Maven assembly descriptor properties

Question

I want to pack two or more very similar distributions, the only difference is path to data set that will be inside those distributions.

Given this example for path: ${project.basedir}/src/config/dataset1

<?xml version="1.0" encoding="UTF-8"?>
<assembly xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2 http://maven.apache.org/xsd/assembly-1.1.2.xsd">

    <id>dataset1</id>
    <formats>
        <format>zip</format>
    </formats>

    <fileSets>
        <fileSet>
            <directory>${project.basedir}/src/config/dataset1/aaa</directory>
            <outputDirectory>conf/aaa</outputDirectory>
        </fileSet>
        <fileSet>
            <directory>${project.basedir}/src/config/dataset1/bbb</directory>
            <outputDirectory>conf/bbb</outputDirectory>
        </fileSet>
    </fileSets>

    <!-- MANY MORE FILESETS... -->

</assembly>

Now I want exactly the same assembly descriptor for different data set, for example: ${project.basedir}/src/config/dataset2

Off course I could create two assembly descriptors. But then again I would have to keep in mind to change multiple places when needed, or worse when adding another dataset or two.

Is there a way how solve this, like creating multiple executions and passing properties to it? Or something ever nicer?

EDIT: This wish item would solve everything: https://jira.codehaus.org/browse/MASSEMBLY-445

Answer 1

Yes, you could use properties for this.

1. Create properties (with default value) for parts that differs between executions in pom.xml. E.g.:

<properties>
    <dataset.dir>config/dataset</dataset.dir>
</properties>

2. Use them in your assembly descriptor just like any other property (e.g ${project.basedir} )

3. For different executions you could:

   • use several build profiles (Maven profiles) where override property value;

   • or pass values directly as a mvn call argument (like mvn package -Dprop=val)

Also, if you want to use these properties in any other place, you could populate them via placeholders in any config by using other maven plugins (for instance, maven-resource-plugin).