Add session property for ConfigureRedisAction

Add a new property to `RedisSessionProperties` that allows the default
`ConfigureRedisAction` to be changed. Users can still also configure
the action using a `@Bean`.

See gh-17022

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/session/RedisSessionConfiguration.java

@@ -22,13 +22,17 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.session.RedisSessionProperties.ConfigurationStrategy;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.session.SessionRepository;
 import org.springframework.session.data.redis.RedisOperationsSessionRepository;
+import org.springframework.session.data.redis.config.ConfigureNotifyKeyspaceEventsAction;
+import org.springframework.session.data.redis.config.ConfigureRedisAction;
 import org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration;
 
 /**
@@ -62,6 +66,19 @@ class RedisSessionConfiguration {
 			setCleanupCron(redisSessionProperties.getCleanupCron());
 		}
 
+		@Bean
+		@ConditionalOnMissingBean
+		public ConfigureRedisAction configureRedisAction(RedisSessionProperties redisSessionProperties) {
+			ConfigurationStrategy strategy = redisSessionProperties.getConfigurationStrategy();
+			if (strategy == ConfigurationStrategy.NOTIFY_KEYSPACE_EVENTS) {
+				return new ConfigureNotifyKeyspaceEventsAction();
+			}
+			if (strategy == ConfigurationStrategy.NO_OP) {
+				return ConfigureRedisAction.NO_OP;
+			}
+			throw new IllegalStateException("Strategy '" + strategy + "' is not supported.");
+		}
+
 	}
 
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/session/RedisSessionProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2019 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.
@@ -40,6 +40,11 @@ public class RedisSessionProperties {
 	 */
 	private RedisFlushMode flushMode = RedisFlushMode.ON_SAVE;
 
+	/**
+	 * Allows specifying a strategy for configuring and validating Redis.
+	 */
+	private ConfigurationStrategy configurationStrategy = ConfigurationStrategy.NOTIFY_KEYSPACE_EVENTS;
+
 	/**
 	 * Cron expression for expired session cleanup job.
 	 */
@@ -69,4 +74,29 @@ public class RedisSessionProperties {
 		this.cleanupCron = cleanupCron;
 	}
 
+	public ConfigurationStrategy getConfigurationStrategy() {
+		return this.configurationStrategy;
+	}
+
+	public void setConfigurationStrategy(ConfigurationStrategy configurationStrategy) {
+		this.configurationStrategy = configurationStrategy;
+	}
+
+	/**
+	 * Allows specifying a strategy for configuring and validating Redis.
+	 */
+	public enum ConfigurationStrategy {
+
+		/**
+		 * Do nothing.
+		 */
+		NO_OP,
+		/**
+		 * Ensures that Redis Keyspace events for Generic commands and Expired events are
+		 * enabled.
+		 */
+		NOTIFY_KEYSPACE_EVENTS
+
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/session/SessionAutoConfigurationRedisTests.java

@@ -16,6 +16,8 @@
 
 package org.springframework.boot.autoconfigure.session;
 
+import java.util.Map;
+
 import org.junit.jupiter.api.Test;
 import org.testcontainers.junit.jupiter.Container;
 
@@ -28,13 +30,18 @@ import org.springframework.boot.test.context.runner.ContextConsumer;
 import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
 import org.springframework.boot.testsupport.testcontainers.DisabledWithoutDockerTestcontainers;
 import org.springframework.boot.testsupport.testcontainers.RedisContainer;
+import org.springframework.data.redis.connection.RedisConnection;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.session.data.mongo.MongoOperationsSessionRepository;
 import org.springframework.session.data.redis.RedisFlushMode;
 import org.springframework.session.data.redis.RedisOperationsSessionRepository;
+import org.springframework.session.data.redis.config.ConfigureNotifyKeyspaceEventsAction;
+import org.springframework.session.data.redis.config.ConfigureRedisAction;
 import org.springframework.session.hazelcast.HazelcastSessionRepository;
 import org.springframework.session.jdbc.JdbcOperationsSessionRepository;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.entry;
 
 /**
  * Redis specific tests for {@link SessionAutoConfiguration}.
@@ -81,6 +88,34 @@ class SessionAutoConfigurationRedisTests extends AbstractSessionAutoConfiguratio
 				.run(validateSpringSessionUsesRedis("foo:event:0:created:", RedisFlushMode.IMMEDIATE, "0 0 12 * * *"));
 	}
 
+	@Test
+	void redisSessionConfigureNoStrategy() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(RedisAutoConfiguration.class))
+				.withPropertyValues("spring.session.store-type=redis",
+						"spring.session.redis.configuration-strategy=no_op",
+						"spring.redis.port=" + redis.getFirstMappedPort())
+				.run(validateStrategy(ConfigureRedisAction.NO_OP.getClass()));
+	}
+
+	@Test
+	void redisSessionConfigureDefaultStrategy() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(RedisAutoConfiguration.class))
+				.withPropertyValues("spring.session.store-type=redis",
+						"spring.redis.port=" + redis.getFirstMappedPort())
+				.run(validateStrategy(ConfigureNotifyKeyspaceEventsAction.class,
+						entry("notify-keyspace-events", "gxE")));
+	}
+
+	@Test
+	void redisSessionConfigureCustomStrategy() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(RedisAutoConfiguration.class))
+				.withUserConfiguration(MaxEntriesRedisAction.class)
+				.withPropertyValues("spring.session.store-type=redis",
+						"spring.redis.port=" + redis.getFirstMappedPort())
+				.run(validateStrategy(MaxEntriesRedisAction.class, entry("set-max-intset-entries", "1024")));
+
+	}
+
 	private ContextConsumer<AssertableWebApplicationContext> validateSpringSessionUsesRedis(
 			String sessionCreatedChannelPrefix, RedisFlushMode flushMode, String cleanupCron) {
 		return (context) -> {
@@ -94,4 +129,25 @@ class SessionAutoConfigurationRedisTests extends AbstractSessionAutoConfiguratio
 		};
 	}
 
+	private ContextConsumer<AssertableWebApplicationContext> validateStrategy(
+			Class<? extends ConfigureRedisAction> actionClass, Map.Entry... values) {
+		return (context) -> {
+			assertThat(context).hasSingleBean(ConfigureRedisAction.class).hasSingleBean(RedisConnectionFactory.class);
+			assertThat(context.getBean(ConfigureRedisAction.class)).isInstanceOf(actionClass);
+			RedisConnection connection = context.getBean(RedisConnectionFactory.class).getConnection();
+			if (values.length > 0) {
+				assertThat(connection.getConfig("*")).contains(values);
+			}
+		};
+	}
+
+	static class MaxEntriesRedisAction implements ConfigureRedisAction {
+
+		@Override
+		public void configure(RedisConnection connection) {
+			connection.setConfig("set-max-intset-entries", "1024");
+		}
+
+	}
+
 }