Add support for flush modes using FLUSHDB and FLUSHALL commands.

Closes #2187
Original pull request: #2190.

Author: schnapster

src/main/java/org/springframework/data/redis/connection/DefaultStringRedisConnection.java

@@ -75,6 +75,7 @@
  * @author Andrey Shlykov
  * @author dengliming
  * @author ihaohong
+ * @author Dennis Neufeld
  */
 public class DefaultStringRedisConnection implements StringRedisConnection, DecoratedRedisConnection {
 
@@ -401,6 +402,15 @@ public void flushAll() {
 		delegate.flushAll();
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.redis.connection.RedisServerCommands#flushAll(org.springframework.data.redis.connection.RedisServerCommands.FlushOption)
+	 */
+	@Override
+	public void flushAll(FlushOption option) {
+		delegate.flushAll(option);
+	}
+
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.redis.connection.RedisServerCommands#flushDb()
@@ -410,6 +420,15 @@ public void flushDb() {
 		delegate.flushDb();
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.redis.connection.RedisServerCommands#flushDb(org.springframework.data.redis.connection.RedisServerCommands.FlushOption)
+	 */
+	@Override
+	public void flushDb(FlushOption option) {
+		delegate.flushDb(option);
+	}
+
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.redis.connection.RedisStringCommands#get(byte[])

src/main/java/org/springframework/data/redis/connection/DefaultedRedisClusterConnection.java

@@ -27,6 +27,7 @@
 /**
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Dennis Neufeld
  * @since 2.0
  */
 public interface DefaultedRedisClusterConnection extends RedisClusterConnection, DefaultedRedisConnection {
@@ -73,13 +74,27 @@ default void flushDb(RedisClusterNode node) {
 		serverCommands().flushDb(node);
 	}
 
+	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
+	@Override
+	@Deprecated
+	default void flushDb(RedisClusterNode node, FlushOption option) {
+		serverCommands().flushDb(node, option);
+	}
+
 	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
 	@Override
 	@Deprecated
 	default void flushAll(RedisClusterNode node) {
 		serverCommands().flushAll(node);
 	}
 
+	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
+	@Override
+	@Deprecated
+	default void flushAll(RedisClusterNode node, FlushOption option) {
+		serverCommands().flushAll(node, option);
+	}
+
 	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
 	@Override
 	@Deprecated

src/main/java/org/springframework/data/redis/connection/DefaultedRedisConnection.java

@@ -60,6 +60,7 @@
  * @author Andrey Shlykov
  * @author dengliming
  * @author ihaohong
+ * @author Dennis Neufeld
  * @since 2.0
  */
 public interface DefaultedRedisConnection extends RedisConnection {
@@ -1632,13 +1633,27 @@ default void flushDb() {
 		serverCommands().flushDb();
 	}
 
+	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
+	@Override
+	@Deprecated
+	default void flushDb(FlushOption option) {
+		serverCommands().flushDb(option);
+	}
+
 	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
 	@Override
 	@Deprecated
 	default void flushAll() {
 		serverCommands().flushAll();
 	}
 
+	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
+	@Override
+	@Deprecated
+	default void flushAll(FlushOption option) {
+		serverCommands().flushAll(option);
+	}
+
 	/** @deprecated in favor of {@link RedisConnection#serverCommands()}. */
 	@Override
 	@Deprecated

src/main/java/org/springframework/data/redis/connection/ReactiveClusterServerCommands.java

@@ -20,13 +20,15 @@
 
 import java.util.Properties;
 
+import org.springframework.data.redis.connection.RedisServerCommands.FlushOption;
 import org.springframework.data.redis.core.types.RedisClientInfo;
 
 /**
  * Redis Server commands executed in cluster environment using reactive infrastructure.
  *
  * @author Mark Paluch
  * @author Christoph Strobl
+ * @author Dennis Neufeld
  * @since 2.0
  */
 public interface ReactiveClusterServerCommands extends ReactiveServerCommands {
@@ -91,6 +93,17 @@ public interface ReactiveClusterServerCommands extends ReactiveServerCommands {
 	 */
 	Mono<String> flushDb(RedisClusterNode node);
 
+	/**
+	 * Delete all keys of the currently selected database using the specified flush option.
+	 *
+	 * @param node must not be {@literal null}. {@link Mono} indicating command completion.
+	 * @param option
+	 * @throws IllegalArgumentException when {@code node} is {@literal null}.
+	 * @see RedisServerCommands#flushDb(FlushOption)
+	 * @since 2.6
+	 */
+	Mono<String> flushDb(RedisClusterNode node, FlushOption option);
+
 	/**
 	 * Delete all <b>all keys</b> from <b>all databases</b>.
 	 *
@@ -101,6 +114,18 @@ public interface ReactiveClusterServerCommands extends ReactiveServerCommands {
 	 */
 	Mono<String> flushAll(RedisClusterNode node);
 
