pcep/topology/topology-provider/src/main/java/org/opendaylight/bgpcep/pcep/topology/provider/AbstractTopologySessionListener.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.bgpcep.pcep.topology.provider;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.collect.Iterables;
  13 import com.google.common.collect.Maps;
  14 import com.google.common.util.concurrent.FluentFuture;
  15 import com.google.common.util.concurrent.FutureCallback;
  16 import com.google.common.util.concurrent.Futures;
  17 import com.google.common.util.concurrent.ListenableFuture;
  18 import com.google.common.util.concurrent.MoreExecutors;
  19 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  20 import io.netty.util.concurrent.FutureListener;
  21 import java.net.InetAddress;
  22 import java.util.ArrayList;
  23 import java.util.Collection;
  24 import java.util.HashMap;
  25 import java.util.List;
  26 import java.util.Map;
  27 import java.util.Map.Entry;
  28 import java.util.Objects;
  29 import java.util.Optional;
  30 import java.util.Timer;
  31 import java.util.TimerTask;
  32 import java.util.concurrent.ConcurrentHashMap;
  33 import java.util.concurrent.TimeUnit;
  34 import java.util.concurrent.atomic.AtomicBoolean;
  35 import org.checkerframework.checker.lock.qual.GuardedBy;
  36 import org.checkerframework.checker.lock.qual.Holding;
  37 import org.opendaylight.bgpcep.pcep.topology.provider.session.stats.SessionStateImpl;
  38 import org.opendaylight.bgpcep.pcep.topology.provider.session.stats.TopologySessionStats;
  39 import org.opendaylight.mdsal.binding.api.WriteTransaction;
  40 import org.opendaylight.mdsal.common.api.CommitInfo;
  41 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  42 import org.opendaylight.protocol.pcep.PCEPCloseTermination;
  43 import org.opendaylight.protocol.pcep.PCEPSession;
  44 import org.opendaylight.protocol.pcep.PCEPTerminationReason;
  45 import org.opendaylight.protocol.pcep.TerminationReason;
  46 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IetfInetUtil;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.ietf.stateful.rev200720.LspObject;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.ietf.stateful.rev200720.Path1;
  49 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.ietf.stateful.rev200720.lsp.object.Lsp;
  50 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.Message;
  51 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.MessageHeader;
  52 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.Object;
  53 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.ProtocolVersion;
  54 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.LspId;
  55 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.Node1;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.Node1Builder;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.OperationResult;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.PccSyncState;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.TearDownSessionInput;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.lsp.metadata.Metadata;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.PathComputationClient;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.PathComputationClientBuilder;
  63 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.path.computation.client.ReportedLsp;
  64 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.path.computation.client.ReportedLspBuilder;
  65 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.path.computation.client.ReportedLspKey;
  66 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.path.computation.client.reported.lsp.Path;
  67 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.topology.pcep.rev200120.pcep.client.attributes.path.computation.client.reported.lsp.PathKey;
  68 import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.Node;
  69 import org.opendaylight.yangtools.yang.binding.DataObject;
  70 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  71 import org.opendaylight.yangtools.yang.common.RpcResult;
  72 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  73 import org.opendaylight.yangtools.yang.common.Uint8;
  74 import org.slf4j.Logger;
  75 import org.slf4j.LoggerFactory;
  76
  77 /**
  78  * Base class for PCEP topology providers. It handles the common tasks involved in managing a PCEP server (PCE)
  79  * endpoint, and exposing a network topology based on it. It needs to be subclassed to form a fully functional block,
  80  * where the subclass provides handling of incoming messages.
