Using build-helper-maven-plugin

Question

I have the pom.xml below.

I'd like to pass a tag property to my build, using this command:

mvn clean package -Dtag=test

It should split this property into two others, my.group an my.version, and then use it in a URI to build an XLDeploy package, using the xldeploy-maven-plugin (https://docs.xebialabs.com/xldeploy-maven-plugin/6.0.x/).

My problem is that the regex-properties goal is actually doing the job, as I can see thanks to the maven-antrun-plugin:

[INFO] --- maven-antrun-plugin:1.1:run (default) @ myArtifactId ---
[INFO] Executing tasks
     [echo] Displaying value of 'my.group' property
     [echo] [my.group] group/test
     [echo] Displaying value of 'my.version' property
     [echo] [my.version] test

But the command grep fileUri target\deployit-working-dir\deployit-manifest.xml show that the vars in Uri does not get replaced:

grep fileUri target\deployit-working-dir\deployit-manifest.xml
      <fileUri>http://mynexus.ur/service/local/repositories/my-repo/content/${my.group}/anArtefact/${my.version}/anArtefact-1.0.zip</fileUri>

The POM is the following file:

<project xmlns="http://maven.apache.org/POM/4.0.0" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>myGroupId</groupId>
    <artifactId>myArtifactId</artifactId>
    <version>1.0</version>

    <packaging>dar</packaging>

    <build>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>build-helper-maven-plugin</artifactId>
                <version>3.0.0</version>
                <executions>
                    <execution>
                        <id>regex-properties</id>
                        <goals>
                            <goal>regex-properties</goal>
                        </goals>
                        <configuration>
                            <regexPropertySettings>
                                <regexPropertySetting>
                                    <name>my.group</name>
                                    <value>group/${tag}</value>
                                    <regex>(asm-[0-9]+)-([0-9]+.[0-9]+)-([0-9]+)$</regex>
                                    <replacement>$1</replacement>
                                    <failIfNoMatch>false</failIfNoMatch>
                                </regexPropertySetting>
                                <regexPropertySetting>
                                    <name>my.version</name>
                                    <value>${tag}</value>
                                    <regex>(asm-[0-9]+)-([0-9]+.[0-9]+)-([0-9]+)$</regex>
                                    <replacement>$1-SNAPSHOT</replacement>
                                    <failIfNoMatch>false</failIfNoMatch>
                                </regexPropertySetting>
                            </regexPropertySettings>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-antrun-plugin</artifactId>
                <version>1.1</version>
                <executions>
                    <execution>
                        <phase>validate</phase>
                        <goals>
                            <goal>run</goal>
                        </goals>
                        <configuration>
                            <tasks>
                                <echo>Displaying value of 'my.group' property</echo>
                                <echo>[my.group] ${my.group}</echo>
                                <echo>Displaying value of 'my.version' property</echo>
                                <echo>[my.version] ${my.version}</echo>
                            </tasks>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>com.xebialabs.xldeploy</groupId>
                <artifactId>xldeploy-maven-plugin</artifactId>
                <version>6.0.0</version>

                <extensions>true</extensions>

                <configuration>
                    <deployables>
                        <file.Folder name="file">
                            <scanPlaceholders>false</scanPlaceholders>
                            <fileUri>http://mynexus.ur/service/local/repositories/my-repo/content/${my.group}/anArtefact/${my.version}/anArtefact-${project.version}.zip</fileUri>
                        </file.Folder>
                    </deployables>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

I'm not quite sure if the build-helper-maven-plugin wrong, or anywhere else in my POM, or if it's simply lack of replacing properties in the xldeploy-maven-plugin...

Thanks for the help ;)

Answer 1

I checked the source of xldeploy-maven-plugin-6.0.1, and it seems it is the limitation of the current implementation.

The problem is that GenerateDeploymentPackageMojo does not rely on maven to do the substitution of the properties. Instead, it uses a custom AbstractConfigurationConverter named DeployitCIConverter (which delegates to MavenDeployableConverter) to convert the <deployables> node to a list of MavenDeployable)

This boils down to:

• you have the access to effective POM
• you don't have access to properties defined dynamically via build helper plugin

Of course the properties defined dynamically can be acessed in any mojo:

• if you use a parameter
• if you evaluate them manually via expression evaluator (check: get mojo parameters in maven plugin)

For the antrun plugin, it uses ExpressionEvaluator explicitely in the echo task. Informative article: Properties resolution in Maven and its implications on Antrun plugin

Ideas to fix the problem:

• do your group and version parsing in external script and pass the values to mvn command.
• create a cutom mojo extending GenerateDeploymentPackageMojo and preprocess deployables in the execute method (not that hard as it sounds).