com.datastax.driver.core.TableMetadata Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of cassandra-driver-core Show documentation
Show all versions of cassandra-driver-core Show documentation
A driver for Apache Cassandra 1.2+ that works exclusively with the Cassandra Query Language version 3
(CQL3) and Cassandra's binary protocol.
/*
* Copyright (C) 2012-2015 DataStax Inc.
*
* Licensed 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 com.datastax.driver.core;
import com.datastax.driver.core.utils.MoreObjects;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
/**
* Describes a Table.
*/
public class TableMetadata extends AbstractTableMetadata {
private static final Logger logger = LoggerFactory.getLogger(TableMetadata.class);
private static final String CF_ID_V2 = "cf_id";
private static final String CF_ID_V3 = "id";
private static final String KEY_VALIDATOR = "key_validator";
private static final String COMPARATOR = "comparator";
private static final String VALIDATOR = "default_validator";
private static final String KEY_ALIASES = "key_aliases";
private static final String COLUMN_ALIASES = "column_aliases";
private static final String VALUE_ALIAS = "value_alias";
private static final String DEFAULT_KEY_ALIAS = "key";
private static final String DEFAULT_COLUMN_ALIAS = "column";
private static final String DEFAULT_VALUE_ALIAS = "value";
private static final String FLAGS = "flags";
private static final String DENSE = "dense";
private static final String SUPER = "super";
private static final String COMPOUND = "compound";
private static final String EMPTY_TYPE = "empty";
private final Map indexes;
private final Map views;
private TableMetadata(KeyspaceMetadata keyspace,
String name,
UUID id,
List partitionKey,
List clusteringColumns,
Map columns,
Map indexes,
TableOptionsMetadata options,
List clusteringOrder,
VersionNumber cassandraVersion) {
super(keyspace, name, id, partitionKey, clusteringColumns, columns, options, clusteringOrder, cassandraVersion);
this.indexes = indexes;
this.views = new HashMap();
}
static TableMetadata build(KeyspaceMetadata ksm, Row row, Map rawCols, List indexRows, String nameColumn, VersionNumber cassandraVersion, Cluster cluster) {
String name = row.getString(nameColumn);
UUID id = null;
if (cassandraVersion.getMajor() == 2 && cassandraVersion.getMinor() >= 1)
id = row.getUUID(CF_ID_V2);
else if (cassandraVersion.getMajor() > 2)
id = row.getUUID(CF_ID_V3);
DataTypeClassNameParser.ParseResult comparator = null;
DataTypeClassNameParser.ParseResult keyValidator = null;
List columnAliases = null;
ProtocolVersion protocolVersion = cluster.getConfiguration().getProtocolOptions().getProtocolVersion();
CodecRegistry codecRegistry = cluster.getConfiguration().getCodecRegistry();
if (cassandraVersion.getMajor() <= 2) {
comparator = DataTypeClassNameParser.parseWithComposite(row.getString(COMPARATOR), protocolVersion, codecRegistry);
keyValidator = DataTypeClassNameParser.parseWithComposite(row.getString(KEY_VALIDATOR), protocolVersion, codecRegistry);
columnAliases = cassandraVersion.getMajor() >= 2 || row.getString(COLUMN_ALIASES) == null
? Collections.emptyList()
: SimpleJSONParser.parseStringList(row.getString(COLUMN_ALIASES));
}
int partitionKeySize = findPartitionKeySize(rawCols.values(), keyValidator);
int clusteringSize;
boolean isDense;
boolean isCompact;
if (cassandraVersion.getMajor() > 2) {
Set flags = row.getSet(FLAGS, String.class);
isDense = flags.contains(DENSE);
boolean isSuper = flags.contains(SUPER);
boolean isCompound = flags.contains(COMPOUND);
isCompact = isSuper || isDense || !isCompound;
boolean isStaticCompact = !isSuper && !isDense && !isCompound;
if (isStaticCompact) {
rawCols = pruneStaticCompactTableColumns(rawCols);
}
if (isDense) {
rawCols = pruneDenseTableColumnsV3(rawCols);
}
clusteringSize = findClusteringSize(comparator, rawCols.values(), columnAliases, cassandraVersion);
} else {
assert comparator != null;
clusteringSize = findClusteringSize(comparator, rawCols.values(), columnAliases, cassandraVersion);
isDense = clusteringSize != comparator.types.size() - 1;
if (isDense) {
rawCols = pruneDenseTableColumnsV2(rawCols);
}
isCompact = isDense || !comparator.isComposite;
}
List partitionKey = new ArrayList(Collections.nCopies(partitionKeySize, null));
List clusteringColumns = new ArrayList(Collections.nCopies(clusteringSize, null));
List clusteringOrder = new ArrayList(Collections.nCopies(clusteringSize, null));
// We use a linked hashmap because we will keep this in the order of a 'SELECT * FROM ...'.