+	/**
+	 * Delete all <b>all keys</b> from <b>all databases</b> using the specified flush option.
+	 *
+	 * @param node must not be {@literal null}.
+	 * @param option
+	 * @return {@link Mono} indicating command completion.
+	 * @throws IllegalArgumentException when {@code node} is {@literal null}.
+	 * @see RedisServerCommands#flushAll(FlushOption)
+	 * @since 2.6
+	 */
+	Mono<String> flushAll(RedisClusterNode node, FlushOption option);
+
 	/**
 	 * Load {@literal default} server information like
 	 * <ul>

src/main/java/org/springframework/data/redis/connection/ReactiveServerCommands.java

@@ -21,13 +21,15 @@
 import java.util.Properties;
 import java.util.concurrent.TimeUnit;
 
+import org.springframework.data.redis.connection.RedisServerCommands.FlushOption;
 import org.springframework.data.redis.core.types.RedisClientInfo;
 
 /**
  * Redis Server commands executed using reactive infrastructure.
  *
  * @author Mark Paluch
  * @author Christoph Strobl
+ * @author Dennis Neufeld
  * @since 2.0
  */
 public interface ReactiveServerCommands {
@@ -81,6 +83,16 @@ public interface ReactiveServerCommands {
 	 */
 	Mono<String> flushDb();
 
+	/**
+	 * Delete all keys of the currently selected database using the specified flush option.
+	 *
+	 * @param option
+	 * @return {@link Mono} indicating command completion.
+	 * @see <a href="https://redis.io/commands/flushdb">Redis Documentation: FLUSHDB</a>
+	 * @since 2.6
+	 */
+	Mono<String> flushDb(FlushOption option);
+
 	/**
 	 * Delete all <b>all keys</b> from <b>all databases</b>.
 	 *
@@ -89,6 +101,16 @@ public interface ReactiveServerCommands {
 	 */
 	Mono<String> flushAll();
 
+	/**
+	 * Delete all <b>all keys</b> from <b>all databases</b> using the specified flush option.
+	 *
+	 * @param option
+	 * @return {@link Mono} indicating command completion.
+	 * @see <a href="https://redis.io/commands/flushall">Redis Documentation: FLUSHALL</a>
+	 * @since 2.6
+	 */
+	Mono<String> flushAll(FlushOption option);
+
 	/**
 	 * Load {@literal default} server information like
 	 * <ul>

src/main/java/org/springframework/data/redis/connection/RedisClusterServerCommands.java

@@ -23,6 +23,7 @@
 
 /**
  * @author Mark Paluch
+ * @author Dennis Neufeld
  * @since 2.0
  */
 public interface RedisClusterServerCommands extends RedisServerCommands {
@@ -65,12 +66,28 @@ public interface RedisClusterServerCommands extends RedisServerCommands {
 	 */
 	void flushDb(RedisClusterNode node);
 
+	/**
+	 * @param node must not be {@literal null}.
+	 * @param option
+	 * @see RedisServerCommands#flushDb(FlushOption)
+	 * @since 2.6
+	 */
+	void flushDb(RedisClusterNode node, FlushOption option);
+
 	/**
 	 * @param node must not be {@literal null}.
 	 * @see RedisServerCommands#flushAll()
 	 */
 	void flushAll(RedisClusterNode node);
 
+	/**
+	 * @param node must not be {@literal null}.
+	 * @param option
+	 * @see RedisServerCommands#flushAll(FlushOption)
+	 * @since 2.6
+	 */
+	void flushAll(RedisClusterNode node, FlushOption option);
+
 	/**
 	 * @param node must not be {@literal null}.
 	 * @return

src/main/java/org/springframework/data/redis/connection/RedisServerCommands.java

@@ -29,6 +29,7 @@
  * @author Christoph Strobl
  * @author Thomas Darimont
  * @author Mark Paluch
+ * @author Dennis Neufeld
  */
 public interface RedisServerCommands {
 
@@ -43,6 +44,13 @@ enum MigrateOption {
 		COPY, REPLACE
 	}
 
+	/**
+	 * @since 2.6
+	 */
+	enum FlushOption {
+		SYNC, ASYNC
+	}
+
 	/**
 	 * Start an {@literal Append Only File} rewrite process on server.
 	 *
@@ -101,13 +109,31 @@ default void bgWriteAof() {
 	 */
 	void flushDb();
 
+	/**
+	 * Delete all keys of the currently selected database using the specified flush option.
+	 *
+	 * @param option
+	 * @see <a href="https://redis.io/commands/flushdb">Redis Documentation: FLUSHDB</a>
+	 * @since 2.6
+	 */
+	void flushDb(FlushOption option);
+
 	/**
 	 * Delete all <b>all keys</b> from <b>all databases</b>.
 	 *
 	 * @see <a href="https://redis.io/commands/flushall">Redis Documentation: FLUSHALL</a>
 	 */
 	void flushAll();
 
+	/**
+	 * Delete all <b>all keys</b> from <b>all databases</b> using the specified flush option.
+	 *
+	 * @param option
+	 * @see <a href="https://redis.io/commands/flushall">Redis Documentation: FLUSHALL</a>
+	 * @since 2.6
+	 */
+	void flushAll(FlushOption option);
+
 	/**
 	 * Load {@literal default} server information like
 	 * <ul>