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/*
*
* 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.index.internal;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.function.BiFunction;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;
import com.google.common.collect.ImmutableSet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.config.CFMetaData;
import org.apache.cassandra.config.ColumnDefinition;
import org.apache.cassandra.cql3.Operator;
import org.apache.cassandra.cql3.statements.IndexTarget;
import org.apache.cassandra.db.*;
import org.apache.cassandra.db.compaction.CompactionManager;
import org.apache.cassandra.db.filter.RowFilter;
import org.apache.cassandra.db.lifecycle.SSTableSet;
import org.apache.cassandra.db.lifecycle.View;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.db.marshal.CollectionType;
import org.apache.cassandra.db.marshal.EmptyType;
import org.apache.cassandra.db.partitions.PartitionIterator;
import org.apache.cassandra.db.partitions.PartitionUpdate;
import org.apache.cassandra.db.rows.*;
import org.apache.cassandra.dht.LocalPartitioner;
import org.apache.cassandra.exceptions.InvalidRequestException;
import org.apache.cassandra.index.*;
import org.apache.cassandra.index.internal.composites.CompositesSearcher;
import org.apache.cassandra.index.internal.keys.KeysSearcher;
import org.apache.cassandra.index.transactions.IndexTransaction;
import org.apache.cassandra.index.transactions.UpdateTransaction;
import org.apache.cassandra.io.sstable.ReducingKeyIterator;
import org.apache.cassandra.io.sstable.format.SSTableReader;
import org.apache.cassandra.schema.IndexMetadata;
import org.apache.cassandra.utils.FBUtilities;
import org.apache.cassandra.utils.Pair;
import org.apache.cassandra.utils.concurrent.OpOrder;
import org.apache.cassandra.utils.concurrent.Refs;
import static org.apache.cassandra.cql3.statements.RequestValidations.checkFalse;
/**
* Index implementation which indexes the values for a single column in the base
* table and which stores its index data in a local, hidden table.
*/
public abstract class CassandraIndex implements Index
{
private static final Logger logger = LoggerFactory.getLogger(CassandraIndex.class);
public final ColumnFamilyStore baseCfs;
protected IndexMetadata metadata;
protected ColumnFamilyStore indexCfs;
protected ColumnDefinition indexedColumn;
protected CassandraIndexFunctions functions;
protected CassandraIndex(ColumnFamilyStore baseCfs, IndexMetadata indexDef)
{
this.baseCfs = baseCfs;
setMetadata(indexDef);
}
/**
* Returns true if an index of this type can support search predicates of the form [column] OPERATOR [value]
* @param indexedColumn
* @param operator
* @return
*/
protected boolean supportsOperator(ColumnDefinition indexedColumn, Operator operator)
{
return operator == Operator.EQ;
}
/**
* Used to construct an the clustering for an entry in the index table based on values from the base data.
* The clustering columns in the index table encode the values required to retrieve the correct data from the base
* table and varies depending on the kind of the indexed column. See indexCfsMetadata for more details
* Used whenever a row in the index table is written or deleted.
* @param partitionKey from the base data being indexed
* @param prefix from the base data being indexed
* @param path from the base data being indexed
* @return a clustering prefix to be used to insert into the index table
*/
protected abstract CBuilder buildIndexClusteringPrefix(ByteBuffer partitionKey,
ClusteringPrefix prefix,
CellPath path);
/**
* Used at search time to convert a row in the index table into a simple struct containing the values required
* to retrieve the corresponding row from the base table.
* @param indexedValue the partition key of the indexed table (i.e. the value that was indexed)
* @param indexEntry a row from the index table
* @return
*/
public abstract IndexEntry decodeEntry(DecoratedKey indexedValue,
Row indexEntry);
/**
* Check whether a value retrieved from an index is still valid by comparing it to current row from the base table.
