Maven shade plugin does not merge files

Question

My goal is to merge two XML files (both named info.xml) which are in src/main/resources of two Maven modules (packaging:jar) into a target WAR archive.

proj1: contains src/main/resources/info.xml

proj2: contains src/main/resources/info.xml

web: web project which should contain a merged info.xml from proj1 and proj2. I declared the plugin in the web project:

<build>     
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>2.2</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <transformers>
                            <transformer
                                implementation="org.apache.maven.plugins.shade.resource.XmlAppendingTransformer">
                                <resource>info.xml</resource>
                            </transformer>
                        </transformers>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

To build the web project and its modules I have a build project with:

<modules>
    <module>proj1</module>
    <module>proj2</module>
    <module>web</module>
<modules>

I tried using a mvn clean package command in the build project and as result my web/target/web.war contains the unpacked libs (ueber.jar which I don't really want) and NO merged info.xml files.

What am I doing wrong?!

Answer 1

You have to configure Transformers to merge files, since it often requires extra logic, especially XML. See Resource Transformers for the details.