o Enabled request tracing for repository events to provide more context for event spies

git-svn-id: https://svn.apache.org/repos/asf/maven/maven-3/trunk@1074195 13f79535-47bb-0310-9956-ffa450edef68

maven-aether-provider/src/main/java/org/apache/maven/repository/internal/DefaultArtifactDescriptorReader.java

@@ -49,6 +49,7 @@ import org.sonatype.aether.RepositoryEvent.EventType;
 import org.sonatype.aether.RepositoryException;
 import org.sonatype.aether.RepositoryListener;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.artifact.Artifact;
 import org.sonatype.aether.artifact.ArtifactType;
 import org.sonatype.aether.artifact.ArtifactTypeRegistry;
@@ -59,6 +60,7 @@ import org.sonatype.aether.impl.ArtifactResolver;
 import org.sonatype.aether.impl.RemoteRepositoryManager;
 import org.sonatype.aether.impl.VersionResolver;
 import org.sonatype.aether.transfer.ArtifactNotFoundException;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.ArtifactProperties;
 import org.sonatype.aether.util.artifact.DefaultArtifact;
 import org.sonatype.aether.util.artifact.DefaultArtifactType;
@@ -224,6 +226,8 @@ public class DefaultArtifactDescriptorReader
                            ArtifactDescriptorResult result )
         throws ArtifactDescriptorException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( request.getTrace(), request );
+
         Set<String> visited = new LinkedHashSet<String>();
         for ( Artifact artifact = request.getArtifact();; )
         {
@@ -231,6 +235,7 @@ public class DefaultArtifactDescriptorReader
             {
                 VersionRequest versionRequest =
                     new VersionRequest( artifact, request.getRepositories(), request.getRequestContext() );
+                versionRequest.setTrace( trace );
                 VersionResult versionResult = versionResolver.resolveVersion( session, versionRequest );
 
                 artifact = artifact.setVersion( versionResult.getVersion() );
@@ -245,7 +250,7 @@ public class DefaultArtifactDescriptorReader
             {
                 RepositoryException exception =
                     new RepositoryException( "Artifact relocations form a cycle: " + visited );
-                invalidDescriptor( session, artifact, exception );
+                invalidDescriptor( session, trace, artifact, exception );
                 if ( session.isIgnoreInvalidArtifactDescriptor() )
                 {
                     return null;
@@ -265,6 +270,7 @@ public class DefaultArtifactDescriptorReader
             {
                 ArtifactRequest resolveRequest =
                     new ArtifactRequest( pomArtifact, request.getRepositories(), request.getRequestContext() );
+                resolveRequest.setTrace( trace );
                 resolveResult = artifactResolver.resolveArtifact( session, resolveRequest );
                 pomArtifact = resolveResult.getArtifact();
                 result.setRepository( resolveResult.getRepository() );
@@ -273,7 +279,7 @@ public class DefaultArtifactDescriptorReader
             {
                 if ( e.getCause() instanceof ArtifactNotFoundException )
                 {
-                    missingDescriptor( session, artifact, (Exception) e.getCause() );
+                    missingDescriptor( session, trace, artifact, (Exception) e.getCause() );
                     if ( session.isIgnoreMissingArtifactDescriptor() )
                     {
                         return null;
@@ -293,8 +299,9 @@ public class DefaultArtifactDescriptorReader
                 modelRequest.setSystemProperties( toProperties( session.getUserProperties(),
                                                                 session.getSystemProperties() ) );
                 modelRequest.setModelCache( DefaultModelCache.newInstance( session ) );
-                modelRequest.setModelResolver( new DefaultModelResolver( session, request.getRequestContext(),
+                modelRequest.setModelResolver( new DefaultModelResolver( session, trace.newChild( modelRequest ),
-                                                                         artifactResolver, remoteRepositoryManager,
+                                                                         request.getRequestContext(), artifactResolver,
+                                                                         remoteRepositoryManager,
                                                                          request.getRepositories() ) );
                 if ( resolveResult.getRepository() instanceof WorkspaceRepository )
                 {
@@ -317,7 +324,7 @@ public class DefaultArtifactDescriptorReader
                         throw new ArtifactDescriptorException( result );
                     }
                 }
-                invalidDescriptor( session, artifact, e );
+                invalidDescriptor( session, trace, artifact, e );
                 if ( session.isIgnoreInvalidArtifactDescriptor() )
                 {
                     return null;
@@ -435,24 +442,28 @@ public class DefaultArtifactDescriptorReader
         return new RepositoryPolicy( enabled, updates, checksums );
     }
 
-    private void missingDescriptor( RepositorySystemSession session, Artifact artifact, Exception exception )
+    private void missingDescriptor( RepositorySystemSession session, RequestTrace trace, Artifact artifact,
+                                    Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.ARTIFACT_DESCRIPTOR_MISSING, session );
+            DefaultRepositoryEvent event =
+                new DefaultRepositoryEvent( EventType.ARTIFACT_DESCRIPTOR_MISSING, session, trace );
             event.setArtifact( artifact );
             event.setException( exception );
             listener.artifactDescriptorMissing( event );
         }
     }
 
