feat(features): decouple features service from Pax URL

assemblies/features/framework/pom.xml

@@ -186,6 +186,11 @@
             <groupId>org.apache.karaf.features</groupId>
             <artifactId>org.apache.karaf.features.core</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.apache.karaf.maven</groupId>
+            <artifactId>org.apache.karaf.maven.resolver.paxurl</artifactId>
+            <version>${project.version}</version>
+        </dependency>
 
     </dependencies>
 

assemblies/features/framework/src/main/feature/feature.xml

@@ -44,6 +44,7 @@
         <bundle start-level="11">mvn:org.apache.felix/org.apache.felix.configurator/${felix.configurator.version}</bundle>
         <bundle start-level="11">mvn:org.apache.karaf.config/org.apache.karaf.config.core/${project.version}</bundle>
         <!-- features service -->
+        <bundle start-level="14">mvn:org.apache.karaf.maven/org.apache.karaf.maven.resolver.paxurl/${project.version}</bundle>
         <bundle start-level="15">mvn:org.apache.karaf.features/org.apache.karaf.features.core/${project.version}</bundle>
         <bundle dependency="true" start-level="14">mvn:jakarta.xml.bind/jakarta.xml.bind-api/${spec.jaxb-api.version}</bundle>
         <bundle dependency="true" start-level="14">mvn:org.glassfish.jaxb/jaxb-runtime/${spec.jaxb.version}</bundle>
@@ -76,6 +77,7 @@
         <!-- file install -->
         <bundle start-level="12">mvn:org.apache.felix/org.apache.felix.fileinstall/${felix.fileinstall.version}</bundle>
         <!-- features service -->
+        <bundle start-level="14">mvn:org.apache.karaf.maven/org.apache.karaf.maven.resolver.paxurl/${project.version}</bundle>
         <bundle start-level="15">mvn:org.apache.karaf.features/org.apache.karaf.features.core/${project.version}</bundle>
         <bundle dependency="true" start-level="14">mvn:jakarta.xml.bind/jakarta.xml.bind-api/${spec.jaxb-api.version}</bundle>
         <bundle dependency="true" start-level="14">mvn:org.glassfish.jaxb/jaxb-runtime/${spec.jaxb.version}</bundle>

features/command/src/main/java/org/apache/karaf/features/command/FeatureExport.java

@@ -33,7 +33,7 @@
 import org.apache.karaf.shell.api.action.lifecycle.Reference;
 import org.apache.karaf.shell.api.action.lifecycle.Service;
 import org.apache.karaf.shell.support.completers.FileCompleter;
-import org.ops4j.pax.url.mvn.MavenResolver;
+import org.apache.karaf.features.spi.MavenResolver;
 
 /**
  * Simple {@link FeaturesCommandSupport} implementation that allows a user in

features/core/pom.xml

@@ -129,24 +129,6 @@
             <scope>provided</scope>
         </dependency>
 
-        <dependency>
-            <groupId>org.ops4j.pax.url</groupId>
-            <artifactId>pax-url-aether</artifactId>
-        </dependency>
-
-        <dependency>
-            <groupId>org.ops4j.base</groupId>
-            <artifactId>ops4j-base-util-property</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.ops4j.base</groupId>
-            <artifactId>ops4j-base-util-collections</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.ops4j.pax.swissbox</groupId>
-            <artifactId>pax-swissbox-property</artifactId>
-        </dependency>
-
         <dependency>
             <groupId>jakarta.activation</groupId>
             <artifactId>jakarta.activation-api</artifactId>
@@ -158,12 +140,6 @@
             <scope>test</scope>
         </dependency>
 
