Backport CAMEL-23252 and CAMEL-23276 to 4.18.x

core/camel-api/src/main/java/org/apache/camel/spi/ContextServiceLoaderPluginResolver.java

@@ -38,4 +38,10 @@
  * @see StatefulService
  */
 public interface ContextServiceLoaderPluginResolver extends CamelContextAware, StatefulService {
+
+    /**
+     * Invokes {@link ContextServicePlugin#onReload(org.apache.camel.CamelContext)} on all discovered plugins, giving
+     * them an opportunity to refresh their state before routes are reloaded.
+     */
+    void onReload();
 }

core/camel-api/src/main/java/org/apache/camel/spi/ContextServicePlugin.java

@@ -67,6 +67,22 @@ public interface ContextServicePlugin {
      */
     void load(CamelContext camelContext);
 
+    /**
+     * Called before route reloading in development mode to allow the plugin to refresh its state.
+     * <p>
+     * This method is invoked by the route watcher reload strategy before routes are reloaded, giving plugins the
+     * opportunity to refresh bean references, re-read configuration, or perform other updates that should happen before
+     * the new routes are started.
+     * <p>
+     * The default implementation does nothing. Plugins that register beans or other resources that may become stale
+     * when properties change should override this method to refresh those resources.
+     *
+     * @param camelContext the CamelContext being reloaded, never {@code null}
+     */
+    default void onReload(CamelContext camelContext) {
+        // NO-OP
+    }
+
     /**
      * Called during CamelContext stop. Use it to free allocated resources.
      *

core/camel-base-engine/src/main/java/org/apache/camel/impl/engine/DefaultContextServiceLoaderPlugin.java

@@ -76,6 +76,21 @@ protected void doStart() throws Exception {
         }
     }
 
+    @Override
+    public void onReload() {
+        if (contextServicePlugins != null) {
+            for (ContextServicePlugin plugin : contextServicePlugins) {
+                try {
+                    plugin.onReload(camelContext);
+                } catch (Exception e) {
+                    LOG.warn(
+                            "Reloading of plugin {} failed, however the exception will be ignored so other plugins can be reloaded. Reason: {}",
+                            plugin.getClass().getName(), e.getMessage(), e);
+                }
+            }
+        }
+    }
+
     @Override
     protected void doStop() throws Exception {
         if (contextServicePlugins != null) {

core/camel-core/src/test/java/org/apache/camel/support/RouteWatcherReloadStrategyOnReloadTest.java

