feature: support xid load balance (apache#4713)

changes/en-us/develop.md

@@ -4,7 +4,9 @@ Add changes here for all PR submitted to the develop branch.
 <!-- Please add the `changes` to the following location(feature/bugfix/optimize/test) based on the type of PR -->
 
 ### feature：
+  - [[#4661](https://github.com/seata/seata/pull/4713)] support xid load balance
   - [[#4676](https://github.com/seata/seata/pull/4676)] support server to expose Nacos services by mounting SLB
+
 
 ### bugfix：
   - [[#4515](https://github.com/seata/seata/pull/4515)] fix the error of SeataTCCFenceAutoConfiguration when database unused
@@ -36,6 +38,8 @@ Thanks to these contributors for their code commits. Please report an unintended
 - [Ifdevil](https://github.com/Ifdevil)
 - [wingchi-leung](https://github.com/wingchi-leung)
 - [liurong](https://github.com/robynron)
+- [a364176773](https://github.com/a364176773)
 - [2129zxl](https://github.com/2129zxl)
 
+
 Also, we receive many valuable issues, questions and advices from our community. Thanks for you all.

changes/zh-cn/develop.md

@@ -3,8 +3,10 @@
 <!-- 请根据PR的类型添加 `变更记录` 到以下对应位置(feature/bugfix/optimize/test) 下 -->
 
 ### feature：
+  - [[#4661](https://github.com/seata/seata/pull/4713)] 支持根据xid负载均衡算法
   - [[#4676](https://github.com/seata/seata/pull/4676)] 支持Nacos作为注册中心时，server通过挂载SLB暴露服务
 
+
 ### bugfix：
   - [[#4515](https://github.com/seata/seata/pull/4515)] 修复develop分支SeataTCCFenceAutoConfiguration在客户端未使用DB时，启动抛出ClassNotFoundException的问题。
   - [[#4661](https://github.com/seata/seata/pull/4661)] 修复控制台中使用PostgreSQL出现的SQL异常
@@ -36,5 +38,6 @@
 - [Ifdevil](https://github.com/Ifdevil)
 - [wingchi-leung](https://github.com/wingchi-leung)
 - [liurong](https://github.com/robynron)
+- [a364176773](https://github.com/a364176773)
 
 同时，我们收到了社区反馈的很多有价值的issue和建议，非常感谢大家。

common/src/main/java/io/seata/common/DefaultValues.java

@@ -114,7 +114,7 @@ public interface DefaultValues {
 
     boolean DEFAULT_SERVER_ENABLE_CHECK_AUTH = true;
 
-    String DEFAULT_LOAD_BALANCE = "RandomLoadBalance";
+    String DEFAULT_LOAD_BALANCE = "XID";
     int VIRTUAL_NODES_DEFAULT = 10;
 
     /**

discovery/seata-discovery-core/src/main/java/io/seata/discovery/loadbalance/LoadBalanceFactory.java

@@ -35,7 +35,9 @@ public class LoadBalanceFactory {
 
     public static final String LOAD_BALANCE_TYPE = LOAD_BALANCE_PREFIX + "type";
 
-    public static final String RANDOM_LOAD_BALANCE = DEFAULT_LOAD_BALANCE;
+    public static final String RANDOM_LOAD_BALANCE = "RandomLoadBalance";
+
+    public static final String XID_LOAD_BALANCE = "XID";
 
     public static final String ROUND_ROBIN_LOAD_BALANCE = "RoundRobinLoadBalance";
 

discovery/seata-discovery-core/src/main/java/io/seata/discovery/loadbalance/XIDLoadBalance.java

