How to skip the maven antrun copy/shade:shade goal dynamically?

Question

I am using maven for configuration of an application consisting of multiple small services. Most of the services developed in java share the same maven configuration, as in the same build lifecycle, some shared resources (like spring AMQP).

So I have organized the shared resources in a SuperPom.

While the shade plugin doesn't really seem to disturb the install process, the antrun plugin of course won't find any of the files it should copy, due to there not being created any jar files by the shade plugin.

As I'd like the configuration of the shade/antrun plugin to be abstracted in the SuperPom, I need to skip the shade/copy goal.

I have tried mvn clean install -Dmaven.shade.skip=true, mvn clean install -Dmaven.copy.skip=true, mvn clean install -Dmaven.shade.shade.skip=true

Here is a small sample for you to play with:

<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/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>Test</groupId>
    <artifactId>SuperTest</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>
    <properties>
        <log4j.version>1.2.17</log4j.version>
        <destination>pleasedeleteme</destination>
        <mainpackage>com.uk.cc.it.info.gov.test.xxx</mainpackage>
    </properties>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
            <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.ManifestResourceTransformer">
                                    <mainClass>${mainpackage}.Main</mainClass>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.8</version>
                <executions>
                    <execution>
                        <id>copy</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy</goal>
                        </goals>
                        <configuration>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>${groupId}</groupId>
                                    <artifactId>${artifactId}</artifactId>
                                    <version>${version}</version>
                                    <type>jar</type>
                                    <overWrite>true</overWrite>
                                    <outputDirectory>${destination}</outputDirectory>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
    <dependencies>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
        </dependency>
    </dependencies>

</project>

Answer 1

The maven-shade-plugin doesn't have a parameter to skip. Often the shade-plugin isn't there just for fun, so you might wonder if you really want to skip this. If you think it is still valid, you have to create a profile with activation like this:

<activation>
  <property>
    <name>skipShade</name>
    <value>!true</value>
  </property>
</activation>

This way it is activated by default, unless you add -DskipShade or -DskipShade=true.

Answer 2

Maven 3.6.1 gives you a new approach.

In the superPom you can define a profile for your shading configuration:

<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>Test</groupId>
<artifactId>SuperTest</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<properties>
    <log4j.version>1.2.17</log4j.version>
    <destination>pleasedeleteme</destination>
    <mainpackage>com.uk.cc.it.info.gov.test.xxx</mainpackage>
</properties>

<build>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.7</source>
                <target>1.7</target>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <version>2.8</version>
            <executions>
                <execution>
                    <id>copy</id>
                    <phase>package</phase>
                    <goals>
                        <goal>copy</goal>
                    </goals>
                    <configuration>
                        <artifactItems>
                            <artifactItem>
                                <groupId>${groupId}</groupId>
                                <artifactId>${artifactId}</artifactId>
                                <version>${version}</version>
                                <type>jar</type>
                                <overWrite>true</overWrite>
                                <outputDirectory>${destination}</outputDirectory>
                            </artifactItem>
                        </artifactItems>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>
<dependencies>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>${log4j.version}</version>
    </dependency>
</dependencies>

<profiles>
    <profile>
        <id>shade</id>
        <activation>
            <activeByDefault>false</activeByDefault>
        </activation>
        <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.ManifestResourceTransformer">
                                        <mainClass>${mainpackage}.Main</mainClass>
                                    </transformer>
                                </transformers>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </build>
    </profile>
</profiles>

In the user's settings.xml under .m2 you can add a profile of the same id to enable the shade profile configuration of your superPom. This gives you the option to simple toggling the shading from inside your IDE like Intellij IDEA (only tested in Intellij).

<settings xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
                          https://maven.apache.org/xsd/settings-1.0.0.xsd">

    ...

    <!-- toggle shading from inside Intellij IDEA -->
    <profiles>
        <profile>
            <id>shade</id>
        </profile>
    </profiles>

    <!-- Shade Profile has to be activeProfile to be 
    able to explicitly disable shading -->
    <activeProfiles>
        <activeProfile>shade</activeProfile>
    </activeProfiles>
</settings>

In the child project you can add a .mvn/maven.config file to your child project template to predefine shading for the project by default. (Requires a CVS template that is used to predefine a company standard.)

The approach using a maven.config is useful if some of your team members do not have the profile in their settings.xml file and you have to take care that shading will be done most of the time.

.mvn/maven.config:

-Pshading

The profile can also be activated by default using jenkinsfile for Jenkins by passing -Pshade. It will overwrite the maven.config setting. To disable use -P!shade

Please note if you are using maven.config file in Intellij (2020.2.2): The .mvn/maven.config file must exists in the subdirectory of the root aggregator pom folder. Building a subproject form the IDE does not respect a .mvn/maven.config file on the subproject level at the moment. Running a mvn command from the command line in the subproject folder will repespect both, the child project .mvn/maven.config and the parent .mvn/maven.config.

Answer 3

Disabling the maven shade plugin worked for me. The build was stock trying to produce the dependency reduced pom file before I disabled the Maven shade plugin.

Answer 4

The skip option was introduced in version 3.3.0 of the shade plugin, so now skipping can be done dynamically using, for example, properties:

  <properties>
    ....
    <skipShaded>true</skipShaded>
  </properties>

  ...
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>3.3.0</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <skip>${skipShaded}</skip>
              ...
            </configuration>
          </execution>
        </executions>
      </plugin>

In the above the default is to skip, and this can be overridden with passing -DskipShaded=false to mvn.

Answer 5

Did you try setting the phase of maven-shade-plugin to none in the super-pom and then overriding this in the client poms?

So in the parent pom:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>2.3</version>
    <executions>
        <execution>
            <id>shade</id>
            <phase>none</phase>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <!-- ... -->
            </configuration>
        </execution>
    </executions>
</plugin>

And in the child poms that need it:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <!-- no need to specify version -->
    <executions>
        <execution>
            <id>shade</id>
            <phase>package</phase>
            <!-- no need to specify configuration -->
        </execution>
    </executions>
</plugin>