[MNG-7055] Fix G level metadata handling (#555)

Maven Artifact Transfer silently prevents group level metadata to reach Resolver and causes metadata loss on install/deploy. Fix is to "bridge" this from maven-resolver-provider (and core) by reusing the actual metadata that m-plugin-p:addPluginArtifactMetadata mojo adds, but m-a-t filters out.
diff --git a/maven-compat/pom.xml b/maven-compat/pom.xml
index ed90947..7f8d4a3 100644
--- a/maven-compat/pom.xml
+++ b/maven-compat/pom.xml
@@ -109,6 +109,11 @@
       <scope>test</scope>
     </dependency>
     <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
       <groupId>org.apache.maven.wagon</groupId>
       <artifactId>wagon-file</artifactId>
       <scope>test</scope>
diff --git a/maven-compat/src/test/java/org/apache/maven/artifact/deployer/ArtifactDeployerTest.java b/maven-compat/src/test/java/org/apache/maven/artifact/deployer/ArtifactDeployerTest.java
index 53cc388..3f33fa1 100644
--- a/maven-compat/src/test/java/org/apache/maven/artifact/deployer/ArtifactDeployerTest.java
+++ b/maven-compat/src/test/java/org/apache/maven/artifact/deployer/ArtifactDeployerTest.java
@@ -24,12 +24,15 @@
 import org.apache.maven.artifact.AbstractArtifactComponentTestCase;
 import org.apache.maven.artifact.Artifact;
 import org.apache.maven.artifact.repository.ArtifactRepository;
+import org.apache.maven.execution.MavenSession;
+import org.apache.maven.session.scope.internal.SessionScope;
 import org.codehaus.plexus.util.FileUtils;
 import org.junit.jupiter.api.Test;
 
 import static org.codehaus.plexus.testing.PlexusExtension.getBasedir;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mock;
 
 import javax.inject.Inject;
 
@@ -42,6 +45,9 @@
     @Inject
     private ArtifactDeployer artifactDeployer;
 
+    @Inject
+    private SessionScope sessionScope;
+
     protected String component()
     {
         return "deployer";
@@ -51,18 +57,28 @@
     public void testArtifactInstallation()
         throws Exception
     {
-        String artifactBasedir = new File( getBasedir(), "src/test/resources/artifact-install" ).getAbsolutePath();
+        sessionScope.enter();
+        try
+        {
+            sessionScope.seed(MavenSession.class, mock(MavenSession.class));
 
-        Artifact artifact = createArtifact( "artifact", "1.0" );
+            String artifactBasedir = new File( getBasedir(), "src/test/resources/artifact-install" ).getAbsolutePath();
 
-        File file = new File( artifactBasedir, "artifact-1.0.jar" );
-        assertEquals( "dummy", FileUtils.fileRead( file, "UTF-8" ).trim() );
+            Artifact artifact = createArtifact( "artifact", "1.0" );
 
-        artifactDeployer.deploy( file, artifact, remoteRepository(), localRepository() );
+            File file = new File( artifactBasedir, "artifact-1.0.jar" );
+            assertEquals( "dummy", FileUtils.fileRead( file, "UTF-8" ).trim() );
 
-        ArtifactRepository remoteRepository = remoteRepository();
-        File deployedFile = new File( remoteRepository.getBasedir(), remoteRepository.pathOf( artifact ) );
-        assertTrue( deployedFile.exists() );
-        assertEquals( "dummy", FileUtils.fileRead( deployedFile, "UTF-8" ).trim() );
+            artifactDeployer.deploy( file, artifact, remoteRepository(), localRepository() );
+
+            ArtifactRepository remoteRepository = remoteRepository();
+            File deployedFile = new File( remoteRepository.getBasedir(), remoteRepository.pathOf( artifact ) );
+            assertTrue( deployedFile.exists() );
+            assertEquals( "dummy", FileUtils.fileRead( deployedFile, "UTF-8" ).trim() );
+        }
+        finally
+        {
+            sessionScope.exit();
+        }
     }
 }
\ No newline at end of file
diff --git a/maven-compat/src/test/java/org/apache/maven/artifact/installer/ArtifactInstallerTest.java b/maven-compat/src/test/java/org/apache/maven/artifact/installer/ArtifactInstallerTest.java
index ca99ab2..afa2761 100644
--- a/maven-compat/src/test/java/org/apache/maven/artifact/installer/ArtifactInstallerTest.java
+++ b/maven-compat/src/test/java/org/apache/maven/artifact/installer/ArtifactInstallerTest.java
@@ -23,11 +23,14 @@
 
 import org.apache.maven.artifact.AbstractArtifactComponentTestCase;
 import org.apache.maven.artifact.Artifact;
+import org.apache.maven.execution.MavenSession;
+import org.apache.maven.session.scope.internal.SessionScope;
 import org.junit.jupiter.api.Test;
 
 import javax.inject.Inject;
 
 import static org.codehaus.plexus.testing.PlexusExtension.getBasedir;
+import static org.mockito.Mockito.mock;
 
