Maven jobs can be now executed with its own private local Maven repository for better isolation.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@10023 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/maven/MavenBuild.java

@@ -420,7 +420,12 @@ public class MavenBuild extends AbstractBuild<MavenModule,MavenBuild> {
 
             ArgumentListBuilder margs = new ArgumentListBuilder();
             margs.add("-N").add("-B");
-            margs.add("-f",getParent().getModuleRoot().child("pom.xml").getRemote());
+            MavenModuleSet mms = project.getParent();
+            if(mms.usesPrivateRepository())
+                // use the per-project repository. should it be per-module? But that would cost too much in terms of disk
+                // the workspace must be on this node, so getRemote() is safe.
+                margs.add("-D").add("maven.repo.local="+mms.getWorkspace().child(".repository").getRemote());
+            margs.add("-f",getProject().getModuleRoot().child("pom.xml").getRemote());
             margs.addTokenized(getProject().getGoals());
 
             Map<String,String> systemProps = new HashMap<String, String>(envVars);

core/src/main/java/hudson/maven/MavenModuleSet.java

@@ -81,6 +81,18 @@ public final class MavenModuleSet extends AbstractMavenProject<MavenModuleSet,Ma
      */
     private boolean aggregatorStyleBuild = true;
 
+    /**
+     * If true, the build will use its own local Maven repository
+     * via "-Dmaven.repo.local=...".
+     * <p>
+     * This would consume additional disk space, but provides isolation with other builds on the same machine,
+     * such as mixing SNAPSHOTS. Maven also doesn't try to coordinate the concurrent access to Maven repositories
+     * from multiple Maven process, so this helps there too.
+     *
+     * @sine 1.223
+     */
+    private boolean usePrivateRepository = false;
+
     /**
      * Reporters configured at {@link MavenModuleSet} level. Applies to all {@link MavenModule} builds.
      */
@@ -211,6 +223,10 @@ public final class MavenModuleSet extends AbstractMavenProject<MavenModuleSet,Ma
         return aggregatorStyleBuild;
     }
 
+    public boolean usesPrivateRepository() {
+        return usePrivateRepository;
+    }
+
     /**
      * List of active {@link MavenReporter}s that should be applied to all module builds.
      */
@@ -500,7 +516,8 @@ public final class MavenModuleSet extends AbstractMavenProject<MavenModuleSet,Ma
         goals = Util.fixEmpty(req.getParameter("goals").trim());
         mavenOpts = Util.fixEmpty(req.getParameter("mavenOpts").trim());
         mavenName = req.getParameter("maven_version");
-        aggregatorStyleBuild = req.getParameter("maven.perModuleBuild")==null;
+        aggregatorStyleBuild = !req.hasParameter("maven.perModuleBuild");
+        usePrivateRepository = req.hasParameter("maven.usePrivateRepository");
 
         JSONObject json = StructuredForm.get(req);
         reporters.rebuild(req,json,MavenReporters.getConfigurableList(),"reporter");

core/src/main/java/hudson/maven/MavenModuleSetBuild.java

@@ -318,6 +318,8 @@ public final class MavenModuleSetBuild extends AbstractBuild<MavenModuleSet,Mave
 
                         ArgumentListBuilder margs = new ArgumentListBuilder();
                         margs.add("-B").add("-f", pom.getRemote());
+                        if(project.usesPrivateRepository())
+                            margs.add("-D").add("maven.repo.local="+project.getWorkspace().child(".repository"));
                         margs.addTokenized(project.getGoals());
 
                         Builder builder = new Builder(slistener, proxies, project.sortedActiveModules, margs.toList(), envVars);

core/src/main/resources/hudson/maven/MavenModuleSet/configure-entries.jelly

@@ -40,6 +40,8 @@
       </f:entry>
       <f:optionalBlock name="maven.perModuleBuild" title="${%Build modules in parallel}" help="/help/maven/aggregator.html"
         checked="${!it.aggregatorStyleBuild}" />
+      <f:optionalBlock name="maven.usePrivateRepository" title="${%Use private maven repository}" help="/help/maven/private-repository.html"
+        checked="${it.usesPrivateRepository()}" />
     </f:advanced>
   </f:section>
 

war/resources/help/maven/private-repository.html

+<div>
+  Normally, Hudson uses the local Maven repository as determined by Maven &mdash; the exact process
+  seems to be undocumented, but it's <tt>~/.m2/repository</tt> and can be overridden by
+  &lt;localRepository> in <tt>~/.m2/settings.xml</tt> (see <a  href="http://maven.apache.org/settings.html">the reference</a> for more details.)
+
+  <p>
+  This normally means that all the jobs that are executed on the same node shares a single Maven repository.
+  The upside of this is that you can save the disk space, but the downside of this is that sometimes those
+  builds could interfere with each other. For example, you might end up having builds incorrectly succeed,
+  just because your have all the dependencies in your local repository, despite that fact that none of the
+  repositories in POM might have them.
+
+  <p>
+  There are also some reported problems regarding having concurrent Maven processes trying to use the same local
+  repository.
+
+
+  <p>
+  When this option is checked, Hudson will tell Maven to use <tt>$WORKSPACE/.repository</tt> as the local Maven repository.
+  This means each job will get its own isolated Maven repository just for itself. It fixes the above problems,
+  at the expense of additional disk space consumption.
+
+  <p>
+  When using this option, consider setting up a Maven artifact manager so that you don't have to hit
+  remote Maven repositories too often.
+</div>
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