-    private void invalidDescriptor( RepositorySystemSession session, Artifact artifact, Exception exception )
+    private void invalidDescriptor( RepositorySystemSession session, RequestTrace trace, Artifact artifact,
+                                    Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.ARTIFACT_DESCRIPTOR_INVALID, session );
+            DefaultRepositoryEvent event =
+                new DefaultRepositoryEvent( EventType.ARTIFACT_DESCRIPTOR_INVALID, session, trace );
             event.setArtifact( artifact );
             event.setException( exception );
             listener.artifactDescriptorInvalid( event );

maven-aether-provider/src/main/java/org/apache/maven/repository/internal/DefaultModelResolver.java

@@ -32,6 +32,7 @@ import org.apache.maven.model.resolution.InvalidRepositoryException;
 import org.apache.maven.model.resolution.ModelResolver;
 import org.apache.maven.model.resolution.UnresolvableModelException;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.artifact.Artifact;
 import org.sonatype.aether.impl.ArtifactResolver;
 import org.sonatype.aether.impl.RemoteRepositoryManager;
@@ -53,6 +54,8 @@ class DefaultModelResolver
 
     private final RepositorySystemSession session;
 
+    private final RequestTrace trace;
+
     private final String context;
 
     private List<RemoteRepository> repositories;
@@ -63,10 +66,12 @@ class DefaultModelResolver
 
     private final Set<String> repositoryIds;
 
-    public DefaultModelResolver( RepositorySystemSession session, String context, ArtifactResolver resolver,
+    public DefaultModelResolver( RepositorySystemSession session, RequestTrace trace, String context,
-                                 RemoteRepositoryManager remoteRepositoryManager, List<RemoteRepository> repositories )
+                                 ArtifactResolver resolver, RemoteRepositoryManager remoteRepositoryManager,
+                                 List<RemoteRepository> repositories )
     {
         this.session = session;
+        this.trace = trace;
         this.context = context;
         this.resolver = resolver;
         this.remoteRepositoryManager = remoteRepositoryManager;
@@ -77,6 +82,7 @@ class DefaultModelResolver
     private DefaultModelResolver( DefaultModelResolver original )
     {
         this.session = original.session;
+        this.trace = original.trace;
         this.context = original.context;
         this.resolver = original.resolver;
         this.remoteRepositoryManager = original.remoteRepositoryManager;
@@ -112,6 +118,7 @@ class DefaultModelResolver
         try
         {
             ArtifactRequest request = new ArtifactRequest( pomArtifact, repositories, context );
+            request.setTrace( trace );
             pomArtifact = resolver.resolveArtifact( session, request ).getArtifact();
         }
         catch ( ArtifactResolutionException e )

maven-aether-provider/src/main/java/org/apache/maven/repository/internal/DefaultVersionRangeResolver.java

@@ -34,6 +34,9 @@ import org.codehaus.plexus.util.IOUtil;
 import org.sonatype.aether.RepositoryEvent.EventType;
 import org.sonatype.aether.RepositoryListener;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
+import org.sonatype.aether.SyncContext;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.listener.DefaultRepositoryEvent;
 import org.sonatype.aether.util.metadata.DefaultMetadata;
 import org.sonatype.aether.util.version.GenericVersionScheme;
@@ -42,6 +45,7 @@ import org.sonatype.aether.version.Version;
 import org.sonatype.aether.version.VersionConstraint;
 import org.sonatype.aether.version.VersionScheme;
 import org.sonatype.aether.impl.MetadataResolver;
+import org.sonatype.aether.impl.SyncContextFactory;
 import org.sonatype.aether.impl.VersionRangeResolver;
 import org.sonatype.aether.metadata.Metadata;
 import org.sonatype.aether.repository.ArtifactRepository;
@@ -67,16 +71,21 @@ public class DefaultVersionRangeResolver
 
     private static final String MAVEN_METADATA_XML = "maven-metadata.xml";
 
+    @SuppressWarnings( "unused" )
     @Requirement
     private Logger logger = NullLogger.INSTANCE;
 
     @Requirement
     private MetadataResolver metadataResolver;
 
+    @Requirement
+    private SyncContextFactory syncContextFactory;
+
     public void initService( ServiceLocator locator )
     {
         setLogger( locator.getService( Logger.class ) );
         setMetadataResolver( locator.getService( MetadataResolver.class ) );
+        setSyncContextFactory( locator.getService( SyncContextFactory.class ) );
     }
 
     public DefaultVersionRangeResolver setLogger( Logger logger )
@@ -95,6 +104,16 @@ public class DefaultVersionRangeResolver
         return this;
     }
 
