Multiple resolvers having different access mechanism configured with same name 'sbt-plugin-releases'

Question

In the Spark root directory, when I launch "sbt", a message will show up:

Multiple resolvers having different access mechanism configured with same name 'sbt-plugin-releases'.

What does this message imply? and what should I do to fix it?

Answer 1

Like Viktor Hedefalk already mentioned in his comment, the warning is not related to Apache Spark but to the configuration of sbt.

Root cause

Resolvers with the same name but a different URL or access method (http, https...) are defined in your build.sbt or in your sbt configuration.

Consequences

sbt cannot guarantee that the resolver used for that name is the one you expect.

Fix

Check your build.sbt for duplicate resolvers. Both resolvers += and publishTo := lines matter!

Also, check if ~/.sbt/repositories exists and what's in there.

In my case, I was using the flag -Dsbt.repository.config and the configuration file was conflicting with my build.sbt.

References

https://www.scala-sbt.org/0.13/sxr/sbt/Defaults.scala.html#sbt.Classpaths.warnResolversConflict

https://gitter.im/sbt/sbt/archives/2015/06/26