opendaylight/config/config-manager/src/main/java/org/opendaylight/controller/config/manager/impl/osgi/BlankTransactionServiceTracker.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.controller.config.manager.impl.osgi;
   9
  10 import com.google.common.annotations.VisibleForTesting;
  11 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  12 import java.util.concurrent.ExecutorService;
  13 import java.util.concurrent.Executors;
  14 import javax.management.ObjectName;
  15 import org.opendaylight.controller.config.api.ConflictingVersionException;
  16 import org.opendaylight.controller.config.api.ValidationException;
  17 import org.opendaylight.controller.config.api.jmx.CommitStatus;
  18 import org.opendaylight.controller.config.manager.impl.ConfigRegistryImpl;
  19 import org.opendaylight.controller.config.spi.ModuleFactory;
  20 import org.osgi.framework.ServiceReference;
  21 import org.osgi.util.tracker.ServiceTrackerCustomizer;
  22 import org.slf4j.Logger;
  23 import org.slf4j.LoggerFactory;
  24
  25 /**
  26  * Every time factory is added or removed, blank transaction is triggered to handle
  27  * {@link org.opendaylight.controller.config.spi.ModuleFactory#getDefaultModules(org.opendaylight.controller.config.api.DependencyResolverFactory, org.osgi.framework.BundleContext)}
  28  * functionality.
  29  */
  30 public class BlankTransactionServiceTracker implements ServiceTrackerCustomizer<ModuleFactory, Object> {
  31     private static final Logger LOG = LoggerFactory.getLogger(BlankTransactionServiceTracker.class);
  32
  33     public static final int DEFAULT_MAX_ATTEMPTS = 10;
  34
  35     private final BlankTransaction blankTransaction;
  36     private final ExecutorService txExecutor;
  37     private final int maxAttempts;
  38
  39     public BlankTransactionServiceTracker(final ConfigRegistryImpl configRegistry) {
  40         this(() -> {
  41             ObjectName tx = configRegistry.beginConfig(true);
  42             return configRegistry.commitConfig(tx);
  43          });
  44     }
  45
  46     public BlankTransactionServiceTracker(final BlankTransaction blankTransaction) {
  47         this(blankTransaction, DEFAULT_MAX_ATTEMPTS, Executors.newSingleThreadExecutor(new ThreadFactoryBuilder()
  48                 .setNameFormat("config-blank-txn-%d").build()));
  49     }
  50
  51     @VisibleForTesting
  52     BlankTransactionServiceTracker(final BlankTransaction blankTx, final int maxAttempts,
  53             final ExecutorService txExecutor) {
  54         this.blankTransaction = blankTx;
  55         this.maxAttempts = maxAttempts;
  56         this.txExecutor = txExecutor;
  57     }
  58
  59     @Override
  60     public Object addingService(ServiceReference<ModuleFactory> moduleFactoryServiceReference) {
  61         blankTransactionAsync();
  62         return null;
  63     }
  64
  65     private void blankTransactionAsync() {
  66         txExecutor.execute(this::blankTransactionSync);
  67     }
  68
  69     void blankTransactionSync() {
  70         // race condition check: config-persister might push new configuration while server is starting up.
  71         ConflictingVersionException lastException = null;
  72         for (int i = 0; i < maxAttempts; i++) {
  73             try {
  74                 // create transaction
  75                 CommitStatus commitStatus = blankTransaction.hit();
  76                 LOG.debug("Committed blank transaction with status {}", commitStatus);
  77                 return;
  78             } catch (ConflictingVersionException e) {
  79                 lastException = e;
  80                 try {
  81                     Thread.sleep(1000);
  82                 } catch (InterruptedException interruptedException) {
  83                     Thread.currentThread().interrupt();
  84                     LOG.debug("blankTransactionSync was interrupted");
  85                     return;
  86                 }
  87             } catch (ValidationException e) {
  88                 LOG.error("Validation exception while running blank transaction indicates programming error", e);
  89             }
  90         }
  91
  92         LOG.error("Maximal number of attempts reached and still cannot get optimistic lock from config manager",
  93                 lastException);
  94     }
  95
  96     @Override
  97     public void modifiedService(ServiceReference <ModuleFactory> moduleFactoryServiceReference, Object o) {
  98         blankTransactionAsync();
  99     }
 100
 101     @Override
 102     public void removedService(ServiceReference<ModuleFactory> moduleFactoryServiceReference, Object o) {
 103         blankTransactionAsync();
 104     }
 105
 106     @VisibleForTesting
 107     interface BlankTransaction {
 108         CommitStatus hit() throws ValidationException, ConflictingVersionException;
 109     }
 110 }