| /* |
| * 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.tephra.hbase.coprocessor; |
| |
| import com.google.common.base.Supplier; |
| import com.google.common.collect.Maps; |
| import com.google.common.collect.Sets; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.hbase.Cell; |
| import org.apache.hadoop.hbase.CellUtil; |
| import org.apache.hadoop.hbase.CoprocessorEnvironment; |
| import org.apache.hadoop.hbase.HColumnDescriptor; |
| import org.apache.hadoop.hbase.HConstants; |
| import org.apache.hadoop.hbase.HTableDescriptor; |
| import org.apache.hadoop.hbase.client.Delete; |
| import org.apache.hadoop.hbase.client.Durability; |
| import org.apache.hadoop.hbase.client.Get; |
| import org.apache.hadoop.hbase.client.OperationWithAttributes; |
| import org.apache.hadoop.hbase.client.Put; |
| import org.apache.hadoop.hbase.client.Scan; |
| import org.apache.hadoop.hbase.coprocessor.BaseRegionObserver; |
| import org.apache.hadoop.hbase.coprocessor.ObserverContext; |
| import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment; |
| import org.apache.hadoop.hbase.filter.Filter; |
| import org.apache.hadoop.hbase.filter.FilterBase; |
| import org.apache.hadoop.hbase.regionserver.InternalScanner; |
| import org.apache.hadoop.hbase.regionserver.KeyValueScanner; |
| import org.apache.hadoop.hbase.regionserver.RegionScanner; |
| import org.apache.hadoop.hbase.regionserver.ScanType; |
| import org.apache.hadoop.hbase.regionserver.Store; |
| import org.apache.hadoop.hbase.regionserver.StoreScanner; |
| import org.apache.hadoop.hbase.regionserver.compactions.CompactionRequest; |
| import org.apache.hadoop.hbase.regionserver.wal.WALEdit; |
| import org.apache.hadoop.hbase.util.Bytes; |
| import org.apache.tephra.Transaction; |
| import org.apache.tephra.TransactionCodec; |
| import org.apache.tephra.TxConstants; |
| import org.apache.tephra.coprocessor.TransactionStateCache; |
| import org.apache.tephra.coprocessor.TransactionStateCacheSupplier; |
| import org.apache.tephra.persist.TransactionVisibilityState; |
| import org.apache.tephra.util.TxUtils; |
| |
| import java.io.IOException; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.NavigableSet; |
| import java.util.Set; |
| |
| /** |
| * {@code org.apache.hadoop.hbase.coprocessor.RegionObserver} coprocessor that handles server-side processing |
| * for transactions: |
| * <ul> |
| * <li>applies filtering to exclude data from invalid and in-progress transactions</li> |
| * <li>overrides the scanner returned for flush and compaction to drop data written by invalidated transactions, |
| * or expired due to TTL.</li> |
| * </ul> |
| * |
| * <p>In order to use this coprocessor for transactions, configure the class on any table involved in transactions, |
| * or on all user tables by adding the following to hbase-site.xml: |
| * {@code |
| * <property> |
| * <name>hbase.coprocessor.region.classes</name> |
| * <value>org.apache.tephra.hbase.coprocessor.TransactionProcessor</value> |
| * </property> |
| * } |
| * </p> |
| * |
| * <p>HBase {@code Get} and {@code Scan} operations should have the current transaction serialized on to the operation |
| * as an attribute: |
| * {@code |
| * Transaction t = ...; |
| * Get get = new Get(...); |
| * TransactionCodec codec = new TransactionCodec(); |
| * codec.addToOperation(get, t); |
| * } |
| * </p> |
| */ |
| public class TransactionProcessor extends BaseRegionObserver { |
| private static final Log LOG = LogFactory.getLog(TransactionProcessor.class); |
| |
| private TransactionStateCache cache; |
