| /* |
| * 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; |
| |
| |
| import java.util.Locale; |
| |
| import com.carrotsearch.hppc.ObjectIntHashMap; |
| import org.apache.cassandra.locator.Endpoints; |
| import org.apache.cassandra.locator.InOurDc; |
| import org.apache.cassandra.schema.TableMetadata; |
| import org.apache.cassandra.config.DatabaseDescriptor; |
| import org.apache.cassandra.exceptions.InvalidRequestException; |
| import org.apache.cassandra.locator.AbstractReplicationStrategy; |
| import org.apache.cassandra.locator.NetworkTopologyStrategy; |
| import org.apache.cassandra.transport.ProtocolException; |
| |
| import static org.apache.cassandra.locator.Replicas.addToCountPerDc; |
| |
| public enum ConsistencyLevel |
| { |
| ANY (0), |
| ONE (1), |
| TWO (2), |
| THREE (3), |
| QUORUM (4), |
| ALL (5), |
| LOCAL_QUORUM(6, true), |
| EACH_QUORUM (7), |
| SERIAL (8), |
| LOCAL_SERIAL(9, true), |
| LOCAL_ONE (10, true), |
| NODE_LOCAL (11, true); |
| |
| // Used by the binary protocol |
| public final int code; |
| private final boolean isDCLocal; |
| private static final ConsistencyLevel[] codeIdx; |
| static |
| { |
| int maxCode = -1; |
| for (ConsistencyLevel cl : ConsistencyLevel.values()) |
| maxCode = Math.max(maxCode, cl.code); |
| codeIdx = new ConsistencyLevel[maxCode + 1]; |
| for (ConsistencyLevel cl : ConsistencyLevel.values()) |
| { |
| if (codeIdx[cl.code] != null) |
| throw new IllegalStateException("Duplicate code"); |
| codeIdx[cl.code] = cl; |
| } |
| } |
| |
| ConsistencyLevel(int code) |
| { |
| this(code, false); |
| } |
| |
| ConsistencyLevel(int code, boolean isDCLocal) |
| { |
| this.code = code; |
| this.isDCLocal = isDCLocal; |
| } |
| |
| public static ConsistencyLevel fromCode(int code) |
| { |
| if (code < 0 || code >= codeIdx.length) |
| throw new ProtocolException(String.format("Unknown code %d for a consistency level", code)); |
| return codeIdx[code]; |
| } |
| |
| public static ConsistencyLevel fromString(String str) |
| { |
| return valueOf(str.toUpperCase(Locale.US)); |
| } |
| |
| public static int quorumFor(AbstractReplicationStrategy replicationStrategy) |
| { |
| return (replicationStrategy.getReplicationFactor().allReplicas / 2) + 1; |
| } |
| |
| public static int localQuorumFor(AbstractReplicationStrategy replicationStrategy, String dc) |
| { |
| return (replicationStrategy instanceof NetworkTopologyStrategy) |
| ? (((NetworkTopologyStrategy) replicationStrategy).getReplicationFactor(dc).allReplicas / 2) + 1 |
| : quorumFor(replicationStrategy); |
| } |
| |
| public static int localQuorumForOurDc(AbstractReplicationStrategy replicationStrategy) |
| { |
| return localQuorumFor(replicationStrategy, DatabaseDescriptor.getLocalDataCenter()); |
| } |
| |
| public static ObjectIntHashMap<String> eachQuorumForRead(AbstractReplicationStrategy replicationStrategy) |
| { |
| if (replicationStrategy instanceof NetworkTopologyStrategy) |
| { |
| NetworkTopologyStrategy npStrategy = (NetworkTopologyStrategy) replicationStrategy; |
| ObjectIntHashMap<String> perDc = new ObjectIntHashMap<>(((npStrategy.getDatacenters().size() + 1) * 4) / 3); |
| for (String dc : npStrategy.getDatacenters()) |
| perDc.put(dc, ConsistencyLevel.localQuorumFor(replicationStrategy, dc)); |
| return perDc; |
| } |
| else |
| { |
| ObjectIntHashMap<String> perDc = new ObjectIntHashMap<>(1); |
| perDc.put(DatabaseDescriptor.getLocalDataCenter(), quorumFor(replicationStrategy)); |
| return perDc; |
| } |
| } |
| |
| public static ObjectIntHashMap<String> eachQuorumForWrite(AbstractReplicationStrategy replicationStrategy, Endpoints<?> pendingWithDown) |
| { |
| ObjectIntHashMap<String> perDc = eachQuorumForRead(replicationStrategy); |
| addToCountPerDc(perDc, pendingWithDown, 1); |
| return perDc; |
| } |
| |
| public int blockFor(AbstractReplicationStrategy replicationStrategy) |
| { |
| switch (this) |
| { |
| case ONE: |
| case LOCAL_ONE: |
| return 1; |
| case ANY: |
| return 1; |
| case TWO: |
| return 2; |
| case THREE: |
| return 3; |
| case QUORUM: |
| case SERIAL: |
| return quorumFor(replicationStrategy); |
| case ALL: |
| return replicationStrategy.getReplicationFactor().allReplicas; |
| case LOCAL_QUORUM: |
| case LOCAL_SERIAL: |
| return localQuorumForOurDc(replicationStrategy); |
| case EACH_QUORUM: |
| if (replicationStrategy instanceof NetworkTopologyStrategy) |
