001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.hbase.master.procedure;
020
021import java.io.IOException;
022import java.util.ArrayList;
023import java.util.Arrays;
024import java.util.List;
025
026import org.apache.hadoop.hbase.HBaseIOException;
027import org.apache.hadoop.hbase.TableName;
028import org.apache.hadoop.hbase.TableNotDisabledException;
029import org.apache.hadoop.hbase.TableNotFoundException;
030import org.apache.hadoop.hbase.client.RegionInfo;
031import org.apache.hadoop.hbase.client.RegionInfoBuilder;
032import org.apache.hadoop.hbase.client.RegionReplicaUtil;
033import org.apache.hadoop.hbase.client.TableDescriptor;
034import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
035import org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer;
036import org.apache.hadoop.hbase.util.ModifyRegionUtils;
037import org.apache.yetus.audience.InterfaceAudience;
038import org.slf4j.Logger;
039import org.slf4j.LoggerFactory;
040import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;
041import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
042import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos;
043import org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos;
044import org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.TruncateTableState;
045
046@InterfaceAudience.Private
047public class TruncateTableProcedure
048    extends AbstractStateMachineTableProcedure<TruncateTableState> {
049  private static final Logger LOG = LoggerFactory.getLogger(TruncateTableProcedure.class);
050
051  private boolean preserveSplits;
052  private List<RegionInfo> regions;
053  private TableDescriptor tableDescriptor;
054  private TableName tableName;
055
056  public TruncateTableProcedure() {
057    // Required by the Procedure framework to create the procedure on replay
058    super();
059  }
060
061  public TruncateTableProcedure(final MasterProcedureEnv env, final TableName tableName,
062      boolean preserveSplits)
063  throws HBaseIOException {
064    this(env, tableName, preserveSplits, null);
065  }
066
067  public TruncateTableProcedure(final MasterProcedureEnv env, final TableName tableName,
068      boolean preserveSplits, ProcedurePrepareLatch latch)
069  throws HBaseIOException {
070    super(env, latch);
071    this.tableName = tableName;
072    preflightChecks(env, false);
073    this.preserveSplits = preserveSplits;
074  }
075
076  @Override
077  protected Flow executeFromState(final MasterProcedureEnv env, TruncateTableState state)
078      throws InterruptedException {
079    if (LOG.isTraceEnabled()) {
080      LOG.trace(this + " execute state=" + state);
081    }
082    try {
083      switch (state) {
084        case TRUNCATE_TABLE_PRE_OPERATION:
085          // Verify if we can truncate the table
086          if (!prepareTruncate(env)) {
087            assert isFailed() : "the truncate should have an exception here";
088            return Flow.NO_MORE_STATE;
089          }
090
091          // TODO: Move out... in the acquireLock()
092          LOG.debug("waiting for '" + getTableName() + "' regions in transition");
093          regions = env.getAssignmentManager().getRegionStates().getRegionsOfTable(getTableName());
094          RegionReplicaUtil.removeNonDefaultRegions(regions);
095          assert regions != null && !regions.isEmpty() : "unexpected 0 regions";
096          ProcedureSyncWait.waitRegionInTransition(env, regions);
097
098          // Call coprocessors
099          preTruncate(env);
100
101          //We need to cache table descriptor in the initial stage, so that it's saved within
102          //the procedure stage and can get recovered if the procedure crashes between
103          //TRUNCATE_TABLE_REMOVE_FROM_META and TRUNCATE_TABLE_CREATE_FS_LAYOUT
104          tableDescriptor = env.getMasterServices().getTableDescriptors().get(tableName);
105          setNextState(TruncateTableState.TRUNCATE_TABLE_CLEAR_FS_LAYOUT);
106          break;
107        case TRUNCATE_TABLE_CLEAR_FS_LAYOUT:
108          DeleteTableProcedure.deleteFromFs(env, getTableName(), regions, true);
109          // NOTE: It's very important that we create new HRegions before next state, so that
110          // they get persisted in procedure state before we start using them for anything.
111          // Otherwise, if we create them in next step and master crashes after creating fs
112          // layout but before saving state, region re-created after recovery will have different
113          // regionId(s) and encoded names. That will lead to unwanted regions in FS layout
114          // (which were created before the crash).
