Spring Session auto-configuration expansion

This implementation was inspired in large part by the cache
auto-configuration. In addition to the originally supported Redis, now
Hazelcast, an in-memory map, as well as a no-op option are supported. It
should be easy to extend this to include additional data stores in the
future.

Closes gh-3811

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

@@ -0,0 +1,62 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import javax.annotation.PostConstruct;
+
+import com.hazelcast.core.HazelcastInstance;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.web.ServerProperties;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.session.MapSessionRepository;
+import org.springframework.session.SessionRepository;
+import org.springframework.session.hazelcast.config.annotation.web.http.EnableHazelcastHttpSession;
+import org.springframework.session.hazelcast.config.annotation.web.http.HazelcastHttpSessionConfiguration;
+
+/**
+ * Hazelcast backed session auto-configuration.
+ *
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+@Configuration
+@ConditionalOnClass({ HazelcastInstance.class, HazelcastHttpSessionConfiguration.class })
+@ConditionalOnMissingBean({ SessionRepository.class, HazelcastHttpSessionConfiguration.class })
+@EnableHazelcastHttpSession
+@Conditional(SessionCondition.class)
+class HazelcastSessionConfiguration {
+
+	private final ServerProperties serverProperties;
+
+	private final MapSessionRepository sessionRepository;
+
+	HazelcastSessionConfiguration(ServerProperties serverProperties, MapSessionRepository sessionRepository) {
+		this.serverProperties = serverProperties;
+		this.sessionRepository = sessionRepository;
+	}
+
+	@PostConstruct
+	public void applyConfigurationProperties() {
+		Integer timeout = this.serverProperties.getSession().getTimeout();
+		if (timeout != null) {
+			this.sessionRepository.setDefaultMaxInactiveInterval(timeout);
+		}
+	}
+}

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

@@ -0,0 +1,35 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.session.SessionRepository;
+
+/**
+ * No-op session configuration used to disable Spring Session auto configuration via the
+ * environment.
+ *
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+@Configuration
+@ConditionalOnMissingBean(SessionRepository.class)
+@Conditional(SessionCondition.class)
+class NoOpSessionConfiguration {
+}

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

@@ -0,0 +1,63 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.web.ServerProperties;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.session.SessionRepository;
+import org.springframework.session.data.redis.RedisOperationsSessionRepository;
+import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession;
+import org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration;
+
+/**
+ * Redis backed session auto-configuration.
+ *
+ * @author Andy Wilkinson
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+@Configuration
+@ConditionalOnClass(RedisConnectionFactory.class)
+@ConditionalOnMissingBean({ SessionRepository.class, RedisHttpSessionConfiguration.class })
+@EnableRedisHttpSession
+@Conditional(SessionCondition.class)
+class RedisSessionConfiguration {
+
+	private final ServerProperties serverProperties;
+
+	private final RedisOperationsSessionRepository sessionRepository;
+
+	RedisSessionConfiguration(ServerProperties serverProperties, RedisOperationsSessionRepository sessionRepository) {
+		this.serverProperties = serverProperties;
+		this.sessionRepository = sessionRepository;
+	}
+
+	@PostConstruct
+	public void applyConfigurationProperties() {
+		Integer timeout = this.serverProperties.getSession().getTimeout();
+		if (timeout != null) {
+			this.sessionRepository.setDefaultMaxInactiveInterval(timeout);
+		}
+	}
+
+}

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

@@ -23,64 +23,58 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.boot.autoconfigure.condition.SearchStrategy;
 import org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration;
+import org.springframework.boot.autoconfigure.hazelcast.HazelcastAutoConfiguration;
+import org.springframework.boot.autoconfigure.session.SessionAutoConfiguration.SessionConfigurationImportSelector;
 import org.springframework.boot.autoconfigure.web.ServerProperties;
-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.RedisConnectionFactory;
+import org.springframework.context.annotation.Import;
+import org.springframework.context.annotation.ImportSelector;
+import org.springframework.core.type.AnnotationMetadata;
 import org.springframework.session.Session;
-import org.springframework.session.data.redis.RedisOperationsSessionRepository;
-import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession;
-import org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration;
+import org.springframework.session.SessionRepository;
 
