2 * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
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
8 package org.opendaylight.bgpcep.bgp.topology.provider;
10 import com.google.common.annotations.VisibleForTesting;
11 import com.google.common.base.Preconditions;
12 import com.google.common.util.concurrent.CheckedFuture;
13 import com.google.common.util.concurrent.FutureCallback;
14 import com.google.common.util.concurrent.Futures;
15 import com.google.common.util.concurrent.ListenableFuture;
16 import java.util.Collection;
17 import java.util.Collections;
18 import java.util.concurrent.atomic.AtomicBoolean;
19 import javax.annotation.concurrent.GuardedBy;
20 import org.opendaylight.bgpcep.topology.TopologyReference;
21 import org.opendaylight.controller.md.sal.binding.api.BindingTransactionChain;
22 import org.opendaylight.controller.md.sal.binding.api.ClusteredDataTreeChangeListener;
23 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
24 import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
25 import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
26 import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
27 import org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction;
28 import org.opendaylight.controller.md.sal.binding.api.WriteTransaction;
29 import org.opendaylight.controller.md.sal.common.api.data.AsyncTransaction;
30 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
31 import org.opendaylight.controller.md.sal.common.api.data.TransactionChain;
32 import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener;
33 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
34 import org.opendaylight.protocol.bgp.rib.RibReference;
35 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.Route;
36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.LocRib;
37 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.Tables;
38 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
39 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
40 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily;
41 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NetworkTopology;
42 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.TopologyId;
43 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.Topology;
44 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyBuilder;
45 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyKey;
46 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.TopologyTypes;
47 import org.opendaylight.yangtools.concepts.ListenerRegistration;
48 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
49 import org.slf4j.Logger;
50 import org.slf4j.LoggerFactory;
52 public abstract class AbstractTopologyBuilder<T extends Route> implements ClusteredDataTreeChangeListener<T>,
53 TopologyReference, TransactionChainListener {
54 private static final Logger LOG = LoggerFactory.getLogger(AbstractTopologyBuilder.class);
55 // we limit the listener reset interval to be 5 min at most
56 private static final long LISTENER_RESET_LIMIT_IN_MILLSEC = 5 * 60 * 1000;
57 private static final int LISTENER_RESET_ENFORCE_COUNTER = 3;
58 private final InstanceIdentifier<Topology> topology;
59 private final RibReference locRibReference;
60 private final DataBroker dataProvider;
61 private final Class<? extends AddressFamily> afi;
62 private final Class<? extends SubsequentAddressFamily> safi;
63 private final TopologyKey topologyKey;
64 private final TopologyTypes topologyTypes;
65 private final long listenerResetLimitInMillsec;
66 private final int listenerResetEnforceCounter;
69 private ListenerRegistration<AbstractTopologyBuilder<T>> listenerRegistration = null;
71 private BindingTransactionChain chain = null;
73 private boolean closed = false;
76 protected long listenerScheduledRestartTime = 0;
79 protected int listenerScheduledRestartEnforceCounter = 0;
81 protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
82 final TopologyId topologyId, final TopologyTypes types, final Class<? extends AddressFamily> afi,
83 final Class<? extends SubsequentAddressFamily> safi, final long listenerResetLimitInMillsec,
84 final int listenerResetEnforceCounter) {
85 this.dataProvider = dataProvider;
86 this.locRibReference = Preconditions.checkNotNull(locRibReference);
87 this.topologyKey = new TopologyKey(Preconditions.checkNotNull(topologyId));
88 this.topologyTypes = types;
