Flattened pom for core project invalid

[maybeec]

Expected behavior

As an architect, I want package all modules of my software so that I can individually build and test each of the maven modules separately.

Actual behavior

Having the core maven module deployed, a dependent software module build like the batch module states, that the deployed pom.xml of the core module is not valid as of dependency version not set for

        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-tomcat</artifactId>
        </dependency>

Steps to reproduce (bug) / Use Case of feature request (enhancement)

1. create new project by archetype
2. run mvn clean install on the entire multi-module project
3. go to batch module folder
4. run mvn clean test

Related/Dependent Issues

mojohaus/flatten-maven-plugin#70

[hohwille]

@maybeec Thanks for the feedback and also the link to the flatten issue you found.
Seems I do have some homework here. That is the drawback when you are starting many OSS projects trying to make the world better, you earn lots of maintenance effort. As I began flatten-maven-plugin more as a kind of PoC to show the maven community how a better maven should look like in the future, I might need to find another maintainer for this on the long run. However, for this issue I will try my best to find a fix and ship a new version. However, I can not primise this before end of November.

[hohwille]

However, if I read your report carefully I come to the impression that we are creating an entirely invalid POM here. That does not only mean that the local build of the batch module is somehow problematic but the entire "release" of that module is kind of invalid and if some other project would import that dependency it would also not work.
I can not say how much of a blocker that is, but it sounds like a rather bad bug and not just a nice to have issue.

[hohwille]

Via OSSRH SNAPSHOT deployment we can at least verify our POMs of devon4j now:
https://oss.sonatype.org/content/repositories/snapshots/com/devonfw/java/modules/devon4j-basic/3.3.0-SNAPSHOT/devon4j-basic-3.3.0-20200306.092248-3.pom

[hohwille]

Can someone shed some light into this issue?
I created a devon4j project from the latest archetype from develop branch.
There is not flattening happening at all. Did we disable flatten plugin in archetype already as a quickfix for this issue long time ago?
In the toplevel POM of the archetype flatten plugin is configured in pluginManagement but the plugin itself is not used in build->plugins so the entire issue is invalid.
Can someone confirm before I close this issue?

[hohwille]

Even the archetype POM from the first commit of devon4j did not activate flatten plugin:
https://github.com/devonfw/devon4j/blob/9b8f9461997bb5d8048a9fec42bec3625652eec3/templates/server/src/main/resources/archetype-resources/pom.xml

This issue does not make any sense to me. I will have to close as invalid.
@maybeec if you have anything to shed some light into this and indicate what I might be missing, please go ahead.

[hohwille]

Step 1:

devon java create com.example.mydemo -Dbatch=batch
Trying to determine the latest available version from https://repo.maven.apache.org/maven2/com/devonfw/java/templates/devon4j-template-server/maven-metadata.xml
Running: /Users/hohwille/projects/test/software/maven/bin/mvn archetype:generate -DarchetypeGroupId=com.devonfw.java.templates -DarchetypeArtifactId=devon4j-template-server -DinteractiveMode=false -Dbatch=batch -Dpackage=com.example.mydemo -DartifactId=mydemo -DgroupId=com.example -Dversion=1.0.0-SNAPSHOT -DarchetypeVersion=3.2.1

Step 2:

mvn clean install
...
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  27.427 s
[INFO] Finished at: 2020-04-02T20:54:33+02:00
[INFO] ------------------------------------------------------------------------

Step 3:

cd batch

Step 4:

mvn clean test
...
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  4.074 s
[INFO] Finished at: 2020-04-02T20:56:31+02:00
[INFO] ------------------------------------------------------------------------```

[maybeec]

The problem should automatically occur if "embedded" profile is enabled, which is enabled by default: https://github.com/devonfw/devon4j/blob/master/templates/server/src/main/resources/archetype-resources/core/pom.xml#L233

Anyhow, the issue possibly also is caused by a slightly different setup in my project as I added the test resources to the batch run as well to not have redundant test properties etc to be configured:

<plugin>
	<groupId>org.apache.maven.plugins</groupId>
	<artifactId>maven-jar-plugin</artifactId>
	<executions>
		<execution>
			<goals>
				<goal>test-jar</goal>
			</goals>
		</execution>
	</executions>
</plugin>

to core and include

<dependency>
	<groupId>${project.groupId}</groupId>
	<artifactId>?-core</artifactId>
	<version>${project.version}</version>
	<type>test-jar</type>
	<scope>test</scope>
</dependency>

to batch pom.xml. At least, this is the change we did.