Maven plugin should be able to create a new Quarkus module when there is a root pom.xml file

[agoncal]

Description

This issue is the follows up of a Zulip discusson[1]. Today, if you use the Maven plugin to create a new project (mvn quarkus-maven-plugin:create) and that there is a root pom.xml file, it errors[2]:

Unable to generate the project in a directory that already contains a pom.xml

Instead it should create the project, and add a module into the <modules> section. In some use-cases, you can have a pom.xml at the root of several non-Quarkus modules. And from this root, you want to create several Quarkus modules. Having this feature would allow creating Quarkus modules in existing Maven projects with sub-modules.

[1] https://quarkusio.zulipchat.com/#narrow/stream/187030-users/topic/Forcing.20Maven.20plugin.20to.20create.20with.20existing.20pom.2Exml
[2] https://github.com/quarkusio/quarkus/blob/master/devtools/maven/src/main/java/io/quarkus/maven/CreateProjectMojo.java#L166

[quarkusbot]

/cc @quarkusio/devtools

[ghokun]

Hi, I am working on this issue. Covered most of the parts:

• Check parent poms packaging, continue if it is "pom" or fail if not.
• Add modules section to parent pom or do nothing if it already exist.
• Add parent section to newly created projects pom.
• IT for submodule creation

I only checked existence of pom.xml file so it already assumes you are in a maven project. Should I be worried about gradle side of things ?

[agoncal]

I don't know if the Quarkus team wants both Maven and Gradle to have the same set of functionalities. @quarkusbot added the "area/maven" label, so I suppose it's Maven only ;o)

[maxandersen]

maven and gradle should aim for same set of functionallities - the bot added area/maven because you only mentioned maven in your title ;)

[agoncal]

@maxandersen I thought the bot was a clever bot ;o)

[ghokun]

I will try to make required adjustments to my PR #12916

[aloubyansky]

@ghokun feel free to open a separate PR for Gradle in case that's what you meant. Whatever you prefer. And thanks!