org.opendaylight.bgpcep.bgp.topology.provider.AbstractTopologyBuilder Maven / Gradle / Ivy
/*
* Copyright (c) 2013 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 org.opendaylight.bgpcep.bgp.topology.provider;
import static java.util.Objects.requireNonNull;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;
import com.google.common.util.concurrent.FluentFuture;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.MoreExecutors;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import org.checkerframework.checker.lock.qual.GuardedBy;
import org.opendaylight.bgpcep.topology.TopologyReference;
import org.opendaylight.mdsal.binding.api.DataBroker;
import org.opendaylight.mdsal.binding.api.DataTreeChangeListener;
import org.opendaylight.mdsal.binding.api.DataTreeIdentifier;
import org.opendaylight.mdsal.binding.api.DataTreeModification;
import org.opendaylight.mdsal.binding.api.ReadWriteTransaction;
import org.opendaylight.mdsal.binding.api.TransactionChain;
import org.opendaylight.mdsal.binding.api.WriteTransaction;
import org.opendaylight.mdsal.common.api.CommitInfo;
import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
import org.opendaylight.protocol.bgp.rib.RibReference;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.Route;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.bgp.rib.rib.LocRib;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.rib.Tables;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev180329.rib.TablesKey;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.AddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev200120.SubsequentAddressFamily;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NetworkTopology;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.TopologyId;
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.TopologyBuilder;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.TopologyKey;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.TopologyTypes;
import org.opendaylight.yangtools.concepts.Registration;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.opendaylight.yangtools.yang.common.Empty;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public abstract class AbstractTopologyBuilder
implements DataTreeChangeListener, TopologyReference, FutureCallback {
private static final Logger LOG = LoggerFactory.getLogger(AbstractTopologyBuilder.class);
// we limit the listener reset interval to be 5 min at most
private static final long LISTENER_RESET_LIMIT_IN_MILLSEC = 5 * 60 * 1000;
private static final int LISTENER_RESET_ENFORCE_COUNTER = 3;
private final InstanceIdentifier topology;
private final RibReference locRibReference;
private final DataBroker dataProvider;
private final AddressFamily afi;
private final SubsequentAddressFamily safi;
private final TopologyKey topologyKey;
private final TopologyTypes topologyTypes;
private final long listenerResetLimitInMillsec;
private final int listenerResetEnforceCounter;
@GuardedBy("this")
private Registration listenerRegistration = null;
@GuardedBy("this")
private TransactionChain chain = null;
private final AtomicBoolean closed = new AtomicBoolean(false);
@GuardedBy("this")
@VisibleForTesting
protected long listenerScheduledRestartTime = 0;
@GuardedBy("this")
@VisibleForTesting
protected int listenerScheduledRestartEnforceCounter = 0;
protected boolean networkTopologyTransaction = true;
protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
final TopologyId topologyId, final TopologyTypes types, final AddressFamily afi,
final SubsequentAddressFamily safi, final long listenerResetLimitInMillsec,
final int listenerResetEnforceCounter) {
this.dataProvider = dataProvider;
this.locRibReference = requireNonNull(locRibReference);
topologyKey = new TopologyKey(requireNonNull(topologyId));
topologyTypes = types;
this.afi = afi;
this.safi = safi;
this.listenerResetLimitInMillsec = listenerResetLimitInMillsec;
this.listenerResetEnforceCounter = listenerResetEnforceCounter;
topology = InstanceIdentifier.builder(NetworkTopology.class)
.child(Topology.class, topologyKey)
.build();
}
protected AbstractTopologyBuilder(final DataBroker dataProvider, final RibReference locRibReference,
final TopologyId topologyId, final TopologyTypes types, final AddressFamily afi,
final SubsequentAddressFamily safi) {
this(dataProvider, locRibReference, topologyId, types, afi, safi, LISTENER_RESET_LIMIT_IN_MILLSEC,
LISTENER_RESET_ENFORCE_COUNTER);
}
public final synchronized void start() {
LOG.debug("Initiating topology builder from {} at {}. AFI={}, SAFI={}", locRibReference, topology,
afi, safi);
initTransactionChain();
initOperationalTopology();
registerDataChangeListener();
}
/**
* Register to data tree change listener.