  81  *
  82  * @param <S> identifier type of requests
  83  * @param <L> identifier type for LSPs
  84  */
  85 public abstract class AbstractTopologySessionListener<S, L> implements TopologySessionListener, TopologySessionStats {
  86     private static final Logger LOG = LoggerFactory.getLogger(AbstractTopologySessionListener.class);
  87
  88     static final String MISSING_XML_TAG = "Mandatory XML tags are missing.";
  89     static final MessageHeader MESSAGE_HEADER = new MessageHeader() {
  90         private final ProtocolVersion version = new ProtocolVersion(Uint8.ONE);
  91
  92         @Override
  93         public Class<MessageHeader> implementedInterface() {
  94             return MessageHeader.class;
  95         }
  96
  97         @Override
  98         public ProtocolVersion getVersion() {
  99             return this.version;
 100         }
 101     };
 102
 103     @GuardedBy("this")
 104     final Map<L, String> lsps = new HashMap<>();
 105     @GuardedBy("this")
 106     SessionStateImpl listenerState;
 107
 108     @GuardedBy("this")
 109     private final Map<S, PCEPRequest> requests = new HashMap<>();
 110     @GuardedBy("this")
 111     private final Map<String, ReportedLsp> lspData = new ConcurrentHashMap<>();
 112     private final ServerSessionManager serverSessionManager;
 113     private InstanceIdentifier<PathComputationClient> pccIdentifier;
 114     @GuardedBy("this")
 115     private TopologyNodeState nodeState;
 116     private final AtomicBoolean synced = new AtomicBoolean(false);
 117     @GuardedBy("this")
 118     private PCEPSession session;
 119     @GuardedBy("this")
 120     private SyncOptimization syncOptimization;
 121     @GuardedBy("this")
 122     private boolean triggeredResyncInProcess;
 123
 124     AbstractTopologySessionListener(final ServerSessionManager serverSessionManager) {
 125         this.serverSessionManager = requireNonNull(serverSessionManager);
 126     }
 127
 128     @Override
 129     public final void onSessionUp(final PCEPSession psession) {
 130         synchronized (this.serverSessionManager) {
 131             synchronized (this) {
 132                 /*
 133                  * The session went up. Look up the router in Inventory model, create it if it
 134                  * is not there (marking that fact for later deletion), and mark it as
 135                  * synchronizing. Also create it in the topology model, with empty LSP list.
 136                  */
 137                 final InetAddress peerAddress = psession.getRemoteAddress();
 138
 139                 this.syncOptimization = new SyncOptimization(psession);
 140
 141                 final TopologyNodeState state =
 142                         this.serverSessionManager.takeNodeState(peerAddress, this, isLspDbRetreived());
 143
 144                 // takeNodeState(..) may fail when the server session manager is being restarted
 145                 // due to configuration change
 146                 if (state == null) {
 147                     LOG.error("Unable to fetch topology node state for PCEP session. Closing session {}", psession);
 148                     psession.close(TerminationReason.UNKNOWN);
 149                     this.onSessionTerminated(psession, new PCEPCloseTermination(TerminationReason.UNKNOWN));
 150                     return;
 151                 }
 152
 153                 if (this.session != null || this.nodeState != null) {
 154                     LOG.error("PCEP session is already up with {}. Closing session {}", psession.getRemoteAddress(),
 155                             psession);
 156                     psession.close(TerminationReason.UNKNOWN);
 157                     this.onSessionTerminated(psession, new PCEPCloseTermination(TerminationReason.UNKNOWN));
 158                     return;
 159                 }
 160                 this.session = psession;
 161                 this.nodeState = state;
 162
 163                 LOG.trace("Peer {} resolved to topology node {}", peerAddress, state.getNodeId());
 164
 165                 // Our augmentation in the topology node
 166                 final PathComputationClientBuilder pccBuilder = new PathComputationClientBuilder();
 167
 168                 onSessionUp(psession, pccBuilder);
 169                 this.synced.set(isSynchronized());
 170
 171                 pccBuilder.setIpAddress(IetfInetUtil.INSTANCE.ipAddressNoZoneFor(peerAddress));
 172                 final InstanceIdentifier<Node1> topologyAugment = state.getNodeId().augmentation(Node1.class);
 173                 this.pccIdentifier = topologyAugment.child(PathComputationClient.class);
 174                 final Node initialNodeState = state.getInitialNodeState();
 175                 final boolean isNodePresent = isLspDbRetreived() && initialNodeState != null;
 176                 if (isNodePresent) {
 177                     loadLspData(initialNodeState, this.lspData, this.lsps, isIncrementalSynchro());
 178                     pccBuilder.setReportedLsp(
 179                             initialNodeState.augmentation(Node1.class).getPathComputationClient().getReportedLsp());
 180                 }
 181                 state.storeNode(topologyAugment,
 182                         new Node1Builder().setPathComputationClient(pccBuilder.build()).build(), this.session);