-        <dependency>
-            <groupId>org.ops4j.pax.tinybundles</groupId>
-            <artifactId>tinybundles</artifactId>
-            <scope>test</scope>
-        </dependency>
-
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest</artifactId>
@@ -214,6 +190,7 @@
                     <instructions>
                         <Export-Package>
                             org.apache.karaf.features,
+                            org.apache.karaf.features.spi,
                             org.apache.karaf.features.management,
                             org.apache.karaf.features.management.codec;-noimport:=true,
                             org.osgi.service.repository,
@@ -248,9 +225,6 @@
                             org.apache.karaf.util.xml,
                             org.eclipse.equinox.internal.region.*;-split-package:=merge-first,
                             org.apache.felix.resolver.*,
-                            org.ops4j.pax.swissbox.*,
-                            org.ops4j.util.*,
-                            org.ops4j.lang.*,
                             com.fasterxml.jackson*
                         </Private-Package>
                         <Embed-Dependency>

features/core/src/main/java/org/apache/karaf/features/internal/download/DownloadManagers.java

@@ -19,7 +19,7 @@
 import java.util.concurrent.ScheduledExecutorService;
 
 import org.apache.karaf.features.internal.download.impl.MavenDownloadManager;
-import org.ops4j.pax.url.mvn.MavenResolver;
+import org.apache.karaf.features.spi.MavenResolver;
 
 public final class DownloadManagers {
 

features/core/src/main/java/org/apache/karaf/features/internal/download/impl/LocalMavenResolver.java

@@ -0,0 +1,81 @@
+/*
+ * 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.
+ */
+package org.apache.karaf.features.internal.download.impl;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import org.apache.karaf.features.spi.MavenResolver;
+import org.apache.karaf.util.maven.Parser;
+
+/**
+ * Resolves Maven coordinates from the Karaf distribution's local system repository only.
+ */
+public class LocalMavenResolver implements MavenResolver {
+
+    private final Path systemRepository;
+
+    public LocalMavenResolver(Path systemRepository) {
+        this.systemRepository = systemRepository.toAbsolutePath().normalize();
+    }
+
+    /**
+     * Create a resolver for the repository configured by the running Karaf distribution.
+     *
+     * @return a resolver rooted at {@code karaf.home/karaf.default.repository}.
+     */
+    public static LocalMavenResolver forKarafSystem() {
+        Path home = Paths.get(System.getProperty("karaf.home", "karaf"));
+        Path repository = Paths.get(System.getProperty("karaf.default.repository", "system"));
+        if (!repository.isAbsolute()) {
+            repository = home.resolve(repository);
+        }
+        return new LocalMavenResolver(repository);
+    }
+
+    @Override
+    public File resolve(String url) throws IOException {
+        if (url == null || !url.startsWith("mvn:")) {
+            throw new MalformedURLException("Expected a mvn: URI: " + url);
+        }
+        String artifactPath = Parser.pathFromMaven(url);
+        Path artifact = systemRepository.resolve(artifactPath).normalize();
+        if (!artifact.startsWith(systemRepository)) {
+            throw new IOException("Maven artifact path is outside the Karaf system repository: " + url);
+        }
+        if (!artifact.toFile().isFile()) {
+            throw new FileNotFoundException("Maven artifact " + url + " was not found in the Karaf system repository "
+                    + systemRepository);
+        }
+        return artifact.toFile();
+    }
+
+    @Override
+    public File resolve(String url, Exception previousException) throws IOException {
+        return resolve(url);
+    }
+
+    @Override
+    public RetryChance isRetryableException(Exception exception) {
+        return RetryChance.NEVER;
+    }
+
+}

features/core/src/main/java/org/apache/karaf/features/internal/download/impl/MavenDownloadManager.java

@@ -29,7 +29,7 @@
 import org.apache.karaf.features.internal.download.Downloader;
 import org.apache.karaf.features.internal.download.StreamProvider;
 import org.apache.karaf.features.internal.util.MultiException;
-import org.ops4j.pax.url.mvn.MavenResolver;
+import org.apache.karaf.features.spi.MavenResolver;
 
 public class MavenDownloadManager implements DownloadManager {
 

features/core/src/main/java/org/apache/karaf/features/internal/download/impl/MavenDownloadTask.java

