Spring Session provides an API and implementations for managing a user’s session information.
1. Introduction
Spring Session provides an API and implementations for managing a user’s session information while also making it trivial to support clustered sessions without being tied to an application container-specific solution. It also provides transparent integration with:
-
HttpSession: Allows replacing the
HttpSession
in an application container-neutral way, with support for providing session IDs in headers to work with RESTful APIs. -
WebSocket: Provides the ability to keep the
HttpSession
alive when receiving WebSocket messages -
WebSession: Allows replacing the Spring WebFlux’s
WebSession
in an application container-neutral way.
2. What’s New in 2.0
The following list highlights what is new in Spring Session 2.0:
-
Upgraded to Java 8 and Spring Framework 5 as baseline
-
Added support for managing Spring WebFlux’s
WebSession
with RedisReactiveSessionRepository
-
Extracted
SessionRepository
implementations to separate modules -
Improved
Session
andSessionRepository
APIs -
Improved and harmonized configuration support for all supported session stores
-
Added support for configuring default
CookieSerializer
usingSessionCookieConfig
-
Lots of performance improvements and bug fixes
You can find a complete list of what is new by referring to the changelogs of
3. Samples and Guides (Start Here)
To get started with Spring Session, the best place to start is our Sample Applications.
Source | Description | Guide |
---|---|---|
Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to find sessions by username. |
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Demonstrates how to use Spring Session with WebSockets. |
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Demonstrates how to use Spring Session to replace the Spring WebFlux’s |
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Demonstrates how to use Spring Session to customize the Session cookie in a WebFlux based application. |
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Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
Source | Description | Guide |
---|---|---|
Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session and customize the cookie. |
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Demonstrates how to use Spring Session with an existing Spring Security application. |
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Demonstrates how to use Spring Session in a REST application to support authenticating with a header. |
Source | Description | Guide |
---|---|---|
Demonstrates how to use Spring Session to replace the |
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Demonstrates how to use Spring Session to replace the |
Source | Description | Guide |
---|---|---|
Demonstrates how to use Spring Session with Hazelcast in a Java EE application. |
4. Spring Session Modules
In Spring Session 1.x, all of the Spring Session’s SessionRepository
implementations were available within the spring-session
artifact.
While convenient, this approach was not sustainable long-term as more features and SessionRepository
implementations were added to the project.
Starting with Spring Session 2.0, the project has been split into Spring Session Core module and several other modules that carry SessionRepository
implementations and functionality related to the specific data store.
Users of Spring Data should find this arrangement familiar, with Spring Session Core module taking a role equivalent to Spring Data Commons and providing core functionalities and APIs, with other modules containing data store specific implementations.
As part of this split, the Spring Session Data MongoDB and Spring Session Data GemFire modules were moved to separate repositories.
Now the situation with project’s repositories/modules is as follows:
-
-
Hosts the Spring Session Core, Spring Session Data Redis, Spring Session JDBC, and Spring Session Hazelcast modules
-
-
spring-session-data-mongodb
repository-
Hosts the Spring Session Data MongoDB module
-
-
spring-session-data-geode
repository-
Hosts the Spring Session Data Geode and Spring Session Data Geode modules
-
Finally, Spring Session now also provides a Maven BOM (“bill of materials”) module in order to help users with version management concerns:
-
-
Hosts the Spring Session BOM module
-
5. HttpSession
Integration
Spring Session provides transparent integration with HttpSession
.
This means that developers can switch the HttpSession
implementation out with an implementation that is backed by Spring Session.
5.1. Why Spring Session and HttpSession
?
We have already mentioned that Spring Session provides transparent integration with HttpSession
, but what benefits do we get out of this?
-
Clustered Sessions: Spring Session makes it trivial to support clustered sessions without being tied to an application container specific solution.
-
RESTful APIs: Spring Session lets providing session IDs in headers work with RESTful APIs
5.2. HttpSession
with Redis
Using Spring Session with HttpSession
is enabled by adding a Servlet Filter before anything that uses the HttpSession
.
You can choose from enabling this by using either:
5.2.1. Redis Java-based Configuration
This section describes how to use Redis to back HttpSession
by using Java based configuration.
The HttpSession Sample provides a working sample of how to integrate Spring Session and HttpSession by using Java configuration.
You can read the basic steps for integration in the next few sections, but we encourage you to follow along with the detailed HttpSession Guide when integrating with your own application.
|
Spring Java Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a servlet filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
@EnableRedisHttpSession (1)
public class Config {
@Bean
public LettuceConnectionFactory connectionFactory() {
return new LettuceConnectionFactory(); (2)
}
}
1 | The @EnableRedisHttpSession annotation creates a Spring Bean with the name of springSessionRepositoryFilter that implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by Redis. |
2 | We create a RedisConnectionFactory that connects Spring Session to the Redis Server.
We configure the connection to connect to localhost on the default port (6379).
For more information on configuring Spring Data Redis, see the reference documentation. |
Java Servlet Container Initialization
Our Spring Configuration created a Spring Bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, Spring needs to load our Config
class.
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
Fortunately, Spring Session provides a utility class named AbstractHttpSessionApplicationInitializer
to make both of these steps easy.
The following shows an example:
public class Initializer extends AbstractHttpSessionApplicationInitializer { (1)
public Initializer() {
super(Config.class); (2)
}
}
The name of our class (Initializer ) does not matter. What is important is that we extend AbstractHttpSessionApplicationInitializer .
|
1 | The first step is to extend AbstractHttpSessionApplicationInitializer .
Doing so ensures that the Spring Bean by the name of springSessionRepositoryFilter is registered with our Servlet Container for every request. |
2 | AbstractHttpSessionApplicationInitializer also provides a mechanism to ensure Spring loads our Config . |
5.2.2. Redis XML-based Configuration
This section describes how to use Redis to back HttpSession
by using XML based configuration.
The HttpSession XML Sample provides a working sample of how to integrate Spring Session and HttpSession using XML configuration.
You can read the basic steps for integration in the next few sections, but we encourage you to follow along with the detailed HttpSession XML Guide when integrating with your own application.
|
Spring XML Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a servlet filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
(1)
<context:annotation-config/>
<bean class="org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration"/>
(2)
<bean class="org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory"/>
1 | We use the combination of <context:annotation-config/> and RedisHttpSessionConfiguration because Spring Session does not yet provide XML Namespace support (see gh-104).
This creates a Spring Bean with the name of springSessionRepositoryFilter that implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by Redis. |
2 | We create a RedisConnectionFactory that connects Spring Session to the Redis Server.
We configure the connection to connect to localhost on the default port (6379)
For more information on configuring Spring Data Redis, see the reference documentation. |
XML Servlet Container Initialization
Our Spring Configuration created a Spring Bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, we need to instruct Spring to load our session.xml
configuration.
We can do so with the following configuration:
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring/session.xml
</param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
The ContextLoaderListener
reads the contextConfigLocation and picks up our session.xml configuration.
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
The following snippet performs this last step for us:
<filter>
<filter-name>springSessionRepositoryFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSessionRepositoryFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>ERROR</dispatcher>
</filter-mapping>
The DelegatingFilterProxy
looks up a Bean by the name of springSessionRepositoryFilter
and cast it to a Filter
.
For every request that DelegatingFilterProxy
is invoked, the springSessionRepositoryFilter
is invoked.
5.3. HttpSession
with JDBC
You can use Spring Session with HttpSession
by adding a servlet filter before anything that uses the HttpSession
.
You can choose to do in any of the following ways:
5.3.1. JDBC Java-based Configuration
This section describes how to use a relational database to back HttpSession
when you use Java-based configuration.
The HttpSession JDBC Sample provides a working sample of how to integrate Spring Session and HttpSession by using Java configuration.
You can read the basic steps for integration in the next few sections, but we encouraged you to follow along with the detailed HttpSession JDBC Guide when integrating with your own application.
|
Spring Java Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a Servlet Filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
@EnableJdbcHttpSession (1)
public class Config {
@Bean
public EmbeddedDatabase dataSource() {
return new EmbeddedDatabaseBuilder() (2)
.setType(EmbeddedDatabaseType.H2).addScript("org/springframework/session/jdbc/schema-h2.sql").build();
}
@Bean
public PlatformTransactionManager transactionManager(DataSource dataSource) {
return new DataSourceTransactionManager(dataSource); (3)
}
}
1 | The @EnableJdbcHttpSession annotation creates a Spring Bean with the name of springSessionRepositoryFilter .
That bean implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by a relational database. |
2 | We create a dataSource that connects Spring Session to an embedded instance of an H2 database.
We configure the H2 database to create database tables by using the SQL script that is included in Spring Session. |
3 | We create a transactionManager that manages transactions for previously configured dataSource . |
For additional information on how to configure data access related concerns, see the Spring Framework Reference Documentation.
