Redis共享Session原理及示例
阿新 • • 發佈:2018-12-10
Redis共享session的作用
- 微服務自身可以保持無狀態,應用例項數量的多少不會影響使用者登入狀態;
- 可實現單點登入的踢出功能,如可以讓上次異地登入的使用者下線;
- session在多個服務或伺服器間共享,實現多站點單點登入(參考SSO服務)
Redis快取session原理簡述
其工作原理,可簡單用圖描述(假設服務A執行有有個多個例項):
Springboot-session結合Redis示例
- 新增maven依賴
<dependency>
<groupId>org.springframework.boot</ groupId>
<artifactId>spring-boot-starter-redis</artifactId>
<version>1.4.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.session</groupId>
<artifactId>spring-session-data-redis</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.session</groupId>
<artifactId>spring-session</artifactId>
<version>1.3.3.RELEASE</version>
</dependency>
- 新增redis配置(application.properties)
spring.redis.database=1 spring.redis.host=localhost spring.redis.password=xxxxx spring.redis.port=6379 # server.port=8080 server.port=8081
- 新增配置類
package com.example.demo.config;
import org.springframework.context.annotation.Configuration;
import org.springframework.session.data.redis.config.annotation.web.http.EnableRedisHttpSession;
@Configuration
@EnableRedisHttpSession
public class RedisSessionConfig {
}
- 新增controller
package com.example.demo.controller;
import java.util.*;
import javax.servlet.http.HttpServletRequest;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
@RestController
@RequestMapping(value = "/")
public class Hello {
@RequestMapping(value = "/set", method = RequestMethod.GET)
public Map<String, Object> firstResp (HttpServletRequest request){
request.getSession().setAttribute("testKey", "testValue");
Map<String, Object> map = new HashMap<>();
map.put("testKey", "testValue");
return map;
}
@RequestMapping(value = "/query", method = RequestMethod.GET)
public Object sessions (HttpServletRequest request){
Map<String, Object> map = new HashMap<>();
map.put("sessionId", request.getSession().getId());
map.put("testKey", request.getSession().getAttribute("testKey"));
return map;
}
}
-
瀏覽器訪問測試
- 啟動兩個springboot程式,分別監聽8080,8081埠
- 瀏覽器分別訪問
http://127.0.0.1:8080/set
,127.0.0.1:8081/query
介面,效果如下:
- 檢視redis中的key
可以看出兩個獨立的應用已經共享了同一個session。