* Used at read time to identify out of date index entries so that they can be excluded from search results and
* repaired
* @param row the current row from the primary data table
* @param indexValue the value we retrieved from the index
* @param nowInSec
* @return true if the index is out of date and the entry should be dropped
*/
public abstract boolean isStale(Row row, ByteBuffer indexValue, int nowInSec);
/**
* Extract the value to be inserted into the index from the components of the base data
* @param partitionKey from the primary data
* @param clustering from the primary data
* @param path from the primary data
* @param cellValue from the primary data
* @return a ByteBuffer containing the value to be inserted in the index. This will be used to make the partition
* key in the index table
*/
protected abstract ByteBuffer getIndexedValue(ByteBuffer partitionKey,
Clustering clustering,
CellPath path,
ByteBuffer cellValue);
public ColumnDefinition getIndexedColumn()
{
return indexedColumn;
}
public ClusteringComparator getIndexComparator()
{
return indexCfs.metadata.comparator;
}
public ColumnFamilyStore getIndexCfs()
{
return indexCfs;
}
public void register(IndexRegistry registry)
{
registry.registerIndex(this);
}
public Callable getInitializationTask()
{
// if we're just linking in the index on an already-built index post-restart or if the base
// table is empty we've nothing to do. Otherwise, submit for building via SecondaryIndexBuilder
return isBuilt() || baseCfs.isEmpty() ? null : getBuildIndexTask();
}
public IndexMetadata getIndexMetadata()
{
return metadata;
}
public Optional getBackingTable()
{
return indexCfs == null ? Optional.empty() : Optional.of(indexCfs);
}
public Callable getBlockingFlushTask()
{
return () -> {
indexCfs.forceBlockingFlush();
return null;
};
}
public Callable getInvalidateTask()
{
return () -> {
invalidate();
return null;
};
}
public Callable getMetadataReloadTask(IndexMetadata indexDef)
{
return () -> {
indexCfs.metadata.reloadIndexMetadataProperties(baseCfs.metadata);
indexCfs.reload();
return null;
};
}
@Override
public void validate(ReadCommand command) throws InvalidRequestException
{
Optional target = getTargetExpression(command.rowFilter().getExpressions());
if (target.isPresent())
{
ByteBuffer indexValue = target.get().getIndexValue();
checkFalse(indexValue.remaining() > FBUtilities.MAX_UNSIGNED_SHORT,
"Index expression values may not be larger than 64K");
}
}
private void setMetadata(IndexMetadata indexDef)
{
metadata = indexDef;
Pair target = TargetParser.parse(baseCfs.metadata, indexDef);
functions = getFunctions(indexDef, target);
CFMetaData cfm = indexCfsMetadata(baseCfs.metadata, indexDef);
indexCfs = ColumnFamilyStore.createColumnFamilyStore(baseCfs.keyspace,
cfm.cfName,
cfm,
baseCfs.getTracker().loadsstables);
indexedColumn = target.left;
}
public Callable getTruncateTask(final long truncatedAt)
{
return () -> {
indexCfs.discardSSTables(truncatedAt);
return null;
};
}
public boolean shouldBuildBlocking()
{
// built-in indexes are always included in builds initiated from SecondaryIndexManager
return true;
}
public boolean dependsOn(ColumnDefinition column)
{
return indexedColumn.name.equals(column.name);
}
public boolean supportsExpression(ColumnDefinition column, Operator operator)
{
return indexedColumn.name.equals(column.name)
&& supportsOperator(indexedColumn, operator);
}
private boolean supportsExpression(RowFilter.Expression expression)
{
return supportsExpression(expression.column(), expression.operator());
}
public AbstractType customExpressionValueType()
{
return null;
}
public long getEstimatedResultRows()
{
return indexCfs.getMeanColumns();
}
/**
* No post processing of query results, just return them unchanged