Java Servlet Container Initialization
Our Spring Configuration created a Spring bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, Spring needs to load our Config
class.
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
Fortunately, Spring Session provides a utility class named AbstractHttpSessionApplicationInitializer
to make both of these steps easy.
The following example shows how to do so:
public class Initializer extends AbstractHttpSessionApplicationInitializer { (1)
public Initializer() {
super(Config.class); (2)
}
}
The name of our class (Initializer) does not matter.
What is important is that we extend AbstractHttpSessionApplicationInitializer .
|
1 | The first step is to extend AbstractHttpSessionApplicationInitializer .
Doing so ensures that the Spring bean named springSessionRepositoryFilter is registered with our Servlet Container for every request. |
2 | AbstractHttpSessionApplicationInitializer also provides a mechanism to ensure Spring loads our Config . |
Multiple DataSources
Spring Session provides the @SpringSessionDataSource
qualifier, allowing you to explicitly declare which DataSource
bean should be injected in JdbcIndexedSessionRepository
.
This is particularly useful in scenarios with multiple DataSource
beans present in the application context.
The following example shows how to do so:
@EnableJdbcHttpSession
public class Config {
@Bean
@SpringSessionDataSource (1)
public EmbeddedDatabase firstDataSource() {
return new EmbeddedDatabaseBuilder()
.setType(EmbeddedDatabaseType.H2).addScript("org/springframework/session/jdbc/schema-h2.sql").build();
}
@Bean
public HikariDataSource secondDataSource() {
// ...
}
}
1 | This qualifier declares that firstDataSource is to be used by Spring Session. |
5.3.2. JDBC XML-based Configuration
This section describes how to use a relational database to back HttpSession
when you use XML based configuration.
The HttpSession JDBC XML Sample provides a working sample of how to integrate Spring Session and HttpSession by using XML configuration.
You can read the basic steps for integration in the next few sections, but we encourage you to follow along with the detailed HttpSession JDBC XML Guide when integrating with your own application.
|
Spring XML Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a servlet filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
The following listing shows how to add the following Spring Configuration:
(1)
<context:annotation-config/>
<bean class="org.springframework.session.jdbc.config.annotation.web.http.JdbcHttpSessionConfiguration"/>
(2)
<jdbc:embedded-database id="dataSource" database-name="testdb" type="H2">
<jdbc:script location="classpath:org/springframework/session/jdbc/schema-h2.sql"/>
</jdbc:embedded-database>
(3)
<bean class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<constructor-arg ref="dataSource"/>
</bean>
1 | We use the combination of <context:annotation-config/> and JdbcHttpSessionConfiguration because Spring Session does not yet provide XML Namespace support (see gh-104).
This creates a Spring bean with the name of springSessionRepositoryFilter .
That bean implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by a relational database. |
2 | We create a dataSource that connects Spring Session to an embedded instance of an H2 database.
We configure the H2 database to create database tables by using the SQL script that is included in Spring Session. |
3 | We create a transactionManager that manages transactions for previously configured dataSource . |
For additional information on how to configure data access-related concerns, see the Spring Framework Reference Documentation.
XML Servlet Container Initialization
Our Spring Configuration created a Spring bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, we need to instruct Spring to load our session.xml
configuration.
We do so with the following configuration:
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring/session.xml
</param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
The ContextLoaderListener
reads the contextConfigLocation
and picks up our session.xml configuration.
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
The following snippet performs this last step for us:
<filter>
<filter-name>springSessionRepositoryFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSessionRepositoryFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>ERROR</dispatcher>
</filter-mapping>
The DelegatingFilterProxy
looks up a bean named springSessionRepositoryFilter
and casts it to a Filter
.
For every request on which DelegatingFilterProxy
is invoked, the springSessionRepositoryFilter
is invoked.
5.3.3. JDBC Spring Boot-based Configuration
This section describes how to use a relational database to back HttpSession
when you use Spring Boot.
The HttpSession JDBC Spring Boot Sample provides a working sample of how to integrate Spring Session and HttpSession by using Spring Boot.
You can read the basic steps for integration in the next few sections, but we encourage you to follow along with the detailed HttpSession JDBC Spring Boot Guide when integrating with your own application.
|
Spring Boot Configuration
After adding the required dependencies, we can create our Spring Boot configuration.
Thanks to first-class auto configuration support, setting up Spring Session backed by a relational database is as simple as adding a single configuration property to your application.properties
.
The following listing shows how to do so:
spring.session.store-type=jdbc # Session store type.
If a single Spring Session module is present on the classpath, Spring Boot uses that store implementation automatically. If you have more than one implementation, you must choose the StoreType that you wish to use to store the sessions, as shows above.
Under the hood, Spring Boot applies configuration that is equivalent to manually adding the @EnableJdbcHttpSession
annotation.
This creates a Spring bean with the name of springSessionRepositoryFilter
. That bean implements Filter
.
The filter is in charge of replacing the HttpSession
implementation to be backed by Spring Session.
You can further customize by using application.properties
.
The following listing shows how to do so:
server.servlet.session.timeout= # Session timeout. If a duration suffix is not specified, seconds are used. spring.session.jdbc.initialize-schema=embedded # Database schema initialization mode. spring.session.jdbc.schema=classpath:org/springframework/session/jdbc/schema-@@platform@@.sql # Path to the SQL file to use to initialize the database schema. spring.session.jdbc.table-name=SPRING_SESSION # Name of the database table used to store sessions.
For more information, see the Spring Session portion of the Spring Boot documentation.
Configuring the DataSource
Spring Boot automatically creates a DataSource
that connects Spring Session to an embedded instance of an H2 database.
In a production environment, you need to update your configuration to point to your relational database.
For example, you can include the following in your application.properties:
spring.datasource.url= # JDBC URL of the database. spring.datasource.username= # Login username of the database. spring.datasource.password= # Login password of the database.
For more information, see the Configure a DataSource portion of the Spring Boot documentation.
Servlet Container Initialization
Our Spring Boot Configuration created a Spring bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, Spring needs to load our Config
class.
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
Fortunately, Spring Boot takes care of both of these steps for us.
5.4. HttpSession with Hazelcast
Using Spring Session with HttpSession
is enabled by adding a Servlet Filter before anything that uses the HttpSession
.
This section describes how to use Hazelcast to back HttpSession
by using Java-based configuration.
The Hazelcast Spring Sample provides a working sample of how to integrate Spring Session and HttpSession by using Java configuration.
You can read the basic steps for integration in the next few sections, but we encourage you to follow along with the detailed Hazelcast Spring Guide when integrating with your own application.
|
5.4.1. Spring Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a servlet filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
@EnableHazelcastHttpSession (1)
@Configuration
public class HazelcastHttpSessionConfig {
@Bean
public HazelcastInstance hazelcastInstance() {
Config config = new Config();
MapAttributeConfig attributeConfig = new MapAttributeConfig()
.setName(HazelcastIndexedSessionRepository.PRINCIPAL_NAME_ATTRIBUTE)
.setExtractor(PrincipalNameExtractor.class.getName());
config.getMapConfig(HazelcastIndexedSessionRepository.DEFAULT_SESSION_MAP_NAME) (2)
.addMapAttributeConfig(attributeConfig).addMapIndexConfig(
new MapIndexConfig(HazelcastIndexedSessionRepository.PRINCIPAL_NAME_ATTRIBUTE, false));
SerializerConfig serializerConfig = new SerializerConfig();
serializerConfig.setImplementation(new HazelcastSessionSerializer()).setTypeClass(MapSession.class);
config.getSerializationConfig().addSerializerConfig(serializerConfig); (3)
return Hazelcast.newHazelcastInstance(config); (4)
}
}
1 | The @EnableHazelcastHttpSession annotation creates a Spring bean named springSessionRepositoryFilter that implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by Hazelcast. |
2 | In order to support retrieval of sessions by principal name index, an appropriate ValueExtractor needs to be registered.
Spring Session provides PrincipalNameExtractor for this purpose. |
3 | In order to serialize MapSession objects efficiently, HazelcastSessionSerializer needs to be registered. If this
is not set, Hazelcast will serialize sessions using native Java serialization. |
4 | We create a HazelcastInstance that connects Spring Session to Hazelcast.
By default, the application starts and connects to an embedded instance of Hazelcast.
For more information on configuring Hazelcast, see the reference documentation. |
If HazelcastSessionSerializer is preferred, it needs to be configured for all Hazelcast cluster members before they start.