91 this.listenerResetLimitInMillsec = listenerResetLimitInMillsec;
92 this.listenerResetEnforceCounter = listenerResetEnforceCounter;
93 this.topology = InstanceIdentifier.builder(NetworkTopology.class).child(Topology.class, this.topologyKey).build();
96 protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
97 final TopologyId topologyId, final TopologyTypes types, final Class<? extends AddressFamily> afi,
98 final Class<? extends SubsequentAddressFamily> safi) {
99 this(dataProvider, locRibReference, topologyId, types, afi, safi, LISTENER_RESET_LIMIT_IN_MILLSEC, LISTENER_RESET_ENFORCE_COUNTER);
102 public final synchronized void start() {
103 LOG.debug("Initiating topology builder from {} at {}. AFI={}, SAFI={}", this.locRibReference, this.topology, this.afi, this.safi);
104 initTransactionChain();
105 initOperationalTopology();
106 registerDataChangeListener();
110 public final InstanceIdentifier<Tables> tableInstanceIdentifier(final Class<? extends AddressFamily> afi,
111 final Class<? extends SubsequentAddressFamily> safi) {
112 return this.locRibReference.getInstanceIdentifier().builder().child(LocRib.class).child(Tables.class, new TablesKey(afi, safi)).build();
116 * Register to data tree change listener
118 private synchronized void registerDataChangeListener() {
119 Preconditions.checkState(this.listenerRegistration == null, "Topology Listener on topology %s has been registered before.", this.getInstanceIdentifier());
120 final InstanceIdentifier<Tables> tablesId = this.locRibReference.getInstanceIdentifier().child(LocRib.class).child(Tables.class, new TablesKey(this.afi, this.safi));
121 final DataTreeIdentifier<T> id = new DataTreeIdentifier<>(LogicalDatastoreType.OPERATIONAL, getRouteWildcard(tablesId));
123 this.listenerRegistration = this.dataProvider.registerDataTreeChangeListener(id, this);
124 LOG.debug("Registered listener {} on topology {}. Timestamp={}", this, this.getInstanceIdentifier(), this.listenerScheduledRestartTime);
128 * Unregister to data tree change listener
130 private final synchronized void unregisterDataChangeListener() {
131 if (this.listenerRegistration != null) {
132 LOG.debug("Unregistered listener {} on topology {}", this, this.getInstanceIdentifier());
133 this.listenerRegistration.close();
134 this.listenerRegistration = null;
138 protected abstract InstanceIdentifier<T> getRouteWildcard(InstanceIdentifier<Tables> tablesId);
140 protected abstract void createObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
142 protected abstract void removeObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
144 protected abstract void clearTopology();
147 public final InstanceIdentifier<Topology> getInstanceIdentifier() {
148 return this.topology;
151 public final synchronized ListenableFuture<Void> close() {
153 LOG.trace("Transaction chain was already closed.");
154 Futures.immediateFuture(null);
157 LOG.info("Shutting down builder for {}", getInstanceIdentifier());
158 unregisterDataChangeListener();
159 final ListenableFuture<Void> future = destroyOperationalTopology();
160 destroyTransactionChain();
165 public synchronized void onDataTreeChanged(final Collection<DataTreeModification<T>> changes) {
167 LOG.trace("Transaction chain was already closed, skipping update.");
170 // check if the transaction chain needed to be restarted due to a previous error
171 if (restartTransactionChainOnDemand()) {
172 LOG.debug("The data change {} is disregarded due to restart of listener {}", changes, this);
175 final ReadWriteTransaction trans = this.chain.newReadWriteTransaction();
176 LOG.debug("Received data change {} event with transaction {}", changes, trans.getIdentifier());
177 final AtomicBoolean transactionInError = new AtomicBoolean(false);
178 for (final DataTreeModification<T> change : changes) {
180 routeChanged(change, trans);
181 } catch (final RuntimeException e) {
182 LOG.warn("Data change {} (transaction {}) was not completely propagated to listener {}", change, trans.getIdentifier(), this, e);
183 // trans.cancel() is not supported by PingPongTransactionChain, so we just skip the problematic change
184 // trans.submit() must be called first to unlock the current transaction chain, to make the chain closable
185 // so we cannot exit the #onDataTreeChanged() yet
186 transactionInError.set(true);
190 Futures.addCallback(trans.submit(), new FutureCallback<Void>() {
