| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.hbase.client; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.hbase.classification.InterfaceAudience; |
| import org.apache.hadoop.hbase.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hbase.CoprocessorEnvironment; |
| import org.apache.hadoop.hbase.ServerName; |
| import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment; |
| import org.apache.hadoop.hbase.regionserver.HRegionServer; |
| import org.apache.hadoop.hbase.regionserver.RegionServerServices; |
| import org.apache.hadoop.hbase.security.UserProvider; |
| |
| /** |
| * Connection to an HTable from within a Coprocessor. We can do some nice tricks since we know we |
| * are on a regionserver, for instance skipping the full serialization/deserialization of objects |
| * when talking to the server. |
| * <p> |
| * You should not use this class from any client - its an internal class meant for use by the |
| * coprocessor framework. |
| */ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public class CoprocessorHConnection extends ConnectionImplementation { |
| private static final NonceGenerator NO_NONCE_GEN = new NoNonceGenerator(); |
| |
| /** |
| * Create a {@link ClusterConnection} based on the environment in which we are running the |
| * coprocessor. The {@link ClusterConnection} must be externally cleaned up |
| * (we bypass the usual HTable cleanup mechanisms since we own everything). |
| * @param env environment hosting the {@link ClusterConnection} |
| * @return instance of {@link ClusterConnection}. |
| * @throws IOException if we cannot create the connection |
| */ |
| public static ClusterConnection getConnectionForEnvironment(CoprocessorEnvironment env) |
| throws IOException { |
| // this bit is a little hacky - just trying to get it going for the moment |
| if (env instanceof RegionCoprocessorEnvironment) { |
| RegionCoprocessorEnvironment e = (RegionCoprocessorEnvironment) env; |
| RegionServerServices services = e.getRegionServerServices(); |
| if (services instanceof HRegionServer) { |
| return new CoprocessorHConnection((HRegionServer) services); |
| } |
| } |
| return (ClusterConnection) ConnectionFactory.createConnection(env.getConfiguration()); |
| } |
| |
| private final ServerName serverName; |
| private final HRegionServer server; |
| |
| /** |
| * Constructor that uses server configuration |
| * @param server |
| * @throws IOException if we cannot create the connection |
| */ |
| public CoprocessorHConnection(HRegionServer server) throws IOException { |
| this(server.getConfiguration(), server); |
| } |
| |
| /** |
| * Constructor that accepts custom configuration |
| * @param conf |
| * @param server |
| * @throws IOException if we cannot create the connection |
| */ |
| public CoprocessorHConnection(Configuration conf, HRegionServer server) throws IOException { |
| super(conf, null, UserProvider.instantiate(conf).getCurrent()); |
| this.server = server; |
| this.serverName = server.getServerName(); |
| } |
| |
| @Override |
| public org.apache.hadoop.hbase.protobuf.generated.ClientProtos.ClientService.BlockingInterface |
| getClient(ServerName serverName) throws IOException { |
| // client is trying to reach off-server, so we can't do anything special |
| if (!this.serverName.equals(serverName)) { |
| return super.getClient(serverName); |
| } |
| // the client is attempting to write to the same regionserver, we can short-circuit to our |
| // local regionserver |
| return server.getRSRpcServices(); |
| } |
| |
| @Override |
| public NonceGenerator getNonceGenerator() { |
| return NO_NONCE_GEN; // don't use nonces for coprocessor connection |
| } |
| } |