115          if (!preserveSplits) {
116            // if we are not preserving splits, generate a new single region
117            regions = Arrays.asList(ModifyRegionUtils.createRegionInfos(tableDescriptor, null));
118          } else {
119            regions = recreateRegionInfo(regions);
120          }
121          setNextState(TruncateTableState.TRUNCATE_TABLE_REMOVE_FROM_META);
122          break;
123        case TRUNCATE_TABLE_REMOVE_FROM_META:
124          List<RegionInfo> originalRegions = env.getAssignmentManager()
125            .getRegionStates().getRegionsOfTable(getTableName());
126          DeleteTableProcedure.deleteFromMeta(env, getTableName(), originalRegions);
127          DeleteTableProcedure.deleteAssignmentState(env, getTableName());
128          setNextState(TruncateTableState.TRUNCATE_TABLE_CREATE_FS_LAYOUT);
129          break;
130        case TRUNCATE_TABLE_CREATE_FS_LAYOUT:
131          DeleteTableProcedure.deleteFromFs(env, getTableName(), regions, true);
132          regions = CreateTableProcedure.createFsLayout(env, tableDescriptor, regions);
133          env.getMasterServices().getTableDescriptors().update(tableDescriptor, true);
134          setNextState(TruncateTableState.TRUNCATE_TABLE_ADD_TO_META);
135          break;
136        case TRUNCATE_TABLE_ADD_TO_META:
137          regions = CreateTableProcedure.addTableToMeta(env, tableDescriptor, regions);
138          setNextState(TruncateTableState.TRUNCATE_TABLE_ASSIGN_REGIONS);
139          break;
140        case TRUNCATE_TABLE_ASSIGN_REGIONS:
141          CreateTableProcedure.setEnablingState(env, getTableName());
142          addChildProcedure(env.getAssignmentManager().createRoundRobinAssignProcedures(regions));
143          setNextState(TruncateTableState.TRUNCATE_TABLE_POST_OPERATION);
144          tableDescriptor = null;
145          regions = null;
146          break;
147        case TRUNCATE_TABLE_POST_OPERATION:
148          CreateTableProcedure.setEnabledState(env, getTableName());
149          postTruncate(env);
150          LOG.debug("truncate '" + getTableName() + "' completed");
151          return Flow.NO_MORE_STATE;
152        default:
153          throw new UnsupportedOperationException("unhandled state=" + state);
154      }
155    } catch (IOException e) {
156      if (isRollbackSupported(state)) {
157        setFailure("master-truncate-table", e);
158      } else {
159        LOG.warn("Retriable error trying to truncate table=" + getTableName()
160          + " state=" + state, e);
161      }
162    }
163    return Flow.HAS_MORE_STATE;
164  }
165
166  @Override
167  protected void rollbackState(final MasterProcedureEnv env, final TruncateTableState state) {
168    if (state == TruncateTableState.TRUNCATE_TABLE_PRE_OPERATION) {
169      // nothing to rollback, pre-truncate is just table-state checks.
170      // We can fail if the table does not exist or is not disabled.
171      // TODO: coprocessor rollback semantic is still undefined.
172      return;
173    }
174
175    // The truncate doesn't have a rollback. The execution will succeed, at some point.