 183
 184                 this.listenerState = new SessionStateImpl(this, psession);
 185                 this.serverSessionManager.bind(this.nodeState.getNodeId(), this.listenerState);
 186                 LOG.info("Session with {} attached to topology node {}", psession.getRemoteAddress(),
 187                         state.getNodeId());
 188             }
 189         }
 190     }
 191
 192     synchronized void updatePccState(final PccSyncState pccSyncState) {
 193         if (this.nodeState == null) {
 194             LOG.info("Server Session Manager is closed.");
 195             AbstractTopologySessionListener.this.session.close(TerminationReason.UNKNOWN);
 196             return;
 197         }
 198         final MessageContext ctx = new MessageContext(this.nodeState.getChain().newWriteOnlyTransaction());
 199         updatePccNode(ctx, new PathComputationClientBuilder().setStateSync(pccSyncState).build());
 200         if (pccSyncState != PccSyncState.Synchronized) {
 201             this.synced.set(false);
 202             this.triggeredResyncInProcess = true;
 203         }
 204         // All set, commit the modifications
 205         ctx.trans.commit().addCallback(new FutureCallback<CommitInfo>() {
 206             @Override
 207             public void onSuccess(final CommitInfo result) {
 208                 LOG.trace("Pcc Internal state for session {} updated successfully",
 209                         AbstractTopologySessionListener.this.session);
 210             }
 211
 212             @Override
 213             public void onFailure(final Throwable throwable) {
 214                 LOG.error("Failed to update Pcc internal state for session {}",
 215                         AbstractTopologySessionListener.this.session, throwable);
 216                 AbstractTopologySessionListener.this.session.close(TerminationReason.UNKNOWN);
 217             }
 218         }, MoreExecutors.directExecutor());
 219     }
 220
 221     synchronized boolean isTriggeredSyncInProcess() {
 222         return this.triggeredResyncInProcess;
 223     }
 224
 225     /**
 226      * Tear down the given PCEP session. It's OK to call this method even after the session
 227      * is already down. It always clear up the current session status.
 228      */
 229     @SuppressWarnings("checkstyle:IllegalCatch")
 230     private void tearDown(final PCEPSession psession) {
 231         requireNonNull(psession);
 232         synchronized (this.serverSessionManager) {
 233             synchronized (this) {
 234                 this.serverSessionManager.releaseNodeState(this.nodeState, psession, isLspDbPersisted());
 235                 clearNodeState();
 236
 237                 try {
 238                     if (this.session != null) {
 239                         this.session.close();
 240                     }
 241                     psession.close();
 242                 } catch (final Exception e) {
 243                     LOG.error("Session {} cannot be closed.", psession, e);
 244                 }
 245                 this.session = null;
 246                 this.listenerState = null;
 247                 this.syncOptimization = null;
 248
 249                 // Clear all requests we know about
 250                 for (final Entry<S, PCEPRequest> e : this.requests.entrySet()) {
 251                     final PCEPRequest r = e.getValue();
 252                     switch (r.getState()) {
 253                         case DONE:
 254                             // Done is done, nothing to do
 255                             LOG.trace("Request {} was done when session went down.", e.getKey());
 256                             break;
 257                         case UNACKED:
 258                             // Peer has not acked: results in failure
 259                             LOG.info("Request {} was incomplete when session went down, failing the instruction",
 260                                     e.getKey());
 261                             r.done(OperationResults.NOACK);
 262                             break;
 263                         case UNSENT:
 264                             // Peer has not been sent to the peer: results in cancellation
 265                             LOG.debug("Request {} was not sent when session went down, cancelling the instruction",
 266                                     e.getKey());
 267                             r.done(OperationResults.UNSENT);
 268                             break;
 269                         default:
 270                             break;
 271                     }
 272                 }
 273                 this.requests.clear();
 274             }
 275         }
 276     }
 277
 278     @Override
 279     public final void onSessionDown(final PCEPSession psession, final Exception exception) {
 280         LOG.warn("Session {} went down unexpectedly", psession, exception);
 281         tearDown(psession);
 282     }
 283
 284     @Override
 285     public final void onSessionTerminated(final PCEPSession psession, final PCEPTerminationReason reason) {
 286         LOG.info("Session {} terminated by peer with reason {}", psession, reason);
 287         tearDown(psession);
 288     }
 289
 290     @Override