192 public void onSuccess(final Void result) {
193 // as we are enforcing trans.submit(), in some cases the transaction execution actually could be successfully even when an
194 // exception is captured, thus #onTransactionChainFailed() never get invoked. Though the transaction chain remains usable,
195 // the data loss will not be able to be recovered. Thus we schedule a listener restart here
196 if (transactionInError.get()) {
197 LOG.warn("Transaction {} committed successfully while exception captured. Rescheduling a restart of listener {}", trans
198 .getIdentifier(), AbstractTopologyBuilder.this);
199 scheduleListenerRestart();
201 LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
206 public void onFailure(final Throwable t) {
207 // we do nothing but print out the log. Transaction chain restart will be done in #onTransactionChainFailed()
208 LOG.error("Failed to propagate change (transaction {}) by listener {}", trans.getIdentifier(), AbstractTopologyBuilder.this, t);
214 protected void routeChanged(final DataTreeModification<T> change, final ReadWriteTransaction trans) {
215 final DataObjectModification<T> root = change.getRootNode();
216 switch (root.getModificationType()) {
218 removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
220 case SUBTREE_MODIFIED:
222 if (root.getDataBefore() != null) {
223 removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
225 createObject(trans, change.getRootPath().getRootIdentifier(), root.getDataAfter());
228 throw new IllegalArgumentException("Unhandled modification type " + root.getModificationType());
232 private synchronized void initOperationalTopology() {
233 Preconditions.checkNotNull(this.chain, "A valid transaction chain must be provided.");
234 final WriteTransaction trans = this.chain.newWriteOnlyTransaction();
235 trans.put(LogicalDatastoreType.OPERATIONAL, this.topology,
236 new TopologyBuilder().setKey(this.topologyKey).setServerProvided(Boolean.TRUE).setTopologyTypes(this.topologyTypes)
237 .setLink(Collections.emptyList()).setNode(Collections.emptyList()).build(), true);
238 Futures.addCallback(trans.submit(), new FutureCallback<Void>() {
240 public void onSuccess(final Void result) {
241 LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
245 public void onFailure(final Throwable t) {
246 LOG.error("Failed to initialize topology {} (transaction {}) by listener {}", AbstractTopologyBuilder.this.topology,
247 trans.getIdentifier(), AbstractTopologyBuilder.this, t);
253 * Destroy the current operational topology data. Note a valid transaction must be provided
254 * @throws TransactionCommitFailedException
256 private synchronized ListenableFuture<Void> destroyOperationalTopology() {
257 Preconditions.checkNotNull(this.chain, "A valid transaction chain must be provided.");
258 final WriteTransaction trans = this.chain.newWriteOnlyTransaction();
259 trans.delete(LogicalDatastoreType.OPERATIONAL, getInstanceIdentifier());
260 final CheckedFuture<Void, TransactionCommitFailedException> future = trans.submit();
261 Futures.addCallback(future, new FutureCallback<Void>() {
263 public void onSuccess(final Void result) {
264 LOG.trace("Operational topology removed {}", AbstractTopologyBuilder.this.topology);
268 public void onFailure(final Throwable t) {
269 LOG.error("Unable to reset operational topology {} (transaction {})",
270 AbstractTopologyBuilder.this.topology, trans.getIdentifier(), t);
278 * Reset a transaction chain by closing the current chain and starting a new one
280 private synchronized void initTransactionChain() {
281 LOG.debug("Initializing transaction chain for topology {}", this);
282 Preconditions.checkState(this.chain == null, "Transaction chain has to be closed before being initialized");
283 this.chain = this.dataProvider.createTransactionChain(this);
287 * Destroy the current transaction chain
289 private synchronized void destroyTransactionChain() {
290 if (this.chain != null) {
291 LOG.debug("Destroy transaction chain for topology {}", this);
292 // we cannot close the transaction chain, as it will close the AbstractDOMForwardedTransactionFactory
293 // and the transaction factory cannot be reopen even if we recreate the transaction chain
294 // so we abandon the chain directly
295 // FIXME we want to close the transaction chain gracefully once the PingPongTransactionChain get improved
296 // and the above problem get resolved.
