Add Redis Cluster support

Introduce configuration options for "spring.redis.cluster.nodes" and
"spring.redis.cluster.max-redirects". Properties such as "timeout" and
others remain available via "spring.redis.timeout" and do not have to be
configured on the cluster itself.

See gh-5128

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/data/redis/RedisAutoConfiguration.java

 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,10 +29,12 @@ import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
+import org.springframework.boot.autoconfigure.data.redis.RedisProperties.Cluster;
 import org.springframework.boot.autoconfigure.data.redis.RedisProperties.Sentinel;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.data.redis.connection.RedisClusterConfiguration;
 import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.data.redis.connection.RedisNode;
 import org.springframework.data.redis.connection.RedisSentinelConfiguration;
@@ -76,6 +78,9 @@ public class RedisAutoConfiguration {
 		@Autowired(required = false)
 		private RedisSentinelConfiguration sentinelConfiguration;
 
+		@Autowired(required = false)
+		private RedisClusterConfiguration clusterConfiguration;
+
 		protected final JedisConnectionFactory applyProperties(
 				JedisConnectionFactory factory) {
 			factory.setHostName(this.properties.getHost());
@@ -104,6 +109,34 @@ public class RedisAutoConfiguration {
 			return null;
 		}
 
+		/**
+		 * Create {@link RedisClusterConfiguration} from {@link RedisProperties.Cluster}.
+		 * 
+		 * 
+		 * @return {@literal null} if no {@link RedisProperties.Cluster} set.
+		 * 
+		 */
+		protected final RedisClusterConfiguration getClusterConfiguration() {
+
+			if (this.clusterConfiguration != null) {
+				return this.clusterConfiguration;
+			}
+
+			if (this.properties.getCluster() == null) {
+				return null;
+			}
+
+			Cluster clusterProperties = this.properties.getCluster();
+			RedisClusterConfiguration config = new RedisClusterConfiguration(
+					clusterProperties.getNodes());
+
+			if (clusterProperties.getMaxRedirects() != null) {
+				config.setMaxRedirects(config.getMaxRedirects().intValue());
+			}
+
+			return config;
+		}
+
 		private List<RedisNode> createSentinels(Sentinel sentinel) {
 			List<RedisNode> sentinels = new ArrayList<RedisNode>();
 			String nodes = sentinel.getNodes();
@@ -135,9 +168,21 @@ public class RedisAutoConfiguration {
 		@ConditionalOnMissingBean(RedisConnectionFactory.class)
 		public JedisConnectionFactory redisConnectionFactory()
 				throws UnknownHostException {
-			return applyProperties(new JedisConnectionFactory(getSentinelConfig()));
+			return applyProperties(createJedisConnectionFactory());
 		}
 
+		private JedisConnectionFactory createJedisConnectionFactory() {
+
+			if (getSentinelConfig() != null) {
+				return new JedisConnectionFactory(getSentinelConfig());
+			}
+
+			if (getClusterConfiguration() != null) {
+				return new JedisConnectionFactory(getClusterConfiguration());
+			}
+
+			return new JedisConnectionFactory();
+		}
 	}
 
 	/**
@@ -156,10 +201,18 @@ public class RedisAutoConfiguration {
 		}
 
 		private JedisConnectionFactory createJedisConnectionFactory() {
-			if (this.properties.getPool() != null) {
-				return new JedisConnectionFactory(getSentinelConfig(), jedisPoolConfig());
+
+			JedisPoolConfig poolConfig = this.properties.getPool() != null ? jedisPoolConfig()
+					: new JedisPoolConfig();
+
+			if (getSentinelConfig() != null) {
+				return new JedisConnectionFactory(getSentinelConfig(), poolConfig);
+			}
+			if (getClusterConfiguration() != null) {
+				return new JedisConnectionFactory(getClusterConfiguration(), poolConfig);
 			}
-			return new JedisConnectionFactory(getSentinelConfig());
+
+			return new JedisConnectionFactory(poolConfig);
 		}
 
 		private JedisPoolConfig jedisPoolConfig() {

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/data/redis/RedisProperties.java

 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,8 @@
 
 package org.springframework.boot.autoconfigure.data.redis;
 
+import java.util.List;
+
 import org.springframework.boot.context.properties.ConfigurationProperties;
 
 /**
@@ -57,6 +59,8 @@ public class RedisProperties {
 
 	private Sentinel sentinel;
 