+    public DefaultVersionRangeResolver setSyncContextFactory( SyncContextFactory syncContextFactory )
+    {
+        if ( syncContextFactory == null )
+        {
+            throw new IllegalArgumentException( "sync context factory has not been specified" );
+        }
+        this.syncContextFactory = syncContextFactory;
+        return this;
+    }
+
     public VersionRangeResult resolveVersionRange( RepositorySystemSession session, VersionRangeRequest request )
         throws VersionRangeResolutionException
     {
@@ -151,6 +170,8 @@ public class DefaultVersionRangeResolver
     private Map<String, ArtifactRepository> getVersions( RepositorySystemSession session, VersionRangeResult result,
                                                          VersionRangeRequest request )
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( request.getTrace(), request );
+
         Map<String, ArtifactRepository> versionIndex = new HashMap<String, ArtifactRepository>();
 
         Metadata metadata =
@@ -165,6 +186,7 @@ public class DefaultVersionRangeResolver
         {
             MetadataRequest metadataRequest = new MetadataRequest( metadata, repository, request.getRequestContext() );
             metadataRequest.setDeleteLocalCopyIfMissing( true );
+            metadataRequest.setTrace( trace );
             metadataRequests.add( metadataRequest );
         }
 
@@ -190,7 +212,7 @@ public class DefaultVersionRangeResolver
                 repository = session.getLocalRepository();
             }
 
-            Versioning versioning = readVersions( session, metadataResult.getMetadata(), repository, result );
+            Versioning versioning = readVersions( session, trace, metadataResult.getMetadata(), repository, result );
             for ( String version : versioning.getVersions() )
             {
                 if ( !versionIndex.containsKey( version ) )
@@ -203,24 +225,39 @@ public class DefaultVersionRangeResolver
         return versionIndex;
     }
 
-    private Versioning readVersions( RepositorySystemSession session, Metadata metadata, ArtifactRepository repository,
+    private Versioning readVersions( RepositorySystemSession session, RequestTrace trace, Metadata metadata,
-                                     VersionRangeResult result )
+                                     ArtifactRepository repository, VersionRangeResult result )
     {
         Versioning versioning = null;
 
         FileInputStream fis = null;
         try
         {
-            if ( metadata != null && metadata.getFile() != null && metadata.getFile().exists() )
+            if ( metadata != null )
+            {
+                SyncContext syncContext = syncContextFactory.newInstance( session, true );
+
+                try
+                {
+                    syncContext.acquire( null, Collections.singleton( metadata ) );
+
+                    if ( metadata.getFile() != null && metadata.getFile().exists() )
                     {
                         fis = new FileInputStream( metadata.getFile() );
-                org.apache.maven.artifact.repository.metadata.Metadata m = new MetadataXpp3Reader().read( fis, false );
+                        org.apache.maven.artifact.repository.metadata.Metadata m =
+                            new MetadataXpp3Reader().read( fis, false );
                         versioning = m.getVersioning();
                     }
                 }
+                finally
+                {
+                    syncContext.release();
+                }
+            }
+        }
         catch ( Exception e )
         {
-            invalidMetadata( session, metadata, repository, e );
+            invalidMetadata( session, trace, metadata, repository, e );
             result.addException( e );
         }
         finally
@@ -231,13 +268,13 @@ public class DefaultVersionRangeResolver
         return ( versioning != null ) ? versioning : new Versioning();
     }
 
-    private void invalidMetadata( RepositorySystemSession session, Metadata metadata, ArtifactRepository repository,
+    private void invalidMetadata( RepositorySystemSession session, RequestTrace trace, Metadata metadata,
-                                  Exception exception )
+                                  ArtifactRepository repository, Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session );
+            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session, trace );
             event.setMetadata( metadata );
             event.setException( exception );
             event.setRepository( repository );

maven-aether-provider/src/main/java/org/apache/maven/repository/internal/DefaultVersionResolver.java

@@ -38,14 +38,18 @@ import org.codehaus.plexus.util.IOUtil;
 import org.codehaus.plexus.util.StringUtils;
 import org.sonatype.aether.ConfigurationProperties;
 import org.sonatype.aether.RepositoryCache;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.RepositoryEvent.EventType;
 import org.sonatype.aether.RepositoryListener;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.SyncContext;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.SubArtifact;
 import org.sonatype.aether.util.listener.DefaultRepositoryEvent;
 import org.sonatype.aether.util.metadata.DefaultMetadata;
 import org.sonatype.aether.artifact.Artifact;
 import org.sonatype.aether.impl.MetadataResolver;
+import org.sonatype.aether.impl.SyncContextFactory;
 import org.sonatype.aether.impl.VersionResolver;
 import org.sonatype.aether.impl.internal.CacheUtils;
 import org.sonatype.aether.metadata.Metadata;
@@ -80,16 +84,21 @@ public class DefaultVersionResolver
 
     private static final String SNAPSHOT = "SNAPSHOT";
 
+    @SuppressWarnings( "unused" )
     @Requirement
     private Logger logger = NullLogger.INSTANCE;
 
     @Requirement
     private MetadataResolver metadataResolver;
 
+    @Requirement
+    private SyncContextFactory syncContextFactory;
+
     public void initService( ServiceLocator locator )
     {
         setLogger( locator.getService( Logger.class ) );
         setMetadataResolver( locator.getService( MetadataResolver.class ) );
+        setSyncContextFactory( locator.getService( SyncContextFactory.class ) );
     }
 
     public DefaultVersionResolver setLogger( Logger logger )
@@ -108,9 +117,21 @@ public class DefaultVersionResolver
         return this;
     }
 
