/*
* 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.hadoop.pig;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.charset.CharacterCodingException;
import java.util.*;
import org.apache.cassandra.db.IColumn;
import org.apache.cassandra.db.Column;
import org.apache.cassandra.db.marshal.*;
import org.apache.cassandra.exceptions.ConfigurationException;
import org.apache.cassandra.hadoop.*;
import org.apache.cassandra.hadoop.cql3.CqlConfigHelper;
import org.apache.cassandra.thrift.*;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.hadoop.mapreduce.*;
import org.apache.pig.Expression;
import org.apache.pig.Expression.OpType;
import org.apache.pig.ResourceSchema;
import org.apache.pig.ResourceSchema.ResourceFieldSchema;
import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit;
import org.apache.pig.data.*;
import org.apache.pig.impl.util.UDFContext;
import org.apache.thrift.TException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A LoadStoreFunc for retrieving data from and storing data to Cassandra
*
* A row from a standard CF will be returned as nested tuples:
* (((key1, value1), (key2, value2)), ((name1, val1), (name2, val2))).
*/
public class CqlStorage extends AbstractCassandraStorage
{
private static final Logger logger = LoggerFactory.getLogger(CqlStorage.class);
private RecordReader<Map<String, ByteBuffer>, Map<String, ByteBuffer>> reader;
private RecordWriter<Map<String, ByteBuffer>, List<ByteBuffer>> writer;
private int pageSize = 1000;
private String columns;
private String outputQuery;
private String whereClause;
public CqlStorage()
{
this(1000);
}
/** @param limit number of CQL rows to fetch in a thrift request */
public CqlStorage(int pageSize)
{
super();
this.pageSize = pageSize;
DEFAULT_INPUT_FORMAT = "org.apache.cassandra.hadoop.cql3.CqlPagingInputFormat";
DEFAULT_OUTPUT_FORMAT = "org.apache.cassandra.hadoop.cql3.CqlOutputFormat";
}
public void prepareToRead(RecordReader reader, PigSplit split)
{
this.reader = reader;
}
/** get next row */
public Tuple getNext() throws IOException
{
try
{
// load the next pair
if (!reader.nextKeyValue())
return null;
CfDef cfDef = getCfDef(loadSignature);
Map<String, ByteBuffer> keys = reader.getCurrentKey();
Map<String, ByteBuffer> columns = reader.getCurrentValue();
assert keys != null && columns != null;
// add key columns to the map
for (Map.Entry<String,ByteBuffer> key : keys.entrySet())
columns.put(key.getKey(), key.getValue());
Tuple tuple = TupleFactory.getInstance().newTuple(cfDef.column_metadata.size());
Iterator<ColumnDef> itera = cfDef.column_metadata.iterator();
int i = 0;
while (itera.hasNext())
{
ColumnDef cdef = itera.next();
ByteBuffer columnValue = columns.get(ByteBufferUtil.string(cdef.name.duplicate()));
if (columnValue != null)
{
IColumn column = new Column(cdef.name, columnValue);
AbstractType<?> validator = getValidatorMap(cfDef).get(column.name());
setTupleValue(tuple, i, cqlColumnToObj(column, cfDef), validator);
}
else
tuple.set(i, null);
i++;
}
return tuple;
}
catch (InterruptedException e)
{
throw new IOException(e.getMessage());
}
}
/** set the value to the position of the tuple */
private void setTupleValue(Tuple tuple, int position, Object value, AbstractType<?> validator) throws ExecException
{
if (validator instanceof CollectionType)
setCollectionTupleValues(tuple, position, value, validator);
else
setTupleValue(tuple, position, value);
}
/** set the values of set/list at and after the position of the tuple */
private void setCollectionTupleValues(Tuple tuple, int position, Object value, AbstractType<?> validator) throws ExecException
{
if (validator instanceof MapType)
{
setMapTupleValues(tuple, position, value, validator);
return;
}
AbstractType<?> elementValidator;
if (validator instanceof SetType)
elementValidator = ((SetType<?>) validator).elements;
else if (validator instanceof ListType)
elementValidator = ((ListType<?>) validator).elements;
else
return;
int i = 0;
Tuple innerTuple = TupleFactory.getInstance().newTuple(((Collection<?>) value).size());
