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Maven jandex plugin does not generate index for local custom maven repositories (sometimes)

I have a multi module maven project wie quarkus modules and some custom libraries which are local maven repositories (so they can be used by the other maven projects/modules). However, so that local maven repositories are recognizable und usable by your other local maven projects, you have to manually index them for some reason. I.e. add a config like this for quarkus index to the application.properties of the project including the local maven repo dependency:
quarkus.index-dependency.<index-name>.group-id = <group-id-of-local-maven-repo>
quarkus.index-dependency.<index-name>.artifact-id = <artifact-id-of-local-maven-repo>
The problem is, this causes issues for me becausse if you have 3 layers of project dependencies, say:
Project A (custom local maven repo library)
Project B (custom local maven repo library, includes Project A dependency)
application.properties (indexing Project A library dependency)
Project C (Local maven project for an end product, includes Project B
library dependency - and through it indirectly Project A).
application.properties (indexing Project B library dependency and config for datasources or other app related things)
Then when you generate an uber-jar (fat jar) of Project C for deployment, it for some reason uses application.properties of Project B in the packaged jar, instead of from the project which im building (Project C). Thus, the app is missing key configs and does not work. Maven seems to use an inverse priority here, which i dont know if thats a bug or not. When i asked about this, i was simply told that:
"My dependencies should not have application.properties".
I tried to find a way to prevent manual indexing via application.properties and found the maven jandex plugin - which is supposed to generate an index. The next problem is, this seems to only work in some projects but not in others in the dependency hierarchy, resulting in the same situation as before, and i don't understand why. This is the pom.xml config for the plugin i have included in all 3 projects (the entire pom.xml for all is too long, so let me know if you need more info):
<properties>
...
<jandex.skip>false</jandex.skip>
...
</properties>
...
<build>
...
<plugin>
<groupId>io.smallrye</groupId>
<artifactId>jandex-maven-plugin</artifactId>
<version>3.0.5</version>
<inherited>true</inherited>
<executions>
<execution>
<id>make-index</id>
<goals>
<goal>jandex</goal>
</goals>
</execution>
</executions>
<configuration>
<skip>${jandex.skip}</skip>
</configuration>
</plugin>
...
The odd thing is, this works to the extend that i no longer have to index Project B library dependency in Project C application.properties, but Project B library dependency still has to manually index Project A library dependency - thus rendering the entire exercise futile. Project C having an application.properties was never the issue, and is obviously needed. Project B still requires a properties file to point to Project A now, how do i solve this?
I have a parent module POM in the root folder containing all these projects, over which this maven jandex dependency is distributed to all modules, so it looks like this:
Maven parent module (contains all dependencies and versions used by all project sub modules)
Project A (custom local maven library repo), own pom.xml with inheritance from parent module
Project B (custom local maven library repo, includes Project A library), own pom.xml with inheritance from parent module
application.properties - Indexes Project A dependency manually, this is the problematic one which needs to go!
Project C (Local maven project for REST API etc., includes Project B library), own pom.xml with inheritance from parent module
pom.xml (parent module POM, containing maven jandex dependepency among others)
Edit: One of the projects, "entity", where all the database access objects are stored, does not run the jandex plugin during mvn clean install. This is the POM of the project:
<?xml version="1.0" encoding="UTF-8"?>
<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>com.compamny.project</groupId>
<artifactId>entity</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>17</maven.compiler.source>
<maven.compiler.target>17</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-hibernate-orm</artifactId>
<version>2.16.1.Final</version>
</dependency>
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-hibernate-validator</artifactId>
<version>2.16.1.Final</version>
</dependency>
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-resteasy-reactive-jackson</artifactId>
<version>2.16.1.Final</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jdk8</artifactId>
<version>2.13.3</version>
</dependency>
<!-- https://mvnrepository.com/artifact/io.smallrye/jandex-maven-plugin -->
<dependency>
<groupId>io.smallrye</groupId>
<artifactId>jandex-maven-plugin</artifactId>
<version>3.0.0</version>
</dependency>
</dependencies>
<build>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.7.1</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
<plugin>
<groupId>io.smallrye</groupId>
<artifactId>jandex-maven-plugin</artifactId>
<version>3.0.0</version>
<inherited>true</inherited>
<executions>
<execution>
<id>make-index</id>
<goals>
<goal>jandex</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
When i force the execution of the jandex goal with mvn io.smallrye:jandex-maven-plugin:3.0.0:jandex it creates an META-INF/jandex.jdx file, but it does not produce one when i run mvn clean install. This is not a solution since i need to build the project, run the jandex plugin and install it into my local repositories separately. Also, notice that im using the "io.smallrye" version of the jandex plugin since the "org.jboss" version seems to not work at all.