*/
public BiFunction postProcessorFor(ReadCommand command)
{
return (partitionIterator, readCommand) -> partitionIterator;
}
public RowFilter getPostIndexQueryFilter(RowFilter filter)
{
return getTargetExpression(filter.getExpressions()).map(filter::without)
.orElse(filter);
}
private Optional getTargetExpression(List expressions)
{
return expressions.stream().filter(this::supportsExpression).findFirst();
}
public Index.Searcher searcherFor(ReadCommand command)
{
Optional target = getTargetExpression(command.rowFilter().getExpressions());
if (target.isPresent())
{
switch (getIndexMetadata().kind)
{
case COMPOSITES:
return new CompositesSearcher(command, target.get(), this);
case KEYS:
return new KeysSearcher(command, target.get(), this);
default:
throw new IllegalStateException(String.format("Unsupported index type %s for index %s on %s",
metadata.kind,
metadata.name,
indexedColumn.name.toString()));
}
}
return null;
}
public void validate(PartitionUpdate update) throws InvalidRequestException
{
switch (indexedColumn.kind)
{
case PARTITION_KEY:
validatePartitionKey(update.partitionKey());
break;
case CLUSTERING:
validateClusterings(update);
break;
case REGULAR:
if (update.columns().regulars.contains(indexedColumn))
validateRows(update);
break;
case STATIC:
if (update.columns().statics.contains(indexedColumn))
validateRows(Collections.singleton(update.staticRow()));
break;
}
}
public Indexer indexerFor(final DecoratedKey key,
final PartitionColumns columns,
final int nowInSec,
final OpOrder.Group opGroup,
final IndexTransaction.Type transactionType)
{
/**
* Indexes on regular and static columns (the non primary-key ones) only care about updates with live
* data for the column they index. In particular, they don't care about having just row or range deletions
* as they don't know how to update the index table unless they know exactly the value that is deleted.
*
* Note that in practice this means that those indexes are only purged of stale entries on compaction,
* when we resolve both the deletion and the prior data it deletes. Of course, such stale entries are also
* filtered on read.
*/
if (!isPrimaryKeyIndex() && !columns.contains(indexedColumn))
return null;
return new Indexer()
{
public void begin()
{
}
public void partitionDelete(DeletionTime deletionTime)
{
}
public void rangeTombstone(RangeTombstone tombstone)
{
}
public void insertRow(Row row)
{
if (row.isStatic() && !indexedColumn.isStatic() && !indexedColumn.isPartitionKey())
return;
if (isPrimaryKeyIndex())
{
indexPrimaryKey(row.clustering(),
getPrimaryKeyIndexLiveness(row),
row.deletion());
}
else
{
if (indexedColumn.isComplex())
indexCells(row.clustering(), row.getComplexColumnData(indexedColumn));
else
indexCell(row.clustering(), row.getCell(indexedColumn));
}
}
public void removeRow(Row row)
{
if (isPrimaryKeyIndex())
return;
if (indexedColumn.isComplex())
removeCells(row.clustering(), row.getComplexColumnData(indexedColumn));
else
removeCell(row.clustering(), row.getCell(indexedColumn));
}
public void updateRow(Row oldRow, Row newRow)
{
assert oldRow.isStatic() == newRow.isStatic();
if (newRow.isStatic() != indexedColumn.isStatic())
return;
if (isPrimaryKeyIndex())
indexPrimaryKey(newRow.clustering(),
newRow.primaryKeyLivenessInfo(),
newRow.deletion());
if (indexedColumn.isComplex())
{
indexCells(newRow.clustering(), newRow.getComplexColumnData(indexedColumn));
removeCells(oldRow.clustering(), oldRow.getComplexColumnData(indexedColumn));
}
else
{
indexCell(newRow.clustering(), newRow.getCell(indexedColumn));
removeCell(oldRow.clustering(), oldRow.getCell(indexedColumn));
}
}
public void finish()
{
}
private void indexCells(Clustering clustering, Iterable cells)
{
if (cells == null)
return;