 /**
  * @author <a href="mailto:jason@maven.org">Jason van Zyl</a>
@@ -38,6 +41,9 @@
     @Inject
     private ArtifactInstaller artifactInstaller;
 
+    @Inject
+    private SessionScope sessionScope;
+
     protected String component()
     {
         return "installer";
@@ -47,14 +53,24 @@
     public void testArtifactInstallation()
         throws Exception
     {
-        String artifactBasedir = new File( getBasedir(), "src/test/resources/artifact-install" ).getAbsolutePath();
+        sessionScope.enter();
+        try
+        {
+            sessionScope.seed(MavenSession.class, mock(MavenSession.class));
 
-        Artifact artifact = createArtifact( "artifact", "1.0" );
+            String artifactBasedir = new File( getBasedir(), "src/test/resources/artifact-install" ).getAbsolutePath();
 
-        File source = new File( artifactBasedir, "artifact-1.0.jar" );
+            Artifact artifact = createArtifact( "artifact", "1.0" );
 
-        artifactInstaller.install( source, artifact, localRepository() );
+            File source = new File( artifactBasedir, "artifact-1.0.jar" );
 
-        assertLocalArtifactPresent( artifact );
+            artifactInstaller.install( source, artifact, localRepository() );
+
+            assertLocalArtifactPresent( artifact );
+        }
+        finally
+        {
+            sessionScope.exit();
+        }
     }
 }
\ No newline at end of file
diff --git a/maven-core/src/main/java/org/apache/maven/execution/infoproviders/DefaultPluginsMetadataInfoProvider.java b/maven-core/src/main/java/org/apache/maven/execution/infoproviders/DefaultPluginsMetadataInfoProvider.java
new file mode 100644
index 0000000..616a3a8
--- /dev/null
+++ b/maven-core/src/main/java/org/apache/maven/execution/infoproviders/DefaultPluginsMetadataInfoProvider.java
@@ -0,0 +1,137 @@
+package org.apache.maven.execution.infoproviders;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.util.Objects;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Provider;
+import javax.inject.Singleton;
+
+import org.apache.maven.artifact.repository.metadata.Metadata;
+import org.apache.maven.artifact.repository.metadata.Plugin;
+import org.apache.maven.artifact.repository.metadata.RepositoryMetadata;
+import org.apache.maven.execution.MavenSession;
+import org.apache.maven.project.MavenProject;
+import org.apache.maven.repository.internal.PluginsMetadataInfoProvider;
+import org.apache.maven.repository.legacy.metadata.ArtifactMetadata;
+import org.eclipse.aether.artifact.Artifact;
+
+import static java.util.Objects.requireNonNull;
+
+/**
+ * Default implementation of {@link PluginsMetadataInfoProvider}.
+ */
+@Named
+@Singleton
+public class DefaultPluginsMetadataInfoProvider
+    implements PluginsMetadataInfoProvider
+{
+    private final Provider<MavenSession> mavenSessionProvider;
+
+    @Inject
+    public DefaultPluginsMetadataInfoProvider( final Provider<MavenSession> mavenSessionProvider )
+    {
+        this.mavenSessionProvider = requireNonNull( mavenSessionProvider );
+    }
+
+    @Override
+    public PluginInfo getPluginInfo( final Artifact artifact )
+    {
+        MavenSession mavenSession = mavenSessionProvider.get();
+        if ( mavenSession != null )
+        {
+            MavenProject mavenProject = searchForProject( mavenSession, artifact );
+            if ( mavenProject != null && "maven-plugin".equals( mavenProject.getPackaging() ) )
+            {
+                Plugin plugin = searchForPluginGroupLevelRepositoryMetadata( mavenProject );
+
+                if ( plugin != null )
+                {