@@ -0,0 +1,169 @@
+/*
+ * 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.camel.support;
+
+import java.util.Collections;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.apache.camel.CamelContext;
+import org.apache.camel.ContextTestSupport;
+import org.apache.camel.ServiceStatus;
+import org.apache.camel.spi.ContextServiceLoaderPluginResolver;
+import org.apache.camel.spi.ContextServicePlugin;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class RouteWatcherReloadStrategyOnReloadTest extends ContextTestSupport {
+
+    @Test
+    public void testOnReloadInvokesPlugins() throws Exception {
+        AtomicInteger reloadCount = new AtomicInteger();
+
+        // Create a test plugin that tracks reload calls
+        ContextServicePlugin testPlugin = new ContextServicePlugin() {
+            @Override
+            public void load(CamelContext camelContext) {
+                // NO-OP
+            }
+
+            @Override
+            public void onReload(CamelContext camelContext) {
+                reloadCount.incrementAndGet();
+            }
+        };
+
+        // Register a custom resolver with our test plugin
+        ContextServiceLoaderPluginResolver resolver = new TestContextServiceLoaderPluginResolver(context, testPlugin);
+        context.getCamelContextExtension().addContextPlugin(ContextServiceLoaderPluginResolver.class, resolver);
+
+        RouteWatcherReloadStrategy strategy = new RouteWatcherReloadStrategy();
+        strategy.setCamelContext(context);
+
+        // Trigger route reload
+        strategy.onRouteReload(Collections.emptyList(), false);
+
+        assertEquals(1, reloadCount.get(), "onReload should have been called once on the plugin");
+
+        // Trigger another reload
+        strategy.onRouteReload(Collections.emptyList(), false);
+
+        assertEquals(2, reloadCount.get(), "onReload should have been called twice on the plugin");
+    }
+
+    @Test
+    public void testOnReloadDefaultNoOp() throws Exception {
+        // Verify the default onReload is a no-op and does not throw
+        ContextServicePlugin plugin = new ContextServicePlugin() {
+            @Override
+            public void load(CamelContext camelContext) {
+                // NO-OP
+            }
+        };
+
+        // Should not throw
+        plugin.onReload(context);
+    }
+
+    /**
+     * A simple test resolver that delegates to a single plugin.
+     */
+    private static class TestContextServiceLoaderPluginResolver implements ContextServiceLoaderPluginResolver {
+        private CamelContext camelContext;
+        private final ContextServicePlugin plugin;
+
+        TestContextServiceLoaderPluginResolver(CamelContext camelContext, ContextServicePlugin plugin) {
+            this.camelContext = camelContext;
+            this.plugin = plugin;
+        }
+
+        @Override
+        public void onReload() {
+            plugin.onReload(camelContext);
+        }
+
+        @Override
+        public void setCamelContext(CamelContext camelContext) {
+            this.camelContext = camelContext;
+        }
+
+        @Override
+        public CamelContext getCamelContext() {
+            return camelContext;
+        }
+
+        @Override
+        public void start() {
+        }
+
+        @Override
+        public void stop() {
+        }
+
+        @Override
+        public void suspend() {
+        }
+
+        @Override
+        public void resume() {
+        }
+
+        @Override
+        public void shutdown() {
+        }
+
+        @Override
+        public ServiceStatus getStatus() {
+            return ServiceStatus.Started;
+        }
+
+        @Override
+        public boolean isStarted() {
+            return true;
+        }
+
+        @Override
+        public boolean isStarting() {
+            return false;
+        }
+
+        @Override
+        public boolean isStopping() {
+            return false;
+        }
+
+        @Override
+        public boolean isStopped() {
+            return false;
+        }
+
+        @Override
+        public boolean isSuspending() {
+            return false;
+        }
+
+        @Override
+        public boolean isSuspended() {
+            return false;
+        }
+
+        @Override
+        public boolean isRunAllowed() {
+            return true;
+        }
+    }
+}

core/camel-support/src/main/java/org/apache/camel/support/RouteWatcherReloadStrategy.java

@@ -32,6 +32,7 @@
 import org.apache.camel.RuntimeCamelException;
 import org.apache.camel.ServiceStatus;
 import org.apache.camel.StartupSummaryLevel;
+import org.apache.camel.spi.ContextServiceLoaderPluginResolver;
 import org.apache.camel.spi.GroovyScriptCompiler;
 import org.apache.camel.spi.PropertiesComponent;
 import org.apache.camel.spi.PropertiesReload;
@@ -247,6 +248,13 @@ protected boolean onGroovyReload(Resource resource, boolean reloadRoutes) throws
 
     @SuppressWarnings("unchecked")
     protected void onRouteReload(Collection<Resource> resources, boolean removeEverything) {
+        // notify context service plugins before reloading routes
+        ContextServiceLoaderPluginResolver pluginResolver
+                = getCamelContext().getCamelContextExtension().getContextPlugin(ContextServiceLoaderPluginResolver.class);
+        if (pluginResolver != null) {
+            pluginResolver.onReload();
+        }
+
         // remember all existing resources
         List<Resource> sources = new ArrayList<>();
 

dsl/camel-jbang/camel-jbang-core/src/main/java/org/apache/camel/dsl/jbang/core/commands/Run.java

@@ -1000,8 +1000,18 @@ private int run() throws Exception {
         addRuntimeSpecificDependenciesFromProperties(profileProperties);
 