I figured it out. The jandex plugin was set in the <pluginManagement> section of the POM configuration, which made it not run on mvn clean install. I had to move it to the plugins section so it gets executed. Thanks #Ladicek for making me look closer and keep trying!

neo4j procedure depending on signed jar (mapdb)

I have created a neo4j user-defined procedure. It also compiles and works in neo4j.
Recently though, I added a dependency to my procedure plugin that prevents neo4j from starting when I try to run the newly built jar. Concretely, I receive following exception at the bottom of the stack trace:
Caused by: java.lang.SecurityException: Invalid signature file digest for Manifest main attributes
The only thing I changed is to add MapDB to my dependencies. So I suspect that it depends on some signed artifact. As it turns out neo4j plugins are "uber-jars" (i.e., shaded jars) which doesn't work very well with signed dependencies.
I figured I could try to exclude MapDB from the shading by changing the scope to provided and additionally adding the mapdb jar to plugins folder of neo4j. So the plugins folder of neo4j now includes both mapdb.jar and myprocedure.jar.
This doesn't seem to work though: neo4j starts, but when calling my procedure I receive a ClassNotFound Exception.
Any ideas on how I can solve this dilemma? I really depend on something like MapDB as my graph is very large and keeping everything in my procedure in-memory regularly leads to memory exceptions.
Many thanks in advance!
The important part of my pom.xml should it help (I started off with the procedure template so it still looks quite similar):
<dependencies>
<!-- other dependencies that don't make a difference ... -->
<dependency>
<groupId>org.mapdb</groupId>
<artifactId>mapdb</artifactId>
<version>3.0.7</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.neo4j</groupId>
<artifactId>neo4j</artifactId>
<version>${neo4j.version}</version>
<scope>provided</scope>
</dependency>
<!-- Test Dependencies -->
<dependency>
<groupId>org.neo4j.test</groupId>
<artifactId>neo4j-harness</artifactId>
<version>${neo4j.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.neo4j.driver</groupId>
<artifactId>neo4j-java-driver</artifactId>
<version>1.4.2</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<!-- Neo4j Procedures require Java 8 -->
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<!-- This generates a jar-file with our procedure code,
plus any dependencies marked as `compile` scope.
This should then be deployed in the `plugins` directory
of each Neo4j instance in your deployment.
After a restart, the procedure is available for calling. -->
<artifactId>maven-shade-plugin</artifactId>
<version>2.4.3</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>

So, one solution that worked was to use the maven-assembly-plugin instead of the maven-shade-plugin. The assembly plugin creates a standalone jar with all dependencies without re-packaging all dependencies.
Of course, I had to remove the <scope>provided</scope> for mapdb so it is also included in the assembled jar.
The rest is just replacing the shade plugin with following snippet (thanks to this question here):
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
</plugin>
Afterwards I received another exception which I thought was due to a wrong signature:
Caused by: java.lang.VerifyError ...
Turns out this was just because I had another procedure in neo4j that uses the same dependencies as mapdb. Quick fix was to remove that procedure library.
Of course, there are also other solutions, including removing the signature, or re-signing it. However, I explicitly did not want to remove any signatures.

I'm not aware that neo4j is checking any jar signatures by default. I suspect the repackaging of mapdb artifact being the culprit.
To validate that, remove the shade or assembly plugin in and build a jar that solely contains your code. Copy that jar and the mapdb.jar into the plugin folder and observe logs during a restart.

