opendaylight/config/config-manager/src/main/java/org/opendaylight/controller/config/manager/impl/osgi/BlankTransactionServiceTracker.java

   1 /*
   2  * Copyright (c) 2013, 2017 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
  27  * handle.
  28  */
  29 public class BlankTransactionServiceTracker implements ServiceTrackerCustomizer<ModuleFactory, Object> {
  30     private static final Logger LOG = LoggerFactory.getLogger(BlankTransactionServiceTracker.class);
  31
  32     public static final int DEFAULT_MAX_ATTEMPTS = 10;
  33
  34     private final BlankTransaction blankTransaction;
  35     private final ExecutorService txExecutor;
  36     private final int maxAttempts;
  37
  38     public BlankTransactionServiceTracker(final ConfigRegistryImpl configRegistry) {
  39         this(() -> {
  40             ObjectName tx = configRegistry.beginConfig(true);
  41             return configRegistry.commitConfig(tx);
  42         });
  43     }
  44
  45     public BlankTransactionServiceTracker(final BlankTransaction blankTransaction) {
  46         this(blankTransaction, DEFAULT_MAX_ATTEMPTS, Executors
  47                 .newSingleThreadExecutor(new ThreadFactoryBuilder().setNameFormat("config-blank-txn-%d").build()));
  48     }
  49
  50     @VisibleForTesting
  51     BlankTransactionServiceTracker(final BlankTransaction blankTx, final int maxAttempts,
  52             final ExecutorService txExecutor) {
  53         this.blankTransaction = blankTx;
  54         this.maxAttempts = maxAttempts;
  55         this.txExecutor = txExecutor;
  56     }
  57
  58     @Override
  59     public Object addingService(final ServiceReference<ModuleFactory> moduleFactoryServiceReference) {
  60         blankTransactionAsync();
  61         return null;
  62     }
  63
  64     private void blankTransactionAsync() {
  65         txExecutor.execute(this::blankTransactionSync);
  66     }
  67
  68     void blankTransactionSync() {
  69         // race condition check: config-persister might push new configuration while
  70         // 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 (final ConflictingVersionException e) {
  79                 lastException = e;
  80                 try {
  81                     Thread.sleep(1000);
  82                 } catch (final InterruptedException interruptedException) {
  83                     Thread.currentThread().interrupt();
  84                     LOG.debug("blankTransactionSync was interrupted");
  85                     return;
  86                 }
  87             } catch (final 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(final ServiceReference<ModuleFactory> moduleFactoryServiceReference,
  98             final Object object) {
  99         blankTransactionAsync();
 100     }
 101
 102     @Override
 103     public void removedService(final ServiceReference<ModuleFactory> moduleFactoryServiceReference,
 104             final Object object) {
 105         blankTransactionAsync();
 106     }
 107
 108     @VisibleForTesting
 109     interface BlankTransaction {
 110         CommitStatus hit() throws ValidationException, ConflictingVersionException;
 111     }
 112 }