*/
package org.opendaylight.bgpcep.bgp.topology.provider;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
-import java.util.concurrent.ExecutionException;
+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.controller.md.sal.common.api.TransactionStatus;
-import org.opendaylight.controller.md.sal.common.api.data.DataChangeEvent;
-import org.opendaylight.controller.md.sal.common.api.data.DataModification;
-import org.opendaylight.controller.sal.binding.api.data.DataChangeListener;
-import org.opendaylight.controller.sal.binding.api.data.DataModificationTransaction;
-import org.opendaylight.controller.sal.binding.api.data.DataProviderService;
+import org.opendaylight.mdsal.binding.api.ClusteredDataTreeChangeListener;
+import org.opendaylight.mdsal.binding.api.DataBroker;
+import org.opendaylight.mdsal.binding.api.DataObjectModification;
+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.rev130925.Route;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.bgp.rib.rib.LocRib;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.Tables;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.rib.rev130925.rib.TablesKey;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily;
+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.yang.binding.DataObject;
+import org.opendaylight.yangtools.concepts.Registration;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
-import org.opendaylight.yangtools.yang.common.RpcResult;
+import org.opendaylight.yangtools.yang.common.Empty;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-import com.google.common.base.Preconditions;
-import com.google.common.util.concurrent.FutureCallback;
-import com.google.common.util.concurrent.Futures;
-import com.google.common.util.concurrent.JdkFutureAdapters;
-
-public abstract class AbstractTopologyBuilder<T extends Route> implements AutoCloseable, DataChangeListener, LocRIBListener,
-TopologyReference {
- private static final Logger LOG = LoggerFactory.getLogger(AbstractTopologyBuilder.class);
- private final RibReference locRibReference;
- private final InstanceIdentifier<Topology> topology;
- private final DataProviderService dataProvider;
- private final Class<T> idClass;
-
- protected AbstractTopologyBuilder(final DataProviderService dataProvider, final RibReference locRibReference, final TopologyId topologyId, final TopologyTypes types, final Class<T> idClass) {
- this.dataProvider = Preconditions.checkNotNull(dataProvider);
- this.locRibReference = Preconditions.checkNotNull(locRibReference);
- this.idClass = Preconditions.checkNotNull(idClass);
-
- final TopologyKey tk = new TopologyKey(Preconditions.checkNotNull(topologyId));
- this.topology = InstanceIdentifier.builder(NetworkTopology.class).child(Topology.class, tk).toInstance();
-
- LOG.debug("Initiating topology builder from {} at {}", locRibReference, topology);
-
- DataModificationTransaction t = dataProvider.beginTransaction();
- Object o = t.readOperationalData(topology);
- Preconditions.checkState(o == null, "Data provider conflict detected on object {}", topology);
-
- t.putOperationalData(topology, new TopologyBuilder().setKey(tk).setServerProvided(Boolean.TRUE).setTopologyTypes(types).build());
- Futures.addCallback(JdkFutureAdapters.listenInPoolThread(t.commit()), new FutureCallback<RpcResult<TransactionStatus>>() {
- @Override
- public void onSuccess(final RpcResult<TransactionStatus> result) {
- LOG.trace("Change committed successfully");
- }
-
- @Override
- public void onFailure(final Throwable t) {
- LOG.error("Failed to initiate topology {} by listener {}", topology, AbstractTopologyBuilder.this, t);
- }
- });
- }
-
- public final InstanceIdentifier<Tables> tableInstanceIdentifier(final Class<? extends AddressFamily> afi, final Class<? extends SubsequentAddressFamily> safi) {
- return InstanceIdentifier.builder(locRibReference.getInstanceIdentifier()).child(LocRib.class).child(Tables.class, new TablesKey(afi, safi)).toInstance();
- }
-
- protected abstract void createObject(DataModification<InstanceIdentifier<?>, DataObject> trans, InstanceIdentifier<T> id, T value);
-
- protected abstract void removeObject(DataModification<InstanceIdentifier<?>, DataObject> trans, InstanceIdentifier<T> id, T value);
-
- public final DataProviderService getDataProvider() {
- return this.dataProvider;
- }
-
- @Override
- public final InstanceIdentifier<Topology> getInstanceIdentifier() {
- return this.topology;
- }
-
- private void addIdentifier(final InstanceIdentifier<?> i, final String set, final Set<InstanceIdentifier<T>> out) {
- final InstanceIdentifier<T> id = i.firstIdentifierOf(this.idClass);
- if (id != null) {
- out.add(id);
- } else {
- LOG.info("Identifier {} in {} set does not contain listening class {}, ignoring it", i, set, this.idClass);
- }
- }
-
- @Override
- public final void onLocRIBChange(final DataModification<InstanceIdentifier<?>, DataObject> trans,
- final DataChangeEvent<InstanceIdentifier<?>, DataObject> event) {
- LOG.debug("Received data change {} event with transaction {}", event, trans);
-
- final Set<InstanceIdentifier<T>> ids = new HashSet<>();
- for (final InstanceIdentifier<?> i : event.getRemovedOperationalData()) {
- addIdentifier(i, "remove", ids);
- }