Maven annotation processing processor not found

I'm new to annotation processing and I'm trying to automating it with Maven. I've put this in my pom.xml:
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<annotationProcessors>
<annotationProcessor>
co.aurasphere.revolver.annotation.processor.InjectAnnotationProcessor</annotationProcessor>
<annotationProcessor>
co.aurasphere.revolver.annotation.processor.RevolverContextAnnotationProcessor</annotationProcessor>
</annotationProcessors>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
The problem is that when I try to build the project I get a CompilationFailureException because Maven can't find the processors.
I've found other questions like this, solved by putting the dependency outside the plugin. I tried that, but nothing changed for me.
Am I missing something?
Thank you.
EDIT
Here is my dependency on another project which contains both the processor and the annotations:
<dependencies>
<dependency>
<groupId>co.aurasphere</groupId>
<artifactId>revolver-annotation-processor</artifactId>
<version>0.0.3-SNAPSHOT</version>
</dependency>
</dependencies>
EDIT 2:
After further investigation, I decided to decompile the processor JAR (built with Maven) and it happens that... my classes are not there. For some reasons, Maven is not compiling my classes into the JAR and that's why the classes are not found. I've tried figuring out what's wrong on that build (this never happened to me before and I've used Maven for a while...).
First of all, the packaging on that project is jar.
The classes are all under src/main/java.
I've checked in my pom.xml that the classpath and source path is the same.
Here's the processor pom:
<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>co.aurasphere</groupId>
<artifactId>revolver-annotation-processor</artifactId>
<version>0.0.3-SNAPSHOT</version>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<!-- https://mvnrepository.com/artifact/javax.inject/javax.inject -->
<dependency>
<groupId>javax.inject</groupId>
<artifactId>javax.inject</artifactId>
<version>1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.velocity/velocity -->
<dependency>
<groupId>org.apache.velocity</groupId>
<artifactId>velocity</artifactId>
<version>1.7</version>
</dependency>
</dependencies>
EDIT 3
Here's the output of a maven clean install on the processor project. Unfortunately the output is too long and I had to post an external link even if I know it's not good.
EDIT 4
Here are some screenshots of my dependency hierarchy: and .
Since the project was originally created as an Eclipse simple Java project and then converted to a Maven one, I tried to create a new Maven project and move everything to the new one in the hope that the problem was the Eclipse plugin that messed something up, but the error was still there.

This is an extended version of the accepted answer above provided by #Aurasphere. Hopefully this will give some explanation to how the proposed solution works.
First, some background to what is happening here. Say, we want a custom annotation processor. We implement it and put it into a JAR as Maven artefact, so that it could be consumed by other projects. When such projects are being compiled, we want our annotation processor to be recognised by Java compiler and used appropriately. To make this happen, one needs to tell the compiler about a new custom processor. Compiler looks in the resources and checks FQN of classes listed in META-INF/services/javax.annotation.processing.Processor file. It tries to find these classes in classpath and load them to run the processing of annotations used upon classes that are currently being compiled.
So, we want our custom class to be mentioned in this file. We can ask a user of our library to put this file manually, but this is not intuitive and users could be frustrated why the promised processing of annotation doesn't work. That's why we might want to prepare this file in advance and deliver it together with the processor inside JAR of our Maven artefact.
The problem is that if we simply put this file with FQN of the custom processor in it, it will trigger compiler during compilation of our artefact, and since the processor itself is not yet compiled, the compiler will show the error about it. So we need to skip annotation processing to avoid this. This can be done using -proc:none, or with Maven:
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<proc>none</proc>
</configuration>
</plugin>
We might have unit tests that will need our annotation processor. In Maven, test compilation is carried out after main sources are built, and all classes are already available including our processor. We just need to add special step during processing of test sources which would use our annotation processor. This can be done using:
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<executions>
<execution>
<id>process-test-annotations</id>
<phase>generate-test-resources</phase>
<goals>
<goal>testCompile</goal>
</goals>
<configuration>
<proc>only</proc>
<annotationProcessors>
<annotationProcessor>fully.qualified.Name</annotationProcessor>
</annotationProcessors>
</configuration>
</execution>
</executions>
</plugin>

