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 static java.util.Objects.requireNonNull;
12 import com.google.common.annotations.VisibleForTesting;
13 import com.google.common.base.Preconditions;
14 import com.google.common.util.concurrent.FutureCallback;
15 import com.google.common.util.concurrent.Futures;
16 import com.google.common.util.concurrent.ListenableFuture;
17 import com.google.common.util.concurrent.MoreExecutors;
18 import java.util.Collection;
19 import java.util.Collections;
20 import java.util.concurrent.atomic.AtomicBoolean;
21 import javax.annotation.concurrent.GuardedBy;
22 import org.opendaylight.bgpcep.topology.TopologyReference;
23 import org.opendaylight.controller.md.sal.binding.api.BindingTransactionChain;
24 import org.opendaylight.controller.md.sal.binding.api.ClusteredDataTreeChangeListener;
25 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
26 import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
27 import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
28 import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
29 import org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction;
30 import org.opendaylight.controller.md.sal.binding.api.WriteTransaction;
31 import org.opendaylight.controller.md.sal.common.api.data.AsyncTransaction;
32 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
33 import org.opendaylight.controller.md.sal.common.api.data.TransactionChain;
34 import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener;
35 import org.opendaylight.protocol.bgp.rib.RibReference;
36 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.Route;
37 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.bgp.rib.rib.LocRib;
38 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.rib.Tables;
39 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev171207.rib.TablesKey;
40 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
41 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily;
42 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NetworkTopology;
43 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.TopologyId;
44 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.Topology;
45 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyBuilder;
46 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyKey;
47 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.TopologyTypes;
48 import org.opendaylight.yangtools.concepts.ListenerRegistration;
49 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
50 import org.slf4j.Logger;
51 import org.slf4j.LoggerFactory;
53 public abstract class AbstractTopologyBuilder<T extends Route> implements ClusteredDataTreeChangeListener<T>,
54 TopologyReference, TransactionChainListener {
55 private static final Logger LOG = LoggerFactory.getLogger(AbstractTopologyBuilder.class);
56 // we limit the listener reset interval to be 5 min at most
57 private static final long LISTENER_RESET_LIMIT_IN_MILLSEC = 5 * 60 * 1000;
58 private static final int LISTENER_RESET_ENFORCE_COUNTER = 3;
59 private final InstanceIdentifier<Topology> topology;
60 private final RibReference locRibReference;
61 private final DataBroker dataProvider;
62 private final Class<? extends AddressFamily> afi;
63 private final Class<? extends SubsequentAddressFamily> safi;
64 private final TopologyKey topologyKey;
65 private final TopologyTypes topologyTypes;
66 private final long listenerResetLimitInMillsec;
67 private final int listenerResetEnforceCounter;
70 private ListenerRegistration<AbstractTopologyBuilder<T>> listenerRegistration = null;
72 private BindingTransactionChain chain = null;
74 private boolean closed = false;
77 protected long listenerScheduledRestartTime = 0;
80 protected int listenerScheduledRestartEnforceCounter = 0;
82 protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
83 final TopologyId topologyId, final TopologyTypes types, final Class<? extends AddressFamily> afi,
84 final Class<? extends SubsequentAddressFamily> safi, final long listenerResetLimitInMillsec,
85 final int listenerResetEnforceCounter) {
86 this.dataProvider = dataProvider;
87 this.locRibReference = requireNonNull(locRibReference);
88 this.topologyKey = new TopologyKey(requireNonNull(topologyId));
89 this.topologyTypes = types;
92 this.listenerResetLimitInMillsec = listenerResetLimitInMillsec;
93 this.listenerResetEnforceCounter = listenerResetEnforceCounter;
94 this.topology = InstanceIdentifier.builder(NetworkTopology.class)
95 .child(Topology.class, this.topologyKey).build();
98 protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
99 final TopologyId topologyId, final TopologyTypes types, final Class<? extends AddressFamily> afi,
100 final Class<? extends SubsequentAddressFamily> safi) {
101 this(dataProvider, locRibReference, topologyId, types, afi, safi, LISTENER_RESET_LIMIT_IN_MILLSEC,
102 LISTENER_RESET_ENFORCE_COUNTER);
105 public final synchronized void start() {
106 LOG.debug("Initiating topology builder from {} at {}. AFI={}, SAFI={}", this.locRibReference, this.topology,
107 this.afi, this.safi);
108 initTransactionChain();
109 initOperationalTopology();
110 registerDataChangeListener();
114 * Register to data tree change listener.