for (Object entry : (Collection<?>) value)
{
setTupleValue(innerTuple, i, entry, elementValidator);
i++;
}
tuple.set(position, innerTuple);
}
/** set the values of set/list at and after the position of the tuple */
private void setMapTupleValues(Tuple tuple, int position, Object value, AbstractType<?> validator) throws ExecException
{
AbstractType<?> keyValidator = ((MapType<?, ?>) validator).keys;
AbstractType<?> valueValidator = ((MapType<?, ?>) validator).values;
int i = 0;
Tuple innerTuple = TupleFactory.getInstance().newTuple(((Map<?,?>) value).size());
for(Map.Entry<?,?> entry : ((Map<Object, Object>)value).entrySet())
{
Tuple mapEntryTuple = TupleFactory.getInstance().newTuple(2);
setTupleValue(mapEntryTuple, 0, entry.getKey(), keyValidator);
setTupleValue(mapEntryTuple, 1, entry.getValue(), valueValidator);
innerTuple.set(i, mapEntryTuple);
i++;
}
tuple.set(position, innerTuple);
}
/** convert a cql column to an object */
private Object cqlColumnToObj(IColumn col, CfDef cfDef) throws IOException
{
// standard
Map<ByteBuffer,AbstractType> validators = getValidatorMap(cfDef);
if (validators.get(col.name()) == null)
{
Map<MarshallerType, AbstractType> marshallers = getDefaultMarshallers(cfDef);
return marshallers.get(MarshallerType.DEFAULT_VALIDATOR).compose(col.value());
}
else
return validators.get(col.name()).compose(col.value());
}
/** set read configuration settings */
public void setLocation(String location, Job job) throws IOException
{
conf = job.getConfiguration();
setLocationFromUri(location);
if (username != null && password != null)
ConfigHelper.setInputKeyspaceUserNameAndPassword(conf, username, password);
if (splitSize > 0)
ConfigHelper.setInputSplitSize(conf, splitSize);
if (partitionerClass!= null)
ConfigHelper.setInputPartitioner(conf, partitionerClass);
ConfigHelper.setInputColumnFamily(conf, keyspace, column_family);
setConnectionInformation();
CqlConfigHelper.setInputCQLPageRowSize(conf, String.valueOf(pageSize));
if (columns != null && !columns.trim().isEmpty())
CqlConfigHelper.setInputColumns(conf, columns);
String whereClauseForPartitionFilter = getWhereClauseForPartitionFilter();
String wc = whereClause != null && !whereClause.trim().isEmpty()
? whereClauseForPartitionFilter == null ? whereClause: String.format("%s AND %s", whereClause.trim(), whereClauseForPartitionFilter)
: whereClauseForPartitionFilter;
if (wc != null)
{
logger.debug("where clause: {}", wc);
CqlConfigHelper.setInputWhereClauses(conf, wc);
}
if (System.getenv(PIG_INPUT_SPLIT_SIZE) != null)
{
try
{
ConfigHelper.setInputSplitSize(conf, Integer.valueOf(System.getenv(PIG_INPUT_SPLIT_SIZE)));
}
catch (NumberFormatException e)
{
throw new RuntimeException("PIG_INPUT_SPLIT_SIZE is not a number", e);
}
}
if (ConfigHelper.getInputRpcPort(conf) == 0)
throw new IOException("PIG_INPUT_RPC_PORT or PIG_RPC_PORT environment variable not set");
if (ConfigHelper.getInputInitialAddress(conf) == null)
throw new IOException("PIG_INPUT_INITIAL_ADDRESS or PIG_INITIAL_ADDRESS environment variable not set");
if (ConfigHelper.getInputPartitioner(conf) == null)
throw new IOException("PIG_INPUT_PARTITIONER or PIG_PARTITIONER environment variable not set");
if (loadSignature == null)
loadSignature = location;
initSchema(loadSignature);
}
/** set store configuration settings */
public void setStoreLocation(String location, Job job) throws IOException
{
conf = job.getConfiguration();
setLocationFromUri(location);
if (username != null && password != null)
ConfigHelper.setOutputKeyspaceUserNameAndPassword(conf, username, password);
if (splitSize > 0)
ConfigHelper.setInputSplitSize(conf, splitSize);
if (partitionerClass!= null)
ConfigHelper.setOutputPartitioner(conf, partitionerClass);
ConfigHelper.setOutputColumnFamily(conf, keyspace, column_family);
CqlConfigHelper.setOutputCql(conf, outputQuery);
setConnectionInformation();
if (ConfigHelper.getOutputRpcPort(conf) == 0)
throw new IOException("PIG_OUTPUT_RPC_PORT or PIG_RPC_PORT environment variable not set");