In a Hazelcast cluster, all members should use the same serialization method for sessions. Also, if Hazelcast Client/Server topology
is used, then both members and clients must use the same serialization method. The serializer can be registered via ClientConfig
with the same SerializerConfiguration of members.
|
5.4.2. Servlet Container Initialization
Our Spring Configuration created a Spring bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, Spring needs to load our SessionConfig
class.
Since our application is already loading Spring configuration by using our SecurityInitializer
class, we can add our SessionConfig
class to it.
The following listing shows how to do so:
public class SecurityInitializer extends AbstractSecurityWebApplicationInitializer {
public SecurityInitializer() {
super(SecurityConfig.class, SessionConfig.class);
}
}
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
It is extremely important that Spring Session’s springSessionRepositoryFilter
is invoked before Spring Security’s springSecurityFilterChain
.
Doing so ensures that the HttpSession
that Spring Security uses is backed by Spring Session.
Fortunately, Spring Session provides a utility class named AbstractHttpSessionApplicationInitializer
that makes this doing so easy.
The following example shows how to do so:
public class Initializer extends AbstractHttpSessionApplicationInitializer {
}
The name of our class (Initializer ) does not matter. What is important is that we extend AbstractHttpSessionApplicationInitializer .
|
By extending AbstractHttpSessionApplicationInitializer
, we ensure that the Spring Bean named springSessionRepositoryFilter
is registered with our servlet container for every request before Spring Security’s springSecurityFilterChain
.
5.5. How HttpSession
Integration Works
Fortunately, both HttpSession
and HttpServletRequest
(the API for obtaining an HttpSession
) are both interfaces.
This means that we can provide our own implementations for each of these APIs.
This section describes how Spring Session provides transparent integration with HttpSession . We offer this content so that you can understand what is happening under the covers. This functionality is already integrated and you do NOT need to implement this logic yourself.
|
First, we create a custom HttpServletRequest
that returns a custom implementation of HttpSession
.
It looks something like the following:
public class SessionRepositoryRequestWrapper extends HttpServletRequestWrapper {
public SessionRepositoryRequestWrapper(HttpServletRequest original) {
super(original);
}
public HttpSession getSession() {
return getSession(true);
}
public HttpSession getSession(boolean createNew) {
// create an HttpSession implementation from Spring Session
}
// ... other methods delegate to the original HttpServletRequest ...
}
Any method that returns an HttpSession
is overridden.
All other methods are implemented by HttpServletRequestWrapper
and delegate to the original HttpServletRequest
implementation.
We replace the HttpServletRequest
implementation by using a servlet Filter
called SessionRepositoryFilter
.
The following pseudocode shows how it works:
public class SessionRepositoryFilter implements Filter {
public doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {
HttpServletRequest httpRequest = (HttpServletRequest) request;
SessionRepositoryRequestWrapper customRequest =
new SessionRepositoryRequestWrapper(httpRequest);
chain.doFilter(customRequest, response, chain);
}
// ...
}
By passing a custom HttpServletRequest
implementation into the FilterChain
, we ensure that anything invoked after our Filter
uses the custom HttpSession
implementation.
This highlights why it is important that Spring Session’s SessionRepositoryFilter
be placed before anything that interacts with the HttpSession
.
5.6. HttpSession
and RESTful APIs
Spring Session can work with RESTful APIs by letting the session be provided in a header.
The REST Sample provides a working sample of how to use Spring Session in a REST application to support authenticating with a header. You can follow the basic steps for integration described in the next few sections, but we encourage you to follow along with the detailed REST Guide when integrating with your own application. |
5.6.1. Spring Configuration
After adding the required dependencies, we can create our Spring configuration.
The Spring configuration is responsible for creating a servlet filter that replaces the HttpSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
@Configuration
@EnableRedisHttpSession (1)
public class HttpSessionConfig {
@Bean
public LettuceConnectionFactory connectionFactory() {
return new LettuceConnectionFactory(); (2)
}
@Bean
public HttpSessionIdResolver httpSessionIdResolver() {
return HeaderHttpSessionIdResolver.xAuthToken(); (3)
}
}
1 | The @EnableRedisHttpSession annotation creates a Spring bean named springSessionRepositoryFilter that implements Filter .
The filter is in charge of replacing the HttpSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by Redis. |
2 | We create a RedisConnectionFactory that connects Spring Session to the Redis Server.
We configure the connection to connect to localhost on the default port (6379).
For more information on configuring Spring Data Redis, see the reference documentation. |
3 | We customize Spring Session’s HttpSession integration to use HTTP headers to convey the current session information instead of cookies. |
5.6.2. Servlet Container Initialization
Our Spring Configuration created a Spring Bean named springSessionRepositoryFilter
that implements Filter
.
The springSessionRepositoryFilter
bean is responsible for replacing the HttpSession
with a custom implementation that is backed by Spring Session.
In order for our Filter
to do its magic, Spring needs to load our Config
class.
We provide the configuration in our Spring MvcInitializer
, as the following example shows:
@Override
protected Class<?>[] getRootConfigClasses() {
return new Class[] { SecurityConfig.class, HttpSessionConfig.class };
}
Last, we need to ensure that our Servlet Container (that is, Tomcat) uses our springSessionRepositoryFilter
for every request.
Fortunately, Spring Session provides a utility class named AbstractHttpSessionApplicationInitializer
that makes doing so easy. To do so, extend the class with the default constructor, as the following example shows:
public class Initializer extends AbstractHttpSessionApplicationInitializer {
}
The name of our class (Initializer ) does not matter. What is important is that we extend AbstractHttpSessionApplicationInitializer .
|
5.7. Using HttpSessionListener
Spring Session supports HttpSessionListener
by translating SessionDestroyedEvent
and SessionCreatedEvent
into HttpSessionEvent
by declaring SessionEventHttpSessionListenerAdapter
.
To use this support, you need to:
-
Ensure your
SessionRepository
implementation supports and is configured to fireSessionDestroyedEvent
andSessionCreatedEvent
. -
Configure
SessionEventHttpSessionListenerAdapter
as a Spring bean. -
Inject every
HttpSessionListener
into theSessionEventHttpSessionListenerAdapter
If you use the configuration support documented in HttpSession
with Redis, all you need to do is register every HttpSessionListener
as a bean.
For example, assume you want to support Spring Security’s concurrency control and need to use HttpSessionEventPublisher
. In that case, you can add HttpSessionEventPublisher
as a bean.
In Java configuration, this might look like the following:
@Configuration
@EnableRedisHttpSession
public class RedisHttpSessionConfig {
@Bean
public HttpSessionEventPublisher httpSessionEventPublisher() {
return new HttpSessionEventPublisher();
}
// ...
}
In XML configuration, this might look like the following:
<bean class="org.springframework.security.web.session.HttpSessionEventPublisher"/>
6. WebSocket Integration
Spring Session provides transparent integration with Spring’s WebSocket support.
Spring Session’s WebSocket support works only with Spring’s WebSocket support. Specifically,it does not work with using JSR-356 directly, because JSR-356 does not have a mechanism for intercepting incoming WebSocket messages. |
6.1. Why Spring Session and WebSockets?
So why do we need Spring Session when we use WebSockets?
Consider an email application that does much of its work through HTTP requests.
However, there is also a chat application embedded within it that works over WebSocket APIs.
If a user is actively chatting with someone, we should not timeout the HttpSession
, since this would be a pretty poor user experience.
However, this is exactly what JSR-356 does.
Another issue is that, according to JSR-356, if the HttpSession
times out, any WebSocket that was created with that HttpSession
and an authenticated user should be forcibly closed.
This means that, if we are actively chatting in our application and are not using the HttpSession, we also do disconnect from our conversation.
6.2. WebSocket Usage
The WebSocket Sample provides a working sample of how to integrate Spring Session with WebSockets. You can follow the basic steps for integration described in the next few headings, but we encourage you to follow along with the detailed WebSocket Guide when integrating with your own application.
6.2.1. HttpSession
Integration
Before using WebSocket integration, you should be sure that you have HttpSession
Integration working first.
6.2.2. Spring Configuration
In a typical Spring WebSocket application, you would implement WebSocketMessageBrokerConfigurer
.
For example, the configuration might look something like the following:
@Configuration
@EnableScheduling
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
@Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/messages").withSockJS();
}
@Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
registry.enableSimpleBroker("/queue/", "/topic/");
registry.setApplicationDestinationPrefixes("/app");
}
}
We can update our configuration to use Spring Session’s WebSocket support. The following example shows how to do so:
@Configuration
@EnableScheduling
@EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractSessionWebSocketMessageBrokerConfigurer<Session> { (1)
@Override
protected void configureStompEndpoints(StompEndpointRegistry registry) { (2)
registry.addEndpoint("/messages").withSockJS();
}
@Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
registry.enableSimpleBroker("/queue/", "/topic/");
registry.setApplicationDestinationPrefixes("/app");
}
}
To hook in the Spring Session support we only need to change two things:
1 | Instead of implementing WebSocketMessageBrokerConfigurer , we extend AbstractSessionWebSocketMessageBrokerConfigurer |
2 | We rename the registerStompEndpoints method to configureStompEndpoints |
What does AbstractSessionWebSocketMessageBrokerConfigurer
do behind the scenes?
