package redis.clients.jedis;
import com.sohu.tv.jedis.stat.data.UsefulDataCollector;
import com.sohu.tv.jedis.stat.enums.ClientExceptionType;
import redis.clients.jedis.exceptions.JedisAskDataException;
import redis.clients.jedis.exceptions.JedisClusterException;
import redis.clients.jedis.exceptions.JedisClusterMaxRedirectionsException;
import redis.clients.jedis.exceptions.JedisConnectionException;
import redis.clients.jedis.exceptions.JedisMovedDataException;
import redis.clients.jedis.exceptions.JedisRedirectionException;
import redis.clients.util.JedisClusterCRC16;
import redis.clients.util.SafeEncoder;
public abstract class JedisClusterCommand<T> {
private JedisClusterConnectionHandler connectionHandler;
private int redirections;
private ThreadLocal<Jedis> askConnection = new ThreadLocal<Jedis>();
public JedisClusterCommand(JedisClusterConnectionHandler connectionHandler, int maxRedirections) {
this.connectionHandler = connectionHandler;
this.redirections = maxRedirections;
}
public abstract T execute(Jedis connection);
public T run(String key) {
if (key == null) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster.");
}
return runWithRetries(SafeEncoder.encode(key), this.redirections, false, false);
}
public T run(int keyCount, String... keys) {
if (keys == null || keys.length == 0) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster.");
}
// For multiple keys, only execute if they all share the
// same connection slot.
if (keys.length > 1) {
int slot = JedisClusterCRC16.getSlot(keys[0]);
for (int i = 1; i < keyCount; i++) {
int nextSlot = JedisClusterCRC16.getSlot(keys[i]);
if (slot != nextSlot) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster "
+ "because keys have different slots.");
}
}
}
return runWithRetries(SafeEncoder.encode(keys[0]), this.redirections, false, false);
}
public T runBinary(byte[] key) {
if (key == null) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster.");
}
return runWithRetries(key, this.redirections, false, false);
}
public T runBinary(int keyCount, byte[]... keys) {
if (keys == null || keys.length == 0) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster.");
}
// For multiple keys, only execute if they all share the
// same connection slot.
if (keys.length > 1) {
int slot = JedisClusterCRC16.getSlot(keys[0]);
for (int i = 1; i < keyCount; i++) {
int nextSlot = JedisClusterCRC16.getSlot(keys[i]);
if (slot != nextSlot) {
throw new JedisClusterException("No way to dispatch this command to Redis Cluster "
+ "because keys have different slots.");
}
}
}
return runWithRetries(keys[0], this.redirections, false, false);
}
public T runWithAnyNode() {
Jedis connection = null;
try {
connection = connectionHandler.getConnection();
return execute(connection);
} catch (JedisConnectionException e) {
throw e;
} finally {
releaseConnection(connection);
}
}
private T runWithRetries(byte[] key, int redirections, boolean tryRandomNode, boolean asking) {
if (redirections <= 0) {
JedisClusterMaxRedirectionsException exception = new JedisClusterMaxRedirectionsException("Too many Cluster redirections? key=" + SafeEncoder.encode(key));
//收集
UsefulDataCollector.collectException(exception, "", System.currentTimeMillis(), ClientExceptionType.REDIS_CLUSTER);
throw exception;
}
Jedis connection = null;
try {
if (asking) {
// TODO: Pipeline asking with the original command to make it
// faster....
connection = askConnection.get();
connection.asking();
// if asking success, reset asking flag
asking = false;
} else {
if (tryRandomNode) {
connection = connectionHandler.getConnection();
} else {
connection = connectionHandler.getConnectionFromSlot(JedisClusterCRC16.getSlot(key));
}
}
return execute(connection);
} catch (JedisConnectionException jce) {
if (tryRandomNode) {
// maybe all connection is down
throw jce;
}
// release current connection before recursion
releaseConnection(connection);
connection = null;
// retry with random connection
return runWithRetries(key, redirections - 1, true, asking);
} catch (JedisRedirectionException jre) {
// if MOVED redirection occurred,
if (jre instanceof JedisMovedDataException) {
// it rebuilds cluster's slot cache
// recommended by Redis cluster specification
this.connectionHandler.renewSlotCache(connection);
}
// release current connection before recursion or renewing
releaseConnection(connection);
connection = null;
if (jre instanceof JedisAskDataException) {
asking = true;
askConnection.set(this.connectionHandler.getConnectionFromNode(jre.getTargetNode()));
} else if (jre instanceof JedisMovedDataException) {
} else {
throw new JedisClusterException(jre);
}
return runWithRetries(key, redirections - 1, false, asking);
} finally {
releaseConnection(connection);
}
}
private void releaseConnection(Jedis connection) {
if (connection != null) {
connection.close();
}
}
}