hwvtepsouthbound/hwvtepsouthbound-impl/src/main/java/org/opendaylight/ovsdb/hwvtepsouthbound/transactions/md/TransactionInvokerImpl.java

   1 /*
   2  * Copyright (c) 2015 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
   9 package org.opendaylight.ovsdb.hwvtepsouthbound.transactions.md;
  10
  11 import java.util.ArrayList;
  12 import java.util.HashMap;
  13 import java.util.List;
  14 import java.util.Map;
  15 import java.util.concurrent.BlockingQueue;
  16 import java.util.concurrent.ExecutorService;
  17 import java.util.concurrent.Executors;
  18 import java.util.concurrent.LinkedBlockingQueue;
  19 import java.util.concurrent.ThreadFactory;
  20
  21 import org.opendaylight.controller.md.sal.binding.api.BindingTransactionChain;
  22 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
  23 import org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction;
  24 import org.opendaylight.controller.md.sal.common.api.data.AsyncTransaction;
  25 import org.opendaylight.controller.md.sal.common.api.data.TransactionChain;
  26 import org.opendaylight.controller.md.sal.common.api.data.TransactionChainListener;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 import com.google.common.util.concurrent.FutureCallback;
  31 import com.google.common.util.concurrent.Futures;
  32 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  33
  34 /*  TODO:
  35  * Copied over as-is from southbound plugin. Good candidate to be common
  36  * when refactoring code.
  37  */
  38 public class TransactionInvokerImpl implements TransactionInvoker,TransactionChainListener, Runnable, AutoCloseable {
  39     private static final Logger LOG = LoggerFactory.getLogger(TransactionInvokerImpl.class);
  40     private static final int QUEUE_SIZE = 10000;
  41     private BindingTransactionChain chain;
  42     private DataBroker db;
  43     private BlockingQueue<TransactionCommand> inputQueue = new LinkedBlockingQueue<>(QUEUE_SIZE);
  44     private BlockingQueue<ReadWriteTransaction> successfulTransactionQueue
  45         = new LinkedBlockingQueue<>(QUEUE_SIZE);
  46     private BlockingQueue<AsyncTransaction<?, ?>> failedTransactionQueue
  47         = new LinkedBlockingQueue<>(QUEUE_SIZE);
  48     private ExecutorService executor;
  49     private Map<ReadWriteTransaction,TransactionCommand> transactionToCommand
  50         = new HashMap<>();
  51     private List<ReadWriteTransaction> pendingTransactions = new ArrayList<>();
  52
  53     public TransactionInvokerImpl(DataBroker db) {
  54         this.db = db;
  55         this.chain = db.createTransactionChain(this);
  56         ThreadFactory threadFact = new ThreadFactoryBuilder().setNameFormat("transaction-invoker-impl-%d").build();
  57         executor = Executors.newSingleThreadExecutor(threadFact);
  58         executor.submit(this);
  59     }
  60
  61     @Override
  62     public void invoke(final TransactionCommand command) {
  63         // TODO what do we do if queue is full?
  64         inputQueue.offer(command);
  65     }
  66
  67     @Override
  68     public void onTransactionChainFailed(TransactionChain<?, ?> chain,
  69             AsyncTransaction<?, ?> transaction, Throwable cause) {
  70         failedTransactionQueue.offer(transaction);
  71     }
  72
  73     @Override
  74     public void onTransactionChainSuccessful(TransactionChain<?, ?> chain) {
  75         // NO OP
  76
  77     }
  78
  79     @Override
  80     public void run() {
  81         while (true) {
  82             forgetSuccessfulTransactions();
  83             try {
  84                 List<TransactionCommand> commands = extractCommands();
  85                 for (TransactionCommand command: commands) {
  86                     final ReadWriteTransaction transaction = chain.newReadWriteTransaction();
  87                     recordPendingTransaction(command, transaction);
  88                     command.execute(transaction);
  89                     Futures.addCallback(transaction.submit(), new FutureCallback<Void>() {
  90                         @Override
  91                         public void onSuccess(final Void result) {
  92                             successfulTransactionQueue.offer(transaction);
  93                         }
  94
  95                         @Override
  96                         public void onFailure(final Throwable throwable) {
  97                             // NOOP - handled by failure of transaction chain
  98                         }
  99                     });
 100                 }
 101             } catch (Exception e) {
 102                 LOG.warn("Exception invoking Transaction: ", e);
 103             }
 104         }
 105     }
 106
 107     private List<TransactionCommand> extractResubmitCommands() {
 108         AsyncTransaction<?, ?> transaction = failedTransactionQueue.poll();
 109         List<TransactionCommand> commands = new ArrayList<>();
 110         if (transaction != null) {
 111             int index = pendingTransactions.lastIndexOf(transaction);
 112             List<ReadWriteTransaction> transactions =
 113                     pendingTransactions.subList(index, pendingTransactions.size() - 1);
 114             for (ReadWriteTransaction tx: transactions) {
 115                 commands.add(transactionToCommand.get(tx));
 116             }
 117             resetTransactionQueue();
 118         }
 119         return commands;
 120     }
 121
 122     private void resetTransactionQueue() {
 123         chain.close();
 124         chain = db.createTransactionChain(this);
 125         pendingTransactions = new ArrayList<>();
 126         transactionToCommand = new HashMap<>();
 127         failedTransactionQueue.clear();
 128         successfulTransactionQueue.clear();
 129     }
 130
 131     private void recordPendingTransaction(TransactionCommand command,
 132             final ReadWriteTransaction transaction) {
 133         transactionToCommand.put(transaction, command);
 134         pendingTransactions.add(transaction);
 135     }
 136
 137     private List<TransactionCommand> extractCommands() throws InterruptedException {
 138         List<TransactionCommand> commands = extractResubmitCommands();
 139         commands.addAll(extractCommandsFromQueue());
 140         return commands;
 141     }
 142
 143     private List<TransactionCommand> extractCommandsFromQueue() throws InterruptedException {
 144         List<TransactionCommand> result = new ArrayList<>();
 145         TransactionCommand command = inputQueue.take();
 146         while (command != null) {
 147             result.add(command);
 148             command = inputQueue.poll();
 149         }
 150         return result;
 151     }
 152
 153     private void forgetSuccessfulTransactions() {
 154         ReadWriteTransaction transaction = successfulTransactionQueue.poll();
 155         while (transaction != null) {
 156             pendingTransactions.remove(transaction);
 157             transactionToCommand.remove(transaction);
 158             transaction = successfulTransactionQueue.poll();
 159         }
 160     }
 161
 162     @Override
 163     public void close() throws Exception {
 164         this.executor.shutdown();
 165     }
 166 }