116 private synchronized void registerDataChangeListener() {
117 Preconditions.checkState(this.listenerRegistration == null,
118 "Topology Listener on topology %s has been registered before.",
119 this.getInstanceIdentifier());
120 final InstanceIdentifier<Tables> tablesId = this.locRibReference.getInstanceIdentifier()
121 .child(LocRib.class).child(Tables.class, new TablesKey(this.afi, this.safi));
122 final DataTreeIdentifier<T> id = new DataTreeIdentifier<>(LogicalDatastoreType.OPERATIONAL,
123 getRouteWildcard(tablesId));
125 this.listenerRegistration = this.dataProvider.registerDataTreeChangeListener(id, this);
126 LOG.debug("Registered listener {} on topology {}. Timestamp={}", this, this.getInstanceIdentifier(),
127 this.listenerScheduledRestartTime);
131 * Unregister to data tree change listener.
133 private synchronized void unregisterDataChangeListener() {
134 if (this.listenerRegistration != null) {
135 LOG.debug("Unregistered listener {} on topology {}", this, this.getInstanceIdentifier());
136 this.listenerRegistration.close();
137 this.listenerRegistration = null;
141 protected abstract InstanceIdentifier<T> getRouteWildcard(InstanceIdentifier<Tables> tablesId);
143 protected abstract void createObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
145 protected abstract void removeObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
147 protected abstract void clearTopology();
150 public final InstanceIdentifier<Topology> getInstanceIdentifier() {
151 return this.topology;
154 public final synchronized ListenableFuture<Void> close() {
156 LOG.trace("Transaction chain was already closed.");
157 Futures.immediateFuture(null);
160 LOG.info("Shutting down builder for {}", getInstanceIdentifier());
161 unregisterDataChangeListener();
162 final ListenableFuture<Void> future = destroyOperationalTopology();
163 destroyTransactionChain();
168 @SuppressWarnings("checkstyle:IllegalCatch")
169 public synchronized void onDataTreeChanged(final Collection<DataTreeModification<T>> changes) {
171 LOG.trace("Transaction chain was already closed, skipping update.");
174 // check if the transaction chain needed to be restarted due to a previous error
175 if (restartTransactionChainOnDemand()) {
176 LOG.debug("The data change {} is disregarded due to restart of listener {}", changes, this);
179 final ReadWriteTransaction trans = this.chain.newReadWriteTransaction();
180 LOG.trace("Received data change {} event with transaction {}", changes, trans.getIdentifier());
181 final AtomicBoolean transactionInError = new AtomicBoolean(false);
182 for (final DataTreeModification<T> change : changes) {
184 routeChanged(change, trans);
185 } catch (final RuntimeException exc) {
186 LOG.warn("Data change {} (transaction {}) was not completely propagated to listener {}", change,
187 trans.getIdentifier(), this, exc);
188 // trans.cancel() is not supported by PingPongTransactionChain, so we just skip the problematic change
189 // trans.submit() must be called first to unlock the current transaction chain, to make the chain
190 // closable so we cannot exit the #onDataTreeChanged() yet
191 transactionInError.set(true);
195 Futures.addCallback(trans.submit(), new FutureCallback<Void>() {
197 public void onSuccess(final Void result) {
198 // as we are enforcing trans.submit(), in some cases the transaction execution actually could be
199 // successfully even when an exception is captured, thus #onTransactionChainFailed() never get invoked.