I've found the answer myself. I've figured out that the problem was the file javax.annotation.processing.Processor in META-INF/services/ with the configuration of the annotation processor's class. In order to fix the problem I had to add the following to the pom.xml configuration of my processor project:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<compilerArgument>
-proc:none
</compilerArgument>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
This let Maven build the classes into the actual jar and fixed the problem. I don't know if this is a bug or not but it surely looks strange to me. Thank you everybody for the help!

The easiest way is to register the annotation processor in the META-INF/services directory of the revolver-annotation-processor artifact. No Maven compiler configuration is needed.
Check if it's already registered, if not, register it yourself if you control the source code.
https://docs.oracle.com/javase/8/docs/api/java/util/ServiceLoader.html
If you control the source code I also recommend to package the processor in the same artifact as the annotations. Like this, whenever you're using one of the annotations, the annotation processor is also picked-up by the compiler.

The accepted answer here works by disabling all annotation processing, which may not be suitable if other annotation processors need to run during the compilation. Instead, the SPI configuration file listing the newly compiled annotation processor can be added in a post-processing step. I added a directory src/main/post-resources to my project and this plugin configuration:
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.3.0</version>
<executions>
<execution>
<id>annotation-processor-spi</id>
<phase>process-classes</phase>
<goals>
<goal>copy-resources</goal>
</goals>
<configuration>
<outputDirectory>${project.build.outputDirectory}</outputDirectory>
<resources>
<resource>
<directory>src/main/post-resources</directory>
</resource>
</resources>
</configuration>
</execution>
</executions>
</plugin>

Custom second packaging artifact from single pom.xml, like jar and test-jar?

I have a group of projects that have (a) generated beans, and (b) code to work with those beans. I'd like each such project to create two different artifacts: a regular jar artifact that contains all classes, and a custom beans artifact that contains only the generated types.
I put together a quick plugin that creates a second beans artifact using artifact attachments and the "beans" classifier, but it doesn't work well in m2e. For this reason, I think creating a custom packaging type (e.g., "test-jar") is The Right Thing.
To be totally clear about what I'm imagining, this pom would works today and creates two different artifacts with two different packaging types:
<project>
<groupId>${groupId}</groupId>
<artifactId>${artifactId}</artifactId>
<version>${version}</version>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>test-jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
which you could import with either of the following:
<dependency>
<groupId>${groupId}</groupId>
<artifactId>${artifactId}</artifactId>
<version>${version}</version>
<!-- <type>jar</type> -->
</dependency>
<dependency>
<groupId>${groupId}</groupId>
<artifactId>${artifactId}</artifactId>
<version>${version}</version>
<type>test-jar</type>
</dependency>
I'd like to create a plugin that will let me use (for example) beans instead of test-jar to create a similar "paired" artifact.
I've poked around in the maven source code, and you can create custom types. However, "test-jar" seems to be "baked in" to maven, so I can't tell if it has some special features and I can't duplicate this behavior with my own plugin.
Of course, if there's another way to handle this kind of behavior without custom types that m2e understands -- for example, but getting m2e to understand my classifier, although that seems hard -- I'm all ears! :)
How can I make a similar paired packaging type? I've seen this answer regarding how to create custom types, but it only seems to create one artifact from a pom with the given custom packaging type.

