trace/mdsal-trace-impl/src/main/java/org/opendaylight/mdsal/trace/impl/TracingBroker.java

   1 /*
   2  * Copyright (c) 2016 Red Hat, 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.mdsal.trace.impl;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  13 import java.io.PrintStream;
  14 import java.util.ArrayList;
  15 import java.util.List;
  16 import java.util.Set;
  17 import org.opendaylight.mdsal.binding.dom.codec.api.BindingCodecTree;
  18 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  19 import org.opendaylight.mdsal.dom.api.ClusteredDOMDataTreeChangeListener;
  20 import org.opendaylight.mdsal.dom.api.DOMDataBroker;
  21 import org.opendaylight.mdsal.dom.api.DOMDataTreeReadTransaction;
  22 import org.opendaylight.mdsal.dom.api.DOMDataTreeReadWriteTransaction;
  23 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteTransaction;
  24 import org.opendaylight.mdsal.dom.api.DOMTransactionChain;
  25 import org.opendaylight.mdsal.trace.api.TracingDOMDataBroker;
  26 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.mdsaltrace.rev160908.Config;
  27 import org.opendaylight.yangtools.yang.binding.DataObject;
  28 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  30 import org.slf4j.Logger;
  31 import org.slf4j.LoggerFactory;
  32
  33 @SuppressWarnings("checkstyle:JavadocStyle")
  34 //...because otherwise it whines about the elements in the @code block even though it's completely valid Javadoc
  35 /**
  36  * TracingBroker logs "write" operations and listener registrations to the md-sal. It logs the instance identifier path,
  37  * the objects themselves, as well as the stack trace of the call invoking the registration or write operation.
  38  * It works by operating as a "bump on the stack" between the application and actual DataBroker, intercepting write
  39  * and registration calls and writing to the log.
  40  *
  41  * <p>In addition, it (optionally) can also keep track of the stack trace of all new transaction allocations
  42  * (including TransactionChains, and transactions created in turn from them), in order to detect and report leaks
  43  * from transactions which were not closed.
  44  *
  45  * <h1>Wiring:</h1>
  46  * TracingBroker is designed to be easy to use. In fact, for bundles using Blueprint to inject their DataBroker
  47  * TracingBroker can be used without modifying your code at all in two simple steps:
  48  * <ol>
  49  * <li>
  50  * Simply add the dependency "mdsaltrace-features" to
  51  * your Karaf pom:
  52  * <pre>
  53  * {@code
  54  *  <dependency>
  55  *    <groupId>org.opendaylight.controller</groupId>
  56  *    <artifactId>features-mdsal-trace</artifactId>
  57  *    <version>1.7.0-SNAPSHOT</version>
  58  *    <classifier>features</classifier>
  59  *    <type>xml</type>
  60  *    <scope>runtime</scope>
  61  *  </dependency>
  62  * }
  63  * </pre>
  64  * </li>
  65  * <li>
  66  * Then just "feature:install odl-mdsal-trace" before you install your "real" feature(s) and you're done.
  67  * Beware that with Karaf 4 due to <a href="https://bugs.opendaylight.org/show_bug.cgi?id=9068">Bug 9068</a>
  68  * you'll probably have to use feature:install's --no-auto-refresh flag when installing your "real" feature.
  69  * </li>
  70  * </ol>
  71  * This works because the mdsaltrace-impl bundle registers its service implementing DOMDataBroker with a higher
  72  * rank than sal-binding-broker. As such, any OSGi service lookup for DataBroker will receive the TracingBroker.
  73  * <p> </p>
  74  * <h1>Avoiding log bloat:</h1>
  75  * TracingBroker can be configured to only print registrations or write ops pertaining to certain subtrees of the
  76  * md-sal. This can be done in the code via the methods of this class or via a config file. TracingBroker uses a more
  77  * convenient but non-standard representation of the instance identifiers. Each instance identifier segment's
  78  * class.getSimpleName() is used separated by a '/'.