 /**
  * {@link EnableAutoConfiguration Auto-configuration} for Spring Session.
  *
  * @author Andy Wilkinson
+ * @author Tommy Ludwig
  * @since 1.3.0
  */
 @Configuration
 @ConditionalOnClass(Session.class)
-@AutoConfigureAfter(RedisAutoConfiguration.class)
+@ConditionalOnWebApplication
+@ConditionalOnMissingBean(SessionRepository.class)
+@AutoConfigureAfter({ HazelcastAutoConfiguration.class, RedisAutoConfiguration.class })
+@Import(SessionConfigurationImportSelector.class)
 public class SessionAutoConfiguration {
 
-	@EnableConfigurationProperties
-	@ConditionalOnClass(RedisConnectionFactory.class)
-	@ConditionalOnWebApplication
-	@ConditionalOnMissingBean(RedisHttpSessionConfiguration.class)
-	@EnableRedisHttpSession
 	@Configuration
-	public static class SessionRedisHttpConfiguration {
+	@ConditionalOnMissingBean(value = ServerProperties.class, search = SearchStrategy.CURRENT)
+	// Just in case user switches off ServerPropertiesAutoConfiguration
+	public static class ServerPropertiesConfiguration {
 
-		private final ServerProperties serverProperties;
-
-		private final RedisOperationsSessionRepository sessionRepository;
-
-		public SessionRedisHttpConfiguration(ServerProperties serverProperties,
-				RedisOperationsSessionRepository sessionRepository) {
-			this.serverProperties = serverProperties;
-			this.sessionRepository = sessionRepository;
-			applyConfigurationProperties();
+		@Bean
+		// Use the same bean name as the default one for any old webapp
+		public ServerProperties serverProperties() {
+			return new ServerProperties();
 		}
 
-		private void applyConfigurationProperties() {
-			Integer timeout = this.serverProperties.getSession().getTimeout();
-			if (timeout != null) {
-				this.sessionRepository.setDefaultMaxInactiveInterval(timeout);
-			}
-		}
+	}
 
-		@Configuration
-		@ConditionalOnMissingBean(value = ServerProperties.class, search = SearchStrategy.CURRENT)
-		// Just in case user switches off ServerPropertiesAutoConfiguration
-		public static class ServerPropertiesConfiguration {
+	/**
+	 * {@link ImportSelector} to add {@link SessionStoreType} configuration classes.
+	 */
+	static class SessionConfigurationImportSelector implements ImportSelector {
 
-			@Bean
-			// Use the same bean name as the default one for any old webapp
-			public ServerProperties serverProperties() {
-				return new ServerProperties();
+		@Override
+		public String[] selectImports(AnnotationMetadata importingClassMetadata) {
+			SessionStoreType[] types = SessionStoreType.values();
+			String[] imports = new String[types.length];
+			for (int i = 0; i < types.length; i++) {
+				imports[i] = SessionStoreMappings.getConfigurationClass(types[i]);
 			}
-
+			return imports;
 		}
 
 	}

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

@@ -0,0 +1,50 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
+import org.springframework.boot.autoconfigure.condition.SpringBootCondition;
+import org.springframework.boot.bind.RelaxedPropertyResolver;
+import org.springframework.context.annotation.ConditionContext;
+import org.springframework.core.type.AnnotatedTypeMetadata;
+import org.springframework.core.type.AnnotationMetadata;
+
+/**
+ * General condition used by all session auto-configuration classes.
+ *
+ * @author Tommy Ludwig
+ */
+class SessionCondition extends SpringBootCondition {
+
+	@Override
+	public ConditionOutcome getMatchOutcome(ConditionContext context,
+			AnnotatedTypeMetadata metadata) {
+		RelaxedPropertyResolver resolver = new RelaxedPropertyResolver(
+				context.getEnvironment(), "spring.session.store.");
+		if (!resolver.containsProperty("type")) {
+			return ConditionOutcome.match("Automatic session store type");
+		}
+		SessionStoreType sessionStoreType = SessionStoreMappings
+				.getType(((AnnotationMetadata) metadata).getClassName());
+		String value = resolver.getProperty("type").replace("-", "_").toUpperCase();
+		if (value.equals(sessionStoreType.name())) {
+			return ConditionOutcome.match("Session store type " + sessionStoreType);
+		}
+		return ConditionOutcome.noMatch("Session store type " + value);
+	}
+
+}

