/**
* Redis client binding for YCSB.
*
* All YCSB records are mapped to a Redis *hash field*. For scanning
* operations, all keys are saved (by an arbitrary hash) in a sorted set.
*/
package com.yahoo.ycsb.db;
import com.yahoo.ycsb.DB;
import com.yahoo.ycsb.DBException;
import com.yahoo.ycsb.ByteIterator;
import com.yahoo.ycsb.StringByteIterator;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Properties;
import java.util.Set;
import java.util.Vector;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.Protocol;
public class RedisClient extends DB {
private Jedis jedis;
public static final String HOST_PROPERTY = "redis.host";
public static final String PORT_PROPERTY = "redis.port";
public static final String PASSWORD_PROPERTY = "redis.password";
public static final String INDEX_KEY = "_indices";
public void init() throws DBException {
Properties props = getProperties();
int port;
String portString = props.getProperty(PORT_PROPERTY);
if (portString != null) {
port = Integer.parseInt(portString);
}
else {
port = Protocol.DEFAULT_PORT;
}
String host = props.getProperty(HOST_PROPERTY);
jedis = new Jedis(host, port);
jedis.connect();
String password = props.getProperty(PASSWORD_PROPERTY);
if (password != null) {
jedis.auth(password);
}
}
public void cleanup() throws DBException {
jedis.disconnect();
}
/* Calculate a hash for a key to store it in an index. The actual return
* value of this function is not interesting -- it primarily needs to be
* fast and scattered along the whole space of doubles. In a real world
* scenario one would probably use the ASCII values of the keys.
*/
private double hash(String key) {
return key.hashCode();
}
//XXX jedis.select(int index) to switch to `table`
@Override
public int read(String table, String key, Set<String> fields,
HashMap<String, ByteIterator> result) {
if (fields == null) {
StringByteIterator.putAllAsByteIterators(result, jedis.hgetAll(key));
}
else {
String[] fieldArray = (String[])fields.toArray(new String[fields.size()]);
List<String> values = jedis.hmget(key, fieldArray);
Iterator<String> fieldIterator = fields.iterator();
Iterator<String> valueIterator = values.iterator();
while (fieldIterator.hasNext() && valueIterator.hasNext()) {
result.put(fieldIterator.next(),
new StringByteIterator(valueIterator.next()));
}
assert !fieldIterator.hasNext() && !valueIterator.hasNext();
}
return result.isEmpty() ? 1 : 0;
}
@Override
public int insert(String table, String key, HashMap<String, ByteIterator> values) {
if (jedis.hmset(key, StringByteIterator.getStringMap(values)).equals("OK")) {
jedis.zadd(INDEX_KEY, hash(key), key);
return 0;
}
return 1;
}
@Override
public int delete(String table, String key) {
return jedis.del(key) == 0
&& jedis.zrem(INDEX_KEY, key) == 0
? 1 : 0;
}
@Override
public int update(String table, String key, HashMap<String, ByteIterator> values) {
return jedis.hmset(key, StringByteIterator.getStringMap(values)).equals("OK") ? 0 : 1;
}
@Override
public int scan(String table, String startkey, int recordcount,
Set<String> fields, Vector<HashMap<String, ByteIterator>> result) {
Set<String> keys = jedis.zrangeByScore(INDEX_KEY, hash(startkey),
Double.POSITIVE_INFINITY, 0, recordcount);
HashMap<String, ByteIterator> values;
for (String key : keys) {
values = new HashMap<String, ByteIterator>();
read(table, key, fields, values);
result.add(values);
}
return 0;
}
}