BUG-8327: GlobalBundleScanningSchemaServiceImpl should be a proxy
[controller.git] / opendaylight / md-sal / sal-schema-service / src / main / java / org / opendaylight / controller / sal / schema / service / impl / GlobalBundleScanningSchemaServiceImpl.java
index 32a6291e5fd2f4162c186f5b1812359af4fb860d..4a4ae3b82acf9fbe5fbcf21b207f8e2ba6435c62 100644 (file)
  */
 package org.opendaylight.controller.sal.schema.service.impl;
 
-import static com.google.common.base.Preconditions.checkState;
-import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.Iterables;
 import com.google.common.util.concurrent.CheckedFuture;
-import java.net.URL;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Enumeration;
-import java.util.List;
+import com.google.common.util.concurrent.Futures;
+import java.util.HashSet;
+import java.util.Set;
 import javax.annotation.concurrent.GuardedBy;
 import org.opendaylight.controller.sal.core.api.model.SchemaService;
 import org.opendaylight.controller.sal.core.api.model.YangTextSourceProvider;
+import org.opendaylight.mdsal.dom.api.DOMSchemaService;
+import org.opendaylight.mdsal.dom.api.DOMYangTextSourceProvider;
+import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
 import org.opendaylight.yangtools.concepts.ListenerRegistration;
-import org.opendaylight.yangtools.concepts.Registration;
-import org.opendaylight.yangtools.util.ListenerRegistry;
 import org.opendaylight.yangtools.yang.model.api.Module;
 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
 import org.opendaylight.yangtools.yang.model.api.SchemaContextProvider;
+import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceException;
 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
-import org.opendaylight.yangtools.yang.parser.repo.YangTextSchemaContextResolver;
-import org.osgi.framework.Bundle;
-import org.osgi.framework.BundleContext;
-import org.osgi.framework.BundleEvent;
-import org.osgi.framework.ServiceReference;
-import org.osgi.util.tracker.BundleTracker;
-import org.osgi.util.tracker.BundleTrackerCustomizer;
-import org.osgi.util.tracker.ServiceTracker;
-import org.osgi.util.tracker.ServiceTrackerCustomizer;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
-public class GlobalBundleScanningSchemaServiceImpl implements SchemaContextProvider, SchemaService,
-        ServiceTrackerCustomizer<SchemaContextListener, SchemaContextListener>, YangTextSourceProvider, AutoCloseable {
-    private static final Logger LOG = LoggerFactory.getLogger(GlobalBundleScanningSchemaServiceImpl.class);
-    private static final long FRAMEWORK_BUNDLE_ID = 0;
+public final class GlobalBundleScanningSchemaServiceImpl implements SchemaContextProvider, SchemaService,
+        YangTextSourceProvider, AutoCloseable {
 
-    @GuardedBy(value = "lock")
-    private final ListenerRegistry<SchemaContextListener> listeners = new ListenerRegistry<>();
-    private final YangTextSchemaContextResolver contextResolver = YangTextSchemaContextResolver.create("global-bundle");
-    private final BundleScanner scanner = new BundleScanner();
+    @GuardedBy("lock")
+    private final Set<ListenerRegistration<?>> listeners = new HashSet<>();
     private final Object lock = new Object();
-    private final BundleContext context;
-
-    private ServiceTracker<SchemaContextListener, SchemaContextListener> listenerTracker;
-    private BundleTracker<Iterable<Registration>> bundleTracker;
-    private boolean starting = true;
-
-    private volatile boolean stopping;
-
-    private GlobalBundleScanningSchemaServiceImpl(final BundleContext context) {
-        this.context = Preconditions.checkNotNull(context);
-    }
+    private final DOMSchemaService schemaService;
+    private final DOMYangTextSourceProvider yangProvider;
 
-    public static GlobalBundleScanningSchemaServiceImpl createInstance(final BundleContext ctx) {
-        GlobalBundleScanningSchemaServiceImpl instance = new GlobalBundleScanningSchemaServiceImpl(ctx);
-        instance.start();
-        return instance;
+    private GlobalBundleScanningSchemaServiceImpl(final DOMSchemaService schemaService) {
+        this.schemaService = Preconditions.checkNotNull(schemaService);
+        this.yangProvider = (DOMYangTextSourceProvider) schemaService.getSupportedExtensions()
+                .get(DOMYangTextSourceProvider.class);
     }
 
