opendaylight/blueprint/src/main/java/org/opendaylight/controller/blueprint/BlueprintBundleTracker.java

   1 /*
   2  * Copyright (c) 2016 Brocade Communications Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.blueprint;
   9
  10 import java.util.Collections;
  11 import java.util.Dictionary;
  12 import java.util.Enumeration;
  13 import java.util.Hashtable;
  14 import java.util.List;
  15 import org.apache.aries.blueprint.services.BlueprintExtenderService;
  16 import org.osgi.framework.Bundle;
  17 import org.osgi.framework.BundleActivator;
  18 import org.osgi.framework.BundleContext;
  19 import org.osgi.framework.BundleEvent;
  20 import org.osgi.framework.ServiceReference;
  21 import org.osgi.framework.ServiceRegistration;
  22 import org.osgi.service.blueprint.container.EventConstants;
  23 import org.osgi.service.event.Event;
  24 import org.osgi.service.event.EventHandler;
  25 import org.osgi.util.tracker.BundleTracker;
  26 import org.osgi.util.tracker.BundleTrackerCustomizer;
  27 import org.osgi.util.tracker.ServiceTracker;
  28 import org.osgi.util.tracker.ServiceTrackerCustomizer;
  29 import org.slf4j.Logger;
  30 import org.slf4j.LoggerFactory;
  31
  32 /**
  33  * This class is created in bundle activation and scans ACTIVE bundles for blueprint XML files located under
  34  * the well-known org/opendaylight/blueprint/ path and deploys the XML files via the Aries
  35  * BlueprintExtenderService. This path differs from the standard OSGI-INF/blueprint path to allow for
  36  * controlled deployment of blueprint containers in an orderly manner.
  37  *
  38  * @author Thomas Pantelis
  39  */
  40 public class BlueprintBundleTracker implements BundleActivator, BundleTrackerCustomizer<Bundle>, EventHandler {
  41     private static final Logger LOG = LoggerFactory.getLogger(BlueprintBundleTracker.class);
  42     private static final String BLUEPRINT_FILE_PATH = "org/opendaylight/blueprint/";
  43     private static final String BLUEPRINT_FLE_PATTERN = "*.xml";
  44
  45     private ServiceTracker<BlueprintExtenderService, BlueprintExtenderService> serviceTracker;
  46     private BundleTracker<Bundle> bundleTracker;
  47     private volatile BlueprintExtenderService blueprintExtenderService;
  48     private ServiceRegistration<?> eventHandlerReg;
  49
  50     /**
  51      * Implemented from BundleActivator.
  52      */
  53     @Override
  54     public void start(BundleContext context) {
  55         LOG.info("Starting {}", getClass().getSimpleName());
  56
  57         // Register EventHandler for blueprint events
  58
  59         Dictionary<String, Object> props = new Hashtable<>();
  60         props.put(org.osgi.service.event.EventConstants.EVENT_TOPIC, EventConstants.TOPIC_CREATED);
  61         eventHandlerReg = context.registerService(EventHandler.class.getName(), this, props);
  62
  63         bundleTracker = new BundleTracker<>(context, Bundle.ACTIVE, this);
  64
  65         serviceTracker = new ServiceTracker<>(context, BlueprintExtenderService.class.getName(),
  66                 new ServiceTrackerCustomizer<BlueprintExtenderService, BlueprintExtenderService>() {
  67                     @Override
  68                     public BlueprintExtenderService addingService(
  69                             ServiceReference<BlueprintExtenderService> reference) {
  70                         blueprintExtenderService = reference.getBundle().getBundleContext().getService(reference);
  71                         bundleTracker.open();
  72
  73                         LOG.debug("Got BlueprintExtenderService");
  74
  75                         return blueprintExtenderService;
  76                     }
  77
  78                     @Override
  79                     public void modifiedService(ServiceReference<BlueprintExtenderService> reference,
  80                             BlueprintExtenderService service) {
  81                     }
  82
  83                     @Override
  84                     public void removedService(ServiceReference<BlueprintExtenderService> reference,
  85                             BlueprintExtenderService service) {
  86                     }
  87                 });
  88         serviceTracker.open();
  89     }
  90
  91     /**
  92      * Implemented from BundleActivator.
  93      */
  94     @Override
  95     public void stop(BundleContext context) {
  96         bundleTracker.close();
  97         serviceTracker.close();
  98         eventHandlerReg.unregister();
  99     }
 100
 101     /**
 102      * Implemented from BundleActivator.
 103      */
 104     @Override
 105     public Bundle addingBundle(Bundle bundle, BundleEvent event) {
 106         modifiedBundle(bundle, event, bundle);
 107         return bundle;
 108     }
 109
 110     /**
 111      * Implemented from BundleActivator.
 112      */
 113     @Override
 114     public void modifiedBundle(Bundle bundle, BundleEvent event, Bundle object) {
 115         if(bundle.getState() == Bundle.ACTIVE) {
 116             List<Object> paths = findBlueprintPaths(bundle);
 117
 118             if(!paths.isEmpty()) {
 119                 LOG.info("Creating blueprint container for bundle {} with paths {}", bundle, paths);
 120
 121                 blueprintExtenderService.createContainer(bundle, paths);
 122             }
 123         }
 124     }
 125
 126     /**
 127      * Implemented from BundleActivator.
 128      */
 129     @Override
 130     public void removedBundle(Bundle bundle, BundleEvent event, Bundle object) {
 131         // BlueprintExtenderService will handle this.
 132     }
 133
 134     /**
 135      * Implemented from EventHandler to listen for blueprint events.
 136      *
 137      * @param event
 138      */
 139     @Override
 140     public void handleEvent(Event event) {
 141         if(EventConstants.TOPIC_CREATED.equals(event.getTopic())) {
 142             LOG.info("Blueprint container for bundle {} was successfully created",
 143                     event.getProperty(EventConstants.BUNDLE));
 144         }
 145     }
 146
 147     @SuppressWarnings({ "rawtypes", "unchecked" })
 148     static List<Object> findBlueprintPaths(Bundle bundle) {
 149         Enumeration<?> e = bundle.findEntries(BLUEPRINT_FILE_PATH, BLUEPRINT_FLE_PATTERN, false);
 150         if(e == null) {
 151             return Collections.emptyList();
 152         } else {
 153             return Collections.list((Enumeration)e);
 154         }
 155     }
 156 }