+                    return new PluginInfo()
+                    {
+                        @Override
+                        public String getPluginGroupId()
+                        {
+                            return artifact.getGroupId();
+                        }
+
+                        @Override
+                        public String getPluginArtifactId()
+                        {
+                            return artifact.getArtifactId();
+                        }
+
+                        @Override
+                        public String getPluginPrefix()
+                        {
+                            return plugin.getPrefix();
+                        }
+
+                        @Override
+                        public String getPluginName()
+                        {
+                            return plugin.getName();
+                        }
+                    };
+                }
+            }
+        }
+
+        return null;
+    }
+
+    private MavenProject searchForProject( MavenSession mavenSession, Artifact artifact )
+    {
+        for ( MavenProject mavenProject : mavenSession.getProjects() )
+        {
+            if ( mavenProject.getArtifact() != null
+                && Objects.equals( mavenProject.getGroupId(), artifact.getGroupId() )
+                && Objects.equals( mavenProject.getArtifactId(), artifact.getArtifactId() ) )
+            {
+                return mavenProject;
+            }
+        }
+        return null;
+    }
+
+    private Plugin searchForPluginGroupLevelRepositoryMetadata( MavenProject mavenProject )
+    {
+        org.apache.maven.artifact.Artifact projectArtifact = mavenProject.getArtifact();
+        for ( ArtifactMetadata artifactMetadata : projectArtifact.getMetadataList() )
+        {
+            if ( artifactMetadata instanceof RepositoryMetadata )
+            {
+                RepositoryMetadata repositoryMetadata = (RepositoryMetadata) artifactMetadata;
+                Metadata metadata = repositoryMetadata.getMetadata();
+
+                for ( Plugin plugin : metadata.getPlugins() )
+                {
+                    if ( Objects.equals( plugin.getArtifactId(), mavenProject.getArtifactId() ) )
+                    {
+                        return plugin;
+                    }
+                }
+            }
+        }
+        return null;
+    }
+}
diff --git a/maven-core/src/main/java/org/apache/maven/lifecycle/mapping/providers/MavenPluginLifecycleMappingProvider.java b/maven-core/src/main/java/org/apache/maven/lifecycle/mapping/providers/MavenPluginLifecycleMappingProvider.java
index c01afc7..8ab0883 100644
--- a/maven-core/src/main/java/org/apache/maven/lifecycle/mapping/providers/MavenPluginLifecycleMappingProvider.java
+++ b/maven-core/src/main/java/org/apache/maven/lifecycle/mapping/providers/MavenPluginLifecycleMappingProvider.java
@@ -74,13 +74,11 @@
     );
     lifecyclePhases.put(
         "install",
-        // TODO: MNG-6556: Do not upgrade to 3.0.0-M1 is does not install the plugin prefix metadata
-        new LifecyclePhase( "org.apache.maven.plugins:maven-install-plugin:2.5.2:install" )
+        new LifecyclePhase( "org.apache.maven.plugins:maven-install-plugin:3.0.0-M1:install" )
     );
     lifecyclePhases.put(
         "deploy",
-        // TODO: MNG-6556: Do not upgrade to 3.0.0-M1 is does not install the plugin prefix metadata
-        new LifecyclePhase( "org.apache.maven.plugins:maven-deploy-plugin:2.8.2:deploy" )
+        new LifecyclePhase( "org.apache.maven.plugins:maven-deploy-plugin:3.0.0-M1:deploy" )
     );
 