- for (final InstanceIdentifier<?> i : event.getUpdatedOperationalData().keySet()) {
- addIdentifier(i, "update", ids);
- }
- for (final InstanceIdentifier<?> i : event.getCreatedOperationalData().keySet()) {
- addIdentifier(i, "create", ids);
- }
-
- final Map<InstanceIdentifier<?>, DataObject> o = event.getOriginalOperationalData();
- final Map<InstanceIdentifier<?>, DataObject> n = event.getUpdatedOperationalData();
- for (final InstanceIdentifier<T> i : ids) {
- final T oldValue = this.idClass.cast(o.get(i));
- final T newValue = this.idClass.cast(n.get(i));
-
- LOG.debug("Updating object {} value {} -> {}", i, oldValue, newValue);
- if (oldValue != null) {
- removeObject(trans, i, oldValue);
- }
- if (newValue != null) {
- createObject(trans, i, newValue);
- }
- }
-
- Futures.addCallback(JdkFutureAdapters.listenInPoolThread(trans.commit()), new FutureCallback<RpcResult<TransactionStatus>>() {
- @Override
- public void onSuccess(final RpcResult<TransactionStatus> result) {
- LOG.trace("Change committed successfully");
- }
-
- @Override
- public void onFailure(final Throwable t) {
- LOG.error("Failed to propagate change by listener {}", AbstractTopologyBuilder.this);
- }
- });
- }
-
- @Override
- public final void close() throws InterruptedException, ExecutionException {
- LOG.info("Shutting down builder for {}", getInstanceIdentifier());
- final DataModificationTransaction trans = this.dataProvider.beginTransaction();
- trans.removeOperationalData(getInstanceIdentifier());
- trans.commit().get();
- }
-
- @Override
- public final void onDataChanged(final DataChangeEvent<InstanceIdentifier<?>, DataObject> change) {
- final DataModificationTransaction trans = this.dataProvider.beginTransaction();
-
- try {
- onLocRIBChange(trans, change);
- } catch (final RuntimeException e) {
- LOG.warn("Data change {} was not completely propagated to listener {}", change, this, e);
- return;
- }
-
- switch (trans.getStatus()) {
- case COMMITED:
- case SUBMITED:
- break;
- case NEW:
- LOG.warn("Data change {} transaction {} was not committed by builder {}", change, trans, this);
- break;
- case CANCELED:
- case FAILED:
- LOG.error("Data change {} transaction {} failed to commit", change, trans);
- break;
- }
- }
+public abstract class AbstractTopologyBuilder<T extends Route>
+ implements ClusteredDataTreeChangeListener<T>, TopologyReference, FutureCallback<Empty> {
+ 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> 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<Tables> tablesId = locRibReference.getInstanceIdentifier()
+ .child(LocRib.class).child(Tables.class, new TablesKey(afi, safi));
+ final DataTreeIdentifier<T> id = DataTreeIdentifier.create(LogicalDatastoreType.OPERATIONAL,
+ getRouteWildcard(tablesId));
+
+ listenerRegistration = dataProvider.registerDataTreeChangeListener(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<T> getRouteWildcard(InstanceIdentifier<Tables> tablesId);
+
+ protected abstract void createObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
+
+ protected abstract void removeObject(ReadWriteTransaction trans, InstanceIdentifier<T> id, T value);
+
+ protected abstract void clearTopology();
+
+ @Override
+ public final InstanceIdentifier<Topology> getInstanceIdentifier() {
+ return topology;
+ }
+
+ public final synchronized FluentFuture<? extends CommitInfo> 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<? extends CommitInfo> future = destroyOperationalTopology();
+ destroyTransactionChain();
+ return future;
+ }
+
+ @Override
+ @SuppressWarnings("checkstyle:IllegalCatch")
+ public synchronized void onDataTreeChanged(final List<DataTreeModification<T>> 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<T> 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<CommitInfo>() {
+ @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<T> change : changes) {
+ routeChanged(change, null);
+ }
+ }
+ }
+
+ @VisibleForTesting
+ protected void routeChanged(final DataTreeModification<T> change, final ReadWriteTransaction trans) {
+ final DataObjectModification<T> root = change.getRootNode();
+ switch (root.getModificationType()) {
+ case DELETE:
+ removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
+ break;
+ case SUBTREE_MODIFIED:
+ case WRITE:
+ if (root.getDataBefore() != null) {
+ removeObject(trans, change.getRootPath().getRootIdentifier(), root.getDataBefore());
+ }
+ createObject(trans, change.getRootPath().getRootIdentifier(), root.getDataAfter());
+ break;
+ default:
+ throw new IllegalArgumentException("Unhandled modification type " + root.getModificationType());
+ }
+ }
+
+ 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<CommitInfo>() {
+ @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<? extends CommitInfo> destroyOperationalTopology() {
+ requireNonNull(chain, "A valid transaction chain must be provided.");
+ final WriteTransaction trans = chain.newWriteOnlyTransaction();
+ trans.delete(LogicalDatastoreType.OPERATIONAL, getInstanceIdentifier());
+ final FluentFuture<? extends CommitInfo> future = trans.commit();
+ future.addCallback(new FutureCallback<CommitInfo>() {
+ @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());
+ }
}
Code Review / bgpcep.git / blobdiff