/* * 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.io.IOException; import java.nio.ByteBuffer; import java.util.*; import com.google.common.collect.Iterables; import com.google.common.collect.MapDifference; import com.google.common.collect.Maps; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.cassandra.config.CFMetaData; import org.apache.cassandra.config.DatabaseDescriptor; import org.apache.cassandra.config.KSMetaData; import org.apache.cassandra.config.Schema; import org.apache.cassandra.db.compaction.CompactionManager; import org.apache.cassandra.db.filter.QueryFilter; import org.apache.cassandra.db.marshal.AsciiType; import org.apache.cassandra.db.marshal.UTF8Type; import org.apache.cassandra.exceptions.ConfigurationException; import org.apache.cassandra.service.MigrationManager; import org.apache.cassandra.service.StorageService; import org.apache.cassandra.utils.ByteBufferUtil; /** * SCHEMA_{KEYSPACES, COLUMNFAMILIES, COLUMNS}_CF are used to store Keyspace/ColumnFamily attributes to make schema * load/distribution easy, it replaces old mechanism when local migrations where serialized, stored in system.Migrations * and used for schema distribution. * * SCHEMA_KEYSPACES_CF layout: * * <key (AsciiType)> * ascii => json_serialized_value * ... * </key> * * Where <key> is a name of keyspace e.g. "ks". * * SCHEMA_COLUMNFAMILIES_CF layout: * * <key (AsciiType)> * composite(ascii, ascii) => json_serialized_value * </key> * * Where <key> is a name of keyspace e.g. "ks"., first component of the column name is name of the ColumnFamily, last * component is the name of the ColumnFamily attribute. * * SCHEMA_COLUMNS_CF layout: * * <key (AsciiType)> * composite(ascii, ascii, ascii) => json_serialized value * </key> * * Where <key> is a name of keyspace e.g. "ks". * * Column names where made composite to support 3-level nesting which represents following structure: * "ColumnFamily name":"column name":"column attribute" => "value" * * Example of schema (using CLI): * * schema_keyspaces * ---------------- * RowKey: ks * => (column=durable_writes, value=true, timestamp=1327061028312185000) * => (column=name, value="ks", timestamp=1327061028312185000) * => (column=replication_factor, value=0, timestamp=1327061028312185000) * => (column=strategy_class, value="org.apache.cassandra.locator.NetworkTopologyStrategy", timestamp=1327061028312185000) * => (column=strategy_options, value={"datacenter1":"1"}, timestamp=1327061028312185000) * * schema_columnfamilies * --------------------- * RowKey: ks * => (column=cf:bloom_filter_fp_chance, value=0.0, timestamp=1327061105833119000) * => (column=cf:caching, value="NONE", timestamp=1327061105833119000) * => (column=cf:column_type, value="Standard", timestamp=1327061105833119000) * => (column=cf:comment, value="ColumnFamily", timestamp=1327061105833119000) * => (column=cf:default_validation_class, value="org.apache.cassandra.db.marshal.BytesType", timestamp=1327061105833119000) * => (column=cf:gc_grace_seconds, value=864000, timestamp=1327061105833119000) * => (column=cf:id, value=1000, timestamp=1327061105833119000) * => (column=cf:key_alias, value="S0VZ", timestamp=1327061105833119000) * ... part of the output omitted. * * schema_columns * -------------- * RowKey: ks * => (column=cf:c:index_name, value=null, timestamp=1327061105833119000) * => (column=cf:c:index_options, value=null, timestamp=1327061105833119000) * => (column=cf:c:index_type, value=null, timestamp=1327061105833119000) * => (column=cf:c:name, value="aGVsbG8=", timestamp=1327061105833119000) * => (column=cf:c:validation_class, value="org.apache.cassandra.db.marshal.AsciiType", timestamp=1327061105833119000) */ public class DefsTables { private static final Logger logger = LoggerFactory.getLogger(DefsTables.class); /** * Load keyspace definitions for the system keyspace (system.SCHEMA_KEYSPACES_CF) * * @return Collection of found keyspace definitions */ public static Collection<KSMetaData> loadFromKeyspace() { List<Row> serializedSchema = SystemKeyspace.serializedSchema(SystemKeyspace.SCHEMA_KEYSPACES_CF); List<KSMetaData> keyspaces = new ArrayList<KSMetaData>(serializedSchema.size()); for (Row row : serializedSchema) { if (Schema.invalidSchemaRow(row) || Schema.ignoredSchemaRow(row)) continue; keyspaces.add(KSMetaData.fromSchema(row, serializedColumnFamilies(row.key))); } return keyspaces; } public static ByteBuffer searchComposite(String name, boolean start) { assert name != null; ByteBuffer nameBytes = UTF8Type.instance.decompose(name); int length = nameBytes.remaining(); byte[] bytes = new byte[2 + length + 1]; bytes[0] = (byte)((length >> 8) & 0xFF); bytes[1] = (byte)(length & 0xFF); ByteBufferUtil.arrayCopy(nameBytes, 0, bytes, 2, length); bytes[bytes.length - 1] = (byte)(start ? 0 : 1); return ByteBuffer.wrap(bytes); } private static Row serializedColumnFamilies(DecoratedKey ksNameKey) { ColumnFamilyStore cfsStore = SystemKeyspace.schemaCFS(SystemKeyspace.SCHEMA_COLUMNFAMILIES_CF); return new Row(ksNameKey, cfsStore.getColumnFamily(QueryFilter.getIdentityFilter(ksNameKey, SystemKeyspace.SCHEMA_COLUMNFAMILIES_CF, System.currentTimeMillis()))); } /** * Merge remote schema in form of row mutations with local and mutate ks/cf metadata objects * (which also involves fs operations on add/drop ks/cf) * * @param mutations the schema changes to apply * * @throws ConfigurationException If one of metadata attributes has invalid value * @throws IOException If data was corrupted during transportation or failed to apply fs operations */ public static synchronized void mergeSchema(Collection<RowMutation> mutations) throws ConfigurationException, IOException { logger.debug("pgaref - MERGE SCHEMA CALLED"); // current state of the schema Map<DecoratedKey, ColumnFamily> oldKeyspaces = SystemKeyspace.getSchema(SystemKeyspace.SCHEMA_KEYSPACES_CF); Map<DecoratedKey, ColumnFamily> oldColumnFamilies = SystemKeyspace.getSchema(SystemKeyspace.SCHEMA_COLUMNFAMILIES_CF); for (RowMutation mutation : mutations) mutation.apply(); if (!StorageService.instance.isClientMode()) flushSchemaCFs(); // with new data applied Map<DecoratedKey, ColumnFamily> newKeyspaces = SystemKeyspace.getSchema(SystemKeyspace.SCHEMA_KEYSPACES_CF); Map<DecoratedKey, ColumnFamily> newColumnFamilies = SystemKeyspace.getSchema(SystemKeyspace.SCHEMA_COLUMNFAMILIES_CF); Set<String> keyspacesToDrop = mergeKeyspaces(oldKeyspaces, newKeyspaces); mergeColumnFamilies(oldColumnFamilies, newColumnFamilies); // it is safe to drop a keyspace only when all nested ColumnFamilies where deleted for (String keyspaceToDrop : keyspacesToDrop) dropKeyspace(keyspaceToDrop); Schema.instance.updateVersionAndAnnounce(); } private static Set<String> mergeKeyspaces(Map<DecoratedKey, ColumnFamily> old, Map<DecoratedKey, ColumnFamily> updated) { // calculate the difference between old and new states (note that entriesOnlyLeft() will be always empty) MapDifference<DecoratedKey, ColumnFamily> diff = Maps.difference(old, updated); /** * At first step we check if any new keyspaces were added. */ for (Map.Entry<DecoratedKey, ColumnFamily> entry : diff.entriesOnlyOnRight().entrySet()) { ColumnFamily ksAttrs = entry.getValue(); // we don't care about nested ColumnFamilies here because those are going to be processed separately if (!(ksAttrs.getColumnCount() == 0)) addKeyspace(KSMetaData.fromSchema(new Row(entry.getKey(), entry.getValue()), Collections.