org.apache.cassandra.db.virtual.GossipInfoTable Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of cassandra-all Show documentation
Show all versions of cassandra-all Show documentation
The Apache Cassandra Project develops a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model.
/*
* 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.cassandra.db.virtual;
import java.util.EnumSet;
import java.util.Map;
import java.util.function.Supplier;
import com.google.common.annotations.VisibleForTesting;
import org.apache.cassandra.db.marshal.InetAddressType;
import org.apache.cassandra.db.marshal.Int32Type;
import org.apache.cassandra.db.marshal.UTF8Type;
import org.apache.cassandra.dht.LocalPartitioner;
import org.apache.cassandra.gms.ApplicationState;
import org.apache.cassandra.gms.EndpointState;
import org.apache.cassandra.gms.Gossiper;
import org.apache.cassandra.gms.VersionedValue;
import org.apache.cassandra.locator.InetAddressAndPort;
import org.apache.cassandra.schema.TableMetadata;
import static org.apache.cassandra.gms.ApplicationState.TOKENS;
/**
* A {@link VirtualTable} that return the Gossip information in tabular format.
*/
final class GossipInfoTable extends AbstractVirtualTable
{
static final String TABLE_NAME = "gossip_info";
static final String TABLE_COMMENT = "lists the gossip information for the cluster";
static final String ADDRESS = "address";
static final String PORT = "port";
static final String HOSTNAME = "hostname";
static final String GENERATION = "generation";
static final String HEARTBEAT = "heartbeat";
static final ApplicationState[] STATES_FOR_VERSIONS = ApplicationState.values();
static final ApplicationState[] STATES_FOR_VALUES;
static
{
EnumSet applicationStates = EnumSet.allOf(ApplicationState.class);
// do not add a column for the ApplicationState.TOKENS value
applicationStates.remove(TOKENS);
STATES_FOR_VALUES = applicationStates.toArray(new ApplicationState[0]);
}
private final Supplier> endpointStateMapSupplier;
/**
* Construct a new {@link GossipInfoTable} for the given {@code keyspace}.
*
* @param keyspace the name of the keyspace
*/
GossipInfoTable(String keyspace)
{
this(keyspace, () -> Gossiper.instance.endpointStateMap);
}
@VisibleForTesting
GossipInfoTable(String keyspace, Supplier> endpointStateMapSupplier)
{
super(buildTableMetadata(keyspace));
this.endpointStateMapSupplier = endpointStateMapSupplier;
}
/**
* {@inheritDoc}
*/
@Override
public DataSet data()
{
SimpleDataSet result = new SimpleDataSet(metadata());
for (Map.Entry entry : endpointStateMapSupplier.get().entrySet())
{
InetAddressAndPort endpoint = entry.getKey();
// we are making a copy of endpoint state as a value of an entry of the returned map
// might be updated on the fly by LoadBroadcaster, and we want to be sure that
// the returned data are capturing a particular point in time
EndpointState localState = new EndpointState(entry.getValue());
SimpleDataSet dataSet = result.row(endpoint.getAddress(), endpoint.getPort())
.column(HOSTNAME, endpoint.getHostName())
.column(GENERATION, getGeneration(localState))
.column(HEARTBEAT, getHeartBeat(localState));
for (ApplicationState state : STATES_FOR_VALUES)
dataSet.column(state.name().toLowerCase(), getValue(localState, state));
for (ApplicationState state : STATES_FOR_VERSIONS)
dataSet.column(state.name().toLowerCase() + "_version", getVersion(localState, state));
}
return result;
}
/**
* Return the heartbeat generation of a given {@link EndpointState} or null if {@code localState} is null.
*
* @param localState a nullable endpoint state
* @return the heartbeat generation if available, null otherwise
*/
private Integer getGeneration(EndpointState localState)
{
return localState == null ? null : localState.getHeartBeatState().getGeneration();
}
/**
* Return the heartbeat version of a given {@link EndpointState} or null if {@code localState} is null.
*
* @param localState a nullable endpoint state
* @return the heartbeat version if available, null otherwise
*/
private Integer getHeartBeat(EndpointState localState)
{
return localState == null ? null : localState.getHeartBeatState().getHeartBeatVersion();
}
/**
* Returns the value from the {@link VersionedValue} of a given {@link ApplicationState key}, or null
* if {@code localState} is null or the {@link VersionedValue} does not exist in the {@link ApplicationState}.
*
* @param localState a nullable endpoint state
* @param key the key to the application state
* @return the value, or null if not available
*/
private String getValue(EndpointState localState, ApplicationState key)
{
VersionedValue value;
return localState == null || (value = localState.getApplicationState(key)) == null ? null : value.value;
}
/**
* Returns the version from the {@link VersionedValue} of a given {@link ApplicationState key}, or null
* if {@code localState} is null or the {@link VersionedValue} does not exist in the {@link ApplicationState}.
*
* @param localState a nullable endpoint state
* @param key the key to the application state
* @return the version, or null if not available
*/
private Integer getVersion(EndpointState localState, ApplicationState key)
{
VersionedValue value;
return localState == null || (value = localState.getApplicationState(key)) == null ? null : value.version;
}
/**
* Builds the {@link TableMetadata} to be provided to the superclass
*
* @param keyspace the name of the keyspace
* @return the TableMetadata class
*/
private static TableMetadata buildTableMetadata(String keyspace)
{
TableMetadata.Builder builder = TableMetadata.builder(keyspace, TABLE_NAME)
.comment(TABLE_COMMENT)
.kind(TableMetadata.Kind.VIRTUAL)
.partitioner(new LocalPartitioner(InetAddressType.instance))
.addPartitionKeyColumn(ADDRESS, InetAddressType.instance)
.addClusteringColumn(PORT, Int32Type.instance)
.addRegularColumn(HOSTNAME, UTF8Type.instance)
.addRegularColumn(GENERATION, Int32Type.instance)
.addRegularColumn(HEARTBEAT, Int32Type.instance);
for (ApplicationState state : STATES_FOR_VALUES)
builder.addRegularColumn(state.name().toLowerCase(), UTF8Type.instance);
for (ApplicationState state : STATES_FOR_VERSIONS)
builder.addRegularColumn(state.name().toLowerCase() + "_version", Int32Type.instance);
return builder.build();
}
}