequest actionRequest,
			ActionResponse actionResponse)
		throws Exception {

		originalStrutsPortletAction.processAction(
			originalStrutsPortletAction, portletConfig, actionRequest,
			actionResponse);
	}

	public String render(
			StrutsPortletAction originalStrutsPortletAction,
			PortletConfig portletConfig, RenderRequest renderRequest,
			RenderResponse renderResponse)
		throws Exception {

		System.out.println("Wrapped /message_boards/view action");

		return originalStrutsPortletAction.render(
			null, portletConfig, renderRequest, renderResponse);
	}

	public void serveResource(
			StrutsPortletAction originalStrutsPortletAction,
			PortletConfig portletConfig, ResourceRequest resourceRequest,
			ResourceResponse resourceResponse)
		throws Exception {

		originalStrutsPortletAction.serveResource(
			originalStrutsPortletAction, portletConfig, resourceRequest,
			resourceResponse);
	}

}

Then we need to create the JSP in docroot/META-INF/custom_jsps/html/portal/sample.jsp

Hello !

And lastly we need to create portal.properties in docroot/WEB-INF/src

auth.public.paths=/portal/sample

Now we are ready to deploy the plugin and see if it works. Just run ant deploy in your plugins sdk to deploy it.

You should see following in your tomcat console:

22:01:29,635 INFO  [AutoDeployDir:167] Processing sample-struts-action-hook-6.1.0.1.war
22:01:29,638 INFO  [HookAutoDeployListener:43] Copying web plugin for /Users/mika/Development/Liferay/git/bundles/deploy/sample-struts-action-hook-6.1.0.1.war
  Expanding: /Users/mika/Development/Liferay/git/bundles/deploy/sample-struts-action-hook-6.1.0.1.war into /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299
  Copying 1 file to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299/WEB-INF/classes
  Copying 1 file to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299/WEB-INF/classes
  Copying 1 file to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299/WEB-INF
  Copying 1 file to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299/META-INF
  Copying 12 files to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/webapps/sample-struts-action-hook
  Copying 1 file to /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/webapps/sample-struts-action-hook
  Deleting directory /Users/mika/Development/Liferay/git/bundles/tomcat-6.0.29/temp/20110117220130299
22:01:30,486 INFO  [HookAutoDeployListener:49] Hook for /Users/mika/Development/Liferay/git/bundles/deploy/sample-struts-action-hook-6.1.0.1.war copied successfully. Deployment will start in a few seconds.
Jan 17, 2011 10:01:39 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory sample-struts-action-hook
22:01:39,727 INFO  [PluginPackageUtil:1080] Reading plugin package for sample-struts-action-hook
22:01:39,759 INFO  [HookHotDeployListener:432] Registering hook for sample-struts-action-hook
22:01:39,770 INFO  [HookHotDeployListener:717] Hook for sample-struts-action-hook is available for use

Now try to access http://localhost:8080/c/portal/sample. It will ask you to sign in and once you sign in you should see the message Hello World! in your browser. You can add a paramer name to the url to change the message. If you access message boards it will print the message “Wrapped /message_boards/view action” in tomcat console and continue to render message boards as if nothing was changed.

Now our sample was really simple one. The return value from the execute method is the view where the request is dispatched next. This can be path to JSP, an existing struts forward or tiles definition. Returning null means that your action has handled the view already. Now you could try to return for instance portal.terms_of_use to display the terms of use.

You can download this sample plugin from svn://svn.liferay.com/repos/public/plugins/trunk/hooks/sample-struts-action-hook. The username is guest and password is empty.

UPDATE: We changed the API so that the original action is passed in so that you can also wrap it with your own logic instead of replacing. I also added a new hook property auth.public.paths so it allows you to set new public paths from hooks. I also added a StrutsPortletAction into to the sample and that demonstrates wrapping an existing action.

That’s a question I’ve head many times and in this post I will show you  just how to do that. These instructions are for Liferay 6 CE GA3 Tomcat 6.0 bundle however you can use any app server supported by Terracotta but the location and some configuration might be slightly different. So to get started you need to download:

• Liferay Portal 6 GA3 bundled with Tomcat
• Terracotta 3.3.0 open source edition

Next step is to install Liferay and Terracotta. For the purposes of this post I won’t go into great detail with the installation as both Terracotta and Liferay has good documentation. Basically the installation consist of unpacking the packages to a directory. From now on I will refer to those locations as LIFERAY_HOME and TERRACOTTA_HOME and inside LIFERAY_HOME we will have tomcat directory which I will refer as TOMCAT_HOME. Normally you would also install Liferay and Terracotta in separate servers but I will post a separate post addressing the recommended architecture. For now we can install everything on the same machine and run Terracotta with default configuration for development purposes.