-
WebSocketConnectHandlerDecoratorFactory
is added as aWebSocketHandlerDecoratorFactory
toWebSocketTransportRegistration
. This ensures a customSessionConnectEvent
is fired that contains theWebSocketSession
. TheWebSocketSession
is necessary to end any WebSocket connections that are still open when a Spring Session is ended. -
SessionRepositoryMessageInterceptor
is added as aHandshakeInterceptor
to everyStompWebSocketEndpointRegistration
. This ensures that theSession
is added to the WebSocket properties to enable updating the last accessed time. -
SessionRepositoryMessageInterceptor
is added as aChannelInterceptor
to our inboundChannelRegistration
. This ensures that every time an inbound message is received, that the last accessed time of our Spring Session is updated. -
WebSocketRegistryListener
is created as a Spring bean. This ensures that we have a mapping of all of theSession
IDs to the corresponding WebSocket connections. By maintaining this mapping, we can close all the WebSocket connections when a Spring Session (HttpSession) is ended.
7. WebSession Integration
Spring Session provides transparent integration with Spring WebFlux’s WebSession
.
This means that you can switch the WebSession
implementation out with an implementation that is backed by Spring Session.
7.1. Why Spring Session and WebSession?
We have already mentioned that Spring Session provides transparent integration with Spring WebFlux’s WebSession
, but what benefits do we get out of this?
As with HttpSession
, Spring Session makes it trivial to support clustered sessions without being tied to an application container specific solution.
7.2. WebSession with Redis
Using Spring Session with WebSession
is enabled by registering a WebSessionManager
implementation backed by Spring Session’s ReactiveSessionRepository
.
The Spring configuration is responsible for creating a WebSessionManager
that replaces the WebSession
implementation with an implementation backed by Spring Session.
To do so, add the following Spring Configuration:
@EnableRedisWebSession (1)
public class SessionConfiguration {
@Bean
public LettuceConnectionFactory redisConnectionFactory() {
return new LettuceConnectionFactory(); (2)
}
}
1 | The @EnableRedisWebSession annotation creates a Spring bean with the name of webSessionManager . That bean implements the WebSessionManager .
This is what is in charge of replacing the WebSession implementation to be backed by Spring Session.
In this instance, Spring Session is backed by Redis. |
2 | We create a RedisConnectionFactory that connects Spring Session to the Redis Server.
We configure the connection to connect to localhost on the default port (6379)
For more information on configuring Spring Data Redis, see the reference documentation. |
7.3. How WebSession Integration Works
It is considerably easier for Spring Session to integrate with Spring WebFlux and its WebSession
, compared to Servlet API and its HttpSession
.
Spring WebFlux provides the WebSessionStore
API, which presents a strategy for persisting WebSession
.
This section describes how Spring Session provides transparent integration with WebSession . We offer this content so that you can understand what is happening under the covers. This functionality is already integrated and you do NOT need to implement this logic yourself.
|
First, we create a custom SpringSessionWebSession
that delegates to Spring Session’s Session
.
It looks something like the following:
public class SpringSessionWebSession implements WebSession {
enum State {
NEW, STARTED
}
private final S session;
private AtomicReference<State> state = new AtomicReference<>();
SpringSessionWebSession(S session, State state) {
this.session = session;
this.state.set(state);
}
@Override
public void start() {
this.state.compareAndSet(State.NEW, State.STARTED);
}
@Override
public boolean isStarted() {
State value = this.state.get();
return (State.STARTED.equals(value)
|| (State.NEW.equals(value) && !this.session.getAttributes().isEmpty()));
}
@Override
public Mono<Void> changeSessionId() {
return Mono.defer(() -> {
this.session.changeSessionId();
return save();
});
}
// ... other methods delegate to the original Session
}
Next, we create a custom WebSessionStore
that delegates to the ReactiveSessionRepository
and wraps Session
into custom WebSession
implementation, as the following listing shows:
public class SpringSessionWebSessionStore<S extends Session> implements WebSessionStore {
private final ReactiveSessionRepository<S> sessions;
public SpringSessionWebSessionStore(ReactiveSessionRepository<S> reactiveSessionRepository) {
this.sessions = reactiveSessionRepository;
}
// ...
}
To be detected by Spring WebFlux, this custom WebSessionStore
needs to be registered with ApplicationContext
as a bean named webSessionManager
.
For additional information on Spring WebFlux, see the Spring Framework Reference Documentation.
8. Spring Security Integration
Spring Session provides integration with Spring Security.
8.1. Spring Security Remember-me Support
Spring Session provides integration with Spring Security’s Remember-me Authentication. The support:
-
Changes the session expiration length
-
Ensures that the session cookie expires at
Integer.MAX_VALUE
. The cookie expiration is set to the largest possible value, because the cookie is set only when the session is created. If it were set to the same value as the session expiration, the session would get renewed when the user used it but the cookie expiration would not be updated (causing the expiration to be fixed).
To configure Spring Session with Spring Security in Java Configuration, you can use the following listing as a guide:
@Override
protected void configure(HttpSecurity http) throws Exception {
http
// ... additional configuration ...
.rememberMe((rememberMe) -> rememberMe
.rememberMeServices(rememberMeServices())
);
}
@Bean
public SpringSessionRememberMeServices rememberMeServices() {
SpringSessionRememberMeServices rememberMeServices =
new SpringSessionRememberMeServices();
// optionally customize
rememberMeServices.setAlwaysRemember(true);
return rememberMeServices;
}
An XML-based configuration would look something like the following:
<security:http>
<!-- ... -->
<security:form-login />
<security:remember-me services-ref="rememberMeServices"/>
</security:http>
<bean id="rememberMeServices"
class="org.springframework.session.security.web.authentication.SpringSessionRememberMeServices"
p:alwaysRemember="true"/>
8.2. Spring Security Concurrent Session Control
Spring Session provides integration with Spring Security to support its concurrent session control.
This allows limiting the number of active sessions that a single user can have concurrently, but, unlike the default
Spring Security support, this also works in a clustered environment. This is done by providing a custom
implementation of Spring Security’s SessionRegistry
interface.
When using Spring Security’s Java config DSL, you can configure the custom SessionRegistry
through the
SessionManagementConfigurer
, as the following listing shows:
@Configuration
public class SecurityConfiguration<S extends Session> extends WebSecurityConfigurerAdapter {
@Autowired
private FindByIndexNameSessionRepository<S> sessionRepository;
@Override
protected void configure(HttpSecurity http) throws Exception {
// @formatter:off
http
// other config goes here...
.sessionManagement((sessionManagement) -> sessionManagement
.maximumSessions(2)
.sessionRegistry(sessionRegistry())
);
// @formatter:on
}
@Bean
public SpringSessionBackedSessionRegistry<S> sessionRegistry() {
return new SpringSessionBackedSessionRegistry<>(this.sessionRepository);
}
}
This assumes that you have also configured Spring Session to provide a FindByIndexNameSessionRepository
that
returns Session
instances.
When using XML configuration, it would look something like the following listing:
<security:http>
<!-- other config goes here... -->
<security:session-management>
<security:concurrency-control max-sessions="2" session-registry-ref="sessionRegistry"/>
</security:session-management>
</security:http>
<bean id="sessionRegistry"
class="org.springframework.session.security.SpringSessionBackedSessionRegistry">
<constructor-arg ref="sessionRepository"/>
</bean>
This assumes that your Spring Session SessionRegistry
bean is called sessionRegistry
, which is the name used by all
SpringHttpSessionConfiguration
subclasses.
8.3. Limitations
Spring Session’s implementation of Spring Security’s SessionRegistry
interface does not support the getAllPrincipals
method, as this information cannot be retrieved by using Spring Session. This method is never called by Spring Security,
so this affects only applications that access the SessionRegistry
themselves.
9. API Documentation
You can browse the complete Javadoc online. The key APIs are described in the following sections:
9.1. Using Session
A Session
is a simplified Map
of name value pairs.
Typical usage might look like the following listing:
public class RepositoryDemo<S extends Session> {
private SessionRepository<S> repository; (1)
public void demo() {
S toSave = this.repository.createSession(); (2)
(3)
User rwinch = new User("rwinch");
toSave.setAttribute(ATTR_USER, rwinch);
this.repository.save(toSave); (4)
S session = this.repository.findById(toSave.getId()); (5)
(6)
User user = session.getAttribute(ATTR_USER);
assertThat(user).isEqualTo(rwinch);
}
// ... setter methods ...