*/
private synchronized void registerDataChangeListener() {
Preconditions.checkState(listenerRegistration == null,
"Topology Listener on topology %s has been registered before.",
this.getInstanceIdentifier());
final InstanceIdentifier tablesId = locRibReference.getInstanceIdentifier()
.child(LocRib.class).child(Tables.class, new TablesKey(afi, safi));
final DataTreeIdentifier id = DataTreeIdentifier.of(LogicalDatastoreType.OPERATIONAL,
getRouteWildcard(tablesId));
listenerRegistration = dataProvider.registerTreeChangeListener(id, this);
LOG.debug("Registered listener {} on topology {}. Timestamp={}", this, this.getInstanceIdentifier(),
listenerScheduledRestartTime);
}
/**
* Unregister to data tree change listener.
*/
private synchronized void unregisterDataChangeListener() {
if (listenerRegistration != null) {
LOG.debug("Unregistered listener {} on topology {}", this, this.getInstanceIdentifier());
listenerRegistration.close();
listenerRegistration = null;
}
}
protected abstract InstanceIdentifier getRouteWildcard(InstanceIdentifier tablesId);
protected abstract void createObject(ReadWriteTransaction trans, InstanceIdentifier id, T value);
protected abstract void removeObject(ReadWriteTransaction trans, InstanceIdentifier id, T value);
protected abstract void clearTopology();
@Override
public final InstanceIdentifier getInstanceIdentifier() {
return topology;
}
public final synchronized FluentFuture close() {
if (closed.getAndSet(true)) {
LOG.trace("Transaction chain was already closed.");
return CommitInfo.emptyFluentFuture();
}
LOG.info("Shutting down builder for {}", getInstanceIdentifier());
unregisterDataChangeListener();
final FluentFuture future = destroyOperationalTopology();
destroyTransactionChain();
return future;
}
@Override
@SuppressWarnings("checkstyle:IllegalCatch")
public synchronized void onDataTreeChanged(final List> changes) {
if (networkTopologyTransaction) {
if (closed.get()) {
LOG.trace("Transaction chain was already closed, skipping update.");
return;
}
// check if the transaction chain needed to be restarted due to a previous error
if (restartTransactionChainOnDemand()) {
LOG.debug("The data change {} is disregarded due to restart of listener {}", changes, this);
return;
}
final ReadWriteTransaction trans = chain.newReadWriteTransaction();
LOG.trace("Received data change {} event with transaction {}", changes, trans.getIdentifier());
final AtomicBoolean transactionInError = new AtomicBoolean(false);
for (final DataTreeModification change : changes) {
try {
routeChanged(change, trans);
} catch (final RuntimeException exc) {
LOG.warn("Data change {} (transaction {}) was not completely propagated to listener {}", change,
trans.getIdentifier(), this, exc);
// trans.cancel() is not supported by PingPongTransactionChain, so we just skip the problematic
// change.