@@ -22,7 +22,7 @@
 import java.util.Objects;
 
 import org.apache.karaf.util.maven.Parser;
-import org.ops4j.pax.url.mvn.MavenResolver;
+import org.apache.karaf.features.spi.MavenResolver;
 
 public class MavenDownloadTask extends AbstractRetryableDownloadTask {
 

features/core/src/main/java/org/apache/karaf/features/internal/osgi/Activator.java

@@ -57,6 +57,7 @@
 import org.apache.karaf.features.internal.service.StateStorage;
 import org.apache.karaf.features.internal.util.SystemExitManager;
 import org.apache.karaf.util.ThreadUtils;
+import org.apache.karaf.features.spi.MavenResolverFactory;
 import org.apache.karaf.util.tracker.BaseActivator;
 import org.apache.karaf.util.tracker.annotation.ProvideService;
 import org.apache.karaf.util.tracker.annotation.RequireService;
@@ -76,15 +77,13 @@
 import org.osgi.service.cm.ManagedService;
 import org.osgi.service.repository.Repository;
 import org.osgi.service.resolver.Resolver;
-import org.osgi.service.url.URLStreamHandlerService;
 import org.osgi.util.tracker.ServiceTracker;
 import org.osgi.util.tracker.ServiceTrackerCustomizer;
 import org.slf4j.LoggerFactory;
 
 @Services(
     requires = {
-            @RequireService(ConfigurationAdmin.class),
-            @RequireService(value = URLStreamHandlerService.class, filter = "(url.handler.protocol=mvn)")
+            @RequireService(ConfigurationAdmin.class)
     },
     provides = {
             @ProvideService(FeaturesService.class),
@@ -102,6 +101,8 @@ public class Activator extends BaseActivator {
     private static final String STATE_FILE = "state.json";
 
     private ServiceTracker<FeaturesListener, FeaturesListener> featuresListenerTracker;
+    private ServiceTracker<MavenResolverFactory, MavenResolverFactory> mavenResolverFactoryTracker;
+    private volatile MavenResolverFactory mavenResolverFactory;
     private FeaturesServiceImpl featuresService;
     private SimpleFeaturesServiceImpl simpleFeaturesService;
     private StandardManageableRegionDigraph digraphMBean;
@@ -118,6 +119,32 @@ public Activator() {
     protected void doOpen() throws Exception {
         super.doOpen();
 
+        // Keep the Maven resolver optional so this service can start without Pax URL.
+        mavenResolverFactoryTracker = new ServiceTracker<>(bundleContext, MavenResolverFactory.class,
+                new ServiceTrackerCustomizer<MavenResolverFactory, MavenResolverFactory>() {
+                    @Override
+                    public MavenResolverFactory addingService(ServiceReference<MavenResolverFactory> reference) {
+                        MavenResolverFactory factory = bundleContext.getService(reference);
+                        setMavenResolverFactory(factory);
+                        return factory;
+                    }
+
+                    @Override
+                    public void modifiedService(ServiceReference<MavenResolverFactory> reference,
+                                                MavenResolverFactory factory) {
+                    }
+
+                    @Override
+                    public void removedService(ServiceReference<MavenResolverFactory> reference,
+                                               MavenResolverFactory factory) {
+                        if (mavenResolverFactory == factory) {
+                            setMavenResolverFactory(null);
+                        }
+                        bundleContext.ungetService(reference);
+                    }
+                });
+        mavenResolverFactoryTracker.open();
+
         Properties configuration = new Properties();
         File configFile = new File(System.getProperty("karaf.etc"), FEATURES_SERVICE_CONFIG_FILE);
         if (configFile.isFile() && configFile.canRead()) {
@@ -159,9 +186,8 @@ protected void doStart() throws Exception {
                 new LinkedBlockingQueue<>(),
                 ThreadUtils.namedThreadFactory("resolver"));
         Resolver resolver = new ResolverImpl(new Slf4jResolverLog(LoggerFactory.getLogger(ResolverImpl.class)), executorService);
-        URLStreamHandlerService mvnUrlHandler = getTrackedService(URLStreamHandlerService.class);
 