}
1 | We create a SessionRepository instance with a generic type, S , that extends Session . The generic type is defined in our class. |
2 | We create a new Session by using our SessionRepository and assign it to a variable of type S . |
3 | We interact with the Session . In our example, we demonstrate saving a User to the Session . |
4 | We now save the Session . This is why we needed the generic type S . The SessionRepository only allows saving Session instances that were created or retrieved by using the same SessionRepository . This allows for the SessionRepository to make implementation specific optimizations (that is, writing only attributes that have changed). |
5 | We retrieve the Session from the SessionRepository . |
6 | We obtain the persisted User from our Session without the need for explicitly casting our attribute. |
The Session
API also provides attributes related to the Session
instance’s expiration.
Typical usage might look like the following listing:
public class ExpiringRepositoryDemo<S extends Session> {
private SessionRepository<S> repository; (1)
public void demo() {
S toSave = this.repository.createSession(); (2)
// ...
toSave.setMaxInactiveInterval(Duration.ofSeconds(30)); (3)
this.repository.save(toSave); (4)
S session = this.repository.findById(toSave.getId()); (5)
// ...
}
// ... setter methods ...
}
1 | We create a SessionRepository instance with a generic type, S , that extends Session . The generic type is defined in our class. |
2 | We create a new Session by using our SessionRepository and assign it to a variable of type S . |
3 | We interact with the Session .
In our example, we demonstrate updating the amount of time the Session can be inactive before it expires. |
4 | We now save the Session .
This is why we needed the generic type, S .
The SessionRepository allows saving only Session instances that were created or retrieved using the same SessionRepository .
This allows for the SessionRepository to make implementation specific optimizations (that is, writing only attributes that have changed).
The last accessed time is automatically updated when the Session is saved. |
5 | We retrieve the Session from the SessionRepository .
If the Session were expired, the result would be null. |
9.2. Using SessionRepository
A SessionRepository
is in charge of creating, retrieving, and persisting Session
instances.
If possible, you should not interact directly with a SessionRepository
or a Session
.
Instead, developers should prefer interacting with SessionRepository
and Session
indirectly through the HttpSession
and WebSocket integration.
9.3. Using FindByIndexNameSessionRepository
Spring Session’s most basic API for using a Session
is the SessionRepository
.
This API is intentionally very simple, so that you can easily provide additional implementations with basic functionality.
Some SessionRepository
implementations may also choose to implement FindByIndexNameSessionRepository
.
For example, Spring’s Redis, JDBC, and Hazelcast support libraries all implement FindByIndexNameSessionRepository
.
The FindByIndexNameSessionRepository
provides a method to look up all the sessions with a given index name and index value.
As a common use case that is supported by all provided FindByIndexNameSessionRepository
implementations, you can use a convenient method to look up all the sessions for a particular user.
This is done by ensuring that the session attribute with the name of FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME
is populated with the username.
It is your responsibility to ensure that the attribute is populated, since Spring Session is not aware of the authentication mechanism being used.
An example of how to use this can be seen in the following listing:
String username = "username";
this.session.setAttribute(FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME, username);
Some implementations of FindByIndexNameSessionRepository provide hooks to automatically index other session attributes.
For example, many implementations automatically ensure that the current Spring Security user name is indexed with the index name of FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME .
|
Once the session is indexed, you can find by using code similar to the following:
String username = "username";
Map<String, Session> sessionIdToSession = this.sessionRepository.findByPrincipalName(username);
9.4. Using ReactiveSessionRepository
A ReactiveSessionRepository
is in charge of creating, retrieving, and persisting Session
instances in a non-blocking and reactive manner.
If possible, you should not interact directly with a ReactiveSessionRepository
or a Session
.
Instead, you should prefer interacting with ReactiveSessionRepository
and Session
indirectly through the WebSession integration.
9.5. Using @EnableSpringHttpSession
You can add the @EnableSpringHttpSession
annotation to a @Configuration
class to expose the SessionRepositoryFilter
as a bean named springSessionRepositoryFilter
.
In order to use the annotation, you must provide a single SessionRepository
bean.
The following example shows how to do so:
@EnableSpringHttpSession
@Configuration
public class SpringHttpSessionConfig {
@Bean
public MapSessionRepository sessionRepository() {
return new MapSessionRepository(new ConcurrentHashMap<>());
}
}
Note that no infrastructure for session expirations is configured for you. This is because things such as session expiration are highly implementation-dependent. This means that, if you need to clean up expired sessions, you are responsible for cleaning up the expired sessions.
9.6. Using @EnableSpringWebSession
You can add the @EnableSpringWebSession
annotation to a @Configuration
class to expose the WebSessionManager
as a bean named webSessionManager
.
To use the annotation, you must provide a single ReactiveSessionRepository
bean.
The following example shows how to do so:
@EnableSpringWebSession
public class SpringWebSessionConfig {
@Bean
public ReactiveSessionRepository reactiveSessionRepository() {
return new ReactiveMapSessionRepository(new ConcurrentHashMap<>());
}
}
Note that no infrastructure for session expirations is configured for you. This is because things such as session expiration are highly implementation-dependent. This means that, if you require cleaning up expired sessions, you are responsible for cleaning up the expired sessions.
9.7. Using RedisIndexedSessionRepository
RedisIndexedSessionRepository
is a SessionRepository
that is implemented by using Spring Data’s RedisOperations
.
In a web environment, this is typically used in combination with SessionRepositoryFilter
.
The implementation supports SessionDestroyedEvent
and SessionCreatedEvent
through SessionMessageListener
.
9.7.1. Instantiating a RedisIndexedSessionRepository
You can see a typical example of how to create a new instance in the following listing:
RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
// ... configure redisTemplate ...
SessionRepository<? extends Session> repository = new RedisIndexedSessionRepository(redisTemplate);
For additional information on how to create a RedisConnectionFactory
, see the Spring Data Redis Reference.
9.7.2. Using @EnableRedisHttpSession
In a web environment, the simplest way to create a new RedisIndexedSessionRepository
is to use @EnableRedisHttpSession
.
You can find complete example usage in the Samples and Guides (Start Here).
You can use the following attributes to customize the configuration:
-
maxInactiveIntervalInSeconds: The amount of time before the session expires, in seconds.
-
redisNamespace: Allows configuring an application specific namespace for the sessions. Redis keys and channel IDs start with the prefix of
<redisNamespace>:
. -
flushMode: Allows specifying when data is written to Redis. The default is only when
save
is invoked onSessionRepository
. A value ofFlushMode.IMMEDIATE
writes to Redis as soon as possible.
9.7.3. Redis TaskExecutor
RedisIndexedSessionRepository
is subscribed to receive events from Redis by using a RedisMessageListenerContainer
.
You can customize the way those events are dispatched by creating a bean named springSessionRedisTaskExecutor
, a bean springSessionRedisSubscriptionExecutor
, or both.
You can find more details on configuring Redis task executors here.
9.7.4. Storage Details
The following sections outline how Redis is updated for each operation. The following example shows an example of creating a new session:
HMSET spring:session:sessions:33fdd1b6-b496-4b33-9f7d-df96679d32fe creationTime 1404360000000 \ maxInactiveInterval 1800 \ lastAccessedTime 1404360000000 \ sessionAttr:attrName someAttrValue \ sessionAttr2:attrName someAttrValue2 EXPIRE spring:session:sessions:33fdd1b6-b496-4b33-9f7d-df96679d32fe 2100 APPEND spring:session:sessions:expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe "" EXPIRE spring:session:sessions:expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe 1800 SADD spring:session:expirations:1439245080000 expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe EXPIRE spring:session:expirations1439245080000 2100
The subsequent sections describe the details.
Saving a Session
Each session is stored in Redis as a Hash
.
Each session is set and updated by using the HMSET
command.
The following example shows how each session is stored:
HMSET spring:session:sessions:33fdd1b6-b496-4b33-9f7d-df96679d32fe creationTime 1404360000000 \ maxInactiveInterval 1800 \ lastAccessedTime 1404360000000 \ sessionAttr:attrName someAttrValue \ sessionAttr2:attrName someAttrValue2
In the preceding example, the following statements are true about the session:
-
The session ID is 33fdd1b6-b496-4b33-9f7d-df96679d32fe.
-
The session was created at 1404360000000 (in milliseconds since midnight of 1/1/1970 GMT).
-
The session expires in 1800 seconds (30 minutes).
-
The session was last accessed at 1404360000000 (in milliseconds since midnight of 1/1/1970 GMT).