// trans.commit() must be called first to unlock the current transaction chain, to make the chain
// closable so we cannot exit the #onDataTreeChanged() yet
transactionInError.set(true);
break;
}
}
trans.commit().addCallback(new FutureCallback() {
@Override
public void onSuccess(final CommitInfo result) {
// as we are enforcing trans.commit(), in some cases the transaction execution actually could be
// successfully even when an exception is captured, thus #onTransactionChainFailed() never get
// invoked. Though the transaction chain remains usable,
// the data loss will not be able to be recovered. Thus we schedule a listener restart here
if (transactionInError.get()) {
LOG.warn("Transaction {} committed successfully while exception captured. Rescheduling a"
+ " restart of listener {}", trans
.getIdentifier(), AbstractTopologyBuilder.this);
scheduleListenerRestart();
} else {
LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
}
}
@Override
public void onFailure(final Throwable throwable) {
// we do nothing but print out the log. Transaction chain restart will be done in
// #onTransactionChainFailed()
LOG.error("Failed to propagate change (transaction {}) by listener {}", trans.getIdentifier(),
AbstractTopologyBuilder.this, throwable);
}
}, MoreExecutors.directExecutor());
} else {
for (final DataTreeModification change : changes) {
routeChanged(change, null);
}
}
}
@VisibleForTesting
protected void routeChanged(final DataTreeModification change, final ReadWriteTransaction trans) {
final var root = change.getRootNode();
switch (root.modificationType()) {
case DELETE:
removeObject(trans, change.getRootPath().path(), root.dataBefore());
break;
case SUBTREE_MODIFIED:
case WRITE:
final var before = root.dataBefore();
if (before != null) {
removeObject(trans, change.getRootPath().path(), before);
}
createObject(trans, change.getRootPath().path(), root.dataAfter());
break;
default:
throw new IllegalArgumentException("Unhandled modification type " + root.modificationType());
}
}
private synchronized void initOperationalTopology() {
requireNonNull(chain, "A valid transaction chain must be provided.");
final WriteTransaction trans = chain.newWriteOnlyTransaction();
trans.mergeParentStructurePut(LogicalDatastoreType.OPERATIONAL, topology,
new TopologyBuilder()
.withKey(topologyKey)
.setServerProvided(Boolean.TRUE)
.setTopologyTypes(topologyTypes)
.setLink(Map.of())
.setNode(Map.of())
.build());
trans.commit().addCallback(new FutureCallback() {
@Override
public void onSuccess(final CommitInfo result) {
LOG.trace("Transaction {} committed successfully", trans.getIdentifier());
}
@Override
public void onFailure(final Throwable throwable) {
LOG.error("Failed to initialize topology {} (transaction {}) by listener {}",
AbstractTopologyBuilder.this.topology,
trans.getIdentifier(), AbstractTopologyBuilder.this, throwable);
}
}, MoreExecutors.directExecutor());
}
/**
* Destroy the current operational topology data. Note a valid transaction must be provided.
*/
private synchronized FluentFuture destroyOperationalTopology() {
requireNonNull(chain, "A valid transaction chain must be provided.");
final WriteTransaction trans = chain.newWriteOnlyTransaction();
trans.delete(LogicalDatastoreType.OPERATIONAL, getInstanceIdentifier());
final FluentFuture future = trans.commit();
future.addCallback(new FutureCallback() {
@Override
public void onSuccess(final CommitInfo result) {
LOG.trace("Operational topology removed {}", AbstractTopologyBuilder.this.topology);
}
@Override
public void onFailure(final Throwable throwable) {
LOG.error("Unable to reset operational topology {} (transaction {})",
AbstractTopologyBuilder.this.topology, trans.getIdentifier(), throwable);
}
}, MoreExecutors.directExecutor());
clearTopology();
return future;
}
/**
* Reset a transaction chain by closing the current chain and starting a new one.
*/
private synchronized void initTransactionChain() {
LOG.debug("Initializing transaction chain for topology {}", this);
Preconditions.checkState(chain == null,
"Transaction chain has to be closed before being initialized");
chain = dataProvider.createMergingTransactionChain();
chain.addCallback(this);
}
/**
* Destroy the current transaction chain.
*/
private synchronized void destroyTransactionChain() {
if (chain != null) {
LOG.debug("Destroy transaction chain for topology {}", this);
// we cannot close the transaction chain, as it will close the AbstractDOMForwardedTransactionFactory
// and the transaction factory cannot be reopen even if we recreate the transaction chain
// so we abandon the chain directly
// FIXME we want to close the transaction chain gracefully once the PingPongTransactionChain get improved
// and the above problem get resolved.