Normally when clustering Liferay you need to address following components: EhCache and Hibernate, Quartz Scheduler, Document Library, Search Engine and optionally Session Replication. For Document Library and Search Engine Terracotta doesn’t offer anything new so you make those centrally available the same way as before. For example SAN for DL and SOLR for Search and Indexing. So we are left with EhCache and Hibernate, Quartz and Session Replication that we can address with Terracotta. 

EhCache and Hibernate Second Level Cache

1.  Remove ehcache.jar that is bundled with Liferay (located in TOMCAT_HOME/webapps/ROOT/WEB-INF/lib)
2. Copy all jars in TERRACOTTA_HOME/ehcache/lib to TOMCAT_HOME/webapps/ROOT/WEB-INF/lib
3. Copy TERRACOTTA_HOME/common/terracotta-toolkit-1.0-runtime-<version>.jar to TOMCAT_HOME/webapps/ROOT/WEB-INF/lib
4. Create my-ehcache folder to TOMCAT_HOME/webapps/ROOT/WEB-INF/classes
5. Create a hibernate-terracotta.xml and a liferay-multi-vm-terracotta.xml.
6. Adjust terracottaConfig in hibernate-terracotta.xml and liferay-multi-vm-terracotta.xml to point to your Terracotta servers. Like this: <terracottaConfig url=”localhost:9510″/>
7. Add following properties to your portal-ext.properties file:

   ehcache.multi.vm.config.location=/my-ehcache/liferay-multi-vm-terracotta.xml
   
net.sf.ehcache.configurationResourceName=/my-ehcache/hibernate-terracotta.xml
   
hibernate.cache.region.factory_class=net.sf.ehcache.hibernate.EhCacheRegionFactory

Quartz

1. Remove quartz.jar that is bundled with Liferay (located in TOMCAT_HOME/webapps/ROOT/WEB-INF/lib)
2. Copy TERRACOTTA_HOME/quartz/quartz-terracotta-<version>.jar and quartz-all-<version>.jar to TOMCAT_HOME/webapps/ROOT/WEB-INF/lib
3. Add following properties to your portal-ext.properties:

   org.quartz.jobStore.class = org.terracotta.quartz.TerracottaJobStore
   
org.quartz.jobStore.tcConfigUrl = localhost:9510

4. Extract portal.properties from portal-impl.jar and place it in TOMCAT_HOME/webapps/ROOT/WEB-INF/classes
5. Comment out following properties in portal.properties

   #org.quartz.jobStore.dataSource=ds

   #org.quartz.jobStore.isClustered=false
   
#org.quartz.jobStore.misfireThreshold=60000
   
#org.quartz.jobStore.tablePrefix=QUARTZ_
   
#org.quartz.jobStore.useProperties=false

Session Replication

This is highly container specific so refer to Terracotta documentation for specific instructions. Following steps are for Tomcat 6.0.

1. Copy TERRACOTTA_HOME/sessions/terracotta-session-<version>.jar to TOMCAT_HOME/lib
2. Copy TERRACOTTA_HOME/common/terracotta-toolkit-1.0-runtime-<version>.jar to TOMCAT_HOME/lib
3. Edit TOMCAT_HOME/conf/Catalina/localhost/ROOT.xml and add following line right after <Context>

   
<Valve className="org.terracotta.session.TerracottaTomcat60xSessionValve" tcConfigUrl="localhost:9510"/>

Testing The Configuration

Testing your configuration is simple:

1. Startup your Terracotta Server

   TERRACOTTA_HOME/bin/start-tc-server.sh

2. Startup your Tomcat

   TOMCAT_HOME/bin/startup.sh

3. Before Tomcat has fully started you should see following lines in your Tomcat console log:

   2010-09-01 21:35:40,059 INFO - Terracotta 3.3.0, as of 20100716-140706 (Revision 15922 by cruise@rh5mo0 from 3.3)
   2010-09-01 21:35:40,566 INFO - Successfully loaded base configuration from server at 'localhost:9510'.