if (ConfigHelper.getOutputInitialAddress(conf) == null)
throw new IOException("PIG_OUTPUT_INITIAL_ADDRESS or PIG_INITIAL_ADDRESS environment variable not set");
if (ConfigHelper.getOutputPartitioner(conf) == null)
throw new IOException("PIG_OUTPUT_PARTITIONER or PIG_PARTITIONER environment variable not set");
initSchema(storeSignature);
}
/** schema: (value, value, value) where keys are in the front. */
public ResourceSchema getSchema(String location, Job job) throws IOException
{
setLocation(location, job);
CfDef cfDef = getCfDef(loadSignature);
// top-level schema, no type
ResourceSchema schema = new ResourceSchema();
// get default marshallers and validators
Map<MarshallerType, AbstractType> marshallers = getDefaultMarshallers(cfDef);
Map<ByteBuffer, AbstractType> validators = getValidatorMap(cfDef);
// will contain all fields for this schema
List<ResourceFieldSchema> allSchemaFields = new ArrayList<ResourceFieldSchema>();
for (ColumnDef cdef : cfDef.column_metadata)
{
ResourceFieldSchema valSchema = new ResourceFieldSchema();
AbstractType validator = validators.get(cdef.name);
if (validator == null)
validator = marshallers.get(MarshallerType.DEFAULT_VALIDATOR);
valSchema.setName(new String(cdef.getName()));
valSchema.setType(getPigType(validator));
allSchemaFields.add(valSchema);
}
// top level schema contains everything
schema.setFields(allSchemaFields.toArray(new ResourceFieldSchema[allSchemaFields.size()]));
return schema;
}
public void setPartitionFilter(Expression partitionFilter)
{
UDFContext context = UDFContext.getUDFContext();
Properties property = context.getUDFProperties(AbstractCassandraStorage.class);
property.setProperty(PARTITION_FILTER_SIGNATURE, partitionFilterToWhereClauseString(partitionFilter));
}
/** retrieve where clause for partition filter */
private String getWhereClauseForPartitionFilter()
{
UDFContext context = UDFContext.getUDFContext();
Properties property = context.getUDFProperties(AbstractCassandraStorage.class);
return property.getProperty(PARTITION_FILTER_SIGNATURE);
}
public void prepareToWrite(RecordWriter writer)
{
this.writer = writer;
}
/** output: (((name, value), (name, value)), (value ... value), (value...value)) */
public void putNext(Tuple t) throws IOException
{
if (t.size() < 1)
{
// simply nothing here, we can't even delete without a key
logger.warn("Empty output skipped, filter empty tuples to suppress this warning");
return;
}
if (t.getType(0) == DataType.TUPLE)
{
Map<String, ByteBuffer> key = tupleToKeyMap((Tuple)t.get(0));
if (t.getType(1) == DataType.TUPLE)
cqlQueryFromTuple(key, t, 1);
else
throw new IOException("Second argument in output must be a tuple");
}
else
throw new IOException("First argument in output must be a tuple");
}
/** convert key tuple to key map */
private Map<String, ByteBuffer> tupleToKeyMap(Tuple t) throws IOException
{
Map<String, ByteBuffer> keys = new HashMap<String, ByteBuffer>();
for (int i = 0; i < t.size(); i++)
{
if (t.getType(i) == DataType.TUPLE)
{
Tuple inner = (Tuple) t.get(i);
if (inner.size() == 2)
{
Object name = inner.get(0);
if (name != null)
{
keys.put(name.toString(), objToBB(inner.get(1)));
}
else
throw new IOException("Key name was empty");
}
else
throw new IOException("Keys were not in name and value pairs");
}
else
{
throw new IOException("keys was not a tuple");
}
}
return keys;
}
/** send CQL query request using data from tuple */
private void cqlQueryFromTuple(Map<String, ByteBuffer> key, Tuple t, int offset) throws IOException
{
for (int i = offset; i < t.size(); i++)
{
if (t.getType(i) == DataType.TUPLE)
{
Tuple inner = (Tuple) t.get(i);
if (inner.size() > 0)
{
List<ByteBuffer> bindedVariables = bindedVariablesFromTuple(inner);
if (bindedVariables.size() > 0)
sendCqlQuery(key, bindedVariables);
else
throw new IOException("Missing binded variables");
}
}
else
{
throw new IOException("Output type was not a tuple");
}
}
}
/** compose a list of binded variables */
private List<ByteBuffer> bindedVariablesFromTuple(Tuple t) throws IOException