-    public BundleContext getContext() {
-        return context;
-    }
-
-    private void start() {
-        checkState(context != null);
-        LOG.debug("start() starting");
-
-        listenerTracker = new ServiceTracker<>(context, SchemaContextListener.class, this);
-        bundleTracker = new BundleTracker<>(context, Bundle.RESOLVED | Bundle.STARTING |
-                Bundle.STOPPING | Bundle.ACTIVE, scanner);
-
-        synchronized (lock) {
-            bundleTracker.open();
-
-            LOG.debug("BundleTracker.open() complete");
-            if (Iterables.size(listeners.getListeners()) > 0) {
-                tryToUpdateSchemaContext();
-            }
-        }
-
-        listenerTracker.open();
-        starting = false;
-
-        LOG.debug("start() complete");
+    public static GlobalBundleScanningSchemaServiceImpl createInstance(final DOMSchemaService schemaService) {
+        return new GlobalBundleScanningSchemaServiceImpl(schemaService);
     }
 
     @Override
     public SchemaContext getSchemaContext() {
-        return getGlobalContext();
+        return schemaService.getGlobalContext();
     }
 
     @Override
     public SchemaContext getGlobalContext() {
-        return contextResolver.getSchemaContext().orNull();
+        return schemaService.getGlobalContext();
     }
 
     @Override
@@ -127,168 +76,44 @@ public class GlobalBundleScanningSchemaServiceImpl implements SchemaContextProvi
     public ListenerRegistration<SchemaContextListener> registerSchemaContextListener(
             final SchemaContextListener listener) {
         synchronized (lock) {
-            Optional<SchemaContext> potentialCtx = contextResolver.getSchemaContext();
-            if(potentialCtx.isPresent()) {
-                listener.onGlobalContextUpdated(potentialCtx.get());
-            }
-            return listeners.register(listener);
+            final ListenerRegistration<SchemaContextListener> reg = schemaService.registerSchemaContextListener(
+                listener);
+
+            final ListenerRegistration<SchemaContextListener> ret =
+                    new AbstractListenerRegistration<SchemaContextListener>(listener) {
+                @Override
+                protected void removeRegistration() {
+                    synchronized (lock) {
+                        listeners.remove(this);
+                    }
+                    reg.close();
+                }
+            };
+
+            listeners.add(ret);
+            return ret;
         }
     }
 
     @Override
     public void close() {
         synchronized (lock) {
-            stopping = true;
-            if (bundleTracker != null) {
-                bundleTracker.close();
-                bundleTracker = null;
-            }
-            if (listenerTracker != null) {
-                listenerTracker.close();
-                listenerTracker = null;
-            }
-
-            for (ListenerRegistration<SchemaContextListener> l : listeners.getListeners()) {
+            for (ListenerRegistration<?> l : listeners) {
                 l.close();
             }
+            listeners.clear();
         }
     }
 