         // Add plugin dependencies
+        Map<String, Plugin> activePlugins = Collections.emptyMap();
         if (!skipPlugins) {
-            Set<PluginExporter> exporters = PluginHelper.getActivePlugins(getMain(), repositories).values()
+            activePlugins = PluginHelper.getActivePlugins(getMain(), repositories);
+
+            // Let plugins customize the run environment (e.g., set config directories)
+            // before plugin exporter dependencies are added, so exporters can scan the right locations
+            for (Plugin plugin : activePlugins.values()) {
+                plugin.getRunCustomizer()
+                        .ifPresent(customizer -> customizer.beforeRun(main, Collections.unmodifiableList(files)));
+            }
+
+            Set<PluginExporter> exporters = activePlugins.values()
                     .stream()
                     .map(Plugin::getExporter)
                     .filter(Optional::isPresent)

dsl/camel-jbang/camel-jbang-core/src/main/java/org/apache/camel/dsl/jbang/core/common/Plugin.java

@@ -42,4 +42,15 @@ public interface Plugin {
     default Optional<PluginExporter> getExporter() {
         return Optional.empty();
     }
+
+    /**
+     * The plugin may provide an optional run customizer that is called after the Run command has resolved file
+     * arguments and basic dependencies, but before plugin exporter dependencies are added and KameletMain.run() builds
+     * the CamelContext.
+     *
+     * @return the plugin specific run customizer implementation, otherwise empty
+     */
+    default Optional<PluginRunCustomizer> getRunCustomizer() {
+        return Optional.empty();
+    }
 }

dsl/camel-jbang/camel-jbang-core/src/main/java/org/apache/camel/dsl/jbang/core/common/PluginRunCustomizer.java

@@ -0,0 +1,40 @@
+/*
+ * 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.camel.dsl.jbang.core.common;
+
+import java.util.List;
+
+import org.apache.camel.main.KameletMain;
+
+/**
+ * Plugin hook that runs after the Run command has resolved file arguments and basic dependencies, but before plugin
+ * exporter dependencies are added and {@link KameletMain#run()} builds the CamelContext.
+ *
+ * This allows plugins to customize the environment (system properties, config directories, initial properties) based on
+ * the file arguments passed to the run command, so that plugin exporters can scan the right locations.
+ */
+public interface PluginRunCustomizer {
+
+    /**
+     * Called after the Run command has resolved file arguments and basic dependencies, but before plugin exporter
+     * dependencies are added and KameletMain.run() builds the CamelContext.
+     *
+     * @param main  the KameletMain instance (for adding initial properties)
+     * @param files the resolved file arguments passed to the run command (read-only)
+     */
+    void beforeRun(KameletMain main, List<String> files);
+}

dsl/camel-jbang/camel-jbang-core/src/test/java/org/apache/camel/dsl/jbang/core/common/PluginRunCustomizerTest.java

@@ -0,0 +1,73 @@
+/*
+ * 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.camel.dsl.jbang.core.common;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+import org.apache.camel.dsl.jbang.core.commands.CamelJBangMain;
+import org.apache.camel.main.KameletMain;
+import org.junit.jupiter.api.Test;
+import picocli.CommandLine;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class PluginRunCustomizerTest {
+
+    @Test
+    public void testPluginDefaultReturnsEmpty() {
+        Plugin plugin = (commandLine, main) -> {
+            // no-op
+        };
+
+        assertTrue(plugin.getRunCustomizer().isEmpty());
+    }
+
+    @Test
+    public void testPluginWithRunCustomizer() {
+        List<String> capturedFiles = new ArrayList<>();
+        boolean[] called = { false };
+
+        PluginRunCustomizer customizer = (main, files) -> {
+            called[0] = true;
+            capturedFiles.addAll(files);
+        };
+
+        Plugin plugin = new Plugin() {
+            @Override
+            public void customize(CommandLine commandLine, CamelJBangMain main) {
+                // no-op
+            }
+
+            @Override
+            public Optional<PluginRunCustomizer> getRunCustomizer() {
+                return Optional.of(customizer);
+            }
+        };
+
+        Optional<PluginRunCustomizer> result = plugin.getRunCustomizer();
+        assertTrue(result.isPresent());
+
+        // Simulate invoking the customizer
+        List<String> testFiles = List.of("route.yaml", "beans.xml");
+        result.get().beforeRun(new KameletMain("test"), testFiles);
+
+        assertTrue(called[0]);
+        assertEquals(testFiles, capturedFiles);
+    }
+}