| /* |
| * 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.aries.rsa.topologymanager.importer; |
| |
| import java.util.Set; |
| import java.util.concurrent.CopyOnWriteArraySet; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.LinkedBlockingQueue; |
| import java.util.concurrent.ThreadPoolExecutor; |
| import java.util.concurrent.TimeUnit; |
| import java.util.stream.Stream; |
| |
| import org.osgi.framework.BundleContext; |
| import org.osgi.service.remoteserviceadmin.EndpointDescription; |
| import org.osgi.service.remoteserviceadmin.EndpointEvent; |
| import org.osgi.service.remoteserviceadmin.EndpointEventListener; |
| import org.osgi.service.remoteserviceadmin.ImportReference; |
| import org.osgi.service.remoteserviceadmin.ImportRegistration; |
| import org.osgi.service.remoteserviceadmin.RemoteServiceAdmin; |
| import org.osgi.service.remoteserviceadmin.RemoteServiceAdminEvent; |
| import org.osgi.service.remoteserviceadmin.RemoteServiceAdminListener; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Listens for remote endpoints using the EndpointListener. The scope of this listener is managed by |
| * the EndpointListenerManager. |
| * Manages local creation and destruction of service imports using the available RemoteServiceAdmin services. |
| */ |
| public class TopologyManagerImport implements EndpointEventListener, RemoteServiceAdminListener { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(TopologyManagerImport.class); |
| |
| private final ExecutorService execService; |
| private final BundleContext bctx; |
| private final Set<RemoteServiceAdmin> rsaSet; |
| private volatile boolean stopped; |
| |
| /** |
| * List of Endpoints by matched filter that were reported by the EndpointListener and can be imported |
| */ |
| private final MultiMap<String, EndpointDescription> importPossibilities = new MultiMap<>(); |
| |
| /** |
| * List of already imported Endpoints by their matched filter |
| */ |
| private final MultiMap<String, ImportRegistration> importedServices = new MultiMap<>(); |
| |
| public TopologyManagerImport(BundleContext bc) { |
| this.rsaSet = new CopyOnWriteArraySet<>(); |
| bctx = bc; |
| execService = new ThreadPoolExecutor(5, 10, 50, TimeUnit.SECONDS, new LinkedBlockingQueue<>(), new NamedThreadFactory(getClass())); |
| } |
| |
| public void start() { |
| stopped = false; |
| bctx.registerService(RemoteServiceAdminListener.class, this, null); |
| } |
| |
| public void stop() { |
| stopped = true; |
| execService.shutdown(); |
| try { |
| execService.awaitTermination(10, TimeUnit.SECONDS); |
| } catch (InterruptedException e) { |
| LOG.info("Interrupted while waiting for {} to terminate", execService); |
| Thread.currentThread().interrupt(); |
| } |
| // close all imports |
| importPossibilities.clear(); |
| importedServices.allValues().forEach(this::unimportRegistration); |
| } |
| |
| public void add(RemoteServiceAdmin rsa) { |
| rsaSet.add(rsa); |
| importPossibilities.keySet().forEach(this::synchronizeImportsAsync); |
| } |
| |
| public void remove(RemoteServiceAdmin rsa) { |
| rsaSet.remove(rsa); |
| } |
| |
| @Override |
| public void remoteAdminEvent(RemoteServiceAdminEvent event) { |
| ImportReference ref = event.getImportReference(); |
| if (event.getType() == RemoteServiceAdminEvent.IMPORT_UNREGISTRATION && ref != null) { |
| importedServices.allValues().stream() |
| .filter(ir -> ref.equals(ir.getImportReference())) |
| .forEach(this::unimportRegistration); |
| } |
| } |
| |
| private void synchronizeImportsAsync(final String filter) { |
| LOG.debug("Import of a service for filter {} was queued", filter); |
| if (!rsaSet.isEmpty()) { |
| execService.execute(() -> synchronizeImports(filter)); |
| } |
| } |
| |
| /** |
| * Synchronizes the actual imports with the possible imports for the given filter, |
| * i.e. unimports previously imported endpoints that are no longer possible, |
| * and imports new possible endpoints that are not already imported. |
| * |
| * TODO but optional: if the service is already imported and the endpoint is still |
| * in the list of possible imports check if a "better" endpoint is now in the list |
| * |
| * @param filter the filter whose endpoints are synchronized |
| */ |
| private void synchronizeImports(final String filter) { |
| try { |
| ImportDiff diff = new ImportDiff(importPossibilities.get(filter), importedServices.get(filter)); |
| diff.getRemoved() |
| .forEach(this::unimportRegistration); |
| diff.getAdded() |
| .flatMap(this::importService) |
| .forEach(ir -> importedServices.put(filter, ir)); |
| } catch (Exception e) { |
| LOG.error(e.getMessage(), e); |
| } |
| // Notify EndpointListeners? NO! |
| } |
| |
| /** |
| * Tries to import the service with each rsa until one import is successful. |
| * |
| * @param filter the filter that matched the endpoint |
| * @param endpoint endpoint to import |
| * @return |
| */ |
| private Stream<ImportRegistration> importService(EndpointDescription endpoint) { |
| for (RemoteServiceAdmin rsa : rsaSet) { |
| ImportRegistration ir = rsa.importService(endpoint); |
| if (ir != null) { |
| if (ir.getException() == null) { |
| LOG.debug("Service import was successful {}", ir); |
| return Stream.of(ir); |
| } else { |
| LOG.info("Error importing service " + endpoint, ir.getException()); |
| } |
| } |
| } |
| return Stream.empty(); |
| } |
| |
| private void unimportRegistration(ImportRegistration reg) { |
| importedServices.remove(reg); |
| reg.close(); |
| } |
| |
| @Override |
| public void endpointChanged(EndpointEvent event, String filter) { |
| if (stopped) { |
| return; |
| } |
| EndpointDescription endpoint = event.getEndpoint(); |
| LOG.debug("Endpoint event received type {}, filter {}, endpoint {}", event.getType(), filter, endpoint); |
| switch (event.getType()) { |
| case EndpointEvent.ADDED: |
| importPossibilities.put(filter, endpoint); |
| break; |
| case EndpointEvent.REMOVED: |
| case EndpointEvent.MODIFIED_ENDMATCH: |
| importPossibilities.remove(filter, endpoint); |
| break; |
| case EndpointEvent.MODIFIED: |
| importPossibilities.remove(filter, endpoint); |
| importPossibilities.put(filter, endpoint); |
| break; |
| } |
| synchronizeImportsAsync(filter); |
| } |
| |
| } |