/gemfire-core/src/main/java/com/gemstone/gemfire/cache/client/internal/DestroyOp.java

/*=========================================================================
 * Copyright (c) 2002-2014 Pivotal Software, Inc. All Rights Reserved.
 * This product is protected by U.S. and international copyright
 * and intellectual property laws. Pivotal products are covered by
 * more patents listed at http://www.pivotal.io/patents.
 *=========================================================================
 */
package com.gemstone.gemfire.cache.client.internal;

import org.apache.logging.log4j.Logger;

import com.gemstone.gemfire.cache.CacheClosedException;
import com.gemstone.gemfire.cache.EntryNotFoundException;
import com.gemstone.gemfire.cache.Operation;
import com.gemstone.gemfire.cache.client.AllConnectionsInUseException;
import com.gemstone.gemfire.cache.client.ServerConnectivityException;
import com.gemstone.gemfire.cache.client.ServerOperationException;
import com.gemstone.gemfire.cache.util.BridgeWriterException;
import com.gemstone.gemfire.distributed.internal.ServerLocation;
import com.gemstone.gemfire.distributed.internal.membership.InternalDistributedMember;
import com.gemstone.gemfire.internal.cache.EntryEventImpl;
import com.gemstone.gemfire.internal.cache.LocalRegion;
import com.gemstone.gemfire.internal.cache.tier.MessageType;
import com.gemstone.gemfire.internal.cache.tier.sockets.Message;
import com.gemstone.gemfire.internal.cache.tier.sockets.Part;
import com.gemstone.gemfire.internal.cache.versions.VersionTag;
import com.gemstone.gemfire.internal.i18n.LocalizedStrings;
import com.gemstone.gemfire.internal.logging.LogService;

/**
 * Does a region destroy on a server
 * @author darrel
 * @since 5.7
 */
public class DestroyOp {

  private static final Logger logger = LogService.getLogger();
  
  public static final int HAS_VERSION_TAG = 0x01;
  
  public static final int HAS_ENTRY_NOT_FOUND_PART = 0x02;

  /**
   * Does a region entry destroy on a server using connections from the given pool
   * to communicate with the server.
   * @param pool the pool to use to communicate with the server.
   * @param region the region to do the entry destroy on
   * @param key the entry key to do the destroy on
   * @param event the event for this destroy operation
   * @param callbackArg an optional callback arg to pass to any cache callbacks
   */
  public static Object execute(ExecutablePool pool, LocalRegion region,
      Object key,
      Object expectedOldValue, Operation operation,
      EntryEventImpl event, Object callbackArg,
      boolean prSingleHopEnabled) {
    if (logger.isDebugEnabled()) {
      logger.debug("Preparing DestroyOp for {} operation={}", key, operation);
    }
    AbstractOp op = new DestroyOpImpl(region, key, expectedOldValue,
        operation, event, callbackArg, prSingleHopEnabled);
    if (prSingleHopEnabled) {
      ClientMetadataService cms = region.getCache()
          .getClientMetadataService();
      ServerLocation server = cms.getBucketServerLocation(region,
          Operation.DESTROY, key, null, callbackArg);
      if (server != null) {
        try {
          PoolImpl poolImpl = (PoolImpl)pool;
          boolean onlyUseExistingCnx = ((poolImpl.getMaxConnections() != -1 && poolImpl
              .getConnectionCount() >= poolImpl.getMaxConnections()) ? true
              : false);
          return pool.executeOn(server, op, true, onlyUseExistingCnx);
        }
        catch (AllConnectionsInUseException e) {
        }
        catch (ServerConnectivityException e) {
          if (e instanceof ServerOperationException) {
            throw e; // fixed 44656
          }
          cms.removeBucketServerLocation(server);
        }
        catch (BridgeWriterException e) {
          if (e.getCause() instanceof ServerConnectivityException)
            cms.removeBucketServerLocation(server);
        }
      }
    }
    return pool.execute(op);
  }
  
  /**
   * Does a region entry destroy on a server using the given connection to
   * communicate with the server.
   * 
   * @param con
   *                the connection to use to send to the server
   * @param pool
   *                the pool to use to communicate with the server.
   * @param region
   *                the region to do the entry destroy on
   * @param key
   *                the entry key to do the destroy on
   * @param event
   *                the event for this destroy operation
   * @param callbackArg
   *                an optional callback arg to pass to any cache callbacks
   */
  public static void execute(Connection con,
                             ExecutablePool pool,
                             String region,
                             Object key,
                             Object expectedOldValue,
                             Operation operation,
                             EntryEventImpl event,
                             Object callbackArg)
  {
    AbstractOp op = new DestroyOpImpl(region, key, expectedOldValue,
        operation, event, callbackArg);
    pool.executeOn(con, op);
  }

  /** this is set if a response is received indicating that the entry was not found on the server */
  public static boolean TEST_HOOK_ENTRY_NOT_FOUND;
                                                               
  private DestroyOp() {
    // no instances allowed
  }
  
  private static class DestroyOpImpl extends AbstractOp {
    
    Object key = null;
    
    private LocalRegion region;       

    private Operation operation;

    private boolean prSingleHopEnabled = false;
    
    private Object callbackArg;
    
    private EntryEventImpl event;
    