  79  * <p> </p>
  80  * <h1>Known issues</h1>
  81  * <ul>
  82  *     <li>
  83  *        Filtering by paths. For some registrations the codec that converts back from the DOM to binding paths is
  84  *        busted. As such, an aproximated path is used in the output. For now it is recommended not to use
  85  *        watchRegistrations and allow all registrations to be logged.
  86  *     </li>
  87  * </ul>
  88  */
  89 public class TracingBroker implements TracingDOMDataBroker {
  90     private static final Logger LOG = LoggerFactory.getLogger(TracingBroker.class);
  91
  92     private static final int STACK_TRACE_FIRST_RELEVANT_FRAME = 2;
  93
  94     private final BindingCodecTree codec;
  95     private final DOMDataBroker delegate;
  96     private final List<Watch> registrationWatches = new ArrayList<>();
  97     private final List<Watch> writeWatches = new ArrayList<>();
  98
  99     private final boolean isDebugging;
 100     private final CloseTrackedRegistry<TracingTransactionChain> transactionChainsRegistry;
 101     private final CloseTrackedRegistry<TracingReadOnlyTransaction> readOnlyTransactionsRegistry;
 102     private final CloseTrackedRegistry<TracingWriteTransaction> writeTransactionsRegistry;
 103     private final CloseTrackedRegistry<TracingReadWriteTransaction> readWriteTransactionsRegistry;
 104
 105     private class Watch {
 106         final String iidString;
 107         final LogicalDatastoreType store;
 108
 109         Watch(final String iidString, final LogicalDatastoreType storeOrNull) {
 110             store = storeOrNull;
 111             this.iidString = iidString;
 112         }
 113
 114         private String toIidCompString(final YangInstanceIdentifier iid) {
 115             StringBuilder builder = new StringBuilder();
 116             toPathString(iid, builder);
 117             return builder.append('/').toString();
 118         }
 119
 120         private boolean isParent(final String parent, final String child) {
 121             int parentOffset = 0;
 122             if (parent.length() > 0 && parent.charAt(0) == '<') {
 123                 parentOffset = parent.indexOf('>') + 1;
 124             }
 125
 126             int childOffset = 0;
 127             if (child.length() > 0 && child.charAt(0) == '<') {
 128                 childOffset = child.indexOf('>') + 1;
 129             }
 130
 131             return child.startsWith(parent.substring(parentOffset), childOffset);
 132         }
 133
 134         @SuppressWarnings({ "checkstyle:hiddenField", "hiding" })
 135         public boolean subtreesOverlap(final YangInstanceIdentifier iid, final LogicalDatastoreType store) {
 136             if (this.store != null && !this.store.equals(store)) {
 137                 return false;
 138             }
 139
 140             String otherIidString = toIidCompString(iid);
 141             return isParent(iidString, otherIidString) || isParent(otherIidString, iidString);
 142         }
 143
 144         @SuppressWarnings({ "checkstyle:hiddenField", "hiding" })
 145         public boolean eventIsOfInterest(final YangInstanceIdentifier iid, final LogicalDatastoreType store) {
 146             if (this.store != null && !this.store.equals(store)) {
 147                 return false;
 148             }
 149
 150             return isParent(iidString, toPathString(iid));
 151         }
 152     }
 153
 154     public TracingBroker(final DOMDataBroker delegate, final Config config, final BindingCodecTree codec) {
 155         this.delegate = requireNonNull(delegate, "delegate");
 156         this.codec = requireNonNull(codec, "codec");
 157         configure(config);
 158
 159         isDebugging = Boolean.TRUE.equals(config.getTransactionDebugContextEnabled());
 160         final String db = "DataBroker";
 161         transactionChainsRegistry     = new CloseTrackedRegistry<>(db, "createTransactionChain()", isDebugging);
 162         readOnlyTransactionsRegistry  = new CloseTrackedRegistry<>(db, "newReadOnlyTransaction()", isDebugging);
 163         writeTransactionsRegistry     = new CloseTrackedRegistry<>(db, "newWriteOnlyTransaction()", isDebugging);
 164         readWriteTransactionsRegistry = new CloseTrackedRegistry<>(db, "newReadWriteTransaction()", isDebugging);
 165     }
 166
 167     private void configure(final Config config) {
 168         registrationWatches.clear();
 169         Set<String> paths = config.getRegistrationWatches();
 170         if (paths != null) {
 171             for (String path : paths) {
 172                 watchRegistrations(path, null);
 173             }
 174         }
 175
 176         writeWatches.clear();
 177         paths = config.getWriteWatches();
 178         if (paths != null) {
 179             for (String path : paths) {
 180                 watchWrites(path, null);
 181             }
 182         }
 183     }
 184
 185     /**
 186      * Log registrations to this subtree of the md-sal.