-        if (configurationAdmin == null || mvnUrlHandler == null) {
+        if (configurationAdmin == null) {
             return;
         }
 
@@ -200,6 +226,7 @@ protected void doStart() throws Exception {
                     configurationAdmin,
                     installSupport,
                     cfg);
+            simpleFeaturesService.setMavenResolverFactory(mavenResolverFactory);
             try {
                 EventAdminListener eventAdminListener = new EventAdminListener(bundleContext);
                 simpleFeaturesService.registerListener(eventAdminListener);
@@ -216,6 +243,7 @@ protected void doStart() throws Exception {
                     installSupport,
                     globalRepository,
                     cfg);
+            featuresService.setMavenResolverFactory(mavenResolverFactory);
             try {
                 EventAdminListener eventAdminListener = new EventAdminListener(bundleContext);
                 featuresService.registerListener(eventAdminListener);
@@ -394,4 +422,23 @@ protected void doStop() {
         }
     }
 
+    @Override
+    protected void doClose() {
+        if (mavenResolverFactoryTracker != null) {
+            mavenResolverFactoryTracker.close();
+            mavenResolverFactoryTracker = null;
+        }
+        super.doClose();
+    }
+
+    private void setMavenResolverFactory(MavenResolverFactory factory) {
+        mavenResolverFactory = factory;
+        if (featuresService != null) {
+            featuresService.setMavenResolverFactory(factory);
+        }
+        if (simpleFeaturesService != null) {
+            simpleFeaturesService.setMavenResolverFactory(factory);
+        }
+    }
+
 }

features/core/src/main/java/org/apache/karaf/features/internal/service/FeaturesProcessingSerializer.java

@@ -46,9 +46,8 @@
 import org.apache.karaf.features.internal.model.processing.FeaturesProcessing;
 import org.apache.karaf.features.internal.model.processing.ObjectFactory;
 import org.apache.karaf.util.xml.IndentingXMLEventWriter;
-import org.ops4j.pax.swissbox.property.BundleContextPropertyResolver;
-import org.ops4j.util.property.DictionaryPropertyResolver;
-import org.ops4j.util.property.PropertyResolver;
+import org.apache.karaf.features.internal.util.PropertyResolver;
+import org.apache.karaf.features.internal.util.PropertySubstitutor;
 import org.osgi.framework.Bundle;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.FrameworkUtil;
@@ -106,9 +105,9 @@ public FeaturesProcessing read(InputStream stream, Properties versions) throws E
         Unmarshaller unmarshaller = FEATURES_PROCESSING_CONTEXT.createUnmarshaller();
         UnmarshallerHandler handler = unmarshaller.getUnmarshallerHandler();
 
-        // BundleContextPropertyResolver gives access to e.g., ${karaf.base}
-        final PropertyResolver resolver = bundleContext == null ? new DictionaryPropertyResolver(versions)
-                : new DictionaryPropertyResolver(versions, new BundleContextPropertyResolver(bundleContext));
+        // the bundle context resolver gives access to e.g., ${karaf.base}
+        final PropertyResolver resolver = bundleContext == null ? PropertyResolver.forDictionary(versions)
+                : PropertyResolver.forDictionary(versions, PropertyResolver.forBundleContext(bundleContext));
 
         // indirect unmarshaling with property resolution inside XML attribute values and CDATA
         SAXParserFactory spf = SAXParserFactory.newInstance();
@@ -314,7 +313,7 @@ private void flushBuffer(boolean resolve) throws SAXException {
         }
 
         private String resolve(String value) {
-            String resolved = org.ops4j.util.collections.PropertyResolver.resolve(properties, value);
+            String resolved = PropertySubstitutor.substitute(properties, value);
             if (resolved.contains("${")) {
                 // there are still unresolved properties - just log warning
                 LOG.warn("Value {} has unresolved properties, please check configuration.", value);