<CFMetaData>emptyList())); } /** * At second step we check if there were any keyspaces re-created, in this context * re-created means that they were previously deleted but still exist in the low-level schema as empty keys */ Map<DecoratedKey, MapDifference.ValueDifference<ColumnFamily>> modifiedEntries = diff.entriesDiffering(); // instead of looping over all modified entries and skipping processed keys all the time // we would rather store "left to process" items and iterate over them removing already met keys List<DecoratedKey> leftToProcess = new ArrayList<DecoratedKey>(modifiedEntries.size()); for (Map.Entry<DecoratedKey, MapDifference.ValueDifference<ColumnFamily>> entry : modifiedEntries.entrySet()) { ColumnFamily prevValue = entry.getValue().leftValue(); ColumnFamily newValue = entry.getValue().rightValue(); if (prevValue.getColumnCount() == 0) { addKeyspace(KSMetaData.fromSchema(new Row(entry.getKey(), newValue), Collections.<CFMetaData>emptyList())); continue; } leftToProcess.add(entry.getKey()); } if (leftToProcess.size() == 0) return Collections.emptySet(); /** * At final step we updating modified keyspaces and saving keyspaces drop them later */ Set<String> keyspacesToDrop = new HashSet<String>(); for (DecoratedKey key : leftToProcess) { MapDifference.ValueDifference<ColumnFamily> valueDiff = modifiedEntries.get(key); ColumnFamily newState = valueDiff.rightValue(); if (newState.getColumnCount() == 0) keyspacesToDrop.add(AsciiType.instance.getString(key.key)); else updateKeyspace(KSMetaData.fromSchema(new Row(key, newState), Collections.<CFMetaData>emptyList())); } return keyspacesToDrop; } private static void mergeColumnFamilies(Map<DecoratedKey, ColumnFamily> old, Map<DecoratedKey, ColumnFamily> updated) { // calculate the difference between old and new states (note that entriesOnlyLeft() will be always empty) MapDifference<DecoratedKey, ColumnFamily> diff = Maps.difference(old, updated); // check if any new Keyspaces with ColumnFamilies were added. for (Map.Entry<DecoratedKey, ColumnFamily> entry : diff.entriesOnlyOnRight().entrySet()) { ColumnFamily cfAttrs = entry.getValue(); if (!(cfAttrs.getColumnCount() == 0)) { Map<String, CFMetaData> cfDefs = KSMetaData.deserializeColumnFamilies(new Row(entry.getKey(), cfAttrs)); for (CFMetaData cfDef : cfDefs.values()) addColumnFamily(cfDef); } } // deal with modified ColumnFamilies (remember that all of the keyspace nested ColumnFamilies are put to the single row) Map<DecoratedKey, MapDifference.ValueDifference<ColumnFamily>> modifiedEntries = diff.entriesDiffering(); for (DecoratedKey keyspace : modifiedEntries.keySet()) { MapDifference.ValueDifference<ColumnFamily> valueDiff = modifiedEntries.get(keyspace); ColumnFamily prevValue = valueDiff.leftValue(); // state before external modification ColumnFamily newValue = valueDiff.rightValue(); // updated state Row newRow = new Row(keyspace, newValue); if (prevValue.getColumnCount() == 0) // whole keyspace was deleted and now it's re-created { for (CFMetaData cfm : KSMetaData.deserializeColumnFamilies(newRow).values()) addColumnFamily(cfm); } else if (newValue.getColumnCount() == 0) // whole keyspace is deleted { for (CFMetaData cfm : KSMetaData.deserializeColumnFamilies(new Row(keyspace, prevValue)).values()) dropColumnFamily(cfm.ksName, cfm.cfName); } else // has modifications in the nested ColumnFamilies, need to perform nested diff to determine what was really changed { String ksName = AsciiType.instance.getString(keyspace.key); Map<String, CFMetaData> oldCfDefs = new HashMap<String, CFMetaData>(); for (CFMetaData cfm : Schema.instance.getKSMetaData(ksName).cfMetaData().values()) oldCfDefs.put(cfm.cfName, cfm); Map<String, CFMetaData> newCfDefs = KSMetaData.deserializeColumnFamilies(newRow); MapDifference<String, CFMetaData> cfDefDiff = Maps.difference(oldCfDefs, newCfDefs); for (CFMetaData cfDef : cfDefDiff.entriesOnlyOnRight().values()) addColumnFamily(cfDef); for (CFMetaData cfDef : cfDefDiff.entriesOnlyOnLeft().values()) dropColumnFamily(cfDef.ksName, cfDef.cfName); for (MapDifference.ValueDifference<CFMetaData> cfDef : cfDefDiff.entriesDiffering().values()) updateColumnFamily(cfDef.rightValue()); } } } private static void addKeyspace(KSMetaData ksm) { assert Schema.instance.getKSMetaData(ksm.name) == null; Schema.instance.load(ksm); if (!StorageService.instance.isClientMode()) { Keyspace.open(ksm.name); MigrationManager.instance.notifyCreateKeyspace(ksm); } } private static void addColumnFamily(CFMetaData cfm) { assert Schema.instance.getCFMetaData(cfm.ksName, cfm.cfName) == null; KSMetaData ksm = Schema.instance.getKSMetaData(cfm.ksName); ksm = KSMetaData.cloneWith(ksm, Iterables.concat(ksm.cfMetaData().values(), Collections.singleton(cfm))); logger.info("Loading {}", cfm); Schema.instance.load(cfm); // make sure it's init-ed w/ the old definitions first, // since we're going to call initCf on the new one manually Keyspace.open(cfm.ksName); Schema.instance.setKeyspaceDefinition(ksm); if (!StorageService.instance.isClientMode()) { Keyspace.open(ksm.name).initCf(cfm.cfId, cfm.cfName, true); MigrationManager.instance.notifyCreateColumnFamily(cfm); } } private static void updateKeyspace(KSMetaData newState) { KSMetaData oldKsm = Schema.instance.getKSMetaData(newState.name); assert oldKsm != null; KSMetaData newKsm = KSMetaData.cloneWith(oldKsm.reloadAttributes(), oldKsm.cfMetaData().values()); Schema.instance.setKeyspaceDefinition(newKsm); if (!StorageService.instance.isClientMode()) { Keyspace.open(newState.name).createReplicationStrategy(newKsm); MigrationManager.instance.notifyUpdateKeyspace(newKsm); } } private static void updateColumnFamily(CFMetaData newState) { CFMetaData cfm = Schema.instance.getCFMetaData(newState.ksName, newState.cfName); assert cfm != null; cfm.reload(); if (!StorageService.instance.isClientMode()) { Keyspace keyspace = Keyspace.open(cfm.ksName); keyspace.getColumnFamilyStore(cfm.cfName).reload(); MigrationManager.instance.notifyUpdateColumnFamily(cfm); } } private static void dropKeyspace(String ksName) { KSMetaData ksm = Schema.instance.getKSMetaData(ksName); String snapshotName = Keyspace.getTimestampedSnapshotName(ksName); CompactionManager.instance.interruptCompactionFor(ksm.cfMetaData().values(), true); // remove all cfs from the keyspace instance. for (CFMetaData cfm : ksm.cfMetaData().values()) { ColumnFamilyStore cfs = Keyspace.open(ksm.name).getColumnFamilyStore(cfm.cfName); Schema.instance.purge(cfm); if (!StorageService.instance.isClientMode()) { if (DatabaseDescriptor.isAutoSnapshot()) cfs.snapshot(snapshotName); Keyspace.open(ksm.name).dropCf(cfm.cfId); } } // remove the keyspace from the static instances. Keyspace.clear(ksm.name); Schema.instance.clearKeyspaceDefinition(ksm); if (!StorageService.instance.isClientMode()) { MigrationManager.instance.notifyDropKeyspace(ksm); } } private static void dropColumnFamily(String ksName, String cfName) { KSMetaData ksm = Schema.instance.getKSMetaData(ksName); assert ksm != null; ColumnFamilyStore cfs = Keyspace.open(ksName).getColumnFamilyStore(cfName); assert cfs != null; // reinitialize the keyspace. CFMetaData cfm = ksm.cfMetaData().get(cfName); Schema.instance.purge(cfm); Schema.instance.setKeyspaceDefinition(makeNewKeyspaceDefinition(ksm, cfm)); CompactionManager.instance.interruptCompactionFor(Arrays.asList(cfm), true); if (!StorageService.instance.isClientMode()) { if (DatabaseDescriptor.isAutoSnapshot()) cfs.snapshot(Keyspace.getTimestampedSnapshotName(cfs.name)); Keyspace.open(ksm.name).dropCf(cfm.cfId); MigrationManager.instance.notifyDropColumnFamily(cfm); } } private static KSMetaData makeNewKeyspaceDefinition(KSMetaData ksm, CFMetaData toExclude) { // clone ksm but do not include the new def List<CFMetaData> newCfs = new ArrayList<CFMetaData>(ksm.cfMetaData().values()); newCfs.remove(toExclude); assert newCfs.size() == ksm.cfMetaData().size() - 1; return KSMetaData.cloneWith(ksm, newCfs); } private static void flushSchemaCFs() { SystemKeyspace.forceBlockingFlush(SystemKeyspace.SCHEMA_KEYSPACES_CF); SystemKeyspace.forceBlockingFlush(SystemKeyspace.SCHEMA_COLUMNFAMILIES_CF); SystemKeyspace.forceBlockingFlush(SystemKeyspace.SCHEMA_COLUMNS_CF); SystemKeyspace.forceBlockingFlush(SystemKeyspace.SCHEMA_TRIGGERS_CF); } }