[SPARK-8819] Fix build for maven 3.3.x

This is a workaround for MSHADE-148, which leads to an infinite loop when building Spark with maven 3.3.x. This was originally caused by #6441, which added a bunch of test dependencies on the spark-core test module. Recently, it was revealed by #7193.

This patch adds a `-Prelease` profile. If present, it will set `createDependencyReducedPom` to true. The consequences are:
- If you are releasing Spark with this profile, you are fine as long as you use maven 3.2.x or before.
- If you are releasing Spark without this profile, you will run into SPARK-8781.
- If you are not releasing Spark but you are using this profile, you may run into SPARK-8819.
- If you are not releasing Spark and you did not include this profile, you are fine.

This is all documented in `pom.xml` and tested locally with both versions of maven.

Author: Andrew Or <andrew@databricks.com>

Closes #7219 from andrewor14/fix-maven-build and squashes the following commits:

1d37e87 [Andrew Or] Merge branch 'master' of github.com:apache/spark into fix-maven-build
3574ae4 [Andrew Or] Review comments
f39199c [Andrew Or] Create a -Prelease profile that flags `createDependencyReducedPom`

1 files changed, 24 insertions, 0 deletions

diff --git a/pom.xml b/pom.xml
index ffa96128a3..fbcc915276 100644
--- a/pom.xml
+++ b/pom.xml
@@ -161,6 +161,8 @@
     <fasterxml.jackson.version>2.4.4</fasterxml.jackson.version>
     <snappy.version>1.1.1.7</snappy.version>
     <netlib.java.version>1.1.2</netlib.java.version>
+    <!-- For maven shade plugin (see SPARK-8819) -->
+    <create.dependency.reduced.pom>false</create.dependency.reduced.pom>
 
     <test.java.home>${java.home}</test.java.home>
 
@@ -1440,6 +1442,8 @@
         <version>2.3</version>
         <configuration>
           <shadedArtifactAttached>false</shadedArtifactAttached>
+          <!-- Work around MSHADE-148. See SPARK-8819. -->
+          <createDependencyReducedPom>${create.dependency.reduced.pom}</createDependencyReducedPom>
           <artifactSet>
             <includes>
               <!-- At a minimum we must include this to force effective pom generation -->
@@ -1826,6 +1830,26 @@
       </properties>
     </profile>
 
+    <profile>
+      <!--
+          Use this profile only for making Spark releases. Note that due to SPARK-8819,
+          you must use maven version 3.2.x or before to avoid running into MSHADE-148.
+      -->
+      <id>release-profile</id>
+      <properties>
+        <!--
+            The maven shade plugin has a bug where enabling the `createDependencyReducedPom`
+            property causes maven to go into an infinite loop (MSHADE-148). This is only an
+            issue for the Spark build if the maven version is 3.3.x or newer (SPARK-8819).
+
+            However, since disabling this property has the side effect of not resolving
+            variables in the released pom files (SPARK-8781), we need to enable this during
+            releases.
+        -->
+        <create.dependency.reduced.pom>true</create.dependency.reduced.pom>
+      </properties>
+    </profile>
+
     <!--
       These empty profiles are available in some sub-modules. Declare them here so that
       maven does not complain when they're provided on the command line for a sub-module