 187      * @param iidString the iid path of the root of the subtree
 188      * @param store Which LogicalDataStore? or null for both
 189      */
 190     public void watchRegistrations(final String iidString, final LogicalDatastoreType store) {
 191         LOG.info("Watching registrations to {} in {}", iidString, store);
 192         registrationWatches.add(new Watch(iidString, store));
 193     }
 194
 195     /**
 196      * Log writes to this subtree of the md-sal.
 197      * @param iidString the iid path of the root of the subtree
 198      * @param store Which LogicalDataStore? or null for both
 199      */
 200     public void watchWrites(final String iidString, final LogicalDatastoreType store) {
 201         LOG.info("Watching writes to {} in {}", iidString, store);
 202         Watch watch = new Watch(iidString, store);
 203         writeWatches.add(watch);
 204     }
 205
 206     private boolean isRegistrationWatched(final YangInstanceIdentifier iid, final LogicalDatastoreType store) {
 207         if (registrationWatches.isEmpty()) {
 208             return true;
 209         }
 210
 211         for (Watch regInterest : registrationWatches) {
 212             if (regInterest.subtreesOverlap(iid, store)) {
 213                 return true;
 214             }
 215         }
 216
 217         return false;
 218     }
 219
 220     boolean isWriteWatched(final YangInstanceIdentifier iid, final LogicalDatastoreType store) {
 221         if (writeWatches.isEmpty()) {
 222             return true;
 223         }
 224
 225         for (Watch watch : writeWatches) {
 226             if (watch.eventIsOfInterest(iid, store)) {
 227                 return true;
 228             }
 229         }
 230
 231         return false;
 232     }
 233
 234     static void toPathString(final InstanceIdentifier<? extends DataObject> iid, final StringBuilder builder) {
 235         for (var pathArg : iid.getPathArguments()) {
 236             builder.append('/').append(pathArg.type().getSimpleName());
 237         }
 238     }
 239
 240     String toPathString(final YangInstanceIdentifier  yiid) {
 241         StringBuilder sb = new StringBuilder();
 242         toPathString(yiid, sb);
 243         return sb.toString();
 244     }
 245
 246
 247     private void toPathString(final YangInstanceIdentifier yiid, final StringBuilder sb) {
 248         InstanceIdentifier<?> iid = codec.getInstanceIdentifierCodec().toBinding(yiid);
 249         if (null == iid) {
 250             reconstructIidPathString(yiid, sb);
 251         } else {
 252             toPathString(iid, sb);
 253         }
 254     }
 255
 256     private static void reconstructIidPathString(final YangInstanceIdentifier yiid, final StringBuilder sb) {
 257         sb.append("<RECONSTRUCTED FROM: \"").append(yiid.toString()).append("\">");
 258         for (YangInstanceIdentifier.PathArgument pathArg : yiid.getPathArguments()) {
 259             sb.append('/').append(pathArg.getNodeType().getLocalName());
 260         }
 261     }
 262
 263     String getStackSummary() {
 264         StackTraceElement[] stack = Thread.currentThread().getStackTrace();
 265
 266         StringBuilder sb = new StringBuilder();
 267         for (int i = STACK_TRACE_FIRST_RELEVANT_FRAME; i < stack.length; i++) {
 268             StackTraceElement frame = stack[i];
 269             sb.append("\n\t(TracingBroker)\t").append(frame.getClassName()).append('.').append(frame.getMethodName());
 270         }
 271
 272         return sb.toString();
 273     }
 274
 275     @Override
 276     public DOMDataTreeReadWriteTransaction newReadWriteTransaction() {
 277         return new TracingReadWriteTransaction(delegate.newReadWriteTransaction(), this, readWriteTransactionsRegistry);
 278     }
 279
 280     @Override
 281     public DOMDataTreeWriteTransaction newWriteOnlyTransaction() {