| private final TransactionCodec txCodec; |
| protected Map<byte[], Long> ttlByFamily = Maps.newTreeMap(Bytes.BYTES_COMPARATOR); |
| protected boolean allowEmptyValues = TxConstants.ALLOW_EMPTY_VALUES_DEFAULT; |
| protected boolean readNonTxnData = TxConstants.DEFAULT_READ_NON_TX_DATA; |
| |
| public TransactionProcessor() { |
| this.txCodec = new TransactionCodec(); |
| } |
| |
| /* RegionObserver implementation */ |
| |
| @Override |
| public void start(CoprocessorEnvironment e) throws IOException { |
| if (e instanceof RegionCoprocessorEnvironment) { |
| RegionCoprocessorEnvironment env = (RegionCoprocessorEnvironment) e; |
| Supplier<TransactionStateCache> cacheSupplier = getTransactionStateCacheSupplier(env); |
| this.cache = cacheSupplier.get(); |
| |
| HTableDescriptor tableDesc = env.getRegion().getTableDesc(); |
| for (HColumnDescriptor columnDesc : tableDesc.getFamilies()) { |
| String columnTTL = columnDesc.getValue(TxConstants.PROPERTY_TTL); |
| long ttl = 0; |
| if (columnTTL != null) { |
| try { |
| ttl = Long.parseLong(columnTTL); |
| LOG.info("Family " + columnDesc.getNameAsString() + " has TTL of " + columnTTL); |
| } catch (NumberFormatException nfe) { |
| LOG.warn("Invalid TTL value configured for column family " + columnDesc.getNameAsString() + |
| ", value = " + columnTTL); |
| } |
| } |
| ttlByFamily.put(columnDesc.getName(), ttl); |
| } |
| |
| this.allowEmptyValues = env.getConfiguration().getBoolean(TxConstants.ALLOW_EMPTY_VALUES_KEY, |
| TxConstants.ALLOW_EMPTY_VALUES_DEFAULT); |
| this.readNonTxnData = Boolean.valueOf(tableDesc.getValue(TxConstants.READ_NON_TX_DATA)); |
| if (readNonTxnData) { |
| LOG.info("Reading pre-existing data enabled for table " + tableDesc.getNameAsString()); |
| } |
| } |
| } |
| |
| protected Supplier<TransactionStateCache> getTransactionStateCacheSupplier(RegionCoprocessorEnvironment env) { |
| return new TransactionStateCacheSupplier(env.getConfiguration()); |
| } |
| |
| @Override |
| public void stop(CoprocessorEnvironment e) throws IOException { |
| // nothing to do |
| } |
| |
| @Override |
| public void preGetOp(ObserverContext<RegionCoprocessorEnvironment> e, Get get, List<Cell> results) |
| throws IOException { |
| Transaction tx = getFromOperation(get); |
| if (tx != null) { |
| projectFamilyDeletes(get); |
| get.setMaxVersions(); |
| get.setTimeRange(TxUtils.getOldestVisibleTimestamp(ttlByFamily, tx, readNonTxnData), |
| TxUtils.getMaxVisibleTimestamp(tx)); |
| Filter newFilter = getTransactionFilter(tx, ScanType.USER_SCAN, get.getFilter()); |
| get.setFilter(newFilter); |
| } |
| } |
| |
| @Override |
| public void preDelete(ObserverContext<RegionCoprocessorEnvironment> e, Delete delete, WALEdit edit, |
| Durability durability) throws IOException { |
| // Translate deletes into our own delete tombstones |
| // Since HBase deletes cannot be undone, we need to translate deletes into special puts, which allows |
| // us to rollback the changes (by a real delete) if the transaction fails |
| |
| // Deletes that are part of a transaction rollback do not need special handling. |
| // They will never be rolled back, so are performed as normal HBase deletes. |
| if (isRollbackOperation(delete)) { |
| return; |
| } |
| |
| // Other deletes are client-initiated and need to be translated into our own tombstones |
| // TODO: this should delegate to the DeleteStrategy implementation. |
| Put deleteMarkers = new Put(delete.getRow(), delete.getTimeStamp()); |
| for (byte[] family : delete.getFamilyCellMap().keySet()) { |