176    throw new UnsupportedOperationException("unhandled state=" + state);
177  }
178
179  @Override
180  protected void completionCleanup(final MasterProcedureEnv env) {
181    releaseSyncLatch();
182  }
183
184  @Override
185  protected boolean isRollbackSupported(final TruncateTableState state) {
186    switch (state) {
187      case TRUNCATE_TABLE_PRE_OPERATION:
188        return true;
189      default:
190        return false;
191    }
192  }
193
194  @Override
195  protected TruncateTableState getState(final int stateId) {
196    return TruncateTableState.forNumber(stateId);
197  }
198
199  @Override
200  protected int getStateId(final TruncateTableState state) {
201    return state.getNumber();
202  }
203
204  @Override
205  protected TruncateTableState getInitialState() {
206    return TruncateTableState.TRUNCATE_TABLE_PRE_OPERATION;
207  }
208
209  @Override
210  protected boolean holdLock(MasterProcedureEnv env) {
211    return true;
212  }
213
214  @Override
215  public TableName getTableName() {
216    return tableName;
217  }
218
219  @Override
220  public TableOperationType getTableOperationType() {
221    return TableOperationType.EDIT;
222  }
223
224  @Override
225  public void toStringClassDetails(StringBuilder sb) {
226    sb.append(getClass().getSimpleName());
227    sb.append(" (table=");
228    sb.append(getTableName());
229    sb.append(" preserveSplits=");
230    sb.append(preserveSplits);
231    sb.append(")");
232  }
233
234  @Override
235  protected void serializeStateData(ProcedureStateSerializer serializer)
236      throws IOException {
237    super.serializeStateData(serializer);
238
239    MasterProcedureProtos.TruncateTableStateData.Builder state =
240      MasterProcedureProtos.TruncateTableStateData.newBuilder()
241        .setUserInfo(MasterProcedureUtil.toProtoUserInfo(getUser()))
242        .setPreserveSplits(preserveSplits);
243    if (tableDescriptor != null) {
244      state.setTableSchema(ProtobufUtil.toTableSchema(tableDescriptor));
245    } else {
246      state.setTableName(ProtobufUtil.toProtoTableName(tableName));
247    }
248    if (regions != null) {
249      for (RegionInfo hri: regions) {
250        state.addRegionInfo(ProtobufUtil.toRegionInfo(hri));
251      }
252    }
253    serializer.serialize(state.build());
254  }
255
256  @Override
257  protected void deserializeStateData(ProcedureStateSerializer serializer)
258      throws IOException {
259    super.deserializeStateData(serializer);
260
261    MasterProcedureProtos.TruncateTableStateData state =
262        serializer.deserialize(MasterProcedureProtos.TruncateTableStateData.class);
263    setUser(MasterProcedureUtil.toUserInfo(state.getUserInfo()));
264    if (state.hasTableSchema()) {
265      tableDescriptor = ProtobufUtil.toTableDescriptor(state.getTableSchema());
266      tableName = tableDescriptor.getTableName();
267    } else {
268      tableName = ProtobufUtil.toTableName(state.getTableName());
269    }
270    preserveSplits = state.getPreserveSplits();
271    if (state.getRegionInfoCount() == 0) {
272      regions = null;
273    } else {
274      regions = new ArrayList<>(state.getRegionInfoCount());
275      for (HBaseProtos.RegionInfo hri: state.getRegionInfoList()) {
276        regions.add(ProtobufUtil.toRegionInfo(hri));
277      }
278    }
279  }
280
281  private static List<RegionInfo> recreateRegionInfo(final List<RegionInfo> regions) {
282    ArrayList<RegionInfo> newRegions = new ArrayList<>(regions.size());
283    for (RegionInfo hri: regions) {
284      newRegions.add(RegionInfoBuilder.newBuilder(hri.getTable())
285          .setStartKey(hri.getStartKey())
286          .setEndKey(hri.getEndKey())
287          .build());
288    }
289    return newRegions;
290  }
291
292  private boolean prepareTruncate(final MasterProcedureEnv env) throws IOException {
293    try {
294      env.getMasterServices().checkTableModifiable(getTableName());
295    } catch (TableNotFoundException|TableNotDisabledException e) {
296      setFailure("master-truncate-table", e);
297      return false;
298    }
299    return true;
300  }
301
302  private boolean preTruncate(final MasterProcedureEnv env)
303      throws IOException, InterruptedException {
304    final MasterCoprocessorHost cpHost = env.getMasterCoprocessorHost();
305    if (cpHost != null) {
306      final TableName tableName = getTableName();
307      cpHost.preTruncateTableAction(tableName, getUser());
308    }
309    return true;
310  }
311
312  private void postTruncate(final MasterProcedureEnv env)
313      throws IOException, InterruptedException {
314    final MasterCoprocessorHost cpHost = env.getMasterCoprocessorHost();
315    if (cpHost != null) {
316      final TableName tableName = getTableName();
317      cpHost.postCompletedTruncateTableAction(tableName, getUser());
318    }
319  }
320
321  @VisibleForTesting
322  RegionInfo getFirstRegionInfo() {
323    if (regions == null || regions.isEmpty()) {
324      return null;
325    }
326    return regions.get(0);
327  }
328}