LinkedHashMap columns = new LinkedHashMap();
LinkedHashMap indexes = new LinkedHashMap();
TableOptionsMetadata options = null;
try {
options = new TableOptionsMetadata(row, isCompact, cassandraVersion);
} catch (RuntimeException e) {
// See ControlConnection#refreshSchema for why we'd rather not probably this further. Since table options is one thing
// that tends to change often in Cassandra, it's worth special casing this.
logger.error(String.format("Error parsing schema options for table %s.%s: "
+ "Cluster.getMetadata().getKeyspace(\"%s\").getTable(\"%s\").getOptions() will return null",
ksm.getName(), name, ksm.getName(), name), e);
}
TableMetadata tm = new TableMetadata(ksm, name, id, partitionKey, clusteringColumns, columns, indexes, options, clusteringOrder, cassandraVersion);
// We use this temporary set just so non PK columns are added in lexicographical order, which is the one of a
// 'SELECT * FROM ...'
Set otherColumns = new TreeSet(columnMetadataComparator);
if (cassandraVersion.getMajor() < 2) {
assert comparator != null;
assert keyValidator != null;
assert columnAliases != null;
// In C* 1.2, only the REGULAR columns are in the columns schema table, so we need to add the names from
// the aliases (and make sure we handle default aliases).
List keyAliases = row.getString(KEY_ALIASES) == null
? Collections.emptyList()
: SimpleJSONParser.parseStringList(row.getString(KEY_ALIASES));
for (int i = 0; i < partitionKey.size(); i++) {
String alias = keyAliases.size() > i ? keyAliases.get(i) : (i == 0 ? DEFAULT_KEY_ALIAS : DEFAULT_KEY_ALIAS + (i + 1));
partitionKey.set(i, ColumnMetadata.forAlias(tm, alias, keyValidator.types.get(i)));
}
for (int i = 0; i < clusteringSize; i++) {
String alias = columnAliases.size() > i ? columnAliases.get(i) : DEFAULT_COLUMN_ALIAS + (i + 1);
clusteringColumns.set(i, ColumnMetadata.forAlias(tm, alias, comparator.types.get(i)));
clusteringOrder.set(i, comparator.reversed.get(i) ? ClusteringOrder.DESC : ClusteringOrder.ASC);
}
// if we're dense, chances are that we have a single regular "value" column with an alias
if (isDense) {
String alias = row.isNull(VALUE_ALIAS) ? DEFAULT_VALUE_ALIAS : row.getString(VALUE_ALIAS);
// ...unless the table does not have any regular column, only primary key columns (JAVA-873)
if (!alias.isEmpty()) {
DataType type = DataTypeClassNameParser.parseOne(row.getString(VALIDATOR), protocolVersion, codecRegistry);
otherColumns.add(ColumnMetadata.forAlias(tm, alias, type));
}
}
}
for (ColumnMetadata.Raw rawCol : rawCols.values()) {
DataType dataType;
if (cassandraVersion.getMajor() >= 3) {
dataType = DataTypeCqlNameParser.parse(rawCol.dataType, cluster, ksm.getName(), ksm.userTypes, null, false, false);
} else {
dataType = DataTypeClassNameParser.parseOne(rawCol.dataType, protocolVersion, codecRegistry);
}
ColumnMetadata col = ColumnMetadata.fromRaw(tm, rawCol, dataType);
switch (rawCol.kind) {
case PARTITION_KEY:
partitionKey.set(rawCol.position, col);
break;
case CLUSTERING_COLUMN:
clusteringColumns.set(rawCol.position, col);
clusteringOrder.set(rawCol.position, rawCol.isReversed ? ClusteringOrder.DESC : ClusteringOrder.ASC);
break;
default:
otherColumns.add(col);
break;
}
// legacy secondary indexes (C* < 3.0)
IndexMetadata index = IndexMetadata.fromLegacy(col, rawCol);
if (index != null)
indexes.put(index.getName(), index);
}
for (ColumnMetadata c : partitionKey)
columns.put(c.getName(), c);
for (ColumnMetadata c : clusteringColumns)
columns.put(c.getName(), c);
for (ColumnMetadata c : otherColumns)
columns.put(c.getName(), c);
// create secondary indexes (C* >= 3.0)
if (indexRows != null)
for (Row indexRow : indexRows) {
IndexMetadata index = IndexMetadata.fromRow(tm, indexRow);
indexes.put(index.getName(), index);
}
return tm;
}
/**
* Upon migration from thrift to CQL, we internally create a pair of surrogate clustering/regular columns
* for compact static tables. These columns shouldn't be exposed to the user but are currently returned by C*.