| List<Cell> familyCells = delete.getFamilyCellMap().get(family); |
| if (isFamilyDelete(familyCells)) { |
| deleteMarkers.add(family, TxConstants.FAMILY_DELETE_QUALIFIER, familyCells.get(0).getTimestamp(), |
| HConstants.EMPTY_BYTE_ARRAY); |
| } else { |
| int cellSize = familyCells.size(); |
| for (int i = 0; i < cellSize; i++) { |
| Cell cell = familyCells.get(i); |
| deleteMarkers.add(family, CellUtil.cloneQualifier(cell), cell.getTimestamp(), |
| HConstants.EMPTY_BYTE_ARRAY); |
| } |
| } |
| } |
| for (Map.Entry<String, byte[]> entry : delete.getAttributesMap().entrySet()) { |
| deleteMarkers.setAttribute(entry.getKey(), entry.getValue()); |
| } |
| e.getEnvironment().getRegion().put(deleteMarkers); |
| // skip normal delete handling |
| e.bypass(); |
| } |
| |
| private boolean isFamilyDelete(List<Cell> familyCells) { |
| return familyCells.size() == 1 && CellUtil.isDeleteFamily(familyCells.get(0)); |
| } |
| |
| @Override |
| public RegionScanner preScannerOpen(ObserverContext<RegionCoprocessorEnvironment> e, Scan scan, RegionScanner s) |
| throws IOException { |
| Transaction tx = getFromOperation(scan); |
| if (tx != null) { |
| projectFamilyDeletes(scan); |
| scan.setMaxVersions(); |
| scan.setTimeRange(TxUtils.getOldestVisibleTimestamp(ttlByFamily, tx, readNonTxnData), |
| TxUtils.getMaxVisibleTimestamp(tx)); |
| Filter newFilter = getTransactionFilter(tx, ScanType.USER_SCAN, scan.getFilter()); |
| scan.setFilter(newFilter); |
| } |
| return s; |
| } |
| |
| /** |
| * Ensures that family delete markers are present in the columns requested for any scan operation. |
| * @param scan The original scan request |
| * @return The modified scan request with the family delete qualifiers represented |
| */ |
| private Scan projectFamilyDeletes(Scan scan) { |
| for (Map.Entry<byte[], NavigableSet<byte[]>> entry : scan.getFamilyMap().entrySet()) { |
| NavigableSet<byte[]> columns = entry.getValue(); |
| // wildcard scans will automatically include the delete marker, so only need to add it when we have |
| // explicit columns listed |
| if (columns != null && !columns.isEmpty()) { |
| scan.addColumn(entry.getKey(), TxConstants.FAMILY_DELETE_QUALIFIER); |
| } |
| } |
| return scan; |
| } |
| |
| /** |
| * Ensures that family delete markers are present in the columns requested for any get operation. |
| * @param get The original get request |
| * @return The modified get request with the family delete qualifiers represented |
| */ |
| private Get projectFamilyDeletes(Get get) { |
| for (Map.Entry<byte[], NavigableSet<byte[]>> entry : get.getFamilyMap().entrySet()) { |
| NavigableSet<byte[]> columns = entry.getValue(); |
| // wildcard scans will automatically include the delete marker, so only need to add it when we have |
| // explicit columns listed |
| if (columns != null && !columns.isEmpty()) { |
| get.addColumn(entry.getKey(), TxConstants.FAMILY_DELETE_QUALIFIER); |
| } |
| } |
| return get; |
| } |
| |
| @Override |
| public InternalScanner preFlushScannerOpen(ObserverContext<RegionCoprocessorEnvironment> c, Store store, |
| KeyValueScanner memstoreScanner, InternalScanner scanner) |
| throws IOException { |
| return createStoreScanner(c.getEnvironment(), "flush", cache.getLatestState(), store, |
| Collections.singletonList(memstoreScanner), ScanType.COMPACT_RETAIN_DELETES, |
| HConstants.OLDEST_TIMESTAMP); |
| } |
| |
| @Override |
| public InternalScanner preCompactScannerOpen(ObserverContext<RegionCoprocessorEnvironment> c, Store store, |