     Lifecycle lifecycle = new Lifecycle();
diff --git a/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadata.java b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadata.java
new file mode 100644
index 0000000..7a6c45a
--- /dev/null
+++ b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadata.java
@@ -0,0 +1,117 @@
+package org.apache.maven.repository.internal;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.LinkedHashMap;
+import java.util.List;
+
+import org.apache.maven.artifact.repository.metadata.Metadata;
+import org.apache.maven.artifact.repository.metadata.Plugin;
+import org.apache.maven.repository.internal.PluginsMetadataInfoProvider.PluginInfo;
+import org.eclipse.aether.artifact.Artifact;
+
+/**
+ * Plugin G level metadata.
+ */
+final class PluginsMetadata
+    extends MavenMetadata
+{
+    private final PluginInfo pluginInfo;
+
+    PluginsMetadata( PluginInfo pluginInfo, Date timestamp )
+    {
+        super( createRepositoryMetadata( pluginInfo ), null, timestamp );
+        this.pluginInfo = pluginInfo;
+    }
+
+    PluginsMetadata( PluginInfo pluginInfo, File file, Date timestamp )
+    {
+        super( createRepositoryMetadata( pluginInfo ), file, timestamp );
+        this.pluginInfo = pluginInfo;
+    }
+
+    private static Metadata createRepositoryMetadata( PluginInfo pluginInfo )
+    {
+        Metadata result = new Metadata();
+        Plugin plugin = new Plugin();
+        plugin.setPrefix( pluginInfo.getPluginPrefix() );
+        plugin.setArtifactId( pluginInfo.getPluginArtifactId() );
+        plugin.setName( pluginInfo.getPluginName() );
+        result.getPlugins().add( plugin );
+        return result;
+    }
+
+    @Override
+    protected void merge( Metadata recessive )
+    {
+        List<Plugin> recessivePlugins = recessive.getPlugins();
+        List<Plugin> plugins = metadata.getPlugins();
+        if ( !plugins.isEmpty() )
+        {
+            LinkedHashMap<String, Plugin> mergedPlugins = new LinkedHashMap<>();
+            recessivePlugins.forEach( p -> mergedPlugins.put( p.getPrefix(), p ) );
+            plugins.forEach( p -> mergedPlugins.put( p.getPrefix(), p ) );
+            metadata.setPlugins( new ArrayList<>( mergedPlugins.values() ) );
+        }
+    }
+
+    public Object getKey()
+    {
+        return getGroupId();
+    }
+
+    public static Object getKey( Artifact artifact )
+    {
+        return artifact.getGroupId();
+    }
+
+    @Override
+    public MavenMetadata setFile( File file )
+    {
+        return new PluginsMetadata( pluginInfo, file, timestamp );
+    }
+
+    @Override
+    public String getGroupId()
+    {
+        return pluginInfo.getPluginGroupId();
+    }
+
+    @Override
+    public String getArtifactId()
+    {
+        return "";
+    }
+
+    @Override
+    public String getVersion()
+    {
+        return "";
+    }
+
+    @Override
+    public Nature getNature()
+    {
+        return Nature.RELEASE_OR_SNAPSHOT;
+    }
+}
diff --git a/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGenerator.java b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGenerator.java
new file mode 100644
index 0000000..4f35568
--- /dev/null
+++ b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGenerator.java
@@ -0,0 +1,130 @@
+package org.apache.maven.repository.internal;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.apache.maven.repository.internal.PluginsMetadataInfoProvider.PluginInfo;
+import org.eclipse.aether.RepositorySystemSession;
+import org.eclipse.aether.artifact.Artifact;
+import org.eclipse.aether.deployment.DeployRequest;
+import org.eclipse.aether.impl.MetadataGenerator;
+import org.eclipse.aether.installation.InstallRequest;
+import org.eclipse.aether.metadata.Metadata;
+import org.eclipse.aether.util.ConfigUtils;
+
+import static java.util.Objects.requireNonNull;
+
+/**
+ * Plugin G level metadata.
+ */
+class PluginsMetadataGenerator
+    implements MetadataGenerator
+{
+    private final PluginsMetadataInfoProvider pluginsMetadataInfoProvider;
+
+    private final Map<Object, PluginsMetadata> plugins;
+
+    private final Map<Object, PluginsMetadata> processedPlugins;
+
+    private final Date timestamp;
+
+    PluginsMetadataGenerator( PluginsMetadataInfoProvider pluginsMetadataInfoProvider,
+                              RepositorySystemSession session,
+                              InstallRequest request )
+    {
+        this( pluginsMetadataInfoProvider, session, request.getMetadata() );
+    }
+
+    PluginsMetadataGenerator( PluginsMetadataInfoProvider pluginsMetadataInfoProvider,
+                              RepositorySystemSession session,
+                              DeployRequest request )
+    {
+        this( pluginsMetadataInfoProvider, session, request.getMetadata() );
+    }
+
+    private PluginsMetadataGenerator( PluginsMetadataInfoProvider pluginsMetadataInfoProvider,
+                                      RepositorySystemSession session,
+                                      Collection<? extends Metadata> metadatas )
