关于Redis热点key的一些思考

lettuce/src/main/java/com/example/springredislettuce/lettuce/contiguge/RedisMessageListenerFactory.java

@@ -46,6 +46,7 @@ public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {
                     }
                     BeanDefinitionBuilder containerBeanDefinitionBuilder = BeanDefinitionBuilder
                             .genericBeanDefinition(RedisMessageListenerContainer.class);
+                    //设置单机监听主节点的配置
                     RedisStandaloneConfiguration redisStandaloneConfiguration = new RedisStandaloneConfiguration(node.getHost(),node.getPort());
                     LettuceConnectionFactory lettuceConnectionFactory = new LettuceConnectionFactory(redisStandaloneConfiguration);
                     lettuceConnectionFactory.afterPropertiesSet();

spring-redis/src/main/java/com/example/springredis/SpringRedisApplication.java

@@ -1,13 +1,23 @@
 package com.example.springredis;
 
+import com.example.springredis.hotkey.HotKey;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
 
 @SpringBootApplication
+@RestController
 public class SpringRedisApplication {
 
 	public static void main(String[] args) {
 		SpringApplication.run(SpringRedisApplication.class, args);
 	}
 
+
+	@RequestMapping("/hotkey/{key}")
+	public String getHotKey(@PathVariable String key){
+		return HotKey.getHotValue(key);
+	}
 }

spring-redis/src/main/java/com/example/springredis/hotkey/HotKey.java

@@ -0,0 +1,44 @@
+package com.example.springredis.hotkey;
+
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+/**
+ * @program: springBootPractice
+ * @description:
+ * @author: hu_pf
+ * @create: 2019-07-09 18:02
+ **/
+public class HotKey {
+
+    private static Map<String,String> hotKeyMap = new ConcurrentHashMap<>();
+    private static List<String> hotKeyList = new CopyOnWriteArrayList<>();
+
+    static {
+        setHotKey("hu1","1");
+        setHotKey("hu2","2");
+    }
+
+    public static void setHotKey(String key,String value){
+        hotKeyMap.put(key,value);
+        hotKeyList.add(key);
+    }
+
+    public static void updateHotKey(String key,String value){
+        hotKeyMap.put(key,value);
+    }
+
+    public static String getHotValue(String key){
+        return hotKeyMap.get(key);
+    }
+
+    public static void removeHotKey(String key){
+        hotKeyMap.remove(key);
+    }
+
+    public static boolean containKey(String key){
+        return hotKeyList.contains(key);
+    }
+}

spring-redis/src/main/java/com/example/springredis/hotkey/HotKeyAction.java

@@ -0,0 +1,19 @@
+package com.example.springredis.hotkey;
+
+
+public enum HotKeyAction {
+
+    UPDATE(){
+        @Override
+        public void action(String key, String value) {
+            HotKey.updateHotKey(key,value);
+        }
+    },
+    REMOVE(){
+        @Override
+        public void action(String key, String value) {
+            HotKey.removeHotKey(key);
+        }
+    };
+    public abstract void action(String key,String value);
+}

spring-redis/src/main/java/com/example/springredis/redis/KeyExpiredEventMessageListener.java

@@ -1,16 +1,44 @@
 package com.example.springredis.redis;
 
+import com.example.springredis.hotkey.HotKey;
+import com.example.springredis.hotkey.HotKeyAction;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.redis.connection.Message;
 import org.springframework.data.redis.connection.MessageListener;
+import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.stereotype.Component;
 
+
 @Slf4j
 @Component
 public class KeyExpiredEventMessageListener implements MessageListener {
 
+    @Autowired
+    private RedisTemplate redisTemplate;
+
     @Override
     public void onMessage(Message message, byte[] pattern) {
+        String key = new String(message.getChannel());
+        key = key.substring(key.indexOf(":")+1);
+        String action = new String(message.getBody());
+        if (HotKey.containKey(key)){
+            String value = redisTemplate.opsForValue().get(key)+"";
+            switch (action){
+                case "set":
+                    log.info("热点Key:{} 修改",key);
+                    HotKeyAction.UPDATE.action(key,value);
+                    break;
+                case "expired":
+                    log.info("热点Key:{} 到期删除",key);
+                    HotKeyAction.REMOVE.action(key,null);
+                    break;
+                case "del":
+                    log.info("热点Key:{} 删除",key);
+                    HotKeyAction.REMOVE.action(key,null);
+                    break;
+            }
+        }
         log.info("监听到的信息：{},值是:{}", new String(message.getChannel()), new String(message.getBody()));
     }
 }

spring-redis/src/main/java/com/example/springredis/redis/RedisAutoConfiguration.java

@@ -11,8 +11,10 @@
 import org.springframework.data.redis.connection.RedisConnectionFactory;
 import org.springframework.data.redis.connection.jedis.JedisConnection;
 import org.springframework.data.redis.core.RedisOperations;
+import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.data.redis.listener.PatternTopic;
 import org.springframework.data.redis.listener.RedisMessageListenerContainer;
+import org.springframework.data.redis.serializer.StringRedisSerializer;
 import redis.clients.jedis.Jedis;
 
 @Configuration
@@ -48,4 +50,15 @@ public RedisMessageListenerFactory redisMessageListenerFactory(BeanFactory beanF
             return beans;
         }
     }
+
+    @Bean
+    public RedisTemplate<String,String> redisTemplate(RedisConnectionFactory redisConnectionFactory){
+        RedisTemplate<String,String> redisTemplate=new RedisTemplate<>();
+        redisTemplate.setConnectionFactory(redisConnectionFactory);
+        redisTemplate.setKeySerializer(new StringRedisSerializer());
+        redisTemplate.setValueSerializer(new StringRedisSerializer());
+        redisTemplate.afterPropertiesSet();
+        return redisTemplate;
+    }
+
 }