4. Now browse http://localhost:8080 to verify that your portal is running. 
5. Now launch Terracotta Developer Console to verify that EhCache, Hibernate, Quartz and Sessions are seen by Terracotta. You can launch dev console with following command:

   TERRACOTTA_HOME/bin/dev-console.sh

6. Once you are connected to your Terracotta you should see Ehcache, Hibernate, Quartz and Sessions under My application which indicates that all of them are connected and recognized by Terracotta. Now you can use Dev Console to see what’s inside your cache or session. 

Closing Remarks

Now as you can see it is quite easy the cluster Liferay with Terracotta express installation. Now if you want to use the DSO approach it is whole another beast as it involves tedious instrumentation. If you are a Liferay EE customer and want to get supported version of both Liferay and Terracotta contact your Liferay sales rep and ask about Liferay Terracotta Edition. 

Freemarker is a template language very similar to Velocity. Starting from Liferay 6.0 Liferay supports also Freemarker templates in themes and Web Content templates. In this post I will show how you can use Freemarker in your themes.

Getting started

To get started you’ll need Liferay Portal 6.0 GA3 as well as corresponding Plugins SDK. Once you have setup your Portal and Plugins SDK we can start by creating a new theme plugin in PLUGINS_SDK_ROOT/themes folder.

To create the theme issue following command:

./create.[sh|bat] my-freemarker "My Freemarker"

Then go to my-freemarker-theme directory and open build.xml in your favorite editor.

In build.xml add theme.type property with value ftl above theme.parent property like this:

<property name="theme.type" value="ftl"></property>
<property name="theme.parent" value="_styled"></property>

Then you need to create docroot/WEB-INF/liferay-look-and-feel.xml with following contents:

<?xml version="1.0"?>
<!DOCTYPE look-and-feel PUBLIC "-//Liferay//DTD Look and Feel 6.0.0//EN" "http://www.liferay.com/dtd/liferay-look-and-feel_6_0_0.dtd">

<look-and-feel>
	<compatibility>
		<version>6.0.0+</version>
	</compatibility>
	<theme id="my-freemarker-theme" name="My Freemarker">
		<template-extension>ftl</template-extension>
	</theme>
</look-and-feel>

Now you run:

ant deploy

Congratulations you’ve just made your first Freemarker based theme. Now you can override base theme files in docroot/_diffs folder just as you would normally except template files now have extension .ftl instead of .vm.

Freemarker syntax

Freemarker syntax is slightly different from Velocity and it is much more strict. With Freemarker you won’t be able to get a way with trying to use undefined variables and you should also note that null value means it’s undefined. To test if value exists you can use double question mark after the variable name like this:

<#if someVariableName??>
Variable exists
</#if>

For full syntax reference check out Freemarker website.

Pre-defined theme variables

Most of the variables present for Velocity templates are also available for Freemarker templates. Only Velocity specific tools were removed you can accomplish everything and more with Freemarker build-ins. Here’s some examples how to format a java.util.Date type variable with Freemarker build-ins:

${lastUpdated?string("yyyy-MM-dd HH:mm:ss zzzz")}
${lastUpdated?string("EEE, MMM d, ''yy")}
${lastUpdated?string("EEEE, MMMM dd, yyyy, hh:mm:ss a '('zzz')'")}

You can find all the variables available for Freemarker templates from com.liferay.portal.freemarker.FreeMarkerVariables class and docroot/html/themes/_unstyled/init.ftl

Macro libraries

Most of the macros available to Velocity templates are also available for Freemarker templates. The only difference is the syntax how they are used. We provide a macro library with namespace liferay so that it won’t get mixed with your own macros. You can take a look at portal-impl/src/FTL_liferay.ftl to see full list of macros and use it as an example to build your own macros. Here are some commonly used macros:

<@liferay.css file_name=“some.css” />

<@liferay.js file_name=“some.js” />

<@liferay.language key=“my-key” />

<@liferay.breadcrumb />

<@liferay.docbar /> 

Tag libraries

Yes, you read it correctly. You can use taglibs in your Freemarker templates. This is something unique to Freemarker and it is limited to only templates in themes. To import a portal taglib to your template just add following line to your template:

<#assign aui=PortalJspTagLibs["/WEB-INF/tld/liferay-aui.tld"]>

Now you can use any tag within that taglib just if it was a macro library. Here’s an example how to add a Alloy UI input field:

<@aui.input name=“aStringLiteral” label=“Test” />

Have fun trying this out and if you find any glitches do report them to our issue tracker.