clawplach / el-profile-activator-extension

Support for expression languages in profile activation in Maven

EL Profile Activation Maven Extension

Allows profile to be activated using an expression language expression. Currently supports MVEL2 only. Extension hijacks property activation and tries to evaluate mvel expression first, if this is not successful it passes control to original property activator.

In order to activate extension, you cannot include it into <build><extensions> element, because profile activation is done before it would be activated. So you need to copy following files into $MAVEN_HOME/lib/ext:

• el-profile-activator-extension.jar (available in target directory)
• mvel2-${version} (available http://search.maven.org/#search%7Cgav%7C1%7Cg%3A%22org.mvel%22%20AND%20a%3A%22mvel2%22, substitute with latest version)

To profit from new activation, add following in your pom.xml:

<profile>
    <id>my-profile</id>

    <activation>
        <property>
        	<!-- mvel property name is obligatory -->
            <name>mvel</name>
            <value>isdef foo &amp;&amp; foo=="abc"</value>
        </property>
    </activation>
</profile>            

A few examples (an MVEL cheatsheet)

• Check if foo and bar are defined and have same value

    isdef foo && isdef bar && foo==bar
  

• Check if foo is defined while bar is not

    isdef foo && !isdef bar
  

• Check if foo starts with abc or baz contains xyz

    isdef foo && foo.startsWith("abc")) || (isdef baz && baz.contains("xyz"))
  

Complete MVEL reference guide is available at http://mvel.codehaus.org/Language+Guide+for+2.0