OK, figured out how to get a custom type working with an additional artifact from the same POM.
You do use attached artifacts to generate the additional artifact. For my example, I used this call in my goal in my plugin (after I was done building my JAR file):
#Mojo(name="goal-name", defaultPhase=LifecyclePhase.PACKAGE)
public class MyMojo
extends AbstractMojo
{
#Component
private MavenProject project;
#Component
private MavenProjectHelper projectHelper;
#Component(role=Archiver.class, hint="jar")
private JarArchiver archiver;
public void execute() throws MojoExecutionException {
// Do work...
// Create JAR file...
File jarFile=createJarFile(archiver);
projectHelper.attachArtifact(project, "beans-jar", jarFile);
}
}
Note that I specified my custom type beans-jar, and no classifier.
Next, I dropped a components file into my plugin at src/main/resources/plexus/components.xml:
<component-set>
<components>
<component>
<role>org.apache.maven.artifact.handler.ArtifactHandler</role>
<role-hint>beans-jar</role-hint>
<implementation>org.apache.maven.artifact.handler.DefaultArtifactHandler</implementation>
<configuration>
<classifier>beans</classifier>
<extension>jar</extension>
<type>beans-jar</type>
<packaging>jar</packaging>
<language>java</language>
<addedToClasspath>true</addedToClasspath>
</configuration>
</component>
</components>
</component-set>
Here, I specify my custom type beans-jar and a classifier, which appears to be used to name the new attribute in the repository.
This file was based on artifact-handlers.xml from the maven-core project in the main maven repository. At the moment, that file is located here. (I found this file by grepping for test-jar in all .xml files in the maven repository.)
To import that dependency, you use:
<dependency>
<groupId>${groupId}</groupId>
<artifactId>${artifactId}</artifactId>
<type>beans-jar</type>
</dependency>
To import the dependency, you don't need to include the custom plugin.

I would suggest to try a simpler way like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<executions>
<execution>
<id>second-jar</id>
<goals>
<goal>jar</goal>
</goals>
<configuration>
<classifier>second</classifier>
<includes>
<include>**/service/*</include>
</includes>
</configuration>
</execution>
</executions>
</plugin>
Via the <include> you can defined which classes would be packaged into the supplemental jar file.

How to resolve cyclic dependency in supplementary Maven sub-module?

There is a multi-module Maven-3 project, where one of sub-modules is used as <dependency> in all other modules. At the same time, all sub-modules inherit from parent module. Such a structure leads to cyclic dependency. How can I resolve it?
Project structure is rather typical:
/foo
/foo-testkit
/foo-core
This is parent foo/pom.xml:
[...]
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
<configuration>
<configLocation>checkstyle/checks.xml</configLocation>
</configuration>
<dependencies>
<dependency>
<groupId>${project.groupId}</groupId>
<artifactId>foo-testkit</artifactId>
<version>${project.version}</version>
</dependency>
</dependencies>
<executions>
<execution>
<phase>prepare-package</phase>
<goals>
<goal>check</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
[...]
In parent foo/pom.xml I specify how and when checkstyle plugin has to be executed in every sub-module. But I don't need checkstyle to be executed in foo-testkit, which is a sub-module inheriting from foo, but is at the same time a dependency..

One way is to disable the checkstyle plugin for module foo-testkit by adding the below to foo-testkit's pom.xml file.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
If that is not to your liking, another way is to move the checkstyle plugin configuration from build/plugins to build/pluginManagment/plugins in the parent pom.xml file. Then in each module you want checkstyle executed, add this to the build/plugins section of each module's pom.xml file:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
</plugin>
This invokes the plugin for that module and the configuration specified in the parent pom.xml under the pluginManagement section will be applied. You can verify that is working correctly by running mvn help:effective-pom on that module.

I agree with Tim Clemons's answer, but there is also an alternative, make your project nested.
root
/ \
common sub-root
/ | \
sub1 sub2 sub3
Define the dependency to common in the sub-root pom. I'm not saying this is a best practice, but it is a solution to your problem.

So I take it the parent pom is referencing one of the submodules as a dependency? I would suggest if you have any build logic going on in the parent module you push it down into a new submodule. The parent should limit itself to specifying the <modules>, <pluginManagement>, and <dependencyManagement> sections. All other work should be farmed out to submodules.
See the following for more advice on organizing multi-module projects:
http://www.sonatype.com/books/mvnref-book/reference/pom-relationships-sect-pom-best-practice.html

If you don't actually need it in foo (only in its sub modules), you can solve the cyclic issue by moving the plugin definition from the build segment to a pluginManagement segment in foo/pom.xml.