 291     public final synchronized void onMessage(final PCEPSession psession, final Message message) {
 292         if (this.nodeState == null) {
 293             LOG.warn("Topology node state is null. Unhandled message {} on session {}", message, psession);
 294             psession.close(TerminationReason.UNKNOWN);
 295             return;
 296         }
 297         final MessageContext ctx = new MessageContext(this.nodeState.getChain().newWriteOnlyTransaction());
 298
 299         if (onMessage(ctx, message)) {
 300             LOG.warn("Unhandled message {} on session {}", message, psession);
 301             //cancel not supported, submit empty transaction
 302             ctx.trans.commit().addCallback(new FutureCallback<CommitInfo>() {
 303                 @Override
 304                 public void onSuccess(final CommitInfo result) {
 305                     LOG.trace("Successful commit");
 306                 }
 307
 308                 @Override
 309                 public void onFailure(final Throwable trw) {
 310                     LOG.error("Failed commit", trw);
 311                 }
 312             }, MoreExecutors.directExecutor());
 313             return;
 314         }
 315
 316         ctx.trans.commit().addCallback(new FutureCallback<CommitInfo>() {
 317             @Override
 318             public void onSuccess(final CommitInfo result) {
 319                 LOG.trace("Internal state for session {} updated successfully", psession);
 320                 ctx.notifyRequests();
 321
 322             }
 323
 324             @Override
 325             public void onFailure(final Throwable throwable) {
 326                 LOG.error("Failed to update internal state for session {}, closing it", psession, throwable);
 327                 ctx.notifyRequests();
 328                 psession.close(TerminationReason.UNKNOWN);
 329             }
 330         }, MoreExecutors.directExecutor());
 331     }
 332
 333     @Override
 334     public void close() {
 335         synchronized (this.serverSessionManager) {
 336             synchronized (this) {
 337                 clearNodeState();
 338                 if (this.session != null) {
 339                     LOG.info("Closing session {}", session);
 340                     this.session.close(TerminationReason.UNKNOWN);
 341                 }
 342             }
 343         }
 344     }
 345
 346     @Holding({"this.serverSessionManager", "this"})
 347     private void clearNodeState() {
 348         if (this.nodeState != null) {
 349             this.serverSessionManager.unbind(this.nodeState.getNodeId());
 350             LOG.debug("Clear Node state: {}", this.nodeState.getNodeId());
 351             this.nodeState = null;
 352         }
 353     }
 354
 355     final synchronized PCEPRequest removeRequest(final S id) {
 356         final PCEPRequest ret = this.requests.remove(id);
 357         if (ret != null && this.listenerState != null) {
 358             this.listenerState.processRequestStats(ret.getElapsedMillis());
 359         }
 360         LOG.trace("Removed request {} object {}", id, ret);
 361         return ret;
 362     }
 363
 364     final synchronized ListenableFuture<OperationResult> sendMessage(final Message message, final S requestId,
 365             final Metadata metadata) {
 366         final io.netty.util.concurrent.Future<Void> f = this.session.sendMessage(message);
 367         this.listenerState.updateStatefulSentMsg(message);
 368         final PCEPRequest req = new PCEPRequest(metadata);
 369         this.requests.put(requestId, req);
 370         final short rpcTimeout = this.serverSessionManager.getRpcTimeout();
 371         LOG.trace("RPC response timeout value is {} seconds", rpcTimeout);
 372         if (rpcTimeout > 0) {
 373             setupTimeoutHandler(requestId, req, rpcTimeout);
 374         }
 375
 376         f.addListener((FutureListener<Void>) future -> {
 377             if (!future.isSuccess()) {
 378                 synchronized (AbstractTopologySessionListener.this) {
 379                     AbstractTopologySessionListener.this.requests.remove(requestId);
 380                 }
 381                 req.done(OperationResults.UNSENT);
 382                 LOG.info("Failed to send request {}, instruction cancelled", requestId, future.cause());
 383             } else {
 384                 req.sent();
 385                 LOG.trace("Request {} sent to peer (object {})", requestId, req);
 386             }
 387         });
 388
 389         return req.getFuture();
 390     }
 391
 392     private void setupTimeoutHandler(final S requestId, final PCEPRequest req, final short timeout) {
 393         final Timer timer = req.getTimer();
 394         timer.schedule(new TimerTask() {
 395             @Override
 396             public void run() {
 397                 synchronized (AbstractTopologySessionListener.this) {
 398                     AbstractTopologySessionListener.this.requests.remove(requestId);
 399                 }
 400                 req.done();
 401                 LOG.info("Request {} timed-out waiting for response", requestId);
 402             }
 403         }, TimeUnit.SECONDS.toMillis(timeout));
 404         LOG.trace("Set up response timeout handler for request {}", requestId);
 405     }
 406
 407     /**
 408      * Update an LSP in the data store.