 282         return new TracingWriteTransaction(delegate.newWriteOnlyTransaction(), this, writeTransactionsRegistry);
 283     }
 284
 285     @Override
 286     public DOMTransactionChain createTransactionChain() {
 287         return new TracingTransactionChain(delegate.createTransactionChain(), this, transactionChainsRegistry);
 288     }
 289
 290     @Override
 291     public DOMTransactionChain createMergingTransactionChain() {
 292         return new TracingTransactionChain(delegate.createMergingTransactionChain(), this, transactionChainsRegistry);
 293     }
 294
 295     @Override
 296     public DOMDataTreeReadTransaction newReadOnlyTransaction() {
 297         return new TracingReadOnlyTransaction(delegate.newReadOnlyTransaction(), readOnlyTransactionsRegistry);
 298     }
 299
 300     @Override
 301     public <T extends Extension> T extension(final Class<T> type) {
 302         final var ext = delegate.extension(type);
 303         if (DataTreeChangeExtension.class.equals(type) && ext instanceof DataTreeChangeExtension treeChange) {
 304             return type.cast((DataTreeChangeExtension) (domDataTreeIdentifier, listener) -> {
 305                 final var rootId = domDataTreeIdentifier.path();
 306                 if (isRegistrationWatched(rootId, domDataTreeIdentifier.datastore())) {
 307                     LOG.warn("{} registration (registerDataTreeChangeListener) for {} from {}.",
 308                         listener instanceof ClusteredDOMDataTreeChangeListener ? "Clustered" : "Non-clustered",
 309                             toPathString(rootId), getStackSummary());
 310                 }
 311                 return treeChange.registerDataTreeChangeListener(domDataTreeIdentifier, listener);
 312             });
 313         }
 314         return ext;
 315     }
 316
 317     @Override
 318     public boolean printOpenTransactions(final PrintStream ps, final int minOpenTXs) {
 319         if (transactionChainsRegistry.getAllUnique().isEmpty()
 320             && readOnlyTransactionsRegistry.getAllUnique().isEmpty()
 321             && writeTransactionsRegistry.getAllUnique().isEmpty()
 322             && readWriteTransactionsRegistry.getAllUnique().isEmpty()) {
 323
 324             ps.println("No open transactions, great!");
 325             return false;
 326         }
 327
 328         ps.println(getClass().getSimpleName() + " found some not yet (or never..) closed transaction[chain]s!");
 329         ps.println("[NB: If no stack traces are shown below, then "
 330                  + "enable transaction-debug-context-enabled in mdsaltrace_config.xml]");
 331         ps.println();
 332         // Flag to track if we really found any real leaks with more (or equal) to minOpenTXs
 333         boolean hasFound = print(readOnlyTransactionsRegistry, ps, "  ", minOpenTXs);
 334         hasFound |= print(writeTransactionsRegistry, ps, "  ", minOpenTXs);
 335         hasFound |= print(readWriteTransactionsRegistry, ps, "  ", minOpenTXs);
 336
 337         // Now print details for each non-closed TransactionChain
 338         // incl. in turn each ones own read/Write[Only]TransactionsRegistry
 339         Set<CloseTrackedRegistryReportEntry<TracingTransactionChain>>
 340             entries = transactionChainsRegistry.getAllUnique();
 341         if (!entries.isEmpty()) {
 342             ps.println("  " + transactionChainsRegistry.getAnchor() + " : "
 343                     + transactionChainsRegistry.getCreateDescription());
 344         }
 345         for (CloseTrackedRegistryReportEntry<TracingTransactionChain> entry : entries) {
 346             ps.println("    " + entry.getNumberAddedNotRemoved() + "x TransactionChains opened but not closed here:");
 347             printStackTraceElements(ps, "      ", entry.getStackTraceElements());