+	private Cluster cluster;
+
 	public int getDatabase() {
 		return this.database;
 	}
@@ -113,6 +117,14 @@ public class RedisProperties {
 		this.pool = pool;
 	}
 
+	public Cluster getCluster() {
+		return cluster;
+	}
+
+	public void setCluster(Cluster cluster) {
+		this.cluster = cluster;
+	}
+
 	/**
 	 * Pool properties.
 	 */
@@ -176,6 +188,42 @@ public class RedisProperties {
 		}
 	}
 
+	/**
+	 * Cluster properties.
+	 * 
+	 */
+	public static class Cluster {
+
+		/**
+		 * List of host:port pairs. This setting points to an "initial" list of cluster
+		 * nodes and is required to have at least one entry.
+		 */
+		private List<String> nodes;
+
+		/**
+		 * Maximum number of "redirects". Limits the number of redirects to follow when
+		 * executing commands across the cluster. Leave empty to use driver specific
+		 * settings.
+		 */
+		private Integer maxRedirects;
+
+		public List<String> getNodes() {
+			return nodes;
+		}
+
+		public void setNodes(List<String> nodes) {
+			this.nodes = nodes;
+		}
+
+		public Integer getMaxRedirects() {
+			return maxRedirects;
+		}
+
+		public void setMaxRedirects(Integer maxRedirects) {
+			this.maxRedirects = maxRedirects;
+		}
+	}
+
 	/**
 	 * Redis sentinel properties.
 	 */

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/data/redis/RedisAutoConfigurationTests.java

 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -96,7 +96,7 @@ public class RedisAutoConfigurationTests {
 	@Test
 	public void testRedisConfigurationWithSentinel() throws Exception {
 		List<String> sentinels = Arrays.asList("127.0.0.1:26379", "127.0.0.1:26380");
-		if (isAtLeastOneSentinelAvailable(sentinels)) {
+		if (isAtLeastOneNodeAvailable(sentinels)) {
 			load("spring.redis.sentinel.master:mymaster", "spring.redis.sentinel.nodes:"
 					+ StringUtils.collectionToCommaDelimitedString(sentinels));
 			assertThat(this.context.getBean(JedisConnectionFactory.class)
@@ -104,9 +104,22 @@ public class RedisAutoConfigurationTests {
 		}
 	}
 
-	private boolean isAtLeastOneSentinelAvailable(List<String> sentinels) {
-		for (String sentinel : sentinels) {
-			if (isSentinelAvailable(sentinel)) {
+	@Test
+	public void testRedisConfigurationWithCluster() throws Exception {
+
+		List<String> clusterNodes = Arrays.asList("127.0.0.1:27379", "127.0.0.1:27380");
+		if (isAtLeastOneNodeAvailable(clusterNodes)) {
+			load("spring.redis.cluster.nodes[0]:" + clusterNodes.get(0),
+					"spring.redis.cluster.nodes[1]:" + clusterNodes.get(1));
+			assertThat(
+					this.context.getBean(JedisConnectionFactory.class)
+							.getClusterConnection()).isNotNull();
+		}
+	}
+
+	private boolean isAtLeastOneNodeAvailable(List<String> nodes) {
+		for (String node : nodes) {
+			if (isAvailable(node)) {
 				return true;
 			}
 		}
@@ -114,7 +127,7 @@ public class RedisAutoConfigurationTests {
 		return false;
 	}
 
-	private boolean isSentinelAvailable(String node) {
+	private boolean isAvailable(String node) {
 		Jedis jedis = null;
 		try {
 			String[] hostAndPort = node.split(":");

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -685,6 +685,8 @@ content into your application; rather pick only the properties that you need.
 	spring.mongodb.embedded.version=2.6.10 # Version of Mongo to use.
 
 	# REDIS ({sc-spring-boot-autoconfigure}/redis/RedisProperties.{sc-ext}[RedisProperties])
+	spring.redis.cluster.nodes= # List of host:port pairs pointing to an intial collection of cluster nodes. Requires at least one node to connect to the cluster.
+	spring.redis.cluster.max-redirects= # Maximum number of redirects to follow when executing commands across the cluster. Leave empty to use the driver specific value.
 	spring.redis.database=0 # Database index used by the connection factory.
 	spring.redis.host=localhost # Redis server host.
 	spring.redis.password= # Login password of the redis server.