[MNG-6585] Unable to load snapshot extensions from extensions.xml

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Incomplete
• Affects Version/s: 3.3.9, 3.5.4, 3.6.0
• Component/s: Core
• Assignee: Unassigned
• Reporter: Robert Thornton
• Created: 05/Feb/19 17:19
• Updated: 03/Apr/19 20:09
• Resolved: 03/Apr/19 20:09

Description

I'm developing an extension in a continuous build environment and Maven doesn't even attempt to download the extension if the entry in .mvn/extensions.xml has a -SNAPSHOT version. It simply fails with a warning that it could not find the extension without explaining why it didn't try to download it. This means that in order for me to try out the extension, I have either have to build it locally or make a release first. I've been unable to find any documentation that identifies this as an intentional limitation, which leads me to believe it must be a bug.

For example, my extension allows the pom.xml to be written in a Kotlin DSL. Because my pom is named pom.kts instead of pom.xml, my build will fail if it cannot download the extension as defined below:

<?xml version="1.0" encoding="UTF-8"?>
<extensions>
  <extension>
    <groupId>io.takari.polyglot</groupId>
    <artifactId>polyglot-kotlin</artifactId>
    <version>0.3.3-SNAPSHOT</version>
  </extension>
</extensions> 

However, if I change the version to a non-snapshot, Maven does attempt to download the extension:

<?xml version="1.0" encoding="UTF-8"?>
<extensions>
  <extension>
    <groupId>io.takari.polyglot</groupId>
    <artifactId>polyglot-kotlin</artifactId>
    <version>0.3.3.beta01</version>
  </extension>
</extensions> 

It seems to me that Maven should attempt to resolve the extension regardless of whether it is a snapshot or not because my plugin repository in settings.xml has been configured to allow snapshots.