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

@@ -0,0 +1,57 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * Properties for configuring Spring Session's auto-configuration.
+ *
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+@ConfigurationProperties("spring.session")
+public class SessionProperties {
+
+	private Store store;
+
+	public Store getStore() {
+		return this.store;
+	}
+
+	public void setStore(Store store) {
+		this.store = store;
+	}
+
+	/**
+	 * Session store-specific properties.
+	 */
+	public static class Store {
+		/**
+		 * Session data store type, auto-detected according to the environment by default.
+		 */
+		private SessionStoreType type;
+
+		public SessionStoreType getType() {
+			return this.type;
+		}
+
+		public void setType(SessionStoreType type) {
+			this.type = type;
+		}
+	}
+}

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

@@ -0,0 +1,62 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.util.Assert;
+
+/**
+ * Mappings between {@link SessionStoreType} and {@code @Configuration}.
+ *
+ * @author Tommy Ludwig
+ */
+final class SessionStoreMappings {
+
+	private SessionStoreMappings() {
+	}
+
+	private static final Map<SessionStoreType, Class<?>> MAPPINGS;
+
+	static {
+		Map<SessionStoreType, Class<?>> mappings = new HashMap<SessionStoreType, Class<?>>();
+		mappings.put(SessionStoreType.REDIS, RedisSessionConfiguration.class);
+		mappings.put(SessionStoreType.HAZELCAST, HazelcastSessionConfiguration.class);
+		mappings.put(SessionStoreType.SIMPLE, SimpleSessionConfiguration.class);
+		mappings.put(SessionStoreType.NONE, NoOpSessionConfiguration.class);
+		MAPPINGS = Collections.unmodifiableMap(mappings);
+	}
+
+	public static String getConfigurationClass(SessionStoreType sessionStoreType) {
+		Class<?> configurationClass = MAPPINGS.get(sessionStoreType);
+		Assert.state(configurationClass != null,
+				"Unknown session store type " + sessionStoreType);
+		return configurationClass.getName();
+	}
+
+	public static SessionStoreType getType(String configurationClassName) {
+		for (Map.Entry<SessionStoreType, Class<?>> entry : MAPPINGS.entrySet()) {
+			if (entry.getValue().getName().equals(configurationClassName)) {
+				return entry.getKey();
+			}
+		}
+		throw new IllegalStateException(
+				"Unknown configuration class " + configurationClassName);
+	}
+}

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

@@ -0,0 +1,47 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+/**
+ * Supported Spring Session data store types.
+ *
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+public enum SessionStoreType {
+
+	/**
+	 * Redis backed sessions.
+	 */
+	REDIS,
+
+	/**
+	 * Hazelcast backed sessions.
+	 */
+	HAZELCAST,
+
+	/**
+	 * Simple in-memory map of sessions.
+	 */
+	SIMPLE,
+
+	/**
+	 * No session datastore.
+	 */
+	NONE;
+
+}

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

@@ -0,0 +1,51 @@
+/*
+ * 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.session;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.web.ServerProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.session.ExpiringSession;
+import org.springframework.session.MapSessionRepository;
+import org.springframework.session.SessionRepository;
+import org.springframework.session.config.annotation.web.http.EnableSpringHttpSession;
+
+/**
+ * In-memory session configuration, intended as a fallback.
+ *
+ * @author Tommy Ludwig
+ * @since 1.4.0
+ */
+@Configuration
+@ConditionalOnMissingBean(SessionRepository.class)
+@EnableSpringHttpSession
+@Conditional(SessionCondition.class)
+class SimpleSessionConfiguration {
+
+	@Bean
+	public SessionRepository<ExpiringSession> sessionRepository(ServerProperties serverProperties) {
+		MapSessionRepository sessionRepository = new MapSessionRepository();
+
+		Integer timeout = serverProperties.getSession().getTimeout();
+		if (serverProperties.getSession().getTimeout() != null) {
+			sessionRepository.setDefaultMaxInactiveInterval(timeout);
+		}
+		return sessionRepository;
+	}
+}