-    @GuardedBy("lock")
-    private void notifyListeners(final SchemaContext snapshot) {
-        Object[] services = listenerTracker.getServices();
-        for (ListenerRegistration<SchemaContextListener> listener : listeners) {
-            try {
-                listener.getInstance().onGlobalContextUpdated(snapshot);
-            } catch (Exception e) {
-                LOG.error("Exception occured during invoking listener", e);
-            }
-        }
-        if (services != null) {
-            for (Object rawListener : services) {
-                final SchemaContextListener listener = (SchemaContextListener) rawListener;
-                try {
-                    listener.onGlobalContextUpdated(snapshot);
-                } catch (Exception e) {
-                    LOG.error("Exception occured during invoking listener {}", listener, e);
-                }
-            }
-        }
-    }
-
+    @SuppressWarnings("unchecked")
     @Override
     public CheckedFuture<YangTextSchemaSource, SchemaSourceException> getSource(
             final SourceIdentifier sourceIdentifier) {
-        return contextResolver.getSource(sourceIdentifier);
-    }
-
-    private class BundleScanner implements BundleTrackerCustomizer<Iterable<Registration>> {
-        @Override
-        public Iterable<Registration> addingBundle(final Bundle bundle, final BundleEvent event) {
-            if (bundle.getBundleId() == FRAMEWORK_BUNDLE_ID) {
-                return Collections.emptyList();
-            }
-
-            final Enumeration<URL> enumeration = bundle.findEntries("META-INF/yang", "*.yang", false);
-            if (enumeration == null) {
-                return Collections.emptyList();
-            }
-
-            final List<Registration> urls = new ArrayList<>();
-            while (enumeration.hasMoreElements()) {
-                final URL u = enumeration.nextElement();
-                try {
-                    urls.add(contextResolver.registerSource(u));
-                    LOG.debug("Registered {}", u);
-                } catch (Exception e) {
-                    LOG.warn("Failed to register {}, ignoring it", e);
-                }
-            }
-
-            if (!urls.isEmpty()) {
-                LOG.debug("Loaded {} new URLs from bundle {}, attempting to rebuild schema context",
-                        urls.size(), bundle.getSymbolicName());
-                tryToUpdateSchemaContext();
-            }
-
-            return ImmutableList.copyOf(urls);
-        }
-
-        @Override
-        public void modifiedBundle(final Bundle bundle, final BundleEvent event, final Iterable<Registration> object) {
-            if (bundle.getBundleId() == FRAMEWORK_BUNDLE_ID) {
-                LOG.debug("Framework bundle {} got event {}", bundle, event.getType());
-                if ((event.getType() & BundleEvent.STOPPING) != 0) {
-                    LOG.info("OSGi framework is being stopped, halting bundle scanning");
-                    stopping = true;
-                }
-            }
-        }
-
-        /**
-         * If removing YANG files makes yang store inconsistent, method
-         * {@link #getYangStoreSnapshot()} will throw exception. There is no
-         * rollback.
-         */
-        @Override
-        public void removedBundle(final Bundle bundle, final BundleEvent event, final Iterable<Registration> urls) {
-            for (Registration url : urls) {
-                try {
-                    url.close();
-                } catch (Exception e) {
-                    LOG.warn("Failed do unregister URL {}, proceeding", url, e);
-                }
-            }
-
-            int numUrls = Iterables.size(urls);
-            if(numUrls > 0 ) {
-                if(LOG.isDebugEnabled()) {
-                    LOG.debug("removedBundle: {}, state: {}, # urls: {}", bundle.getSymbolicName(), bundle.getState(),
-                        numUrls);
-                }
-
-                tryToUpdateSchemaContext();
-            }
+        if (yangProvider == null) {
+            return Futures.immediateFailedCheckedFuture(new MissingSchemaSourceException(
+                "Source provider is not available", sourceIdentifier));
         }
-    }
 
-    @Override
-    public SchemaContextListener addingService(final ServiceReference<SchemaContextListener> reference) {
-
-        SchemaContextListener listener = context.getService(reference);
-        SchemaContext _ctxContext = getGlobalContext();
-        if (getContext() != null && _ctxContext != null) {
-            listener.onGlobalContextUpdated(_ctxContext);
-        }
-        return listener;
-    }
-
-    public void tryToUpdateSchemaContext() {
-        if (starting || stopping) {
-            return;
-        }
-
-        synchronized (lock) {
-            Optional<SchemaContext> schema = contextResolver.getSchemaContext();
-            if (schema.isPresent()) {
-                if (LOG.isDebugEnabled()) {
-                    LOG.debug("Got new SchemaContext: # of modules {}", schema.get().getAllModuleIdentifiers().size());
-                }
-
-                notifyListeners(schema.get());
-            }
-        }
-    }
-
-    @Override
-    public void modifiedService(final ServiceReference<SchemaContextListener> reference,
-            final SchemaContextListener service) {
-        // NOOP
-    }
-
-    @Override
-    public void removedService(final ServiceReference<SchemaContextListener> reference,
-            final SchemaContextListener service) {
-        context.ungetService(reference);
+        return (CheckedFuture<YangTextSchemaSource, SchemaSourceException>) yangProvider.getSource(sourceIdentifier);
     }
 }