+    public DefaultVersionResolver setSyncContextFactory( SyncContextFactory syncContextFactory )
+    {
+        if ( syncContextFactory == null )
+        {
+            throw new IllegalArgumentException( "sync context factory has not been specified" );
+        }
+        this.syncContextFactory = syncContextFactory;
+        return this;
+    }
+
     public VersionResult resolveVersion( RepositorySystemSession session, VersionRequest request )
         throws VersionResolutionException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( request.getTrace(), request );
+
         Artifact artifact = request.getArtifact();
 
         String version = artifact.getVersion();
@@ -184,6 +205,7 @@ public class DefaultVersionResolver
                     new MetadataRequest( metadata, repository, request.getRequestContext() );
                 metadataRequest.setDeleteLocalCopyIfMissing( true );
                 metadataRequest.setFavorLocalRepository( true );
+                metadataRequest.setTrace( trace );
                 metadataRequests.add( metadataRequest );
             }
 
@@ -201,7 +223,7 @@ public class DefaultVersionResolver
                     repository = session.getLocalRepository();
                 }
 
-                Versioning versioning = readVersions( session, metadataResult.getMetadata(), repository, result );
+                Versioning versioning = readVersions( session, trace, metadataResult.getMetadata(), repository, result );
                 merge( artifact, infos, versioning, repository );
             }
 
@@ -272,24 +294,33 @@ public class DefaultVersionResolver
         return info != null;
     }
 
-    private Versioning readVersions( RepositorySystemSession session, Metadata metadata, ArtifactRepository repository,
+    private Versioning readVersions( RepositorySystemSession session, RequestTrace trace, Metadata metadata,
-                                     VersionResult result )
+                                     ArtifactRepository repository, VersionResult result )
     {
         Versioning versioning = null;
 
         FileInputStream fis = null;
         try
         {
-            if ( metadata != null && metadata.getFile() != null && metadata.getFile().exists() )
+            if ( metadata != null )
+            {
+                SyncContext syncContext = syncContextFactory.newInstance( session, true );
+
+                try
+                {
+                    syncContext.acquire( null, Collections.singleton( metadata ) );
+
+                    if ( metadata.getFile() != null && metadata.getFile().exists() )
                     {
                         fis = new FileInputStream( metadata.getFile() );
-                org.apache.maven.artifact.repository.metadata.Metadata m = new MetadataXpp3Reader().read( fis, false );
+                        org.apache.maven.artifact.repository.metadata.Metadata m =
+                            new MetadataXpp3Reader().read( fis, false );
                         versioning = m.getVersioning();
 
                         /*
-                 * NOTE: Users occasionally misuse the id "local" for remote repos which screws up the metadata of the
+                         * NOTE: Users occasionally misuse the id "local" for remote repos which screws up the metadata
-                 * local repository. This is especially troublesome during snapshot resolution so we try to handle that
+                         * of the local repository. This is especially troublesome during snapshot resolution so we try
-                 * gracefully.
+                         * to handle that gracefully.
                          */
                         if ( versioning != null && repository instanceof LocalRepository )
                         {
@@ -303,14 +334,21 @@ public class DefaultVersionResolver
                                 versioning = repaired;
 
                                 throw new IOException( "Snapshot information corrupted with remote repository data"
-                            + ", please verify that no remote repository uses the id '" + repository.getId() + "'" );
+                                    + ", please verify that no remote repository uses the id '" + repository.getId()
+                                    + "'" );
                             }
                         }
                     }
                 }
+                finally
+                {
+                    syncContext.release();
+                }
+            }
+        }
         catch ( Exception e )
         {
-            invalidMetadata( session, metadata, repository, e );
+            invalidMetadata( session, trace, metadata, repository, e );
             result.addException( e );
         }
         finally
@@ -321,13 +359,13 @@ public class DefaultVersionResolver
         return ( versioning != null ) ? versioning : new Versioning();
     }
 
-    private void invalidMetadata( RepositorySystemSession session, Metadata metadata, ArtifactRepository repository,
+    private void invalidMetadata( RepositorySystemSession session, RequestTrace trace, Metadata metadata,
-                                  Exception exception )
+                                  ArtifactRepository repository, Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session );
+            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session, trace );
             event.setMetadata( metadata );
             event.setException( exception );
             event.setRepository( repository );

maven-compat/src/main/java/org/apache/maven/artifact/deployer/DefaultArtifactDeployer.java

@@ -44,6 +44,7 @@ import org.sonatype.aether.deployment.DeployResult;
 import org.sonatype.aether.deployment.DeploymentException;
 import org.sonatype.aether.metadata.MergeableMetadata;
 import org.sonatype.aether.repository.RemoteRepository;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.SubArtifact;
 
 @Component( role = ArtifactDeployer.class, instantiationStrategy = "per-lookup" )
@@ -83,6 +84,8 @@ public class DefaultArtifactDeployer
 
