1 files changed, 159 insertions, 0 deletions
diff --git a/vbd/impl/src/main/java/io/fd/honeycomb/vbd/impl/TopologyMonitor.java b/vbd/impl/src/main/java/io/fd/honeycomb/vbd/impl/TopologyMonitor.java
new file mode 100644
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+++ b/vbd/impl/src/main/java/io/fd/honeycomb/vbd/impl/TopologyMonitor.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2016 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package io.fd.honeycomb.vbd.impl;
+
+import com.google.common.base.Preconditions;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Map.Entry;
+import javax.annotation.concurrent.GuardedBy;
+import org.opendaylight.controller.md.sal.binding.api.BindingTransactionChain;
+import org.opendaylight.controller.md.sal.binding.api.DataBroker;
+import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
+import org.opendaylight.controller.md.sal.binding.api.DataTreeChangeListener;
+import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
+import org.opendaylight.controller.md.sal.common.api.data.AsyncTransaction;
+import org.opendaylight.controller.md.sal.common.api.data.TransactionChain;
+import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vbridge.topology.rev160129.network.topology.topology.topology.types.VbridgeTopology;
+import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.Topology;
+import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyKey;
+import org.opendaylight.yangtools.yang.binding.KeyedInstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Class responsible for monitoring /network-topology/topology and activating a {@link BridgeDomain} when a particular
+ * topology is marked as a bridge domain.
+ */
+final class TopologyMonitor implements DataTreeChangeListener<VbridgeTopology>, AutoCloseable {
+    private static final Logger LOG = LoggerFactory.getLogger(TopologyMonitor.class);
+
+    @GuardedBy("this")
+    private final Map<TopologyKey, BridgeDomain> domains = new HashMap<>();
+    private final DataBroker dataBroker;
+
+    TopologyMonitor(final DataBroker dataBroker) {
+        this.dataBroker = Preconditions.checkNotNull(dataBroker);
+    }
+
+    @Override
+    public synchronized void onDataTreeChanged(final Collection<DataTreeModification<VbridgeTopology>> changes) {
+        for (DataTreeModification<VbridgeTopology> c : changes) {
+            @SuppressWarnings("unchecked")
+            final KeyedInstanceIdentifier<Topology, TopologyKey> topology =
+                    (KeyedInstanceIdentifier<Topology, TopologyKey>) c.getRootPath().getRootIdentifier()
+                    .firstIdentifierOf(Topology.class);
+
+            Preconditions.checkArgument(!topology.isWildcarded(), "Wildcard topology %s is not supported", topology);
+
+            final DataObjectModification<VbridgeTopology> mod = c.getRootNode();
+            switch (mod.getModificationType()) {
+                case DELETE:
+                    LOG.debug("Topology {} removed", topology);
+                    stopDomain(topology);
+                    break;
+                case WRITE:
+                    LOG.debug("Topology {} added", topology);
+                    startDomain(topology);
+                    break;
+                default:
+                    LOG.warn("Ignoring unhandled modification type {}", mod.getModificationType());
+                    break;
+            }
+        }
+    }
+
+    private synchronized void completeDomain(final KeyedInstanceIdentifier<Topology, TopologyKey> topology) {
+        LOG.debug("Bridge domain for {} completed operation", topology);
+        domains.remove(topology);
+
+        synchronized (domains) {
+            domains.notify();
+        }
+    }
+
+    private synchronized void restartDomain(final KeyedInstanceIdentifier<Topology, TopologyKey> topology) {
+        final BridgeDomain prev = domains.remove(topology);
+        if (prev == null) {
+            LOG.warn("No domain for {}, not restarting", topology);
+            return;
+        }
+
+        prev.forceStop();
+        startDomain(topology);
+    }
+
+    @GuardedBy("this")
+    private void startDomain(final KeyedInstanceIdentifier<Topology, TopologyKey> topology) {
+        final BridgeDomain prev = domains.get(topology.getKey());
+        if (prev != null) {
+            LOG.warn("Bridge domain {} for {} already started", prev, topology);
+            return;
+        }
+
+        LOG.debug("Starting bridge domain for {}", topology);
+
+        final BindingTransactionChain chain = dataBroker.createTransactionChain(new TransactionChainListener() {
+            @Override
+            public void onTransactionChainSuccessful(final TransactionChain<?, ?> chain) {
+                completeDomain(topology);
+            }
+
+            @Override
+            public void onTransactionChainFailed(final TransactionChain<?, ?> chain,
+                    final AsyncTransaction<?, ?> transaction, final Throwable cause) {
+                LOG.warn("Bridge domain for {} failed, restarting it", cause);
+                restartDomain(topology);
+            }
+        });
+
+        final BridgeDomain domain = BridgeDomain.create(dataBroker, topology, chain);
+        domains.put(topology.getKey(), domain);
+
+        LOG.debug("Bridge domain {} for {} started", domain, topology);
+    }
+
+    @GuardedBy("this")
+    private void stopDomain(final KeyedInstanceIdentifier<Topology, TopologyKey> topology) {
+        final BridgeDomain domain = domains.remove(topology.getKey());
+        if (domain == null) {
+            LOG.warn("Bridge domain for {} not present", topology);
+            return;
+        }
+
+        domain.stop();
+    }
+
+    @Override
+    public synchronized void close() {
+        LOG.debug("Topology monitor {} shut down started", this);
+
+        for (Entry<TopologyKey, BridgeDomain> e : domains.entrySet()) {
+            LOG.debug("Shutting down bridge domain {} (key {})", e.getValue(), e.getKey());
+            e.getValue().stop();
+        }
+
+        while (!domains.isEmpty()) {
+            LOG.debug("Waiting for domains for {} to complete", domains.keySet());
+            synchronized (domains) {
+                try {
+                    domains.wait();
+                } catch (InterruptedException e) {
+                    LOG.warn("Interrupted while waiting for domain shutdown, {} have not completed yet",
+                        domains.keySet(), e);
+                    break;
+                }
+            }
+        }
+
+        LOG.debug("Topology monitor {} shut down completed", this);
+    }
+}