200 // Though the transaction chain remains usable,
201 // the data loss will not be able to be recovered. Thus we schedule a listener restart here
202 if (transactionInError.get()) {
203 LOG.warn("Transaction {} committed successfully while exception captured. Rescheduling a restart"
204 + " of listener {}", trans
205 .getIdentifier(), AbstractTopologyBuilder.this);
206 scheduleListenerRestart();
208 LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
213 public void onFailure(final Throwable throwable) {
214 // we do nothing but print out the log. Transaction chain restart will be done in
215 // #onTransactionChainFailed()
216 LOG.error("Failed to propagate change (transaction {}) by listener {}", trans.getIdentifier(),
217 AbstractTopologyBuilder.this, throwable);
219 }, MoreExecutors.directExecutor());
223 protected void routeChanged(final DataTreeModification<T> change, final ReadWriteTransaction trans) {
224 final DataObjectModification<T> root = change.getRootNode();
225 switch (root.getModificationType()) {
227 removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
229 case SUBTREE_MODIFIED:
231 if (root.getDataBefore() != null) {
232 removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
234 createObject(trans, change.getRootPath().getRootIdentifier(), root.getDataAfter());
237 throw new IllegalArgumentException("Unhandled modification type " + root.getModificationType());
241 private synchronized void initOperationalTopology() {
242 requireNonNull(this.chain, "A valid transaction chain must be provided.");
243 final WriteTransaction trans = this.chain.newWriteOnlyTransaction();
244 trans.put(LogicalDatastoreType.OPERATIONAL, this.topology,
245 new TopologyBuilder().setKey(this.topologyKey).setServerProvided(Boolean.TRUE)
246 .setTopologyTypes(this.topologyTypes)
247 .setLink(Collections.emptyList()).setNode(Collections.emptyList()).build(), true);
248 Futures.addCallback(trans.submit(), new FutureCallback<Void>() {
250 public void onSuccess(final Void result) {
251 LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
255 public void onFailure(final Throwable throwable) {
256 LOG.error("Failed to initialize topology {} (transaction {}) by listener {}",
257 AbstractTopologyBuilder.this.topology,
258 trans.getIdentifier(), AbstractTopologyBuilder.this, throwable);
260 }, MoreExecutors.directExecutor());
264 * Destroy the current operational topology data. Note a valid transaction must be provided.
266 private synchronized ListenableFuture<Void> destroyOperationalTopology() {
267 requireNonNull(this.chain, "A valid transaction chain must be provided.");
268 final WriteTransaction trans = this.chain.newWriteOnlyTransaction();
269 trans.delete(LogicalDatastoreType.OPERATIONAL, getInstanceIdentifier());
270 final ListenableFuture<Void> future = trans.submit();
271 Futures.addCallback(future, new FutureCallback<Void>() {
273 public void onSuccess(final Void result) {
274 LOG.trace("Operational topology removed {}", AbstractTopologyBuilder.this.topology);
278 public void onFailure(final Throwable throwable) {
279 LOG.error("Unable to reset operational topology {} (transaction {})",
280 AbstractTopologyBuilder.this.topology, trans.getIdentifier(), throwable);
282 }, MoreExecutors.directExecutor());
288 * Reset a transaction chain by closing the current chain and starting a new one.
290 private synchronized void initTransactionChain() {
291 LOG.debug("Initializing transaction chain for topology {}", this);
292 Preconditions.checkState(this.chain == null,
293 "Transaction chain has to be closed before being initialized");
294 this.chain = this.dataProvider.createTransactionChain(this);
298 * Destroy the current transaction chain.
300 private synchronized void destroyTransactionChain() {
301 if (this.chain != null) {
302 LOG.debug("Destroy transaction chain for topology {}", this);
303 // we cannot close the transaction chain, as it will close the AbstractDOMForwardedTransactionFactory
304 // and the transaction factory cannot be reopen even if we recreate the transaction chain
305 // so we abandon the chain directly
306 // FIXME we want to close the transaction chain gracefully once the PingPongTransactionChain get improved
307 // and the above problem get resolved.
309 // this.chain.close();
310 // } catch (Exception e) {
311 // // the close() may not succeed when the transaction chain is locked
312 // LOG.error("Unable to close transaction chain {} for topology builder {}", this.chain,
313 // getInstanceIdentifier());
320 * Reset the data change listener to its initial status.