for (Cell cell : cells)
indexCell(clustering, cell);
}
private void indexCell(Clustering clustering, Cell cell)
{
if (cell == null || !cell.isLive(nowInSec))
return;
insert(key.getKey(),
clustering,
cell,
LivenessInfo.withExpirationTime(cell.timestamp(), cell.ttl(), cell.localDeletionTime()),
opGroup);
}
private void removeCells(Clustering clustering, Iterable cells)
{
if (cells == null)
return;
for (Cell cell : cells)
removeCell(clustering, cell);
}
private void removeCell(Clustering clustering, Cell cell)
{
if (cell == null || !cell.isLive(nowInSec))
return;
delete(key.getKey(), clustering, cell, opGroup, nowInSec);
}
private void indexPrimaryKey(final Clustering clustering,
final LivenessInfo liveness,
final Row.Deletion deletion)
{
if (liveness.timestamp() != LivenessInfo.NO_TIMESTAMP)
insert(key.getKey(), clustering, null, liveness, opGroup);
if (!deletion.isLive())
delete(key.getKey(), clustering, deletion.time(), opGroup);
}
private LivenessInfo getPrimaryKeyIndexLiveness(Row row)
{
long timestamp = row.primaryKeyLivenessInfo().timestamp();
int ttl = row.primaryKeyLivenessInfo().ttl();
for (Cell cell : row.cells())
{
long cellTimestamp = cell.timestamp();
if (cell.isLive(nowInSec))
{
if (cellTimestamp > timestamp)
{
timestamp = cellTimestamp;
ttl = cell.ttl();
}
}
}
return LivenessInfo.create(timestamp, ttl, nowInSec);
}
};
}
/**
* Specific to internal indexes, this is called by a
* searcher when it encounters a stale entry in the index
* @param indexKey the partition key in the index table
* @param indexClustering the clustering in the index table
* @param deletion deletion timestamp etc
* @param opGroup the operation under which to perform the deletion
*/
public void deleteStaleEntry(DecoratedKey indexKey,
Clustering indexClustering,
DeletionTime deletion,
OpOrder.Group opGroup)
{
doDelete(indexKey, indexClustering, deletion, opGroup);
logger.trace("Removed index entry for stale value {}", indexKey);
}
/**
* Called when adding a new entry to the index
*/
private void insert(ByteBuffer rowKey,
Clustering clustering,
Cell cell,
LivenessInfo info,
OpOrder.Group opGroup)
{
DecoratedKey valueKey = getIndexKeyFor(getIndexedValue(rowKey,
clustering,
cell));
Row row = BTreeRow.noCellLiveRow(buildIndexClustering(rowKey, clustering, cell), info);
PartitionUpdate upd = partitionUpdate(valueKey, row);
indexCfs.apply(upd, UpdateTransaction.NO_OP, opGroup, null);
logger.trace("Inserted entry into index for value {}", valueKey);
}
/**
* Called when deleting entries on non-primary key columns
*/
private void delete(ByteBuffer rowKey,
Clustering clustering,
Cell cell,
OpOrder.Group opGroup,
int nowInSec)
{
DecoratedKey valueKey = getIndexKeyFor(getIndexedValue(rowKey,
clustering,
cell));
doDelete(valueKey,
buildIndexClustering(rowKey, clustering, cell),
new DeletionTime(cell.timestamp(), nowInSec),
opGroup);
}
/**
* Called when deleting entries from indexes on primary key columns
*/
private void delete(ByteBuffer rowKey,
Clustering clustering,
DeletionTime deletion,
OpOrder.Group opGroup)
{
DecoratedKey valueKey = getIndexKeyFor(getIndexedValue(rowKey,
clustering,
null));
doDelete(valueKey,
buildIndexClustering(rowKey, clustering, null),
deletion,
opGroup);
}
private void doDelete(DecoratedKey indexKey,
Clustering indexClustering,
DeletionTime deletion,
OpOrder.Group opGroup)
{
Row row = BTreeRow.emptyDeletedRow(indexClustering, Row.Deletion.regular(deletion));
PartitionUpdate upd = partitionUpdate(indexKey, row);
indexCfs.apply(upd, UpdateTransaction.NO_OP, opGroup, null);
logger.trace("Removed index entry for value {}", indexKey);
}
private void validatePartitionKey(DecoratedKey partitionKey) throws InvalidRequestException
{
assert indexedColumn.isPartitionKey();