| { |
| NetworkTopologyStrategy strategy = (NetworkTopologyStrategy) replicationStrategy; |
| int n = 0; |
| for (String dc : strategy.getDatacenters()) |
| n += localQuorumFor(replicationStrategy, dc); |
| return n; |
| } |
| else |
| { |
| return quorumFor(replicationStrategy); |
| } |
| default: |
| throw new UnsupportedOperationException("Invalid consistency level: " + toString()); |
| } |
| } |
| |
| public int blockForWrite(AbstractReplicationStrategy replicationStrategy, Endpoints<?> pending) |
| { |
| assert pending != null; |
| |
| int blockFor = blockFor(replicationStrategy); |
| switch (this) |
| { |
| case ANY: |
| break; |
| case LOCAL_ONE: case LOCAL_QUORUM: case LOCAL_SERIAL: |
| // we will only count local replicas towards our response count, as these queries only care about local guarantees |
| blockFor += pending.count(InOurDc.replicas()); |
| break; |
| case ONE: case TWO: case THREE: |
| case QUORUM: case EACH_QUORUM: |
| case SERIAL: |
| case ALL: |
| blockFor += pending.size(); |
| } |
| return blockFor; |
| } |
| |
| /** |
| * Determine if this consistency level meets or exceeds the consistency requirements of the given cl for the given keyspace |
| * WARNING: this is not locality aware; you cannot safely use this with mixed locality consistency levels (e.g. LOCAL_QUORUM and QUORUM) |
| */ |
| public boolean satisfies(ConsistencyLevel other, AbstractReplicationStrategy replicationStrategy) |
| { |
| return blockFor(replicationStrategy) >= other.blockFor(replicationStrategy); |
| } |
| |
| public boolean isDatacenterLocal() |
| { |
| return isDCLocal; |
| } |
| |
| public void validateForRead() throws InvalidRequestException |
| { |
| switch (this) |
| { |
| case ANY: |
| throw new InvalidRequestException("ANY ConsistencyLevel is only supported for writes"); |
| } |
| } |
| |
| public void validateForWrite() throws InvalidRequestException |
| { |
| switch (this) |
| { |
| case SERIAL: |
| case LOCAL_SERIAL: |
| throw new InvalidRequestException("You must use conditional updates for serializable writes"); |
| } |
| } |
| |
| // This is the same than validateForWrite really, but we include a slightly different error message for SERIAL/LOCAL_SERIAL |
| public void validateForCasCommit(AbstractReplicationStrategy replicationStrategy) throws InvalidRequestException |
| { |
| switch (this) |
| { |
| case EACH_QUORUM: |
| requireNetworkTopologyStrategy(replicationStrategy); |
| break; |
| case SERIAL: |
| case LOCAL_SERIAL: |
| throw new InvalidRequestException(this + " is not supported as conditional update commit consistency. Use ANY if you mean \"make sure it is accepted but I don't care how many replicas commit it for non-SERIAL reads\""); |
| } |
| } |
| |
| public void validateForCas() throws InvalidRequestException |
| { |
| if (!isSerialConsistency()) |
| throw new InvalidRequestException("Invalid consistency for conditional update. Must be one of SERIAL or LOCAL_SERIAL"); |
| } |
| |
| public boolean isSerialConsistency() |
| { |
| return this == SERIAL || this == LOCAL_SERIAL; |
| } |
| |
| public void validateCounterForWrite(TableMetadata metadata) throws InvalidRequestException |
| { |
| if (this == ConsistencyLevel.ANY) |
| throw new InvalidRequestException("Consistency level ANY is not yet supported for counter table " + metadata.name); |
| |
| if (isSerialConsistency()) |
| throw new InvalidRequestException("Counter operations are inherently non-serializable"); |
| } |
| |
| /** |
| * With a replication factor greater than one, reads that contact more than one replica will require |
| * reconciliation of the individual replica results at the coordinator. |
| * |
| * @return true if reads at this consistency level require merging at the coordinator |
| */ |
| public boolean needsReconciliation() |
| { |
| return this != ConsistencyLevel.ONE && this != ConsistencyLevel.LOCAL_ONE && this != ConsistencyLevel.NODE_LOCAL; |
| } |
| |
| private void requireNetworkTopologyStrategy(AbstractReplicationStrategy replicationStrategy) throws InvalidRequestException |
| { |
| if (!(replicationStrategy instanceof NetworkTopologyStrategy)) |
| throw new InvalidRequestException(String.format("consistency level %s not compatible with replication strategy (%s)", |
| this, replicationStrategy.getClass().getName())); |
| } |
| } |