 409      *
 410      * @param ctx       Message context
 411      * @param id        Revision-specific LSP identifier
 412      * @param lspName   LSP name
 413      * @param rlb       Reported LSP builder
 414      * @param solicited True if the update was solicited
 415      * @param remove    True if this is an LSP path removal
 416      */
 417     protected final synchronized void updateLsp(final MessageContext ctx, final L id, final String lspName,
 418             final ReportedLspBuilder rlb, final boolean solicited, final boolean remove) {
 419
 420         final String name;
 421         if (lspName == null) {
 422             name = this.lsps.get(id);
 423             if (name == null) {
 424                 LOG.error("PLSPID {} seen for the first time, not reporting the LSP", id);
 425                 return;
 426             }
 427         } else {
 428             name = lspName;
 429         }
 430
 431         LOG.debug("Saved LSP {} with name {}", id, name);
 432         this.lsps.put(id, name);
 433
 434
 435         final ReportedLsp previous = this.lspData.get(name);
 436         // if no previous report about the lsp exist, just proceed
 437         if (previous != null) {
 438             final Map<PathKey, Path> updatedPaths = makeBeforeBreak(rlb, previous, name, remove);
 439             // if all paths or the last path were deleted, delete whole tunnel
 440             if (updatedPaths.isEmpty()) {
 441                 LOG.debug("All paths were removed, removing LSP with {}.", id);
 442                 removeLsp(ctx, id);
 443                 return;
 444             }
 445             rlb.setPath(updatedPaths);
 446         }
 447         rlb.withKey(new ReportedLspKey(name));
 448         rlb.setName(name);
 449
 450         // If this is an unsolicited update. We need to make sure we retain the metadata already present
 451         if (solicited) {
 452             this.nodeState.setLspMetadata(name, rlb.getMetadata());
 453         } else {
 454             rlb.setMetadata(this.nodeState.getLspMetadata(name));
 455         }
 456
 457         final ReportedLsp rl = rlb.build();
 458         ctx.trans.put(LogicalDatastoreType.OPERATIONAL, this.pccIdentifier.child(ReportedLsp.class, rlb.key()), rl);
 459         LOG.debug("LSP {} updated to MD-SAL", name);
 460
 461         this.lspData.put(name, rl);
 462     }
 463
 464     private static Map<PathKey, Path> makeBeforeBreak(final ReportedLspBuilder rlb, final ReportedLsp previous,
 465             final String name, final boolean remove) {
 466         // just one path should be reported
 467         final Path path = Iterables.getOnlyElement(rlb.getPath().values());
 468         final org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820.LspId reportedLspId =
 469                 path.getLspId();
 470         final List<Path> updatedPaths;
 471         //lspId = 0 and remove = false -> tunnel is down, still exists but no path is signaled
 472         //remove existing tunnel's paths now, as explicit path remove will not come
 473         if (!remove && reportedLspId.getValue().toJava() == 0) {
 474             updatedPaths = new ArrayList<>();
 475             LOG.debug("Remove previous paths {} to this lsp name {}", previous.getPath(), name);
 476         } else {
 477             // check previous report for existing paths
 478             final Collection<Path> prev = previous.nonnullPath().values();
 479             updatedPaths = new ArrayList<>(prev);
 480             LOG.debug("Found previous paths {} to this lsp name {}", updatedPaths, name);
 481             for (final Path prevPath : prev) {
 482                 //we found reported path in previous reports
 483                 if (prevPath.getLspId().getValue().toJava() == 0 || prevPath.getLspId().equals(reportedLspId)) {
