feat: Add support for Redis Sentinels (#216)

* Add support for Redis Sentinels

* Add some comments

common/src/main/java/net/william278/husksync/config/Settings.java

@@ -134,6 +134,17 @@ public class Settings {
     @YamlKey("redis.use_ssl")
     private boolean redisUseSsl = false;
 
+    @YamlComment("If you're using Redis Sentinel, specify the master set name. If you don't know what this is, don't change anything here.")
+    @YamlKey("redis.sentinel.master")
+    private String redisSentinelMaster = "";
+
+    @YamlComment("List of host:port pairs")
+    @YamlKey("redis.sentinel.nodes")
+    private List<String> redisSentinelNodes = new ArrayList<>();
+
+    @YamlKey("redis.sentinel.password")
+    private String redisSentinelPassword = "";
+
 
     // Synchronization settings
     @YamlComment("The mode of data synchronization to use (DELAY or LOCKSTEP). DELAY should be fine for most networks."
@@ -324,6 +335,21 @@ public class Settings {
         return redisUseSsl;
     }
 
+    @NotNull
+    public String getRedisSentinelMaster() {
+        return redisSentinelMaster;
+    }
+
+    @NotNull
+    public List<String> getRedisSentinelNodes() {
+        return redisSentinelNodes;
+    }
+
+    @NotNull
+    public String getRedisSentinelPassword() {
+        return redisSentinelPassword;
+    }
+
     @NotNull
     public DataSyncer.Mode getSyncMode() {
         return syncMode;

common/src/main/java/net/william278/husksync/redis/RedisManager.java

@@ -24,11 +24,9 @@ import net.william278.husksync.data.DataSnapshot;
 import net.william278.husksync.user.User;
 import org.jetbrains.annotations.Blocking;
 import org.jetbrains.annotations.NotNull;
-import redis.clients.jedis.Jedis;
-import redis.clients.jedis.JedisPool;
-import redis.clients.jedis.JedisPoolConfig;
-import redis.clients.jedis.JedisPubSub;
+import redis.clients.jedis.*;
 import redis.clients.jedis.exceptions.JedisException;
+import redis.clients.jedis.util.Pool;
 
 import java.nio.charset.StandardCharsets;
 import java.text.SimpleDateFormat;
@@ -47,7 +45,7 @@ public class RedisManager extends JedisPubSub {
 
     private final HuskSync plugin;
     private final String clusterId;
-    private JedisPool jedisPool;
+    private Pool<Jedis> jedisPool;
     private final Map<UUID, CompletableFuture<Optional<DataSnapshot.Packed>>> pendingRequests;
 
     public RedisManager(@NotNull HuskSync plugin) {
@@ -71,9 +69,16 @@ public class RedisManager extends JedisPubSub {
         config.setMaxIdle(0);
         config.setTestOnBorrow(true);
         config.setTestOnReturn(true);
-        this.jedisPool = password.isEmpty()
-                ? new JedisPool(config, host, port, 0, useSSL)
-                : new JedisPool(config, host, port, 0, password, useSSL);
+        Set<String> redisSentinelNodes = new HashSet<>(plugin.getSettings().getRedisSentinelNodes());
+        if (redisSentinelNodes.isEmpty()) {
+            this.jedisPool = password.isEmpty()
+                    ? new JedisPool(config, host, port, 0, useSSL)
+                    : new JedisPool(config, host, port, 0, password, useSSL);
+        } else {
+            String sentinelPassword = plugin.getSettings().getRedisSentinelPassword();
+            String redisSentinelMaster = plugin.getSettings().getRedisSentinelMaster();
+            this.jedisPool = new JedisSentinelPool(redisSentinelMaster, redisSentinelNodes, password.isEmpty() ? null : password, sentinelPassword.isEmpty() ? null : sentinelPassword);
+        }
 
         // Ping the server to check the connection
         try {