validateIndexedValue(getIndexedValue(partitionKey.getKey(), null, null));
}
private void validateClusterings(PartitionUpdate update) throws InvalidRequestException
{
assert indexedColumn.isClusteringColumn();
for (Row row : update)
validateIndexedValue(getIndexedValue(null, row.clustering(), null));
}
private void validateRows(Iterable rows)
{
assert !indexedColumn.isPrimaryKeyColumn();
for (Row row : rows)
{
if (indexedColumn.isComplex())
{
ComplexColumnData data = row.getComplexColumnData(indexedColumn);
if (data != null)
{
for (Cell cell : data)
{
validateIndexedValue(getIndexedValue(null, null, cell.path(), cell.value()));
}
}
}
else
{
validateIndexedValue(getIndexedValue(null, null, row.getCell(indexedColumn)));
}
}
}
private void validateIndexedValue(ByteBuffer value)
{
if (value != null && value.remaining() >= FBUtilities.MAX_UNSIGNED_SHORT)
throw new InvalidRequestException(String.format(
"Cannot index value of size %d for index %s on %s.%s(%s) (maximum allowed size=%d)",
value.remaining(),
metadata.name,
baseCfs.metadata.ksName,
baseCfs.metadata.cfName,
indexedColumn.name.toString(),
FBUtilities.MAX_UNSIGNED_SHORT));
}
private ByteBuffer getIndexedValue(ByteBuffer rowKey,
Clustering clustering,
Cell cell)
{
return getIndexedValue(rowKey,
clustering,
cell == null ? null : cell.path(),
cell == null ? null : cell.value()
);
}
private Clustering buildIndexClustering(ByteBuffer rowKey,
Clustering clustering,
Cell cell)
{
return buildIndexClusteringPrefix(rowKey,
clustering,
cell == null ? null : cell.path()).build();
}
private DecoratedKey getIndexKeyFor(ByteBuffer value)
{
return indexCfs.decorateKey(value);
}
private PartitionUpdate partitionUpdate(DecoratedKey valueKey, Row row)
{
return PartitionUpdate.singleRowUpdate(indexCfs.metadata, valueKey, row);
}
private void invalidate()
{
// interrupt in-progress compactions
Collection cfss = Collections.singleton(indexCfs);
CompactionManager.instance.interruptCompactionForCFs(cfss, true);
CompactionManager.instance.waitForCessation(cfss);
Keyspace.writeOrder.awaitNewBarrier();
indexCfs.forceBlockingFlush();
indexCfs.readOrdering.awaitNewBarrier();
indexCfs.invalidate();
}
private boolean isBuilt()
{
return SystemKeyspace.isIndexBuilt(baseCfs.keyspace.getName(), metadata.name);
}
private boolean isPrimaryKeyIndex()
{
return indexedColumn.isPrimaryKeyColumn();
}
private Callable getBuildIndexTask()
{
return () -> {
buildBlocking();
return null;
};
}
private void buildBlocking()
{
baseCfs.forceBlockingFlush();
try (ColumnFamilyStore.RefViewFragment viewFragment = baseCfs.selectAndReference(View.selectFunction(SSTableSet.CANONICAL));
Refs sstables = viewFragment.refs)
{
if (sstables.isEmpty())
{
logger.info("No SSTable data for {}.{} to build index {} from, marking empty index as built",
baseCfs.metadata.ksName,
baseCfs.metadata.cfName,
metadata.name);
baseCfs.indexManager.markIndexBuilt(metadata.name);
return;
}
logger.info("Submitting index build of {} for data in {}",
metadata.name,
getSSTableNames(sstables));
SecondaryIndexBuilder builder = new CollatedViewIndexBuilder(baseCfs,
Collections.singleton(this),
new ReducingKeyIterator(sstables));
Future future = CompactionManager.instance.submitIndexBuild(builder);
FBUtilities.waitOnFuture(future);
indexCfs.forceBlockingFlush();
baseCfs.indexManager.markIndexBuilt(metadata.name);
}
logger.info("Index build of {} complete", metadata.name);
}
private static String getSSTableNames(Collection sstables)
{
return StreamSupport.stream(sstables.spliterator(), false)
.map(SSTableReader::toString)
.collect(Collectors.joining(", "));
}
/**
* Construct the CFMetadata for an index table, the clustering columns in the index table
* vary dependent on the kind of the indexed value.
