[ZEPPELIN-1407] Fix Scala 2.11 build

[lresende]

What is this PR for?

Avoid activating the Scala 2.10 profile when building for Scala 2.11

What type of PR is it?

[Bug Fix]

What is the Jira issue?

• (https://issues.apache.org/jira/browse/ZEPPELIN-1407)[https://issues.apache.org/jira/browse/ZEPPELIN-1407]

How should this be tested?

Perform Scala 2.10 and 2.11 builds starting from a maven repository that does not have org.apache.zeppelin artifacts.

[lresende]

@bzz @Leemoonsoo Please review, this is more like a hotfix for the build.

[lresende]

This should go for both master and 0.6x release.

[felixcheung]

build failed I think because of

[ERROR] Failed to execute goal on project zeppelin-spark-dependencies_2.10: Could not resolve dependencies for project org.apache.zeppelin:zeppelin-spark-dependencies_2.10:jar:0.7.0-SNAPSHOT: The following artifacts could not be resolved: org.apache.spark:spark-core_2.11:jar:1.1.1, org.apache.spark:spark-repl_2.11:jar:1.1.1, org.apache.spark:spark-sql_2.11:jar:1.1.1, org.apache.spark:spark-hive_2.11:jar:1.1.1, org.apache.spark:spark-streaming_2.11:jar:1.1.1, org.apache.spark:spark-catalyst_2.11:jar:1.1.1, org.spark-project.akka:akka-actor_2.11:jar:2.2.3-shaded-protobuf, org.spark-project.akka:akka-remote_2.11:jar:2.2.3-shaded-protobuf, org.spark-project.akka:akka-slf4j_2.11:jar:2.2.3-shaded-protobuf, org.spark-project.akka:akka-testkit_2.11:jar:2.2.3-shaded-protobuf, org.spark-project.akka:akka-zeromq_2.11:jar:2.2.3-shaded-protobuf: Could not find artifact org.apache.spark:spark-core_2.11:jar:1.1.1 in central (http://repo.maven.apache.org/maven2) -> [Help 1]

[lresende]

@bzz Sorry, I had put the profiles activation as if scala 2.11 was the default, have fixed it now.
three builds still failing with timeout, I will try to force new builds

[lresende]

@bzz the build errors are related to RAT issues

No output has been received in the last 10 minutes, this potentially indicates a stalled build or something wrong with the build itself.

The build has been terminated

[felixcheung]

CI green, any more comments?

[lresende]

@felixcheung @Leemoonsoo @bzz Any more comments here ? Should we merge this to 0.6 branch and master, as it's kind blocking to 2.11

[felixcheung]

Done. master and branch-0.6 - thanks!

[Leemoonsoo]

I'm sorry my comment is bit late. code is already been merged.

But let my write it for the records

Because of all our documents and scripts uses -Pscala-2.xx instead of -Dscala-2.xx. And with -Pscala-2.xx we don't have any problem.

Build instruction
https://github.com/apache/zeppelin#-pscala-version-optional

travis ci script
https://github.com/apache/zeppelin/blob/master/.travis.yml#L43

release script
https://github.com/apache/zeppelin/blob/master/dev/create_release.sh#L106

If we want to use -D instead of -P to activate profile, that's different story.
I think using -D is actually more flexible than -P in maven, but while all other profiles are activated by -P, i'm not sure only activating scala profile by -D can be helpful and beneficial.

[lresende]

@Leemoonsoo The issue wasn't about -P versus -D, but that the Scala 2.10 was with activation true by default, so even when you did only -Pscala2.11 the Scala 2.10 profile was being activated.

[lresende]

BTW, the properties on the profile activation, only enables the "default" to be activated by default, so mvn clean install will not have properties defined, so will start Scala 2.10...

[Leemoonsoo]

@lresende You can see followings from http://maven.apache.org/guides/introduction/introduction-to-profiles.html.

All profiles that are active by default are automatically deactivated when a profile in the POM is activated on the command line or through its activation config.

So once -Pscala-2.11 is defined, scala-2.10 should be automatically deactivated.

[lresende]

But unfortunately this wasn't what maven was enforcing, and Scala 2.11 build was failing when -PScala2.11 was being used, and when invoking dependency:tree with -Pscala2.11 there were few dependencies that were being resolved to _2.10 version of the dependency and thus causing the build failure. This approach seems to not rely on that maven feature and make the build work on both scenarios.

[Leemoonsoo]

@lresende In the issue description, your build command used -Dscala-2.11 when you get those errors.

I could reproduce the error when i use -Dscala-2.11, but if i use -Pscala-2.11 i couldn't reproduce the problem.

[felixcheung]

It looks like -D is in fact setting property and this change is adding such a check for the property?

[minahlee]

As moon mentioned, if you use build instruction in https://github.com/apache/zeppelin#example it doesn't bring any issue.
One of the reason I changed activation rule in #1251 was that using -D won't be scalable for scala-2.12 support in the future.
@lresende if you are not strongly against to build with -P and if you can confirm that there is no issue to build using -Pscala-2.11 not -Dscala-2.11 in c88010f, I would like to revert this change.

[lresende]

I have verified that with that by reverting my changes -PScala2.10/Scala2.11 have the proper behavior and my original issue was that indeed my build alias had -D for the profile activation. Sorry for the confusion, please go ahead and revert this change.

[minahlee]

@lresende thank you for verification. I am reverting this PR then.