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https://issues.apache.org/jira/browse/MNG-6772?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16975144#comment-16975144
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Robert Scholte commented on MNG-6772:
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My focus is on something else right now.
And fixing things in Maven Dependency Resolution has a history. Did you notice
the missing Maven 3.4.0? It was an attempt to improve it, but it complete
changed Maven behavior, breaking a huge amount of projects.
So changing something that seems to work for quite a while must be done with
great care.
To me overriding 'central' from within the project is a 'codesmell', the
preferred way is the settings.xml. I have worked for huge companies and i I
don't understand the issue with distributing these settings.
All together I won't pick this up soon, maybe somebody else will.
> 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
> Priority: Major
> 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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