@@ -0,0 +1,68 @@
+/*
+ *  Copyright 1999-2019 Seata.io Group.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package io.seata.discovery.loadbalance;
+
+import static io.seata.discovery.loadbalance.LoadBalanceFactory.XID_LOAD_BALANCE;
+
+
+import java.net.InetSocketAddress;
+import java.util.List;
+import java.util.Objects;
+
+import io.seata.common.loader.EnhancedServiceLoader;
+import io.seata.common.loader.LoadLevel;
+import io.seata.common.util.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * The type xid load balance.
+ *
+ * @author funkye
+ */
+@LoadLevel(name = XID_LOAD_BALANCE)
+public class XIDLoadBalance implements LoadBalance {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(XIDLoadBalance.class);
+
+    private static final LoadBalance RANDOM_LOAD_BALANCE = EnhancedServiceLoader.load(LoadBalance.class,
+        LoadBalanceFactory.RANDOM_LOAD_BALANCE);
+
+    private static final String SPLIT = ":";
+
+    @Override
+    public <T> T select(List<T> invokers, String xid) throws Exception {
+        if (StringUtils.isNotBlank(xid) && xid.contains(SPLIT)) {
+            // ip:port:transactionId -> ip:port
+            String serverAddress = xid.substring(0, xid.lastIndexOf(SPLIT));
+            // ip:port -> port
+            int index = serverAddress.lastIndexOf(SPLIT);
+            int port = Integer.parseInt(serverAddress.substring(index + 1));
+            // ipv4/v6
+            String ip = serverAddress.substring(0, index);
+            InetSocketAddress xidInetSocketAddress = new InetSocketAddress(ip, port);
+            for (T invoker : invokers) {
+                InetSocketAddress inetSocketAddress = (InetSocketAddress)invoker;
+                if (Objects.equals(xidInetSocketAddress, inetSocketAddress)) {
+                    return (T)inetSocketAddress;
+                }
+            }
+            LOGGER.error("not found seata-server channel,xid: {}, try use random load balance", xid);
+        }
+        return RANDOM_LOAD_BALANCE.select(invokers, xid);
+    }
+
+}

discovery/seata-discovery-core/src/main/resources/META-INF/services/io.seata.discovery.loadbalance.LoadBalance

@@ -1,4 +1,5 @@
 io.seata.discovery.loadbalance.RoundRobinLoadBalance
 io.seata.discovery.loadbalance.RandomLoadBalance
 io.seata.discovery.loadbalance.ConsistentHashLoadBalance
-io.seata.discovery.loadbalance.LeastActiveLoadBalance
+io.seata.discovery.loadbalance.LeastActiveLoadBalance
+io.seata.discovery.loadbalance.XIDLoadBalance

discovery/seata-discovery-core/src/test/java/io/seata/discovery/loadbalance/LoadBalanceTest.java

@@ -67,6 +67,26 @@ public void testRoundRobinLoadBalance_select(List<InetSocketAddress> addresses)
         }
     }
 
+    /**
+     * Test xid load load balance select.
+     *
+     * @param addresses the addresses
+     */
+    @ParameterizedTest
+    @MethodSource("addressProvider")
+    public void testXIDLoadBalance_select(List<InetSocketAddress> addresses) throws Exception {
+        XIDLoadBalance loadBalance = new XIDLoadBalance();
+        // ipv4
+        InetSocketAddress inetSocketAddress = loadBalance.select(addresses, "127.0.0.1:8092:123456");
+        Assertions.assertNotNull(inetSocketAddress);
+        // ipv6
+        inetSocketAddress = loadBalance.select(addresses, "2000:0000:0000:0000:0001:2345:6789:abcd:8092:123456");
+        Assertions.assertNotNull(inetSocketAddress);
+        // test not found tc channel
+        inetSocketAddress = loadBalance.select(addresses, "127.0.0.1:8199:123456");
+        Assertions.assertNotEquals(inetSocketAddress.getPort(),8199);
+    }
+
     /**
      * Test consistent hash load load balance select.
      *
@@ -156,7 +176,8 @@ static Stream<List<InetSocketAddress>> addressProvider() {
                         new InetSocketAddress("127.0.0.1", 8092),
                         new InetSocketAddress("127.0.0.1", 8093),
                         new InetSocketAddress("127.0.0.1", 8094),
-                        new InetSocketAddress("127.0.0.1", 8095))
+                        new InetSocketAddress("127.0.0.1", 8095),
+                        new InetSocketAddress("2000:0000:0000:0000:0001:2345:6789:abcd", 8092))
         );
     }
 }

seata-spring-autoconfigure/seata-spring-autoconfigure-client/src/test/java/io/seata/spring/boot/autoconfigure/ClientPropertiesTest.java

@@ -108,7 +108,7 @@ public void testUndoProperties() {
 
     @Test
     public void testLoadBalanceProperties() {
-        assertEquals("RandomLoadBalance", context.getBean(LoadBalanceProperties.class).getType());
+        assertEquals("XID", context.getBean(LoadBalanceProperties.class).getType());
         assertEquals(10, context.getBean(LoadBalanceProperties.class).getVirtualNodes());
     }