io.lettuce.core.support

Class AsyncConnectionPoolSupport

java.lang.Object

io.lettuce.core.support.AsyncConnectionPoolSupport

public abstract class AsyncConnectionPoolSupport
extends Object

Asynchronous connection pool support for BoundedAsyncPool. Connection pool creation requires a Supplier that connects asynchronously to Redis. The pool can allocate either wrapped or direct connections.

• Wrapped instances will return the connection back to the pool when called StatefulConnection.close()/ StatefulConnection.closeAsync().
• Regular connections need to be returned to the pool with AsyncPool.release(Object)

Lettuce connections are designed to be thread-safe so one connection can be shared amongst multiple threads and Lettuce connections auto-reconnect by default. Connection pooling with Lettuce can be required when you're invoking Redis operations in multiple threads and you use

• blocking commands such as BLPOP.
• transactions BLPOP.
• command batching.

Transactions and command batching affect connection state. Blocking commands won't propagate queued commands to Redis until the blocking command is completed.

Example

 // application initialization
 RedisClusterClient clusterClient = RedisClusterClient.create(RedisURI.create(host, port));

 AsyncPool<StatefulRedisConnection<String, String>> pool = AsyncConnectionPoolSupport
         .createBoundedObjectPool(() -> clusterClient.connectAsync(), BoundedPoolConfig.create());

 // executing work
 CompletableFuture<String> pingResponse = pool.acquire().thenCompose(c -> {

     return c.async().ping().whenComplete((s, throwable) -> pool.release(c));
 });

 // terminating
 CompletableFuture<Void> poolClose = pool.closeAsync();

 // after poolClose completes:
 CompletableFuture<Void> closeFuture = clusterClient.shutdown();
 

Since:

5.1

Author:

Mark Paluch

Method Summary

Modifier and Type	Method and Description
static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T>	createBoundedObjectPool(Supplier<CompletionStage<T>> connectionSupplier, BoundedPoolConfig config) Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.
static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T>	createBoundedObjectPool(Supplier<CompletionStage<T>> connectionSupplier, BoundedPoolConfig config, boolean wrapConnections) Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.
static <T extends StatefulConnection<?,?>> CompletionStage<BoundedAsyncPool<T>>	createBoundedObjectPoolAsync(Supplier<CompletionStage<T>> connectionSupplier, BoundedPoolConfig config) Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.
static <T extends StatefulConnection<?,?>> CompletionStage<BoundedAsyncPool<T>>	createBoundedObjectPoolAsync(Supplier<CompletionStage<T>> connectionSupplier, BoundedPoolConfig config, boolean wrapConnections) Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.
protected static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T>	doCreatePool(Supplier<CompletionStage<T>> connectionSupplier, BoundedPoolConfig config, boolean wrapConnections)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

createBoundedObjectPool

public static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T> createBoundedObjectPool(Supplier<CompletionStage<T>> connectionSupplier,
                                                                                              BoundedPoolConfig config)

Create and initialize asynchronously a new BoundedAsyncPool using the Supplier. Allocated instances are wrapped and must not be returned with AsyncPool.release(Object).

Please note that pool initialization (creation of idle connections) cannot be awaited using this method. Use for these purposes createBoundedObjectPoolAsync(Supplier, BoundedPoolConfig) instead. This method will be changed with Lettuce 6 to a blocking method to await pool initialization.

Type Parameters:

T - connection type.

Parameters:

connectionSupplier - must not be null.

config - must not be null.

Returns:

the connection pool.

createBoundedObjectPool

public static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T> createBoundedObjectPool(Supplier<CompletionStage<T>> connectionSupplier,
                                                                                              BoundedPoolConfig config,
                                                                                              boolean wrapConnections)

Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.

Please note that pool initialization (creation of idle connections) cannot be awaited using this method. Use for these purposes createBoundedObjectPoolAsync(Supplier, BoundedPoolConfig, boolean) instead. This method will be changed with Lettuce 6 to a blocking method to await pool initialization.

Type Parameters:

T - connection type.

Parameters:

connectionSupplier - must not be null.

config - must not be null.

wrapConnections - false to return direct connections that need to be returned to the pool using AsyncPool.release(Object). true to return wrapped connection that are returned to the pool when invoking StatefulConnection.close()/StatefulConnection.closeAsync().

Returns:

the connection pool.

createBoundedObjectPoolAsync

public static <T extends StatefulConnection<?,?>> CompletionStage<BoundedAsyncPool<T>> createBoundedObjectPoolAsync(Supplier<CompletionStage<T>> connectionSupplier,
                                                                                                                    BoundedPoolConfig config)

Create and initialize asynchronously a new BoundedAsyncPool using the Supplier. Allocated instances are wrapped and must not be returned with AsyncPool.release(Object).

Type Parameters:

T - connection type.

Parameters:

connectionSupplier - must not be null.

config - must not be null.

Returns:

CompletionStage emitting the connection pool upon completion.

Since:

5.3.3

createBoundedObjectPoolAsync

public static <T extends StatefulConnection<?,?>> CompletionStage<BoundedAsyncPool<T>> createBoundedObjectPoolAsync(Supplier<CompletionStage<T>> connectionSupplier,
                                                                                                                    BoundedPoolConfig config,
                                                                                                                    boolean wrapConnections)

Create and initialize asynchronously a new BoundedAsyncPool using the Supplier.

Type Parameters:

T - connection type.

Parameters:

connectionSupplier - must not be null.

config - must not be null.

wrapConnections - false to return direct connections that need to be returned to the pool using AsyncPool.release(Object). true to return wrapped connection that are returned to the pool when invoking StatefulConnection.close()/StatefulConnection.closeAsync().

Returns:

CompletionStage emitting the connection pool upon completion.

Since:

5.3.3

doCreatePool

protected static <T extends StatefulConnection<?,?>> BoundedAsyncPool<T> doCreatePool(Supplier<CompletionStage<T>> connectionSupplier,
                                                                                      BoundedPoolConfig config,
                                                                                      boolean wrapConnections)