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https://issues.apache.org/jira/browse/SPARK-32385?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17178588#comment-17178588
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Sean R. Owen commented on SPARK-32385:
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This requires us fixing every version of every transitive dependency. How does
that get updated as the transitive dependency graph changes? this exchanges one
problem for another I think. That is, we are definitely not trying to fix
dependency versions except where necessary.
Gradle isn't something that this project supports, but, wouldn't this be a much
bigger general problem if its resolution rules are different from Maven? that
is, surely gradle can emulate Maven if necessary. (We have the same issue with
SBT, which is why it is not used for builds or publishing artifacts)
> Publish a "bill of materials" (BOM) descriptor for Spark with correct
> versions of various dependencies
> ------------------------------------------------------------------------------------------------------
>
> Key: SPARK-32385
> URL: https://issues.apache.org/jira/browse/SPARK-32385
> Project: Spark
> Issue Type: Improvement
> Components: Build
> Affects Versions: 3.1.0
> Reporter: Vladimir Matveev
> Priority: Major
>
> Spark has a lot of dependencies, many of them very common (e.g. Guava,
> Jackson). Also, versions of these dependencies are not updated as frequently
> as they are released upstream, which is totally understandable and natural,
> but which also means that often Spark has a dependency on a lower version of
> a library, which is incompatible with a higher, more recent version of the
> same library. This incompatibility can manifest in different ways, e.g as
> classpath errors or runtime check errors (like with Jackson), in certain
> cases.
>
> Spark does attempt to "fix" versions of its dependencies by declaring them
> explicitly in its {{pom.xml}} file. However, this approach, being somewhat
> workable if the Spark-using project itself uses Maven, breaks down if another
> build system is used, like Gradle. The reason is that Maven uses an
> unconventional "nearest first" version conflict resolution strategy, while
> many other tools like Gradle use the "highest first" strategy which resolves
> the highest possible version number inside the entire graph of dependencies.
> This means that other dependencies of the project can pull a higher version
> of some dependency, which is incompatible with Spark.
>
> One example would be an explicit or a transitive dependency on a higher
> version of Jackson in the project. Spark itself depends on several modules of
> Jackson; if only one of them gets a higher version, and others remain on the
> lower version, this will result in runtime exceptions due to an internal
> version check in Jackson.
>
> A widely used solution for this kind of version issues is publishing of a
> "bill of materials" descriptor (see here:
> [https://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html]
> and here:
> [https://docs.gradle.org/current/userguide/platforms.html#sub:bom_import]).
> This descriptor would contain all versions of all dependencies of Spark; then
> downstream projects will be able to use their build system's support for BOMs
> to enforce version constraints required for Spark to function correctly.
>
> One example of successful implementation of the BOM-based approach is Spring:
> [https://www.baeldung.com/spring-maven-bom#spring-bom]. For different Spring
> projects, e.g. Spring Boot, there are BOM descriptors published which can be
> used in downstream projects to fix the versions of Spring components and
> their dependencies, significantly reducing confusion around proper version
> numbers.
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