    /**
     * @throws com.gemstone.gemfire.SerializationException if serialization fails
     */
    public DestroyOpImpl(LocalRegion region,
                         Object key,
                         Object expectedOldValue,
                         Operation operation,
                         EntryEventImpl event,
                         Object callbackArg,
                         boolean prSingleHopEnabled) {
      super(MessageType.DESTROY, callbackArg != null ? 6 : 5);
      this.key = key;
      this.region = region ;
      this.operation = operation;
      this.prSingleHopEnabled = prSingleHopEnabled;
      this.callbackArg = callbackArg ;
      this.event = event;
      getMessage().addStringPart(region.getFullPath());
      getMessage().addStringOrObjPart(key);
      getMessage().addObjPart(expectedOldValue);
      getMessage().addObjPart(operation==Operation.DESTROY? null : operation); // server interprets null as DESTROY
      getMessage().addBytesPart(event.getEventId().calcBytes());
      if (callbackArg != null) {
        getMessage().addObjPart(callbackArg);
      }
    }


    public DestroyOpImpl(String region, Object key, Object expectedOldValue,
        Operation operation, EntryEventImpl event, 
        Object callbackArg) {
      super(MessageType.DESTROY, callbackArg != null ? 6 : 5);
      this.key = key;
      this.event = event;
      getMessage().addStringPart(region);
      getMessage().addStringOrObjPart(key);
      getMessage().addObjPart(expectedOldValue);
      getMessage().addObjPart(operation==Operation.DESTROY? null : operation); // server interprets null as DESTROY
      getMessage().addBytesPart(event.getEventId().calcBytes());
      if (callbackArg != null) {
        getMessage().addObjPart(callbackArg);
      }
    }
    
    @Override
    protected Object processResponse(Message msg) throws Exception {
      throw new UnsupportedOperationException();
    }
    
    
    @Override
    protected Object processResponse(Message msg, Connection con) throws Exception {
      processAck(msg, "destroy");
      boolean isReply = (msg.getMessageType() == MessageType.REPLY);
      int partIdx = 0;
      int flags = 0;
      if (isReply) {
        flags = msg.getPart(partIdx++).getInt();
        if ((flags & HAS_VERSION_TAG) != 0) {
          VersionTag tag = (VersionTag)msg.getPart(partIdx++).getObject();
          // we use the client's ID since we apparently don't track the server's ID in connections
          tag.replaceNullIDs((InternalDistributedMember) con.getEndpoint().getMemberId());
          this.event.setVersionTag(tag);
          if (logger.isDebugEnabled()) {
            logger.debug("received Destroy response with {}", tag);
            }
        } else if (logger.isDebugEnabled()) {
          logger.debug("received Destroy response with no version tag");
        }
      }
      if (prSingleHopEnabled) {
        byte version = 0 ;
//        if (log.fineEnabled()) {
//          log.fine("reading prSingleHop part #" + (partIdx+1));
//        }
        Part part = msg.getPart(partIdx++);
        byte[] bytesReceived = part.getSerializedForm();
        if (bytesReceived[0] != ClientMetadataService.INITIAL_VERSION
            && bytesReceived.length == ClientMetadataService.SIZE_BYTES_ARRAY_RECEIVED) {
          if (this.region != null) {
            ClientMetadataService cms = null;
            try {
              cms = region.getCache().getClientMetadataService();
              version = cms.getMetaDataVersion(region, Operation.UPDATE,
                  key, null, callbackArg);
            }
            catch (CacheClosedException e) {
              return null;
            }
            if (bytesReceived[0] != version) {
              cms.scheduleGetPRMetaData(region, false,bytesReceived[1]);
            }
          }
        }
      } else {
        partIdx++; // skip OK byte
      }
      boolean entryNotFound = false;
      if (msg.getMessageType() == MessageType.REPLY && (flags & HAS_ENTRY_NOT_FOUND_PART) != 0) {
        entryNotFound = (msg.getPart(partIdx++).getInt() == 1);
        if (logger.isDebugEnabled() && (flags & HAS_ENTRY_NOT_FOUND_PART) != 0) {
          logger.debug("destroy response has entryNotFound={}", entryNotFound);
        }
        if (entryNotFound) {
          TEST_HOOK_ENTRY_NOT_FOUND = true;
        }
      }
      if (this.operation == Operation.REMOVE && entryNotFound) {
        if (logger.isDebugEnabled()) {
          logger.debug("received REMOVE response from server with entryNotFound={}", entryNotFound);
        }
        return new EntryNotFoundException(LocalizedStrings.AbstractRegionMap_ENTRY_NOT_FOUND_WITH_EXPECTED_VALUE.toLocalizedString());
      }
      return null;
    }

    @Override
    protected boolean isErrorResponse(int msgType) {
      return msgType == MessageType.DESTROY_DATA_ERROR;
    }

    @Override
    protected long startAttempt(ConnectionStats stats) {
      return stats.startDestroy();
    }
    @Override
    protected void endSendAttempt(ConnectionStats stats, long start) {
      stats.endDestroySend(start, hasFailed());
    }
    @Override
    protected void endAttempt(ConnectionStats stats, long start) {
      stats.endDestroy(start, hasTimedOut(), hasFailed());
    }
    @Override
    public String toString() {
      return "DestroyOp:"+key;
    }
  }
}