 484                     LOG.debug("Match on lsp-id {}", prevPath.getLspId().getValue());
 485                     // path that was reported previously and does have the same lsp-id, path will be updated
 486                     final boolean r = updatedPaths.remove(prevPath);
 487                     LOG.trace("Request removed? {}", r);
 488                 }
 489             }
 490         }
 491         // if the path does not exist in previous report, add it to path list, it's a new ERO
 492         // only one path will be added
 493         //lspId is 0 means confirmation message that shouldn't be added (because we have no means of deleting it later)
 494         LOG.trace("Adding new path {} to {}", path, updatedPaths);
 495         updatedPaths.add(path);
 496         if (remove) {
 497             if (reportedLspId.getValue().toJava() == 0) {
 498                 // if lsp-id also 0, remove all paths
 499                 LOG.debug("Removing all paths.");
 500                 updatedPaths.clear();
 501             } else {
 502                 // path is marked to be removed
 503                 LOG.debug("Removing path {} from {}", path, updatedPaths);
 504                 final boolean r = updatedPaths.remove(path);
 505                 LOG.trace("Request removed? {}", r);
 506             }
 507         }
 508         LOG.debug("Setting new paths {} to lsp {}", updatedPaths, name);
 509         return Maps.uniqueIndex(updatedPaths, Path::key);
 510     }
 511
 512     /**
 513      * Indicate that the peer has completed state synchronization.
 514      *
 515      * @param ctx Message context
 516      */
 517     protected final synchronized void stateSynchronizationAchieved(final MessageContext ctx) {
 518         if (this.synced.getAndSet(true)) {
 519             LOG.debug("State synchronization achieved while synchronizing, not updating state");
 520             return;
 521         }
 522         if (this.triggeredResyncInProcess) {
 523             this.triggeredResyncInProcess = false;
 524         }
 525         updatePccNode(ctx, new PathComputationClientBuilder().setStateSync(PccSyncState.Synchronized).build());
 526
 527         // The node has completed synchronization, cleanup metadata no longer reported back
 528         this.nodeState.cleanupExcept(this.lsps.values());
 529         LOG.debug("Session {} achieved synchronized state", this.session);
 530     }
 531
 532     protected final synchronized void updatePccNode(final MessageContext ctx, final PathComputationClient pcc) {
 533         ctx.trans.merge(LogicalDatastoreType.OPERATIONAL, this.pccIdentifier, pcc);
 534     }
 535
 536     protected final InstanceIdentifier<ReportedLsp> lspIdentifier(final String name) {
 537         return this.pccIdentifier.child(ReportedLsp.class, new ReportedLspKey(name));
 538     }
 539
 540     /**
 541      * Remove LSP from the database.
 542      *
 543      * @param ctx Message Context
 544      * @param id  Revision-specific LSP identifier
 545      */
 546     protected final synchronized void removeLsp(final MessageContext ctx, final L id) {
 547         final String name = this.lsps.remove(id);
 548         LOG.debug("LSP {} removed", name);
 549         ctx.trans.delete(LogicalDatastoreType.OPERATIONAL, lspIdentifier(name));
 550         this.lspData.remove(name);
 551     }
 552
 553     @SuppressWarnings("checkstyle:OverloadMethodsDeclarationOrder")
 554     protected abstract void onSessionUp(PCEPSession session, PathComputationClientBuilder pccBuilder);
 555
 556     /**
 557      * Perform revision-specific message processing when a message arrives.
 558      *
 559      * @param ctx     Message processing context
 560      * @param message Protocol message
 561      * @return True if the message type is not handle.