* We also need to remove the static keyword for all other columns in the table.
*/
private static Map pruneStaticCompactTableColumns(Map rawCols) {
Collection cols = rawCols.values();
Iterator it = cols.iterator();
while (it.hasNext()) {
ColumnMetadata.Raw col = it.next();
if (col.kind == ColumnMetadata.Raw.Kind.CLUSTERING_COLUMN) {
// remove "column1 text" clustering column
it.remove();
} else if (col.kind == ColumnMetadata.Raw.Kind.REGULAR) {
// remove "value blob" regular column
it.remove();
} else if (col.kind == ColumnMetadata.Raw.Kind.STATIC) {
// remove "static" keyword
col.kind = ColumnMetadata.Raw.Kind.REGULAR;
}
}
return rawCols;
}
/**
* Upon migration from thrift to CQL, we internally create a surrogate column "value" of type
* EmptyType for dense tables. This column shouldn't be exposed to the user but is currently returned by C*.
*/
private static Map pruneDenseTableColumnsV3(Map rawCols) {
Collection cols = rawCols.values();
Iterator it = cols.iterator();
while (it.hasNext()) {
ColumnMetadata.Raw col = it.next();
if (col.kind == ColumnMetadata.Raw.Kind.REGULAR
&& col.dataType.equals(EMPTY_TYPE)) {
// remove "value empty" regular column
it.remove();
}
}
return rawCols;
}
private static Map pruneDenseTableColumnsV2(Map rawCols) {
Collection cols = rawCols.values();
Iterator it = cols.iterator();
while (it.hasNext()) {
ColumnMetadata.Raw col = it.next();
if (col.kind == ColumnMetadata.Raw.Kind.COMPACT_VALUE && col.name.isEmpty()) {
// remove "" blob regular COMPACT_VALUE column
it.remove();
}
}
return rawCols;
}
private static int findPartitionKeySize(Collection cols, DataTypeClassNameParser.ParseResult keyValidator) {
// C* 1.2, 2.0, 2.1 and 2.2
if (keyValidator != null)
return keyValidator.types.size();
// C* 3.0 onwards
int maxId = -1;
for (ColumnMetadata.Raw col : cols)
if (col.kind == ColumnMetadata.Raw.Kind.PARTITION_KEY)
maxId = Math.max(maxId, col.position);
return maxId + 1;
}
private static int findClusteringSize(DataTypeClassNameParser.ParseResult comparator,
Collection cols,
List columnAliases,
VersionNumber cassandraVersion) {
// In 2.0 onwards, this is relatively easy, we just find the biggest 'position' amongst the clustering columns.
// For 1.2 however, this is slightly more subtle: we need to infer it based on whether the comparator is composite or not, and whether we have
// regular columns or not.
if (cassandraVersion.getMajor() >= 2) {
int maxId = -1;
for (ColumnMetadata.Raw col : cols)
if (col.kind == ColumnMetadata.Raw.Kind.CLUSTERING_COLUMN)
maxId = Math.max(maxId, col.position);
return maxId + 1;
} else {
int size = comparator.types.size();
if (comparator.isComposite)
return !comparator.collections.isEmpty() || (columnAliases.size() == size - 1 && comparator.types.get(size - 1).equals(DataType.text())) ? size - 1 : size;
else
// We know cols only has the REGULAR ones for 1.2
return !columnAliases.isEmpty() || cols.isEmpty() ? size : 0;
}
}
/**
* Returns metadata on a index of this table.
