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https://issues.apache.org/jira/browse/MNG-6772?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17237467#comment-17237467
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Eddie Wiegers commented on MNG-6772:
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[~michael-o], I know you've mentioned that there are plans to move the Maven
Central repository reference out of the Super POM and into the default
settings.xml file, as well as potentially change some other behavior around the
way repository definitions and inheritance work. I'm perfectly fine with that
and don't believe this JIRA does anything to work against that design.
I would like to remind everyone that the changes made in this JIRA in no way
fundamentally alter the way repository inheritance works. Maven has supported
the current repository inheritance behavior for a long time, and this JIRA
simply fixes a small edge case to have it behave consistently.
Even if my use case is "broken" or doesn't align with Maven best practices
(current or future), I don't see the point of reverting a bug fix with the
current behavior when the overall behavior still remains (and works for the
other 99% of cases).
> Super POM overwrites remapped central repository in nested import POMs
> ----------------------------------------------------------------------
>
> Key: MNG-6772
> URL: https://issues.apache.org/jira/browse/MNG-6772
> Project: Maven
> Issue Type: Bug
> Components: Artifacts and Repositories, POM
> Affects Versions: 3.6.2
> Reporter: Eddie Wiegers
> Assignee: Sylwester Lachiewicz
> Priority: Major
> Fix For: 3.7.0
>
> Time Spent: 20m
> Remaining Estimate: 0h
>
> My projects define a repository with {{<id>central</id>,}} which is meant to
> specifically override the entry in the Super POM. This is specifically what
> [JFrog Artifactory
> recommends|https://www.jfrog.com/confluence/display/RTF/Maven+Repository#MavenRepository-ManuallyOverridingtheBuilt-inRepositories]
> doing, and seems valid in situations where the _real_ Maven Central may be
> unreachable.
>
> The override takes precedence almost all of the time. However, there is at
> least one scenario where this is not the case, and that is when importing a
> POM that in turn imports another POM.
>
> Digging into the code, it appears the reason this happens is because the
> {{DefaultModelBuilder}} overwrites repositories after interpolation is
> complete:
> [https://github.com/apache/maven/blob/53f04f03e3e58c75dcc791d557758357a6ec7983/maven-model-builder/src/main/java/org/apache/maven/model/building/DefaultModelBuilder.java#L411]
>
> From what I can tell, this is done with the intention of overwriting
> repositories that were added to the local resolver prior to interpolation
> with the interpolated version. Due to the way the {{DefaultModelResolver}}
> works, an unintended side effect is that the {{central}} repository from the
> Super POM is added once after each interpolation. The first time the
> repository is added, it is added to the {{repositoryIds}} but doesn't
> actually remove the original repository. The second time it is added is when
> the original repository will be replaced. Currently, the repositoryIds are
> preserved in the {{ModelResolver}} when resolving import POMs, leading to the
> behavior I am seeing where the second nested import POM ends up being where
> the failure occurs.
>
> I am planning on submitting a PR to clone the {{ModelResolver}} in a way that
> resets the repositoryIds prior to import POMs being resolved, since they are
> separate artifact builds. That seems like the most consistent fix to me that
> covers cases outside of the the Super POM's {{central}} definition.
>
> *Workarounds*:
> The current workaround is to use a repository ID other than {{central}} for
> my Artifactory repository, which isn't ideal since it leaves the potential
> for long timeouts to occur on the real {{central}} when an artifact can't be
> resolved from my Artifactory repository.
>
> Mirrors are not an ideal workaround since getting them in place on all
> possible build environments isn't trivial.
>
> When looking at the code I noticed
> {{RepositorySystemSession#isIgnoreArtifactDescriptorRepositories()}} being
> checked in various places, which seems like it would also act as a potential
> workaround, but I don't see a way to enable this value via MavenCLI or
> properties of any kind. It seems like this value aligns well with what
> Artifactory is already trying to enforce, so it would make sense to enable
> this in projects that intend to exclusively use Artifactory. Is there a
> supported way to set this value outside of constructing a Maven build in code?
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