-
The session has two attributes. The first is
attrName
, with a value ofsomeAttrValue
. The second session attribute is namedattrName2
, with a value ofsomeAttrValue2
.
Optimized Writes
The Session
instances managed by RedisIndexedSessionRepository
keeps track of the properties that have changed and updates only those.
This means that, if an attribute is written once and read many times, we need to write that attribute only once.
For example, assume the sessionAttr2
session attribute from the lsiting in the preceding section was updated.
The following command would be run upon saving:
HMSET spring:session:sessions:33fdd1b6-b496-4b33-9f7d-df96679d32fe sessionAttr:attrName2 newValue
Session Expiration
An expiration is associated with each session by using the EXPIRE
command, based upon the Session.getMaxInactiveInterval()
.
The following example shows a typical EXPIRE
command:
EXPIRE spring:session:sessions:33fdd1b6-b496-4b33-9f7d-df96679d32fe 2100
Note that the expiration that is set to five minutes after the session actually expires. This is necessary so that the value of the session can be accessed when the session expires. An expiration is set on the session itself five minutes after it actually expires to ensure that it is cleaned up, but only after we perform any necessary processing.
The SessionRepository.findById(String) method ensures that no expired sessions are returned.
This means that you need not check the expiration before using a session.
|
Spring Session relies on the delete and expired keyspace notifications from Redis to fire a SessionDeletedEvent
and a SessionExpiredEvent
, respectively.
SessionDeletedEvent
or SessionExpiredEvent
ensure that resources associated with the Session
are cleaned up.
For example, when you use Spring Session’s WebSocket support, the Redis expired or delete event triggers any WebSocket connections associated with the session to be closed.
Expiration is not tracked directly on the session key itself, since this would mean the session data would no longer be available. Instead, a special session expires key is used. In the preceding example, the expires key is as follows:
APPEND spring:session:sessions:expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe "" EXPIRE spring:session:sessions:expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe 1800
When a session expires key is deleted or expires, the keyspace notification triggers a lookup of the actual session, and a SessionDestroyedEvent
is fired.
One problem with relying on Redis expiration exclusively is that, if the key has not been accessed, Redis makes no guarantee of when the expired event is fired. Specifically, the background task that Redis uses to clean up expired keys is a low-priority task and may not trigger the key expiration. For additional details, see the Timing of Expired Events section in the Redis documentation.
To circumvent the fact that expired events are not guaranteed to happen, we can ensure that each key is accessed when it is expected to expire. This means that, if the TTL is expired on the key, Redis removes the key and fires the expired event when we try to access the key.
For this reason, each session expiration is also tracked to the nearest minute. This lets a background task access the potentially expired sessions to ensure that Redis expired events are fired in a more deterministic fashion. The following example shows these events:
SADD spring:session:expirations:1439245080000 expires:33fdd1b6-b496-4b33-9f7d-df96679d32fe EXPIRE spring:session:expirations1439245080000 2100
The background task then uses these mappings to explicitly request each key. By accessing the key, rather than deleting it, we ensure that Redis deletes the key for us only if the TTL is expired.
We do not explicitly delete the keys, since, in some instances, there may be a race condition that incorrectly identifies a key as expired when it is not. Short of using distributed locks (which would kill our performance), there is no way to ensure the consistency of the expiration mapping. By simply accessing the key, we ensure that the key is only removed if the TTL on that key is expired. |
9.7.5. SessionDeletedEvent
and SessionExpiredEvent
SessionDeletedEvent
and SessionExpiredEvent
are both types of SessionDestroyedEvent
.
RedisIndexedSessionRepository
supports firing a SessionDeletedEvent
when a Session
is deleted or a SessionExpiredEvent
when a Session
expires.
This is necessary to ensure resources associated with the Session
are properly cleaned up.
For example, when integrating with WebSockets, the SessionDestroyedEvent
is in charge of closing any active WebSocket connections.
Firing SessionDeletedEvent
or SessionExpiredEvent
is made available through the SessionMessageListener
, which listens to Redis Keyspace events.
In order for this to work, Redis Keyspace events for Generic commands and Expired events needs to be enabled.
The following example shows how to do so:
redis-cli config set notify-keyspace-events Egx
If you use @EnableRedisHttpSession
, managing the SessionMessageListener
and enabling the necessary Redis Keyspace events is done automatically.
However, in a secured Redis enviornment, the config command is disabled.
This means that Spring Session cannot configure Redis Keyspace events for you.
To disable the automatic configuration, add ConfigureRedisAction.NO_OP
as a bean.
For example, with Java configuration, you can use the following:
@Bean
ConfigureRedisAction configureRedisAction() {
return ConfigureRedisAction.NO_OP;
}
In XML configuration, you can use the following:
<util:constant
static-field="org.springframework.session.data.redis.config.ConfigureRedisAction.NO_OP"/>
9.7.6. Using SessionCreatedEvent
When a session is created, an event is sent to Redis with a channel ID of spring:session:channel:created:33fdd1b6-b496-4b33-9f7d-df96679d32fe
,
where 33fdd1b6-b496-4b33-9f7d-df96679d32fe
is the session ID. The body of the event is the session that was created.
If registered as a MessageListener
(the default), RedisIndexedSessionRepository
then translates the Redis message into a SessionCreatedEvent
.
9.7.7. Viewing the Session in Redis
After installing redis-cli, you can inspect the values in Redis using the redis-cli. For example, you can enter the following into a terminal:
$ redis-cli
redis 127.0.0.1:6379> keys *
1) "spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021" (1)
2) "spring:session:expirations:1418772300000" (2)
1 | The suffix of this key is the session identifier of the Spring Session. |
2 | This key contains all the session IDs that should be deleted at the time 1418772300000 . |
You can also view the attributes of each session. The following example shows how to do so:
redis 127.0.0.1:6379> hkeys spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021
1) "lastAccessedTime"
2) "creationTime"
3) "maxInactiveInterval"
4) "sessionAttr:username"
redis 127.0.0.1:6379> hget spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021 sessionAttr:username
"\xac\xed\x00\x05t\x00\x03rob"
9.8. Using ReactiveRedisSessionRepository
ReactiveRedisSessionRepository
is a ReactiveSessionRepository
that is implemented by using Spring Data’s ReactiveRedisOperations
.
In a web environment, this is typically used in combination with WebSessionStore
.
9.8.1. Instantiating a ReactiveRedisSessionRepository
The following example shows how to create a new instance:
// ... create and configure connectionFactory and serializationContext ...
ReactiveRedisTemplate<String, Object> redisTemplate = new ReactiveRedisTemplate<>(connectionFactory,
serializationContext);
ReactiveSessionRepository<? extends Session> repository = new ReactiveRedisSessionRepository(redisTemplate);
For additional information on how to create a ReactiveRedisConnectionFactory
, see the Spring Data Redis Reference.
9.8.2. Using @EnableRedisWebSession
In a web environment, the simplest way to create a new ReactiveRedisSessionRepository
is to use @EnableRedisWebSession
.
You can use the following attributes to customize the configuration:
-
maxInactiveIntervalInSeconds: The amount of time before the session expires, in seconds
-
redisNamespace: Allows configuring an application specific namespace for the sessions. Redis keys and channel IDs start with q prefix of
<redisNamespace>:
. -
flushMode: Allows specifying when data is written to Redis. The default is only when
save
is invoked onReactiveSessionRepository
. A value ofFlushMode.IMMEDIATE
writes to Redis as soon as possible.
9.8.3. Viewing the Session in Redis
After installing redis-cli, you can inspect the values in Redis using the redis-cli. For example, you can enter the following command into a terminal window:
$ redis-cli
redis 127.0.0.1:6379> keys *
1) "spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021" (1)
1 | The suffix of this key is the session identifier of the Spring Session. |
You can also view the attributes of each session by using the hkeys
command.
The following example shows how to do so:
redis 127.0.0.1:6379> hkeys spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021
1) "lastAccessedTime"
2) "creationTime"
3) "maxInactiveInterval"
4) "sessionAttr:username"
redis 127.0.0.1:6379> hget spring:session:sessions:4fc39ce3-63b3-4e17-b1c4-5e1ed96fb021 sessionAttr:username
"\xac\xed\x00\x05t\x00\x03rob"
9.9. Using MapSessionRepository
The MapSessionRepository
allows for persisting Session
in a Map
, with the key being the Session
ID and the value being the Session
.
You can use the implementation with a ConcurrentHashMap
as a testing or convenience mechanism.
Alternatively, you can use it with distributed Map
implementations. For example, it can be used with Hazelcast.