         DeployRequest request = new DeployRequest();
 
+        request.setTrace( DefaultRequestTrace.newChild( null, legacySupport.getSession().getCurrentProject() ) );
+
         org.sonatype.aether.artifact.Artifact mainArtifact = RepositoryUtils.toArtifact( artifact );
         mainArtifact = mainArtifact.setFile( source );
         request.addArtifact( mainArtifact );

maven-compat/src/main/java/org/apache/maven/artifact/installer/DefaultArtifactInstaller.java

@@ -40,6 +40,7 @@ import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
 import org.sonatype.aether.installation.InstallRequest;
 import org.sonatype.aether.installation.InstallationException;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.SubArtifact;
 
 /**
@@ -76,6 +77,8 @@ public class DefaultArtifactInstaller
 
         InstallRequest request = new InstallRequest();
 
+        request.setTrace( DefaultRequestTrace.newChild( null, legacySupport.getSession().getCurrentProject() ) );
+
         org.sonatype.aether.artifact.Artifact mainArtifact = RepositoryUtils.toArtifact( artifact );
         mainArtifact = mainArtifact.setFile( source );
         request.addArtifact( mainArtifact );

maven-core/src/main/java/org/apache/maven/plugin/internal/DefaultPluginDependenciesResolver.java

@@ -33,6 +33,7 @@ import org.codehaus.plexus.component.annotations.Requirement;
 import org.codehaus.plexus.logging.Logger;
 import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.artifact.Artifact;
 import org.sonatype.aether.collection.CollectRequest;
 import org.sonatype.aether.collection.DependencyCollectionException;
@@ -47,7 +48,10 @@ import org.sonatype.aether.resolution.ArtifactDescriptorRequest;
 import org.sonatype.aether.resolution.ArtifactDescriptorResult;
 import org.sonatype.aether.resolution.ArtifactRequest;
 import org.sonatype.aether.resolution.ArtifactResolutionException;
+import org.sonatype.aether.resolution.DependencyRequest;
+import org.sonatype.aether.resolution.DependencyResolutionException;
 import org.sonatype.aether.util.DefaultRepositorySystemSession;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.FilterRepositorySystemSession;
 import org.sonatype.aether.util.artifact.DefaultArtifact;
 import org.sonatype.aether.util.artifact.JavaScopes;
@@ -90,6 +94,8 @@ public class DefaultPluginDependenciesResolver
     public Artifact resolve( Plugin plugin, List<RemoteRepository> repositories, RepositorySystemSession session )
         throws PluginResolutionException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( null, plugin );
+
         Artifact pluginArtifact = toArtifact( plugin, session );
 
         try
@@ -105,6 +111,7 @@ public class DefaultPluginDependenciesResolver
 
             ArtifactDescriptorRequest request =
                 new ArtifactDescriptorRequest( pluginArtifact, repositories, REPOSITORY_CONTEXT );
+            request.setTrace( trace );
             ArtifactDescriptorResult result = repoSystem.readArtifactDescriptor( pluginSession, request );
 
             pluginArtifact = result.getArtifact();
@@ -125,6 +132,7 @@ public class DefaultPluginDependenciesResolver
         try
         {
             ArtifactRequest request = new ArtifactRequest( pluginArtifact, repositories, REPOSITORY_CONTEXT );
+            request.setTrace( trace );
             pluginArtifact = repoSystem.resolveArtifact( session, request ).getArtifact();
         }
         catch ( ArtifactResolutionException e )
@@ -139,6 +147,8 @@ public class DefaultPluginDependenciesResolver
                                    List<RemoteRepository> repositories, RepositorySystemSession session )
         throws PluginResolutionException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( null, plugin );
+
         if ( pluginArtifact == null )
         {
             pluginArtifact = toArtifact( plugin, session );
@@ -181,6 +191,11 @@ public class DefaultPluginDependenciesResolver
                 request.addDependency( pluginDep );
             }
 
+            DependencyRequest depRequest = new DependencyRequest( request, resolutionFilter );
+            depRequest.setTrace( trace );
+
+            request.setTrace( DefaultRequestTrace.newChild( trace, depRequest ) );
+
             node = repoSystem.collectDependencies( pluginSession, request ).getRoot();
 
             if ( logger.isDebugEnabled() )
@@ -188,15 +203,16 @@ public class DefaultPluginDependenciesResolver
                 node.accept( new GraphLogger() );
             }
 
-            repoSystem.resolveDependencies( session, node, resolutionFilter );
+            depRequest.setRoot( node );
+            repoSystem.resolveDependencies( session, depRequest );
         }
         catch ( DependencyCollectionException e )
         {
             throw new PluginResolutionException( plugin, e );
         }
-        catch ( ArtifactResolutionException e )
+        catch ( DependencyResolutionException e )
         {
-            throw new PluginResolutionException( plugin, e );
+            throw new PluginResolutionException( plugin, e.getCause() );
         }
 
         return node;

maven-core/src/main/java/org/apache/maven/plugin/prefix/internal/DefaultPluginPrefixResolver.java