321 * By resetting the listener we will be able to recover all the data lost before
324 protected synchronized void resetListener() {
325 requireNonNull(this.listenerRegistration, "Listener on topology " + this + " hasn't been initialized.");
326 LOG.debug("Resetting data change listener for topology builder {}", getInstanceIdentifier());
327 // unregister current listener to prevent incoming data tree change first
328 unregisterDataChangeListener();
329 // create new transaction chain to reset the chain status
330 resetTransactionChain();
331 // reset the operational topology data so that we can have clean status
332 destroyOperationalTopology();
333 initOperationalTopology();
334 // re-register the data change listener to reset the operational topology
335 // we are expecting to receive all the pre-exist route change on the next onDataTreeChanged() call
336 registerDataChangeListener();
340 * Reset the transaction chain only so that the PingPong transaction chain will become usable again.
341 * However, there will be data loss if we do not apply the previous failed transaction again
344 protected synchronized void resetTransactionChain() {
345 LOG.debug("Resetting transaction chain for topology builder {}", getInstanceIdentifier());
346 destroyTransactionChain();
347 initTransactionChain();
351 * There are a few reasons we want to schedule a listener restart in a delayed manner:
352 * 1. we should avoid restarting the listener as when the topology is big, there might be huge overhead
353 * rebuilding the whole linkstate topology again and again
354 * 2. the #onTransactionChainFailed() normally get invoked after a delay. During that time gap, more
355 * data changes might still be pushed to #onDataTreeChanged(). And because #onTransactionChainFailed()
356 * is not invoked yet, listener restart/transaction chain restart is not done. Thus the new changes
357 * will still cause error and another #onTransactionChainFailed() might be invoked later. The listener
358 * will be restarted again in that case, which is unexpected. Restarting of transaction chain only introduce
359 * little overhead and it's okay to be restarted within a small time window.
360 * Note: when the listener is restarted, we can disregard all the incoming data changes before the restart is
361 * done, as after the listener unregister/reregister, the first #onDataTreeChanged() call will contain the a
362 * complete set of existing changes
364 * @return if the listener get restarted, return true; otherwise false
367 protected synchronized boolean restartTransactionChainOnDemand() {
368 if (this.listenerScheduledRestartTime > 0) {
369 // when the #this.listenerScheduledRestartTime timer timed out we can reset the listener,
370 // otherwise we should only reset the transaction chain
371 if (System.currentTimeMillis() > this.listenerScheduledRestartTime) {
372 // reset the the restart timer
373 this.listenerScheduledRestartTime = 0;
374 this.listenerScheduledRestartEnforceCounter = 0;
379 resetTransactionChain();
385 protected synchronized void scheduleListenerRestart() {
386 if (0 == this.listenerScheduledRestartTime) {
387 this.listenerScheduledRestartTime = System.currentTimeMillis() + this.listenerResetLimitInMillsec;
388 } else if (System.currentTimeMillis() > this.listenerScheduledRestartTime
389 && ++this.listenerScheduledRestartEnforceCounter < this.listenerResetEnforceCounter) {
390 // if the transaction failure happens again, we will delay the listener restart up to
391 // #LISTENER_RESET_LIMIT_IN_MILLSEC times
392 this.listenerScheduledRestartTime += this.listenerResetLimitInMillsec;
394 LOG.debug("A listener restart was scheduled at {} (current system time is {})",
395 this.listenerScheduledRestartTime, System.currentTimeMillis());
399 public final synchronized void onTransactionChainFailed(final TransactionChain<?, ?> chain,
400 final AsyncTransaction<?, ?> transaction, final Throwable cause) {
401 LOG.error("Topology builder for {} failed in transaction {}.", getInstanceIdentifier(),
402 transaction != null ? transaction.getIdentifier() : null, cause);
403 scheduleListenerRestart();
404 restartTransactionChainOnDemand();
408 public final void onTransactionChainSuccessful(final TransactionChain<?, ?> chain) {
409 LOG.info("Topology builder for {} shut down", getInstanceIdentifier());