* @param baseCfsMetadata
* @param indexMetadata
* @return
*/
public static final CFMetaData indexCfsMetadata(CFMetaData baseCfsMetadata, IndexMetadata indexMetadata)
{
Pair target = TargetParser.parse(baseCfsMetadata, indexMetadata);
CassandraIndexFunctions utils = getFunctions(indexMetadata, target);
ColumnDefinition indexedColumn = target.left;
AbstractType indexedValueType = utils.getIndexedValueType(indexedColumn);
// Tables for legacy KEYS indexes are non-compound and dense
CFMetaData.Builder builder = indexMetadata.isKeys()
? CFMetaData.Builder.create(baseCfsMetadata.ksName,
baseCfsMetadata.indexColumnFamilyName(indexMetadata),
true, false, false)
: CFMetaData.Builder.create(baseCfsMetadata.ksName,
baseCfsMetadata.indexColumnFamilyName(indexMetadata));
builder = builder.withId(baseCfsMetadata.cfId)
.withPartitioner(new LocalPartitioner(indexedValueType))
.addPartitionKey(indexedColumn.name, indexedColumn.type)
.addClusteringColumn("partition_key", baseCfsMetadata.partitioner.partitionOrdering());
if (indexMetadata.isKeys())
{
// A dense, compact table for KEYS indexes must have a compact
// value column defined, even though it is never used
CompactTables.DefaultNames names =
CompactTables.defaultNameGenerator(ImmutableSet.of(indexedColumn.name.toString(), "partition_key"));
builder = builder.addRegularColumn(names.defaultCompactValueName(), EmptyType.instance);
}
else
{
// The clustering columns for a table backing a COMPOSITES index are dependent
// on the specific type of index (there are specializations for indexes on collections)
builder = utils.addIndexClusteringColumns(builder, baseCfsMetadata, indexedColumn);
}
return builder.build().reloadIndexMetadataProperties(baseCfsMetadata);
}
/**
* Factory method for new CassandraIndex instances
* @param baseCfs
* @param indexMetadata
* @return
*/
public static CassandraIndex newIndex(ColumnFamilyStore baseCfs, IndexMetadata indexMetadata)
{
return getFunctions(indexMetadata, TargetParser.parse(baseCfs.metadata, indexMetadata)).newIndexInstance(baseCfs, indexMetadata);
}
static CassandraIndexFunctions getFunctions(IndexMetadata indexDef,
Pair target)
{
if (indexDef.isKeys())
return CassandraIndexFunctions.KEYS_INDEX_FUNCTIONS;
ColumnDefinition indexedColumn = target.left;
if (indexedColumn.type.isCollection() && indexedColumn.type.isMultiCell())
{
switch (((CollectionType)indexedColumn.type).kind)
{
case LIST:
return CassandraIndexFunctions.COLLECTION_VALUE_INDEX_FUNCTIONS;
case SET:
return CassandraIndexFunctions.COLLECTION_KEY_INDEX_FUNCTIONS;
case MAP:
switch (target.right)
{
case KEYS:
return CassandraIndexFunctions.COLLECTION_KEY_INDEX_FUNCTIONS;
case KEYS_AND_VALUES:
return CassandraIndexFunctions.COLLECTION_ENTRY_INDEX_FUNCTIONS;
case VALUES:
return CassandraIndexFunctions.COLLECTION_VALUE_INDEX_FUNCTIONS;
}
throw new AssertionError();
}
}
switch (indexedColumn.kind)
{
case CLUSTERING:
return CassandraIndexFunctions.CLUSTERING_COLUMN_INDEX_FUNCTIONS;
case REGULAR:
case STATIC:
return CassandraIndexFunctions.REGULAR_COLUMN_INDEX_FUNCTIONS;
case PARTITION_KEY:
return CassandraIndexFunctions.PARTITION_KEY_INDEX_FUNCTIONS;
//case COMPACT_VALUE:
// return new CompositesIndexOnCompactValue();
}
throw new AssertionError();
}
}
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