@@ -42,12 +42,14 @@ import org.sonatype.aether.RepositoryEvent.EventType;
 import org.sonatype.aether.RepositoryListener;
 import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.repository.ArtifactRepository;
 import org.sonatype.aether.repository.RemoteRepository;
 import org.sonatype.aether.repository.RepositoryPolicy;
 import org.sonatype.aether.resolution.MetadataRequest;
 import org.sonatype.aether.resolution.MetadataResult;
 import org.sonatype.aether.util.DefaultRepositorySystemSession;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.listener.DefaultRepositoryEvent;
 import org.sonatype.aether.util.metadata.DefaultMetadata;
 
@@ -161,6 +163,8 @@ public class DefaultPluginPrefixResolver
 
     private PluginPrefixResult resolveFromRepository( PluginPrefixRequest request )
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( null, request );
+
         List<MetadataRequest> requests = new ArrayList<MetadataRequest>();
 
         for ( String pluginGroup : request.getPluginGroups() )
@@ -168,11 +172,11 @@ public class DefaultPluginPrefixResolver
             org.sonatype.aether.metadata.Metadata metadata =
                 new DefaultMetadata( pluginGroup, "maven-metadata.xml", DefaultMetadata.Nature.RELEASE_OR_SNAPSHOT );
 
-            requests.add( new MetadataRequest( metadata, null, REPOSITORY_CONTEXT ) );
+            requests.add( new MetadataRequest( metadata, null, REPOSITORY_CONTEXT ).setTrace( trace ) );
 
             for ( RemoteRepository repository : request.getRepositories() )
             {
-                requests.add( new MetadataRequest( metadata, repository, REPOSITORY_CONTEXT ) );
+                requests.add( new MetadataRequest( metadata, repository, REPOSITORY_CONTEXT ).setTrace( trace ) );
             }
         }
 
@@ -181,7 +185,7 @@ public class DefaultPluginPrefixResolver
         List<MetadataResult> results = repositorySystem.resolveMetadata( request.getRepositorySession(), requests );
         requests.clear();
 
-        PluginPrefixResult result = processResults( request, results, requests );
+        PluginPrefixResult result = processResults( request, trace, results, requests );
 
         if ( result != null )
         {
@@ -198,14 +202,14 @@ public class DefaultPluginPrefixResolver
 
             results = repositorySystem.resolveMetadata( session, requests );
 
-            return processResults( request, results, null );
+            return processResults( request, trace, results, null );
         }
 
         return null;
     }
 
-    private PluginPrefixResult processResults( PluginPrefixRequest request, List<MetadataResult> results,
+    private PluginPrefixResult processResults( PluginPrefixRequest request, RequestTrace trace,
-                                               List<MetadataRequest> requests )
+                                               List<MetadataResult> results, List<MetadataRequest> requests )
     {
         for ( MetadataResult res : results )
         {
@@ -220,7 +224,7 @@ public class DefaultPluginPrefixResolver
                 }
 
                 PluginPrefixResult result =
-                    resolveFromRepository( request, metadata.getGroupId(), metadata, repository );
+                    resolveFromRepository( request, trace, metadata.getGroupId(), metadata, repository );
 
                 if ( result != null )
                 {
@@ -237,7 +241,8 @@ public class DefaultPluginPrefixResolver
         return null;
     }
 
-    private PluginPrefixResult resolveFromRepository( PluginPrefixRequest request, String pluginGroup,
+    private PluginPrefixResult resolveFromRepository( PluginPrefixRequest request, RequestTrace trace,
+                                                      String pluginGroup,
                                                       org.sonatype.aether.metadata.Metadata metadata,
                                                       ArtifactRepository repository )
     {
@@ -264,20 +269,21 @@ public class DefaultPluginPrefixResolver
             }
             catch ( IOException e )
             {
-                invalidMetadata( request.getRepositorySession(), metadata, repository, e );
+                invalidMetadata( request.getRepositorySession(), trace, metadata, repository, e );
             }
         }
 
         return null;
     }
 
-    private void invalidMetadata( RepositorySystemSession session, org.sonatype.aether.metadata.Metadata metadata,
+    private void invalidMetadata( RepositorySystemSession session, RequestTrace trace,
-                                  ArtifactRepository repository, Exception exception )
+                                  org.sonatype.aether.metadata.Metadata metadata, ArtifactRepository repository,
+                                  Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session );
+            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session, trace );
             event.setMetadata( metadata );
             event.setException( exception );
             event.setRepository( repository );

maven-core/src/main/java/org/apache/maven/plugin/version/internal/DefaultPluginVersionResolver.java