298 // this.chain.close();
299 // } catch (Exception e) {
300 // // the close() may not succeed when the transaction chain is locked
301 // LOG.error("Unable to close transaction chain {} for topology builder {}", this.chain, getInstanceIdentifier());
308 * Reset the data change listener to its initial status
309 * By resetting the listener we will be able to recover all the data lost before
312 protected synchronized void resetListener() {
313 Preconditions.checkNotNull(this.listenerRegistration, "Listener on topology %s hasn't been initialized.", this);
314 LOG.debug("Resetting data change listener for topology builder {}", getInstanceIdentifier());
315 // unregister current listener to prevent incoming data tree change first
316 unregisterDataChangeListener();
317 // create new transaction chain to reset the chain status
318 resetTransactionChain();
319 // reset the operational topology data so that we can have clean status
320 destroyOperationalTopology();
321 initOperationalTopology();
322 // re-register the data change listener to reset the operational topology
323 // we are expecting to receive all the pre-exist route change on the next onDataTreeChanged() call
324 registerDataChangeListener();
328 * Reset the transaction chain only so that the PingPong transaction chain will become usable again.
329 * However, there will be data loss if we do not apply the previous failed transaction again
332 protected synchronized void resetTransactionChain() {
333 LOG.debug("Resetting transaction chain for topology builder {}", getInstanceIdentifier());
334 destroyTransactionChain();
335 initTransactionChain();
339 * There are a few reasons we want to schedule a listener restart in a delayed manner:
340 * 1. we should avoid restarting the listener as when the topology is big, there might be huge overhead
341 * rebuilding the whole linkstate topology again and again
342 * 2. the #onTransactionChainFailed() normally get invoked after a delay. During that time gap, more
343 * data changes might still be pushed to #onDataTreeChanged(). And because #onTransactionChainFailed()
344 * is not invoked yet, listener restart/transaction chain restart is not done. Thus the new changes
345 * will still cause error and another #onTransactionChainFailed() might be invoked later. The listener
346 * will be restarted again in that case, which is unexpected. Restarting of transaction chain only introduce
347 * little overhead and it's okay to be restarted within a small time window
349 * Note: when the listener is restarted, we can disregard all the incoming data changes before the restart is
350 * done, as after the listener unregister/reregister, the first #onDataTreeChanged() call will contain the a
351 * complete set of existing changes
353 * @return if the listener get restarted, return true; otherwise false
356 protected synchronized boolean restartTransactionChainOnDemand() {
357 if (this.listenerScheduledRestartTime > 0) {
358 // when the #this.listenerScheduledRestartTime timer timed out we can reset the listener, otherwise we should only reset the transaction chain
359 if (System.currentTimeMillis() > this.listenerScheduledRestartTime) {
360 // reset the the restart timer
361 this.listenerScheduledRestartTime = 0;
362 this.listenerScheduledRestartEnforceCounter = 0;
366 resetTransactionChain();
373 protected synchronized void scheduleListenerRestart() {
374 if (0 == this.listenerScheduledRestartTime) {
375 this.listenerScheduledRestartTime = System.currentTimeMillis() + this.listenerResetLimitInMillsec;
376 } else if (System.currentTimeMillis() > this.listenerScheduledRestartTime
377 && ++this.listenerScheduledRestartEnforceCounter < this.listenerResetEnforceCounter) {
378 // if the transaction failure happens again, we will delay the listener restart up to #LISTENER_RESET_LIMIT_IN_MILLSEC times
379 this.listenerScheduledRestartTime += this.listenerResetLimitInMillsec;
381 LOG.debug("A listener restart was scheduled at {} (current system time is {})", this.listenerScheduledRestartTime, System.currentTimeMillis());
385 public final synchronized void onTransactionChainFailed(final TransactionChain<?, ?> chain, final AsyncTransaction<?, ?> transaction, final Throwable cause) {
386 LOG.error("Topology builder for {} failed in transaction {}.", getInstanceIdentifier(), transaction != null ? transaction.getIdentifier() : null, cause);
387 scheduleListenerRestart();
388 restartTransactionChainOnDemand();
392 public final void onTransactionChainSuccessful(final TransactionChain<?, ?> chain) {
393 LOG.info("Topology builder for {} shut down", getInstanceIdentifier());