9.9.1. Instantiating MapSessionRepository
The following example shows how to create a new instance:
SessionRepository<? extends Session> repository = new MapSessionRepository(new ConcurrentHashMap<>());
9.9.2. Using Spring Session and Hazlecast
The Hazelcast Sample is a complete application that demonstrates how to use Spring Session with Hazelcast.
To run it, use the following command:
./gradlew :samples:hazelcast:tomcatRun
The Hazelcast Spring Sample is a complete application that demonstrates how to use Spring Session with Hazelcast and Spring Security.
It includes example Hazelcast MapListener
implementations that support firing SessionCreatedEvent
, SessionDeletedEvent
, and SessionExpiredEvent
.
To run it, use the following command:
./gradlew :samples:hazelcast-spring:tomcatRun
9.10. Using ReactiveMapSessionRepository
The ReactiveMapSessionRepository
allows for persisting Session
in a Map
, with the key being the Session
ID and the value being the Session
.
You can use the implementation with a ConcurrentHashMap
as a testing or convenience mechanism.
Alternatively, you can use it with distributed Map
implementations, with the requirement that the supplied Map
must be non-blocking.
9.11. Using JdbcIndexedSessionRepository
JdbcIndexedSessionRepository
is a SessionRepository
implementation that uses Spring’s JdbcOperations
to store sessions in a relational database.
In a web environment, this is typically used in combination with SessionRepositoryFilter
.
Note that this implementation does not support publishing of session events.
9.11.1. Instantiating a JdbcIndexedSessionRepository
The following example shows how to create a new instance:
JdbcTemplate jdbcTemplate = new JdbcTemplate();
// ... configure jdbcTemplate ...
TransactionTemplate transactionTemplate = new TransactionTemplate();
// ... configure transactionTemplate ...
SessionRepository<? extends Session> repository = new JdbcIndexedSessionRepository(jdbcTemplate,
transactionTemplate);
For additional information on how to create and configure JdbcTemplate
and PlatformTransactionManager
, see the Spring Framework Reference Documentation.
9.11.2. Using @EnableJdbcHttpSession
In a web environment, the simplest way to create a new JdbcIndexedSessionRepository
is to use @EnableJdbcHttpSession
.
You can find complete example usage in the Samples and Guides (Start Here)
You can use the following attributes to customize the configuration:
-
tableName: The name of database table used by Spring Session to store sessions
-
maxInactiveIntervalInSeconds: The amount of time before the session will expire in seconds
Customizing LobHandler
You can customize BLOB handling by creating a bean named springSessionLobHandler
that implements LobHandler
.
Customizing ConversionService
You can customize the default serialization and deserialization of the session by providing a ConversionService
instance.
When working in a typical Spring environment, the default ConversionService
bean (named conversionService
) is automatically picked up and used for serialization and deserialization.
However, you can override the default ConversionService
by providing a bean named springSessionConversionService
.
9.11.3. Storage Details
By default, this implementation uses SPRING_SESSION
and SPRING_SESSION_ATTRIBUTES
tables to store sessions.
Note that you can customize the table name, as already described. In that case, the table used to store attributes is named by using the provided table name suffixed with _ATTRIBUTES
.
If further customizations are needed, you can customize the SQL queries used by the repository by using set*Query
setter methods. In this case, you need to manually configure the sessionRepository
bean.
Due to the differences between the various database vendors, especially when it comes to storing binary data, make sure to use SQL scripts specific to your database.
Scripts for most major database vendors are packaged as org/springframework/session/jdbc/schema-*.sql
, where *
is the target database type.
For example, with PostgreSQL, you can use the following schema script:
CREATE TABLE SPRING_SESSION (
PRIMARY_ID CHAR(36) NOT NULL,
SESSION_ID CHAR(36) NOT NULL,
CREATION_TIME BIGINT NOT NULL,
LAST_ACCESS_TIME BIGINT NOT NULL,
MAX_INACTIVE_INTERVAL INT NOT NULL,
EXPIRY_TIME BIGINT NOT NULL,
PRINCIPAL_NAME VARCHAR(100),
CONSTRAINT SPRING_SESSION_PK PRIMARY KEY (PRIMARY_ID)
);
CREATE UNIQUE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (SESSION_ID);
CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (EXPIRY_TIME);
CREATE INDEX SPRING_SESSION_IX3 ON SPRING_SESSION (PRINCIPAL_NAME);
CREATE TABLE SPRING_SESSION_ATTRIBUTES (
SESSION_PRIMARY_ID CHAR(36) NOT NULL,
ATTRIBUTE_NAME VARCHAR(200) NOT NULL,
ATTRIBUTE_BYTES BYTEA NOT NULL,
CONSTRAINT SPRING_SESSION_ATTRIBUTES_PK PRIMARY KEY (SESSION_PRIMARY_ID, ATTRIBUTE_NAME),
CONSTRAINT SPRING_SESSION_ATTRIBUTES_FK FOREIGN KEY (SESSION_PRIMARY_ID) REFERENCES SPRING_SESSION(PRIMARY_ID) ON DELETE CASCADE
);
With MySQL database, you can use the following script:
CREATE TABLE SPRING_SESSION (
PRIMARY_ID CHAR(36) NOT NULL,
SESSION_ID CHAR(36) NOT NULL,
CREATION_TIME BIGINT NOT NULL,
LAST_ACCESS_TIME BIGINT NOT NULL,
MAX_INACTIVE_INTERVAL INT NOT NULL,
EXPIRY_TIME BIGINT NOT NULL,
PRINCIPAL_NAME VARCHAR(100),
CONSTRAINT SPRING_SESSION_PK PRIMARY KEY (PRIMARY_ID)
) ENGINE=InnoDB ROW_FORMAT=DYNAMIC;
CREATE UNIQUE INDEX SPRING_SESSION_IX1 ON SPRING_SESSION (SESSION_ID);
CREATE INDEX SPRING_SESSION_IX2 ON SPRING_SESSION (EXPIRY_TIME);
CREATE INDEX SPRING_SESSION_IX3 ON SPRING_SESSION (PRINCIPAL_NAME);
CREATE TABLE SPRING_SESSION_ATTRIBUTES (
SESSION_PRIMARY_ID CHAR(36) NOT NULL,
ATTRIBUTE_NAME VARCHAR(200) NOT NULL,
ATTRIBUTE_BYTES BLOB NOT NULL,
CONSTRAINT SPRING_SESSION_ATTRIBUTES_PK PRIMARY KEY (SESSION_PRIMARY_ID, ATTRIBUTE_NAME),
CONSTRAINT SPRING_SESSION_ATTRIBUTES_FK FOREIGN KEY (SESSION_PRIMARY_ID) REFERENCES SPRING_SESSION(PRIMARY_ID) ON DELETE CASCADE
) ENGINE=InnoDB ROW_FORMAT=DYNAMIC;
9.11.4. Transaction Management
All JDBC operations in JdbcIndexedSessionRepository
are performed in a transactional manner.
Transactions are performed with propagation set to REQUIRES_NEW
in order to avoid unexpected behavior due to interference with existing transactions (for example, running a save
operation in a thread that already participates in a read-only transaction).
9.12. Using HazelcastIndexedSessionRepository
HazelcastIndexedSessionRepository
is a SessionRepository
implementation that stores sessions in Hazelcast’s distributed IMap
.
In a web environment, this is typically used in combination with SessionRepositoryFilter
.
9.12.1. Instantiating a HazelcastIndexedSessionRepository
The following example shows how to create a new instance:
Config config = new Config();
// ... configure Hazelcast ...
HazelcastInstance hazelcastInstance = Hazelcast.newHazelcastInstance(config);
HazelcastIndexedSessionRepository repository = new HazelcastIndexedSessionRepository(hazelcastInstance);
For additional information on how to create and configure Hazelcast instance, see the Hazelcast documentation.
9.12.2. Using @EnableHazelcastHttpSession
To use Hazelcast as your backing source for the SessionRepository
, you can add the @EnableHazelcastHttpSession
annotation to a @Configuration
class.
Doing so extends the functionality provided by the @EnableSpringHttpSession
annotation but makes the SessionRepository
for you in Hazelcast.
You must provide a single HazelcastInstance
bean for the configuration to work.
You can find a complete configuration example in the Samples and Guides (Start Here).
9.12.3. Basic Customization
You can use the following attributes on @EnableHazelcastHttpSession
to customize the configuration:
-
maxInactiveIntervalInSeconds: The amount of time before the session expires, in seconds. The default is 1800 seconds (30 minutes)
-
sessionMapName: The name of the distributed
Map
that is used in Hazelcast to store the session data.
9.12.4. Session Events
Using a MapListener
to respond to entries being added, evicted, and removed from the distributed Map
causes these events to trigger publishing of SessionCreatedEvent
, SessionExpiredEvent
, and SessionDeletedEvent
events (respectively) through the ApplicationEventPublisher
.