*
* @param name the name of the index to retrieve ({@code name} will be
* interpreted as a case-insensitive identifier unless enclosed in double-quotes,
* see {@link Metadata#quote}).
* @return the metadata for the {@code name} index if it exists, or
* {@code null} otherwise.
*/
public IndexMetadata getIndex(String name) {
return indexes.get(Metadata.handleId(name));
}
/**
* Returns all indexes based on this table.
*
* @return all indexes based on this table.
*/
public Collection getIndexes() {
return Collections.unmodifiableCollection(indexes.values());
}
/**
* Returns metadata on a view of this table.
*
* @param name the name of the view to retrieve ({@code name} will be
* interpreted as a case-insensitive identifier unless enclosed in double-quotes,
* see {@link Metadata#quote}).
* @return the metadata for the {@code name} view if it exists, or
* {@code null} otherwise.
*/
public MaterializedViewMetadata getView(String name) {
return views.get(Metadata.handleId(name));
}
/**
* Returns all views based on this table.
*
* @return all views based on this table.
*/
public Collection getViews() {
return Collections.unmodifiableCollection(views.values());
}
void add(MaterializedViewMetadata view) {
views.put(view.getName(), view);
}
/**
* Returns a {@code String} containing CQL queries representing this
* table and the index on it.
*
* In other words, this method returns the queries that would allow you to
* recreate the schema of this table, along with the indexes and views defined on
* this table, if any.
*
* Note that the returned String is formatted to be human readable (for
* some definition of human readable at least).
*
* @return the CQL queries representing this table schema as a {code
* String}.
*/
@Override
public String exportAsString() {
StringBuilder sb = new StringBuilder();
sb.append(super.exportAsString());
for (IndexMetadata index : indexes.values()) {
sb.append('\n').append(index.asCQLQuery());
}
for (MaterializedViewMetadata view : views.values()) {
sb.append('\n').append(view.asCQLQuery());
}
return sb.toString();
}
@Override
protected String asCQLQuery(boolean formatted) {
StringBuilder sb = new StringBuilder();
sb.append("CREATE TABLE ").append(Metadata.quoteIfNecessary(keyspace.getName())).append('.').append(Metadata.quoteIfNecessary(name)).append(" (");
newLine(sb, formatted);
for (ColumnMetadata cm : columns.values())
newLine(sb.append(spaces(4, formatted)).append(cm).append(',').append(spaces(1, !formatted)), formatted);
// PK
sb.append(spaces(4, formatted)).append("PRIMARY KEY (");
if (partitionKey.size() == 1) {
sb.append(Metadata.quoteIfNecessary(partitionKey.get(0).getName()));
} else {
sb.append('(');
boolean first = true;
for (ColumnMetadata cm : partitionKey) {
if (first)
first = false;
else
sb.append(", ");
sb.append(Metadata.quoteIfNecessary(cm.getName()));
}
sb.append(')');
}
for (ColumnMetadata cm : clusteringColumns)
sb.append(", ").append(Metadata.quoteIfNecessary(cm.getName()));
sb.append(')');
newLine(sb, formatted);
// end PK
sb.append(")");
appendOptions(sb, formatted);
return sb.toString();
}
@Override
public boolean equals(Object other) {
if (other == this)
return true;
if (!(other instanceof TableMetadata))
return false;
TableMetadata that = (TableMetadata) other;
return MoreObjects.equal(this.name, that.name) &&
MoreObjects.equal(this.id, that.id) &&
MoreObjects.equal(this.partitionKey, that.partitionKey) &&
MoreObjects.equal(this.clusteringColumns, that.clusteringColumns) &&
MoreObjects.equal(this.columns, that.columns) &&
MoreObjects.equal(this.options, that.options) &&
MoreObjects.equal(this.clusteringOrder, that.clusteringOrder) &&
MoreObjects.equal(this.indexes, that.indexes) &&
MoreObjects.equal(this.views, that.views);
}
@Override
public int hashCode() {
return MoreObjects.hashCode(name, id, partitionKey, clusteringColumns, columns, options, clusteringOrder, indexes, views);
}
}