@@ -47,10 +47,12 @@ import org.sonatype.aether.RepositoryEvent.EventType;
 import org.sonatype.aether.RepositoryListener;
 import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.repository.ArtifactRepository;
 import org.sonatype.aether.repository.RemoteRepository;
 import org.sonatype.aether.resolution.MetadataRequest;
 import org.sonatype.aether.resolution.MetadataResult;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.listener.DefaultRepositoryEvent;
 import org.sonatype.aether.util.metadata.DefaultMetadata;
 import org.sonatype.aether.util.version.GenericVersionScheme;
@@ -112,6 +114,8 @@ public class DefaultPluginVersionResolver
     private PluginVersionResult resolveFromRepository( PluginVersionRequest request )
         throws PluginVersionResolutionException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( null, request );
+
         DefaultPluginVersionResult result = new DefaultPluginVersionResult();
 
         org.sonatype.aether.metadata.Metadata metadata =
@@ -120,11 +124,11 @@ public class DefaultPluginVersionResolver
 
         List<MetadataRequest> requests = new ArrayList<MetadataRequest>();
 
-        requests.add( new MetadataRequest( metadata, null, REPOSITORY_CONTEXT ) );
+        requests.add( new MetadataRequest( metadata, null, REPOSITORY_CONTEXT ).setTrace( trace ) );
 
         for ( RemoteRepository repository : request.getRepositories() )
         {
-            requests.add( new MetadataRequest( metadata, repository, REPOSITORY_CONTEXT ) );
+            requests.add( new MetadataRequest( metadata, repository, REPOSITORY_CONTEXT ).setTrace( trace ) );
         }
 
         List<MetadataResult> results = repositorySystem.resolveMetadata( request.getRepositorySession(), requests );
@@ -139,7 +143,7 @@ public class DefaultPluginVersionResolver
                 repository = request.getRepositorySession().getLocalRepository();
             }
 
-            mergeMetadata( request.getRepositorySession(), versions, res.getMetadata(), repository );
+            mergeMetadata( request.getRepositorySession(), trace, versions, res.getMetadata(), repository );
         }
 
         selectVersion( result, request, versions );
@@ -275,7 +279,7 @@ public class DefaultPluginVersionResolver
         return true;
     }
 
-    private void mergeMetadata( RepositorySystemSession session, Versions versions,
+    private void mergeMetadata( RepositorySystemSession session, RequestTrace trace, Versions versions,
                                 org.sonatype.aether.metadata.Metadata metadata, ArtifactRepository repository )
     {
         if ( metadata != null && metadata.getFile() != null && metadata.getFile().isFile() )
@@ -290,18 +294,19 @@ public class DefaultPluginVersionResolver
             }
             catch ( IOException e )
             {
-                invalidMetadata( session, metadata, repository, e );
+                invalidMetadata( session, trace, metadata, repository, e );
             }
         }
     }
 
-    private void invalidMetadata( RepositorySystemSession session, org.sonatype.aether.metadata.Metadata metadata,
+    private void invalidMetadata( RepositorySystemSession session, RequestTrace trace,
-                                  ArtifactRepository repository, Exception exception )
+                                  org.sonatype.aether.metadata.Metadata metadata, ArtifactRepository repository,
+                                  Exception exception )
     {
         RepositoryListener listener = session.getRepositoryListener();
         if ( listener != null )
         {
-            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session );
+            DefaultRepositoryEvent event = new DefaultRepositoryEvent( EventType.METADATA_INVALID, session, trace );
             event.setMetadata( metadata );
             event.setException( exception );
             event.setRepository( repository );

maven-core/src/main/java/org/apache/maven/project/DefaultProjectBuilder.java

@@ -50,12 +50,14 @@ import org.codehaus.plexus.logging.Logger;
 import org.codehaus.plexus.util.Os;
 import org.codehaus.plexus.util.StringUtils;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.impl.RemoteRepositoryManager;
 import org.sonatype.aether.repository.LocalRepositoryManager;
 import org.sonatype.aether.repository.RemoteRepository;
 import org.sonatype.aether.repository.WorkspaceRepository;
 import org.sonatype.aether.resolution.ArtifactRequest;
 import org.sonatype.aether.resolution.ArtifactResult;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.SubArtifact;
 
 /**
@@ -213,12 +215,14 @@ public class DefaultProjectBuilder
     {
         ProjectBuildingRequest configuration = config.request;
 
-        ModelResolver resolver =
-            new ProjectModelResolver( config.session, repoSystem, repositoryManager, config.repositories,
-                                      configuration.getRepositoryMerging(), config.modelPool );
-
         ModelBuildingRequest request = new DefaultModelBuildingRequest();
 
+        RequestTrace trace = DefaultRequestTrace.newChild( null, configuration ).newChild( request );
+
+        ModelResolver resolver =
+            new ProjectModelResolver( config.session, trace, repoSystem, repositoryManager, config.repositories,
+                                      configuration.getRepositoryMerging(), config.modelPool );
+
         request.setValidationLevel( configuration.getValidationLevel() );
         request.setProcessPlugins( configuration.isProcessPlugins() );
         request.setProfiles( configuration.getProfiles() );

maven-core/src/main/java/org/apache/maven/project/DefaultProjectDependenciesResolver.java