// try {
// this.chain.close();
// } catch (Exception e) {
// // the close() may not succeed when the transaction chain is locked
// LOG.error("Unable to close transaction chain {} for topology builder {}", this.chain,
// getInstanceIdentifier());
// }
chain = null;
}
}
/**
* Reset the data change listener to its initial status.
* By resetting the listener we will be able to recover all the data lost before
*/
@VisibleForTesting
protected synchronized void resetListener() {
requireNonNull(listenerRegistration, "Listener on topology " + this + " hasn't been initialized.");
LOG.debug("Resetting data change listener for topology builder {}", getInstanceIdentifier());
// unregister current listener to prevent incoming data tree change first
unregisterDataChangeListener();
// create new transaction chain to reset the chain status
resetTransactionChain();
// reset the operational topology data so that we can have clean status
destroyOperationalTopology();
initOperationalTopology();
// re-register the data change listener to reset the operational topology
// we are expecting to receive all the pre-exist route change on the next onDataTreeChanged() call
registerDataChangeListener();
}
/**
* Reset the transaction chain only so that the PingPong transaction chain will become usable again.
* However, there will be data loss if we do not apply the previous failed transaction again
*/
@VisibleForTesting
protected synchronized void resetTransactionChain() {
LOG.debug("Resetting transaction chain for topology builder {}", getInstanceIdentifier());
destroyTransactionChain();
initTransactionChain();
}
/**
* There are a few reasons we want to schedule a listener restart in a delayed manner:
* 1. we should avoid restarting the listener as when the topology is big, there might be huge overhead
* rebuilding the whole linkstate topology again and again
* 2. the #onTransactionChainFailed() normally get invoked after a delay. During that time gap, more
* data changes might still be pushed to #onDataTreeChanged(). And because #onTransactionChainFailed()
* is not invoked yet, listener restart/transaction chain restart is not done. Thus the new changes
* will still cause error and another #onTransactionChainFailed() might be invoked later. The listener
* will be restarted again in that case, which is unexpected. Restarting of transaction chain only introduce
* little overhead and it's okay to be restarted within a small time window.
* Note: when the listener is restarted, we can disregard all the incoming data changes before the restart is
* done, as after the listener unregister/reregister, the first #onDataTreeChanged() call will contain the a
* complete set of existing changes
*
* @return if the listener get restarted, return true; otherwise false
*/
@VisibleForTesting
protected synchronized boolean restartTransactionChainOnDemand() {
if (listenerScheduledRestartTime > 0) {
// when the #this.listenerScheduledRestartTime timer timed out we can reset the listener,
// otherwise we should only reset the transaction chain
if (System.currentTimeMillis() > listenerScheduledRestartTime) {
// reset the the restart timer
listenerScheduledRestartTime = 0;
listenerScheduledRestartEnforceCounter = 0;
resetListener();
return true;
}
resetTransactionChain();
}
return false;
}
@VisibleForTesting
protected synchronized void scheduleListenerRestart() {
if (0 == listenerScheduledRestartTime) {
listenerScheduledRestartTime = System.currentTimeMillis() + listenerResetLimitInMillsec;
} else if (System.currentTimeMillis() > listenerScheduledRestartTime
&& ++listenerScheduledRestartEnforceCounter < listenerResetEnforceCounter) {
// if the transaction failure happens again, we will delay the listener restart up to
// #LISTENER_RESET_LIMIT_IN_MILLSEC times
listenerScheduledRestartTime += listenerResetLimitInMillsec;
}
LOG.debug("A listener restart was scheduled at {} (current system time is {})",
listenerScheduledRestartTime, System.currentTimeMillis());
}
@Override
public final synchronized void onFailure(final Throwable cause) {
LOG.error("Topology builder for {} failed", getInstanceIdentifier(), cause);
scheduleListenerRestart();
restartTransactionChainOnDemand();
}
@Override
public final void onSuccess(final Empty value) {
LOG.info("Topology builder for {} shut down", getInstanceIdentifier());
}
}
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