9.12.5. Storage Details
Sessions are stored in a distributed IMap
in Hazelcast.
The IMap
interface methods are used to get()
and put()
Sessions.
Additionally, the values()
method supports a FindByIndexNameSessionRepository#findByIndexNameAndIndexValue
operation, together with appropriate ValueExtractor
(which needs to be registered with Hazelcast). See the Hazelcast Spring Sample for more details on this configuration.
The expiration of a session in the IMap
is handled by Hazelcast’s support for setting the time to live on an entry when it is put()
into the IMap
. Entries (sessions) that have been idle longer than the time to live are automatically removed from the IMap
.
You should not need to configure any settings such as max-idle-seconds
or time-to-live-seconds
for the IMap
within the Hazelcast configuration.
Note that if you use Hazelcast’s MapStore
to persist your sessions IMap
, the following limitations apply when reloading the sessions from MapStore
:
-
Reloading triggers
EntryAddedListener
results inSessionCreatedEvent
being re-published -
Reloading uses default TTL for a given
IMap
results in sessions losing their original TTL
9.13. Using CookieSerializer
A CookieSerializer
is responsible for defining how the session cookie is written.
Spring Session comes with a default implementation using DefaultCookieSerializer
.
9.13.1. Exposing CookieSerializer
as a bean
Exposing the CookieSerializer
as a Spring bean augments the existing configuration when you use configurations like @EnableRedisHttpSession
.
The following example shows how to do so:
@Bean
public CookieSerializer cookieSerializer() {
DefaultCookieSerializer serializer = new DefaultCookieSerializer();
serializer.setCookieName("JSESSIONID"); (1)
serializer.setCookiePath("/"); (2)
serializer.setDomainNamePattern("^.+?\\.(\\w+\\.[a-z]+)$"); (3)
return serializer;
}
1 | We customize the name of the cookie to be JSESSIONID . |
2 | We customize the path of the cookie to be / (rather than the default of the context root). |
3 | We customize the domain name pattern (a regular expression) to be ^.+?\\.(\\w+\\.[a-z]+)$ .
This allows sharing a session across domains and applications.
If the regular expression does not match, no domain is set and the existing domain is used.
If the regular expression matches, the first grouping is used as the domain.
This means that a request to https://child.example.com sets the domain to example.com .
However, a request to http://localhost:8080/ or https://192.168.1.100:8080/ leaves the cookie unset and, thus, still works in development without any changes being necessary for production. |
You should only match on valid domain characters, since the domain name is reflected in the response. Doing so prevents a malicious user from performing such attacks as HTTP Response Splitting. |
9.13.2. Customizing CookieSerializer
You can customize how the session cookie is written by using any of the following configuration options on the DefaultCookieSerializer
.
-
cookieName
: The name of the cookie to use. Default:SESSION
. -
useSecureCookie
: Specifies whether a secure cookie should be used. Default: Use the value ofHttpServletRequest.isSecure()
at the time of creation. -
cookiePath
: The path of the cookie. Default: The context root. -
cookieMaxAge
: Specifies the max age of the cookie to be set at the time the session is created. Default:-1
, which indicates the cookie should be removed when the browser is closed. -
jvmRoute
: Specifies a suffix to be appended to the session ID and included in the cookie. Used to identify which JVM to route to for session affinity. With some implementations (that is, Redis) this option provides no performance benefit. However, it can help with tracing logs of a particular user. -
domainName
: Allows specifying a specific domain name to be used for the cookie. This option is simple to understand but often requires a different configuration between development and production environments. SeedomainNamePattern
as an alternative. -
domainNamePattern
: A case-insensitive pattern used to extract the domain name from theHttpServletRequest#getServerName()
. The pattern should provide a single grouping that is used to extract the value of the cookie domain. If the regular expression does not match, no domain is set and the existing domain is used. If the regular expression matches, the first grouping is used as the domain. -
sameSite
: The value for theSameSite
cookie directive. To disable the serialization of theSameSite
cookie directive, you may set this value tonull
. Default:Lax
You should only match on valid domain characters, since the domain name is reflected in the response. Doing so prevents a malicious user from performing such attacks as HTTP Response Splitting. |
10. Customing SessionRepository
Implementing a custom SessionRepository
API should be a fairly straightforward task.
Coupling the custom implementation with @EnableSpringHttpSession
support lets you reuse existing Spring Session configuration facilities and infrastructure.
There are, however, a couple of aspects that deserve closer consideration.
During the lifecycle of an HTTP request, the HttpSession
is typically persisted to SessionRepository
twice.
The first persist operation is to ensure that the session is available to the client as soon as the client has access to the session ID, and it is also necessary to write after the session is committed because further modifications to the session might be made.
Having this in mind, we generally recommend that a SessionRepository
implementation keep track of changes to ensure that only deltas are saved.
This is particularly important in highly concurrent environments, where multiple requests operate on the same HttpSession
and, therefore, cause race conditions, with requests overriding each other’s changes to session attributes.
All of the SessionRepository
implementations provided by Spring Session use the described approach to persist session changes and can be used for guidance when you implement custom SessionRepository
.
Note that the same recommendations apply for implementing a custom ReactiveSessionRepository
as well.
In this case, you should use the @EnableSpringWebSession
.
11. Upgrading to 2.x
With the new major release version, the Spring Session team took the opportunity to make some non-passive changes. The focus of these changes is to improve and harmonize Spring Session’s APIs as well as remove the deprecated components.
11.1. Baseline Update
Spring Session 2.0 requires Java 8 and Spring Framework 5.0 as a baseline, since its entire codebase is now based on Java 8 source code. See Upgrading to Spring Framework 5.x for more on upgrading Spring Framework.
11.2. Replaced and Removed Modules
As a part of the project’s splitting of the modules, the existing spring-session
has been replaced with the spring-session-core
module.
The spring-session-core
module holds only the common set of APIs and components, while other modules contain the implementation of the appropriate SessionRepository
and functionality related to that data store.
This applies to several existing modules that were previously a simple dependency aggregator helper module.
With new module arrangement, the following modules actually carry the implementation:
-
Spring Session Data Redis
-
Spring Session JDBC
-
Spring Session Hazelcast
Also, the following modules were removed from the main project repository:
-
Spring Session Data MongoDB
-
Spring Session Data GemFire
Note that these two have moved to separate repositories and continue to be available under new artifact names:
11.3. Replaced and Removed Packages, Classes, and Methods
The following changes were made to packages, classes, and methods:
-
ExpiringSession
API has been merged into theSession
API. -
The
Session
API has been enhanced to make full use of Java 8. -
The
Session
API has been extended withchangeSessionId
support. -
The
SessionRepository
API has been updated to better align with Spring Data method naming conventions. -
AbstractSessionEvent
and its subclasses are no longer constructable without an underlyingSession
object. -
The Redis namespace used by
RedisOperationsSessionRepository
is now fully configurable, instead of being partially configurable. -
Redis configuration support has been updated to avoid registering a Spring Session-specific
RedisTemplate
bean. -
JDBC configuration support has been updated to avoid registering a Spring Session-specific
JdbcTemplate
bean. -
Previously deprecated classes and methods have been removed across the codebase
11.4. Dropped Support
As a part of the changes to HttpSessionStrategy
and its alignment to the counterpart from the reactive world, the support for managing multiple users' sessions in a single browser instance has been removed.
The introduction of a new API to replace this functionality is under consideration for future releases.
12. Spring Session Community
We are glad to consider you a part of our community. The following sections provide additional about how to interact with the Spring Session community.
12.1. Support
You can get help by asking questions on Stack Overflow with the spring-session
tag.
Similarly, we encourage helping others by answering questions on Stack Overflow.
12.2. Source Code
You can find the source code on GitHub at https://github.com/spring-projects/spring-session/
12.3. Issue Tracking
We track issues in GitHub issues at https://github.com/spring-projects/spring-session/issues
12.4. Contributing
We appreciate pull requests.
12.5. License
Spring Session is Open Source software released under the Apache 2.0 license.
13. Minimum Requirements
The minimum requirements for Spring Session are:
-
Java 8+.
-
If you run in a Servlet Container (not required), Servlet 3.1+.
-
If you use other Spring libraries (not required), the minimum required version is Spring 5.0.x.
-
@EnableRedisHttpSession
requires Redis 2.8+. This is necessary to support Session Expiration -
@EnableHazelcastHttpSession
requires Hazelcast 3.6+. This is necessary to supportFindByIndexNameSessionRepository
At its core, Spring Session has a required dependency only on spring-jcl .
For an example of using Spring Session without any other Spring dependencies, see the hazelcast sample application.
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