 348             @SuppressWarnings("resource")
 349             TracingTransactionChain txChain = (TracingTransactionChain) entry
 350                 .getExampleCloseTracked().getRealCloseTracked();
 351             hasFound |= print(txChain.getReadOnlyTransactionsRegistry(), ps, "        ", minOpenTXs);
 352             hasFound |= print(txChain.getWriteTransactionsRegistry(), ps, "        ", minOpenTXs);
 353             hasFound |= print(txChain.getReadWriteTransactionsRegistry(), ps, "        ", minOpenTXs);
 354         }
 355         ps.println();
 356
 357         return hasFound;
 358     }
 359
 360     final void logEmptySet(final YangInstanceIdentifier yiid) {
 361         if (LOG.isDebugEnabled()) {
 362             LOG.debug("Empty data set write to {}", toPathString(yiid));
 363         }
 364     }
 365
 366     @SuppressFBWarnings(value = "SLF4J_SIGN_ONLY_FORMAT", justification = "pre-formatted logs")
 367     static final void logOperations(final Object identifier, final List<?> operations) {
 368         if (LOG.isWarnEnabled()) {
 369             LOG.warn("Transaction {} contains the following operations:", identifier);
 370             for (var operation : operations) {
 371                 LOG.warn("{}", operation);
 372             }
 373         }
 374     }
 375
 376     private <T extends CloseTracked<T>> boolean print(final CloseTrackedRegistry<T> registry, final PrintStream ps,
 377             final String indent, final int minOpenTransactions) {
 378         Set<CloseTrackedRegistryReportEntry<T>> unsorted = registry.getAllUnique();
 379         if (unsorted.size() < minOpenTransactions) {
 380             return false;
 381         }
 382
 383         List<CloseTrackedRegistryReportEntry<T>> entries = new ArrayList<>(unsorted);
 384         entries.sort((o1, o2) -> Long.compare(o2.getNumberAddedNotRemoved(), o1.getNumberAddedNotRemoved()));
 385
 386         if (!entries.isEmpty()) {
 387             ps.println(indent + registry.getAnchor() + " : " + registry.getCreateDescription());
 388         }
 389         entries.forEach(entry -> {
 390             ps.println(indent + "  " + entry.getNumberAddedNotRemoved()
 391                 + "x transactions opened here, which are not closed:");
 392             printStackTraceElements(ps, indent + "    ", entry.getStackTraceElements());
 393         });
 394         if (!entries.isEmpty()) {
 395             ps.println();
 396         }
 397         return true;
 398     }
 399
 400     private void printStackTraceElements(final PrintStream ps, final String indent,
 401             final List<StackTraceElement> stackTraceElements) {
 402         boolean ellipsis = false;
 403         for (final StackTraceElement stackTraceElement : stackTraceElements) {
 404             if (isStackTraceElementInteresting(stackTraceElement)) {
 405                 ps.println(indent + stackTraceElement);
 406                 ellipsis = false;
 407             } else if (!ellipsis) {
 408                 ps.println(indent + "(...)");
 409                 ellipsis = true;
 410             }
 411         }
 412     }
 413
 414     private boolean isStackTraceElementInteresting(final StackTraceElement element) {
 415         final String className = element.getClassName();
 416         return !className.startsWith(getClass().getPackage().getName())
 417             && !className.startsWith(CloseTracked.class.getPackage().getName())
 418             && !className.startsWith("Proxy")
 419             && !className.startsWith("akka")
 420             && !className.startsWith("scala")
 421             && !className.startsWith("sun.reflect")
 422             && !className.startsWith("java.lang.reflect")
 423             && !className.startsWith("org.apache.aries.blueprint")
 424             && !className.startsWith("org.osgi.util.tracker");
 425     }
 426 }