{
List<ByteBuffer> variables = new ArrayList<ByteBuffer>();
for (int i = 0; i < t.size(); i++)
variables.add(objToBB(t.get(i)));
return variables;
}
/** writer write the data by executing CQL query */
private void sendCqlQuery(Map<String, ByteBuffer> key, List<ByteBuffer> bindedVariables) throws IOException
{
try
{
writer.write(key, bindedVariables);
}
catch (InterruptedException e)
{
throw new IOException(e);
}
}
/** include key columns */
protected List<ColumnDef> getColumnMetadata(Cassandra.Client client, boolean cql3Table)
throws InvalidRequestException,
UnavailableException,
TimedOutException,
SchemaDisagreementException,
TException,
CharacterCodingException,
org.apache.cassandra.exceptions.InvalidRequestException,
ConfigurationException,
NotFoundException
{
List<ColumnDef> keyColumns = null;
// get key columns
try
{
keyColumns = getKeysMeta(client);
}
catch(Exception e)
{
logger.error("Error in retrieving key columns" , e);
}
// get other columns
List<ColumnDef> columns = getColumnMeta(client, false);
// combine all columns in a list
if (keyColumns != null && columns != null)
keyColumns.addAll(columns);
return keyColumns;
}
/** cql://[username:password@]<keyspace>/<columnfamily>[?[page_size=<size>]
* [&columns=<col1,col2>][&output_query=<prepared_statement_query>][&where_clause=<clause>]
* [&split_size=<size>][&partitioner=<partitioner>][&use_secondary=true|false]] */
private void setLocationFromUri(String location) throws IOException
{
try
{
if (!location.startsWith("cql://"))
throw new Exception("Bad scheme: " + location);
String[] urlParts = location.split("\\?");
if (urlParts.length > 1)
{
Map<String, String> urlQuery = getQueryMap(urlParts[1]);
// each page row size
if (urlQuery.containsKey("page_size"))
pageSize = Integer.parseInt(urlQuery.get("page_size"));
// input query select columns
if (urlQuery.containsKey("columns"))
columns = urlQuery.get("columns");
// output prepared statement
if (urlQuery.containsKey("output_query"))
outputQuery = urlQuery.get("output_query");
// user defined where clause
if (urlQuery.containsKey("where_clause"))
whereClause = urlQuery.get("where_clause");
//split size
if (urlQuery.containsKey("split_size"))
splitSize = Integer.parseInt(urlQuery.get("split_size"));
if (urlQuery.containsKey("partitioner"))
partitionerClass = urlQuery.get("partitioner");
if (urlQuery.containsKey("use_secondary"))
usePartitionFilter = Boolean.parseBoolean(urlQuery.get("use_secondary"));
}
String[] parts = urlParts[0].split("/+");
String[] credentialsAndKeyspace = parts[1].split("@");
if (credentialsAndKeyspace.length > 1)
{
String[] credentials = credentialsAndKeyspace[0].split(":");
username = credentials[0];
password = credentials[1];
keyspace = credentialsAndKeyspace[1];
}
else
{
keyspace = parts[1];
}
column_family = parts[2];
}
catch (Exception e)
{
throw new IOException("Expected 'cql://[username:password@]<keyspace>/<columnfamily>" +
"[?[page_size=<size>][&columns=<col1,col2>][&output_query=<prepared_statement>]" +
"[&where_clause=<clause>][&split_size=<size>][&partitioner=<partitioner>][&use_secondary=true|false]]': " + e.getMessage());
}
}
/**
* Return cql where clauses for the corresponding partition filter. Make sure the data format matches
* Only support the following Pig data types: int, long, float, double, boolean and chararray
* */
private String partitionFilterToWhereClauseString(Expression expression)
{
Expression.BinaryExpression be = (Expression.BinaryExpression) expression;
String name = be.getLhs().toString();
String value = be.getRhs().toString();
OpType op = expression.getOpType();
String opString = op.toString();
switch (op)
{
case OP_EQ:
opString = " = ";
case OP_GE:
case OP_GT:
case OP_LE:
case OP_LT:
return String.format("%s %s %s", name, opString, value);
case OP_AND:
return String.format("%s AND %s", partitionFilterToWhereClauseString(be.getLhs()), partitionFilterToWhereClauseString(be.getRhs()));
default:
throw new RuntimeException("Unsupported expression type: " + opString);
}
}
}