@@ -33,14 +33,16 @@ import org.codehaus.plexus.component.annotations.Requirement;
 import org.codehaus.plexus.logging.Logger;
 import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.artifact.ArtifactTypeRegistry;
 import org.sonatype.aether.collection.CollectRequest;
 import org.sonatype.aether.collection.DependencyCollectionException;
 import org.sonatype.aether.graph.DependencyFilter;
 import org.sonatype.aether.graph.DependencyNode;
 import org.sonatype.aether.graph.DependencyVisitor;
-import org.sonatype.aether.resolution.ArtifactResolutionException;
 import org.sonatype.aether.resolution.ArtifactResult;
+import org.sonatype.aether.resolution.DependencyRequest;
+import org.sonatype.aether.util.DefaultRequestTrace;
 import org.sonatype.aether.util.artifact.JavaScopes;
 
 /**
@@ -60,6 +62,8 @@ public class DefaultProjectDependenciesResolver
     public DependencyResolutionResult resolve( DependencyResolutionRequest request )
         throws DependencyResolutionException
     {
+        RequestTrace trace = DefaultRequestTrace.newChild( null, request );
+
         DefaultDependencyResolutionResult result = new DefaultDependencyResolutionResult();
 
         MavenProject project = request.getMavenProject();
@@ -113,9 +117,13 @@ public class DefaultProjectDependenciesResolver
             }
         }
 
+        DependencyRequest depRequest = new DependencyRequest( collect, filter );
+        depRequest.setTrace( trace );
+
         DependencyNode node;
         try
         {
+            collect.setTrace( DefaultRequestTrace.newChild( trace, depRequest ) );
             node = repoSystem.collectDependencies( session, collect ).getRoot();
             result.setDependencyGraph( node );
         }
@@ -128,6 +136,8 @@ public class DefaultProjectDependenciesResolver
                 + project.getId() + ": " + e.getMessage(), e );
         }
 
+        depRequest.setRoot( node );
+
         if ( logger.isWarnEnabled() )
         {
             for ( DependencyNode child : node.getChildren() )
@@ -147,11 +157,11 @@ public class DefaultProjectDependenciesResolver
 
         try
         {
-            process( result, repoSystem.resolveDependencies( session, node, filter ) );
+            process( result, repoSystem.resolveDependencies( session, depRequest ).getArtifactResults() );
         }
-        catch ( ArtifactResolutionException e )
+        catch ( org.sonatype.aether.resolution.DependencyResolutionException e )
         {
-            process( result, e.getResults() );
+            process( result, e.getResult().getArtifactResults() );
 
             throw new DependencyResolutionException( result, "Could not resolve dependencies for project "
                 + project.getId() + ": " + e.getMessage(), e );
@@ -167,7 +177,6 @@ public class DefaultProjectDependenciesResolver
             DependencyNode node = ar.getRequest().getDependencyNode();
             if ( ar.isResolved() )
             {
-                node.setArtifact( ar.getArtifact() );
                 result.addResolvedDependency( node.getDependency() );
             }
             else

maven-core/src/main/java/org/apache/maven/project/ProjectModelResolver.java

@@ -34,6 +34,7 @@ import org.apache.maven.model.resolution.ModelResolver;
 import org.apache.maven.model.resolution.UnresolvableModelException;
 import org.sonatype.aether.RepositorySystem;
 import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.RequestTrace;
 import org.sonatype.aether.artifact.Artifact;
 import org.sonatype.aether.impl.RemoteRepositoryManager;
 import org.sonatype.aether.repository.RemoteRepository;
@@ -54,6 +55,8 @@ class ProjectModelResolver
 
     private final RepositorySystemSession session;
 
+    private final RequestTrace trace;
+
     private final String context = "project";
 
     private List<RemoteRepository> repositories;
@@ -72,11 +75,12 @@ class ProjectModelResolver
 
     private final ProjectBuildingRequest.RepositoryMerging repositoryMerging;
 
-    public ProjectModelResolver( RepositorySystemSession session, RepositorySystem resolver,
+    public ProjectModelResolver( RepositorySystemSession session, RequestTrace trace, RepositorySystem resolver,
                                  RemoteRepositoryManager remoteRepositoryManager, List<RemoteRepository> repositories,
                                  ProjectBuildingRequest.RepositoryMerging repositoryMerging, ReactorModelPool modelPool )
     {
         this.session = session;
+        this.trace = trace;
         this.resolver = resolver;
         this.remoteRepositoryManager = remoteRepositoryManager;
         this.pomRepositories = new ArrayList<RemoteRepository>();
@@ -90,6 +94,7 @@ class ProjectModelResolver
     private ProjectModelResolver( ProjectModelResolver original )
     {
         this.session = original.session;
+        this.trace = original.trace;
         this.resolver = original.resolver;
         this.remoteRepositoryManager = original.remoteRepositoryManager;
         this.pomRepositories = original.pomRepositories;
@@ -176,6 +181,7 @@ class ProjectModelResolver
             try
             {
                 ArtifactRequest request = new ArtifactRequest( pomArtifact, repositories, context );
+                request.setTrace( trace );
                 pomArtifact = resolver.resolveArtifact( session, request ).getArtifact();
             }
             catch ( ArtifactResolutionException e )