 562      */
 563     @SuppressWarnings("checkstyle:OverloadMethodsDeclarationOrder")
 564     protected abstract boolean onMessage(MessageContext ctx, Message message);
 565
 566     @Holding("this")
 567     final String lookupLspName(final L id) {
 568         return this.lsps.get(requireNonNull(id, "ID parameter null."));
 569     }
 570
 571     /**
 572      * Reads operational data on this node. Doesn't attempt to read the data,
 573      * if the node does not exist. In this case returns null.
 574      *
 575      * @param id InstanceIdentifier of the node
 576      * @return null if the node does not exists, or operational data
 577      */
 578     final synchronized <T extends DataObject> FluentFuture<Optional<T>>
 579         readOperationalData(final InstanceIdentifier<T> id) {
 580         if (this.nodeState == null) {
 581             return null;
 582         }
 583         return this.nodeState.readOperationalData(id);
 584     }
 585
 586     protected abstract Object validateReportedLsp(Optional<ReportedLsp> rep, LspId input);
 587
 588     protected abstract void loadLspData(Node node, Map<String, ReportedLsp> lspData, Map<L, String> lsps,
 589             boolean incrementalSynchro);
 590
 591     final boolean isLspDbPersisted() {
 592         return this.syncOptimization != null && this.syncOptimization.isSyncAvoidanceEnabled();
 593     }
 594
 595     final boolean isLspDbRetreived() {
 596         return this.syncOptimization != null && this.syncOptimization.isDbVersionPresent();
 597     }
 598
 599     /**
 600      * Is Incremental synchronization if LSP-DB-VERSION are included,
 601      * LSP-DB-VERSION TLV values doesnt match, and  LSP-SYNC-CAPABILITY is enabled.
 602      */
 603     final synchronized boolean isIncrementalSynchro() {
 604         return this.syncOptimization != null && this.syncOptimization.isSyncAvoidanceEnabled()
 605                 && this.syncOptimization.isDeltaSyncEnabled();
 606     }
 607
 608     final synchronized boolean isTriggeredInitialSynchro() {
 609         return this.syncOptimization != null && this.syncOptimization.isTriggeredInitSyncEnabled();
 610     }
 611
 612     final synchronized boolean isTriggeredReSyncEnabled() {
 613         return this.syncOptimization != null && this.syncOptimization.isTriggeredReSyncEnabled();
 614     }
 615
 616     protected final synchronized boolean isSynchronized() {
 617         return this.syncOptimization != null && this.syncOptimization.doesLspDbMatch();
 618     }
 619
 620     @Override
 621     public int getDelegatedLspsCount() {
 622         return Math.toIntExact(this.lspData.values().stream()
 623             .map(ReportedLsp::getPath).filter(pathList -> pathList != null && !pathList.isEmpty())
 624             // pick the first path, as delegate status should be same in each path
 625             .map(pathList -> pathList.values().iterator().next())
 626             .map(path -> path.augmentation(Path1.class)).filter(Objects::nonNull)
 627             .map(LspObject::getLsp).filter(Objects::nonNull)
 628             .filter(Lsp::getDelegate)
 629             .count());
 630     }
 631
 632     @Override
 633     public boolean isSessionSynchronized() {
 634         return this.synced.get();
 635     }
 636
 637     @Override
 638     public synchronized ListenableFuture<RpcResult<Void>> tearDownSession(final TearDownSessionInput input) {
 639         close();
 640         return Futures.immediateFuture(RpcResultBuilder.<Void>success().build());
 641     }
 642
 643     static final class MessageContext {
 644         private final Collection<PCEPRequest> requests = new ArrayList<>();
 645         private final WriteTransaction trans;
 646
 647         private MessageContext(final WriteTransaction trans) {
 648             this.trans = requireNonNull(trans);
 649         }
 650
 651         void resolveRequest(final PCEPRequest req) {
 652             this.requests.add(req);
 653         }
 654
 655         @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
 656                 justification = "https://github.com/spotbugs/spotbugs/issues/811")
 657         private void notifyRequests() {
 658             for (final PCEPRequest r : this.requests) {
 659                 r.done(OperationResults.SUCCESS);
 660             }
 661         }
 662     }
 663 }