+    {
+        this.pluginsMetadataInfoProvider = requireNonNull( pluginsMetadataInfoProvider );
+        this.plugins = new LinkedHashMap<>();
+        this.processedPlugins = new LinkedHashMap<>();
+        this.timestamp = (Date) ConfigUtils.getObject( session, new Date(), "maven.startTime" );
+
+        /*
+         * NOTE: This should be considered a quirk to support interop with Maven's legacy ArtifactDeployer which
+         * processes one artifact at a time and hence cannot associate the artifacts from the same project to use the
+         * same version index. Allowing the caller to pass in metadata from a previous deployment allows to re-establish
+         * the association between the artifacts of the same project.
+         */
+        for ( Iterator<? extends Metadata> it = metadatas.iterator(); it.hasNext(); )
+        {
+            Metadata metadata = it.next();
+            if ( metadata instanceof PluginsMetadata )
+            {
+                it.remove();
+                PluginsMetadata pluginMetadata = ( PluginsMetadata ) metadata;
+                processedPlugins.put( pluginMetadata.getKey(), pluginMetadata );
+            }
+        }
+    }
+
+    @Override
+    public Collection<? extends Metadata> prepare( Collection<? extends Artifact> artifacts )
+    {
+        return Collections.emptyList();
+    }
+
+    @Override
+    public Artifact transformArtifact( Artifact artifact )
+    {
+        return artifact;
+    }
+
+    @Override
+    public Collection<? extends Metadata> finish( Collection<? extends Artifact> artifacts )
+    {
+        for ( Artifact artifact : artifacts )
+        {
+            PluginInfo pluginInfo = pluginsMetadataInfoProvider.getPluginInfo( artifact );
+            if ( pluginInfo != null )
+            {
+                Object key = PluginsMetadata.getKey( artifact );
+                if ( processedPlugins.get( key ) == null )
+                {
+                    PluginsMetadata pluginMetadata = plugins.get( key );
+                    if ( pluginMetadata == null )
+                    {
+                        pluginMetadata = new PluginsMetadata( pluginInfo, timestamp );
+                        plugins.put( key, pluginMetadata );
+                    }
+                }
+            }
+        }
+
+        return plugins.values();
+    }
+}
diff --git a/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGeneratorFactory.java b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGeneratorFactory.java
new file mode 100644
index 0000000..19d499b
--- /dev/null
+++ b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataGeneratorFactory.java
@@ -0,0 +1,67 @@
+package org.apache.maven.repository.internal;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Singleton;
+
+import org.eclipse.aether.RepositorySystemSession;
+import org.eclipse.aether.deployment.DeployRequest;
+import org.eclipse.aether.impl.MetadataGenerator;
+import org.eclipse.aether.impl.MetadataGeneratorFactory;
+import org.eclipse.aether.installation.InstallRequest;
+
+import static java.util.Objects.requireNonNull;
+
+/**
+ * Plugin G level metadata.
+ */
+@Named( "plugins" )
+@Singleton
+public class PluginsMetadataGeneratorFactory
+    implements MetadataGeneratorFactory
+{
+    private final PluginsMetadataInfoProvider pluginsMetadataInfoProvider;
+
+    @Inject
+    public PluginsMetadataGeneratorFactory( PluginsMetadataInfoProvider pluginsMetadataInfoProvider )
+    {
+        this.pluginsMetadataInfoProvider = requireNonNull( pluginsMetadataInfoProvider );
+    }
+
+    @Override
+    public MetadataGenerator newInstance( RepositorySystemSession session, InstallRequest request )
+    {
+        return new PluginsMetadataGenerator( pluginsMetadataInfoProvider, session, request );
+    }
+
+    @Override
+    public MetadataGenerator newInstance( RepositorySystemSession session, DeployRequest request )
+    {
+        return new PluginsMetadataGenerator( pluginsMetadataInfoProvider, session, request );
+    }
+
+    @Override
+    public float getPriority()
+    {
+        return 5;
+    }
+}
diff --git a/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataInfoProvider.java b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataInfoProvider.java
new file mode 100644
index 0000000..629a23f
--- /dev/null
+++ b/maven-resolver-provider/src/main/java/org/apache/maven/repository/internal/PluginsMetadataInfoProvider.java
@@ -0,0 +1,44 @@
+package org.apache.maven.repository.internal;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import org.eclipse.aether.artifact.Artifact;
+
+/**
+ * Plugin G level metadata provider.
+ */
+public interface PluginsMetadataInfoProvider
+{
+    interface PluginInfo
+    {
+        String getPluginGroupId();
+
+        String getPluginArtifactId();
+
+        String getPluginPrefix();
+
+        String getPluginName();
+    }
+
+    /**
+     * Returns {@link PluginInfo} corresponding for passed in {@link Artifact}, or {@code null}.
+     */
+    PluginInfo getPluginInfo( Artifact artifact );
+}