# springboot-session-redis **Repository Path**: mirrors_gspandy/springboot-session-redis ## Basic Information - **Project Name**: springboot-session-redis - **Description**: springboot+springsession+redis实现session共享 - **Primary Language**: Unknown - **License**: Not specified - **Default Branch**: master - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2020-09-24 - **Last Updated**: 2025-10-19 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README # springboot-session-redis springboot+springsession+redis实现session共 * [1、springboot+springsession+redis](#session) * [2、feign框架导致session共享失效](#feign)

springboot+springsession+redis

# 1、引入springsession和springredis的依赖 ``` org.springframework.boot spring-boot-starter-redis org.springframework.session spring-session-data-redis ``` # 2、在启动Application中添加@EnableRedisHttpSession注解 该注解的作用，就是引入springsession管理，同时实现是采用redis管理session的方式。 ``` @SpringBootApplication @EnableRedisHttpSession//增加redissession缓存支持 public class ServiceOneApplication { public static void main(String[] args) { SpringApplication.run(ServiceOneApplication.class,args); } } ``` # 3、修改application.yml，添加redis的配置信息 ``` spring: redis: host: localhost port: 6379 server: port: 8080 ``` # 4、测试controller，分别设置session属性和获取 ``` /** * session设置 * @param key * @param value * @param request * @return */ @ResponseBody @RequestMapping("/setSession/{key}/{value}") public String setSession(@PathVariable String key , @PathVariable String value, HttpServletRequest request){ request.getSession().setAttribute(key,value); Enumeration headers = request.getHeaderNames(); while (headers.hasMoreElements()){ String name = headers.nextElement(); System.out.println(name + ":"+ request.getHeader(name)); } System.out.println(request.getSession().getId()); return request.getSession().getId(); } /** * 读取session * @param key * @param request * @return */ @ResponseBody @RequestMapping("/getSession/{key}") public String getSession(@PathVariable String key ,HttpServletRequest request){ return request.getSession().getAttribute(key) + "---- sessionId:" + request.getSession().getId() ; } ``` 启动两个实例，分别访问发现获取到的sessionid是一致的。 # 5、说明 经过源码分析，springsession+redis关键是通过@EnableRedisHttpSession注解引入的，主要是通过SessionRepositoryFilter进行session的预处理，整个过程还是通过 原生的Cookie中获取SessionID实现。因此我们需要对session做一些特殊操作的时候，需要考虑SessionRepositoryFilter的级别和顺序。

feign框架导致session丢失问题

# 1、引入feign依赖 ``` org.springframework.cloud spring-cloud-starter-feign ``` # 2、声明feignrpc接口 注意：这里feign接口声明只需要能够表达出来调用的url/path/params等信息就可以了，不要携带额外的信息，否则会报错。因为feign本身 是一个rpc框架，目的是为了实现rpc调用，与dubbo等不同，不是接口声明式的，它是restful风格的，因此它要模拟的是浏览器，不是javabean ```aidl //这里不要出现与调用无关的任何信息，哪怕这些信息是真正实现时要用到的。 @FeignClient(name = "session",url = "http://localhost:8090") public interface ControllerInterface { @RequestMapping("/setSession/{key}/{value}") public String setSession(@PathVariable("key") String key , @PathVariable("value") String value); @RequestMapping("/getSession/{key}") public String getSession(@PathVariable(name = "key") String key ); } ``` # 3、在application中增加@EnableFeignClients注解，支持feign ```aidl @SpringBootApplication @EnableRedisHttpSession//增加redissession缓存支持 @EnableFeignClients//增加feign支持，引入feign注解，feign扫描路径可以单独指定(basePackages = ),默认是spring的扫描路径 public class ServiceOneApplication { public static void main(String[] args) { SpringApplication.run(ServiceOneApplication.class,args); } } ``` # 4、在用到的地方，像注入bean一样使用它 ```aidl @Autowired private ControllerInterface controllerInterface; /** * 测试feign的session问题。 * @param key * @return */ @ResponseBody @RequestMapping("/testFeign/{key}") public String testFeign(@PathVariable String key,HttpServletRequest request) { return controllerInterface.getSession(key); } ``` 到这一步，一个普通的feign调用示例就结束了，因为它倾向于restful风格的，因此默认的是无状态的，不会向下游携带额外状态信息，实际开发中我们又需要携带如登录 信息一样的状态信息，该怎么办呢？Feign早就想到了，我们看下源码中的RequestInterceptor怎么说的 ```aidl /** * * Zero or more {@code RequestInterceptors} may be configured for purposes such as adding headers to * all requests. No guarantees are give with regards to the order that interceptors are applied. * Once interceptors are applied, {@link Target#apply(RequestTemplate)} is called to create the * immutable http request sent via {@link Client#execute(Request, feign.Request.Options)}.

* For example:
* 
 * public void apply(RequestTemplate input) {
 *     input.replaceHeader("X-Auth", currentToken);
 * }
 * 
 *
*

Configuration

{@code RequestInterceptors} are configured via {@link * Feign.Builder#requestInterceptors}.

Implementation notes

Do not add * parameters, such as {@code /path/{foo}/bar } in your implementation of {@link * #apply(RequestTemplate)}.
Interceptors are applied after the template's parameters are * {@link RequestTemplate#resolve(java.util.Map) resolved}. This is to ensure that you can * implement signatures are interceptors.


Relationship to Retrofit 1.x

* This class is similar to {@code RequestInterceptor.intercept()}, except that the implementation * can read, remove, or otherwise mutate any part of the request template. */ public interface RequestInterceptor { /** * Called for every request. Add data using methods on the supplied {@link RequestTemplate}. */ void apply(RequestTemplate template); } ``` * Zero or more {@code RequestInterceptors} may be configured for purposes such as adding headers to * all requests. No guarantees are give with regards to the order that interceptors are applied. * Once interceptors are applied, {@link Target#apply(RequestTemplate)} is called to create the * immutable http request sent via {@link Client#execute(Request, feign.Request.Options)}.

* For example: * * public void apply(RequestTemplate input) { * input.replaceHeader("X-Auth", currentToken); * } 注意标红的部分，大意是我们有时候需要一个或者多个RequestInterceptor去配置诸如请求头信息，还给出了授权的头部配置。 到这里我们就明白了，我们需要实现一个RequestInterceptor，在里面将原来的请求头信息付给下游请求，实际上就是Cookie信息， 这样sessionId就传到下游了，也就实现了共享。 # 5、实现RequestInterceptor ```aidl import javax.servlet.http.HttpServletRequest; import java.util.Enumeration; /** * 实现RequestInterceptor，用于设置feign全局请求模板 */ @Component public class FeignRequestIntercepter implements RequestInterceptor { @Override public void apply(RequestTemplate requestTemplate) { //通过RequestContextHolder获取本地请求 RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes(); if (requestAttributes == null){ return; } //获取本地线程绑定的请求对象 HttpServletRequest request = ((ServletRequestAttributes)requestAttributes).getRequest(); //给请求模板附加本地线程头部信息，主要是cookie信息 Enumeration headerNames = request.getHeaderNames(); while (headerNames.hasMoreElements()){ String name = headerNames.nextElement(); requestTemplate.header(name,request.getHeader(name)); } } } ``` # 6、验证 在浏览器中分别输入 http://localhost:8080/setSession/key/hello http://localhost:8090/getSession/key http://localhost:8080/testFeign/key 可以看到，打出的sessionID是相同的，而且都可以获取到session属性。 到这一步就基本解决了session丢失问题。至于网上说的熔断的异步化，导致session信息获取不到的问题，我们这里不做熔断，因此可以不考虑。