In the current project one of my tasks was to simplify the maven release process. This should be a simple one click solution, that satisfies following requirements:

• Release has to be executed either from IDE or from the command line.
• Everyone (not only developer) should be able to execute release.
• It should hide the pain of executing multiple maven goals (release:prepare, release:perform) after each other.
• After releasing the software released artifacts for all profiles specified in the pom.xml should be deployed to the company’s maven repository.

I decided to write a simple Ant script that internally makes use of Maven Ant Tasks.

First a target asking user for all required release informations was born:

<?xml version="1.0" encoding="UTF-8"?>
<project name="myprj" default="release" xmlns:artifact="antlib:org.apache.maven.artifact.ant">
	<property environment="env" />
	<path id="maven-ant-tasks.classpath" path="maven-ant-tasks-2.1.3.jar" />
	<typedef resource="org/apache/maven/artifact/ant/antlib.xml"
               uri="antlib:org.apache.maven.artifact.ant" classpathref="maven-ant-tasks.classpath" />
 
	<!-- - - - - - - - - - - - - - - - - - 
          target: prerequisites                      
         - - - - - - - - - - - - - - - - - -->
	<target name="prerequisites">
		<fail unless="env.MAVEN_HOME" 
		    		message="Environment variable MAVEN_HOME was not found on your system!" />
	</target>

	<!-- - - - - - - - - - - - - - - - - - 
          target: input                      
         - - - - - - - - - - - - - - - - - -->
	<target name="input">
		<artifact:pom id="local.pom" file="pom.xml" />
		<script language="javascript">
		<![CDATA[	
		    var before = project.getProperty("local.pom.version");
		    project.setProperty("tmp.release.version", before.replaceAll("-SNAPSHOT", ""));
			
		    var tmpVersion = project.getProperty("tmp.release.version");
		    var nextVersionNo = tmpVersion.substr( tmpVersion.lastIndexOf(".") + 1 );
		    project.setProperty("tmp.next.version", 
			      tmpVersion.substr(0, tmpVersion.lastIndexOf(".") + 1) + 
			      (parseInt(nextVersionNo)+1) + 
			      "-SNAPSHOT"
		    );
		]]>
		</script>

		<input message="Please enter the project release version?" 
			defaultvalue="${tmp.release.version}" addproperty="prj.release.version" />
		<input message="Please enter the svn tag name?" 
			defaultvalue="${local.pom.artifactId}-${prj.release.version}" addproperty="prj.release.tag" />
		<input message="Please enter the project next version?" 
			defaultvalue="${tmp.next.version}" addproperty="prj.next.version" />

		<fail unless="prj.release.version" message="Property 'prj.release.version' was not defined!" />
		<fail unless="prj.release.tag" message="Property 'prj.release.tag' was not defined!" />
		<fail unless="prj.next.version" message="Property 'prj.next.version' was not defined!" />
	</target>
</project> 

The “input”-target uses <artifact:pom … /> task and offers the POM structure to the ant script. 

Furthermore it makes use of Ant’s possibility to embed javascript, that reads current artifact version from the POM and pre-set some default variables like release version, release tag and next development version.

Finally the second target specifies the release procedure:

<target name="release" depends="prerequisites, input" description="project release ant script">
	<artifact:mvn mavenHome="${env.MAVEN_HOME}" fork="true">
		<arg value="--batch-mode" />
		<arg value="-Dtag=${prj.release.tag}" />
		<arg value="-DreleaseVersion=${prj.release.version}" />
		<arg value="-DdevelopmentVersion=${prj.next.version}" />
		<arg value="clean" />
		<arg value="release:prepare" />
		<arg value="release:perform" />
	</artifact:mvn>

	<available file="target/checkout" type="dir" property="checkout.dir.present" />
	<fail unless="checkout.dir.present" message="Checkout directory 'target/checkout' is not present!" />

	<!-- deploy 'test1' profile -->
	<artifact:mvn mavenHome="${env.MAVEN_HOME}" pom="target/checkout/pom.xml" fork="true">
		<arg value="-Ptest1" />
		<arg value="clean" />
		<arg value="deploy" />
	</artifact:mvn>

	<!-- deploy 'test2' profile -->
	<artifact:mvn mavenHome="${env.MAVEN_HOME}" pom="target/checkout/pom.xml" fork="true">
		<arg value="-Ptest2" />
		<arg value="clean" />
		<arg value="deploy" />
	</artifact:mvn>		
	
	<!-- deploy 'prod' profile -->
	<artifact:mvn mavenHome="${env.MAVEN_HOME}" pom="target/checkout/pom.xml" fork="true">
		<arg value="-Pprod" />
		<arg value="clean" />
		<arg value="deploy" />
	</artifact:mvn>
</target> 

Because it is just a simple ant script, it can be executed either directly from your favorite IDE

or from the command line tool by calling: ant -f release.xml

Note! maven-ant-tasks-2.1.3.jar file has to be commited to the SCM together with the release.xml