| List<? extends KeyValueScanner> scanners, ScanType scanType, long earliestPutTs, InternalScanner s, |
| CompactionRequest request) |
| throws IOException { |
| return createStoreScanner(c.getEnvironment(), "compaction", cache.getLatestState(), store, scanners, |
| scanType, earliestPutTs); |
| } |
| |
| protected InternalScanner createStoreScanner(RegionCoprocessorEnvironment env, String action, |
| TransactionVisibilityState snapshot, Store store, |
| List<? extends KeyValueScanner> scanners, ScanType type, |
| long earliestPutTs) throws IOException { |
| if (snapshot == null) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Region " + env.getRegion().getRegionNameAsString() + |
| ", no current transaction state found, defaulting to normal " + action + " scanner"); |
| } |
| return null; |
| } |
| |
| // construct a dummy transaction from the latest snapshot |
| Transaction dummyTx = TxUtils.createDummyTransaction(snapshot); |
| Scan scan = new Scan(); |
| // need to see all versions, since we filter out excludes and applications may rely on multiple versions |
| scan.setMaxVersions(); |
| scan.setFilter( |
| new IncludeInProgressFilter(dummyTx.getVisibilityUpperBound(), |
| snapshot.getInvalid(), |
| getTransactionFilter(dummyTx, type, null))); |
| |
| return new StoreScanner(store, store.getScanInfo(), scan, scanners, |
| type, store.getSmallestReadPoint(), earliestPutTs); |
| } |
| |
| private Transaction getFromOperation(OperationWithAttributes op) throws IOException { |
| byte[] encoded = op.getAttribute(TxConstants.TX_OPERATION_ATTRIBUTE_KEY); |
| if (encoded == null) { |
| // to support old clients |
| encoded = op.getAttribute(TxConstants.OLD_TX_OPERATION_ATTRIBUTE_KEY); |
| } |
| if (encoded != null) { |
| return txCodec.decode(encoded); |
| } |
| return null; |
| } |
| |
| private boolean isRollbackOperation(OperationWithAttributes op) throws IOException { |
| return op.getAttribute(TxConstants.TX_ROLLBACK_ATTRIBUTE_KEY) != null || |
| // to support old clients |
| op.getAttribute(TxConstants.OLD_TX_ROLLBACK_ATTRIBUTE_KEY) != null; |
| } |
| |
| /** |
| * Derived classes can override this method to customize the filter used to return data visible for the current |
| * transaction. |
| * |
| * @param tx the current transaction to apply |
| * @param type the type of scan being performed |
| */ |
| protected Filter getTransactionFilter(Transaction tx, ScanType type, Filter filter) { |
| return TransactionFilters.getVisibilityFilter(tx, ttlByFamily, allowEmptyValues, type, filter); |
| } |
| |
| /** |
| * Filter used to include cells visible to in-progress transactions on flush and commit. |
| */ |
| static class IncludeInProgressFilter extends FilterBase { |
| private final long visibilityUpperBound; |
| private final Set<Long> invalidIds; |
| private final Filter txFilter; |
| |
| public IncludeInProgressFilter(long upperBound, Collection<Long> invalids, Filter transactionFilter) { |
| this.visibilityUpperBound = upperBound; |
| this.invalidIds = Sets.newHashSet(invalids); |
| this.txFilter = transactionFilter; |
| } |
| |
| @Override |
| public ReturnCode filterKeyValue(Cell cell) throws IOException { |
| // include all cells visible to in-progress transactions, except for those already marked as invalid |
| long ts = cell.getTimestamp(); |
| if (ts > visibilityUpperBound) { |
| // include everything that could still be in-progress except invalids |
| if (invalidIds.contains(ts)) { |
| return ReturnCode.SKIP; |
| } |
| return ReturnCode.INCLUDE; |
| } |
| return txFilter.filterKeyValue(cell); |
| } |
| } |
| } |
