tag support multi level

dubbo-common/src/main/java/org/apache/dubbo/common/utils/StringUtils.java

@@ -856,6 +856,23 @@ public static String join(Collection<String> coll, String split) {
         return sb.toString();
     }
 
+    public static String join(final Object[] array, final char delimiter, final int startIndex, final int endIndex) {
+        if (ArrayUtils.isEmpty(array)) {
+            return EMPTY_STRING;
+        }
+        if (endIndex - startIndex <= 0) {
+            return EMPTY_STRING;
+        }
+        StringBuilder sb = new StringBuilder();
+        for (int i = startIndex; i < endIndex; i++) {
+            if (i > 0) {
+                sb.append(delimiter);
+            }
+            sb.append(array[i]);
+        }
+        return sb.toString();
+    }
+
     /**
      * parse key-value pair.
      *

dubbo-common/src/test/java/org/apache/dubbo/common/utils/StringUtilsTest.java

@@ -227,6 +227,10 @@ void testJoin() throws Exception {
         assertEquals(StringUtils.join(s), "123");
         assertEquals(StringUtils.join(s, ','), "1,2,3");
         assertEquals(StringUtils.join(s, ","), "1,2,3");
+        assertEquals(StringUtils.join(s, ',', 0, 1), "1");
+        assertEquals(StringUtils.join(s, ',', 0, 2), "1,2");
+        assertEquals(StringUtils.join(s, ',', 0, 3), "1,2,3");
+        assertEquals("", StringUtils.join(s, ',', 2, 0), "1,2");
     }
 
     @Test
@@ -502,4 +506,4 @@ void testStartsWithIgnoreCase() {
         assertTrue(startsWithIgnoreCase("Dubbo.application.name", "dubbo.application."));
 
     }
-}
+}

dubbo-plugin/dubbo-plugin-router-tag/src/main/java/org/apache/dubbo/rpc/cluster/router/tag/TagStateRouter.java

@@ -36,6 +36,7 @@
 import org.apache.dubbo.rpc.cluster.router.tag.model.TagRouterRule;
 import org.apache.dubbo.rpc.cluster.router.tag.model.TagRuleParser;
 
+import java.util.Map;
 import java.util.Set;
 import java.util.function.Predicate;
 
@@ -52,6 +53,7 @@ public class TagStateRouter<T> extends AbstractStateRouter<T> implements Configu
     public static final String NAME = "TAG_ROUTER";
     private static final ErrorTypeAwareLogger logger = LoggerFactory.getErrorTypeAwareLogger(TagStateRouter.class);
     private static final String RULE_SUFFIX = ".tag-router";
+    public static final char TAG_SEPERATOR = '|';
 
     private volatile TagRouterRule tagRouterRule;
     private String application;
@@ -106,7 +108,8 @@ public BitList<Invoker<T>> doRoute(BitList<Invoker<T>> invokers, URL url, Invoca
 
         // if we are requesting for a Provider with a specific tag
         if (StringUtils.isNotEmpty(tag)) {
-            Set<String> addresses = tagRouterRuleCopy.getTagnameToAddresses().get(tag);
+            Map<String, Set<String>> tagnameToAddresses = tagRouterRuleCopy.getTagnameToAddresses();
+            Set<String> addresses = selectAddressByTagLevel(tagnameToAddresses, tag, isForceUseTag(invocation));
             // filter by dynamic tag group first
             if (addresses != null) { // null means tag not set
                 result = filterInvoker(invokers, invoker -> addressMatches(invoker.getUrl(), addresses));
@@ -306,4 +309,34 @@ public void stop() {
     public void setTagRouterRule(TagRouterRule tagRouterRule) {
         this.tagRouterRule = tagRouterRule;
     }
+
+    /**
+     * select addresses by tag with level
+     * <p>
+     * example:
+     * selector=beta|team1|partner1
+     * step1.select tagAddresses with selector=beta|team1|partner1, if result is empty, then run step2
+     * step2.select tagAddresses with selector=beta|team1, if result is empty, then run step3
+     * step3.select tagAddresses with selector=beta, if result is empty, result is null
+     * </p>
+     *
+     * @param tagAddresses
+     * @param tagSelector  eg: beta|team1|partner1
+     * @return
+     */
+    public static Set<String> selectAddressByTagLevel(Map<String, Set<String>> tagAddresses, String tagSelector, boolean isForce) {
+        if (isForce || StringUtils.isNotContains(tagSelector, TAG_SEPERATOR)) {
+            return tagAddresses.get(tagSelector);
+        }
+        String[] selectors = StringUtils.split(tagSelector, TAG_SEPERATOR);
+        for (int i = selectors.length; i > 0; i--) {
+            String selectorTmp = StringUtils.join(selectors, TAG_SEPERATOR, 0, i);
+            Set<String> addresses = tagAddresses.get(selectorTmp);
+            if (CollectionUtils.isNotEmpty(addresses)) {
+                return addresses;
+            }
+        }
+        return null;
+    }
+
 }

dubbo-plugin/dubbo-plugin-router-tag/src/test/java/org/apache/dubbo/rpc/cluster/router/tag/TagStateRouterTest.java

@@ -24,21 +24,24 @@
 import org.apache.dubbo.rpc.Invoker;
 import org.apache.dubbo.rpc.RpcInvocation;
 import org.apache.dubbo.rpc.cluster.router.MockInvoker;
-//import org.apache.dubbo.rpc.cluster.router.mesh.util.TracingContextProvider;
 import org.apache.dubbo.rpc.cluster.router.state.BitList;
 import org.apache.dubbo.rpc.cluster.router.state.StateRouter;
 import org.apache.dubbo.rpc.cluster.router.tag.model.TagRouterRule;
 import org.apache.dubbo.rpc.cluster.router.tag.model.TagRuleParser;
 import org.apache.dubbo.rpc.model.ApplicationModel;
 import org.apache.dubbo.rpc.model.ModuleModel;
 
+import com.google.common.collect.Sets;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
+import java.util.Set;
 
 import static org.apache.dubbo.common.constants.CommonConstants.TAG_KEY;
 import static org.mockito.Mockito.when;
@@ -256,4 +259,47 @@ private TagRouterRule getTagRule() {
         TagRouterRule tagRouterRule = TagRuleParser.parse(tagRouterRuleConfig);
         return tagRouterRule;
     }
+
+    @Test
+    public void tagMultiLevelTest() {
+        String tagSelector = "beta|team1|partner1";
+        Set<String> address1 = Sets.newHashSet("192.168.5.1:20880");
+        Map<String, Set<String>> tagAddresses = new HashMap<>();
+        tagAddresses.put("beta", address1);
+        Assertions.assertEquals(address1, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+
+        Set<String> address2 = Sets.newHashSet("192.168.5.2:20880");
+        tagAddresses.put("beta|team1", address2);
+        Assertions.assertEquals(address2, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+
+        Set<String> address3 = Sets.newHashSet("192.168.5.3:20880");
+        tagAddresses.put("beta|team1|partner1", address3);
+        Assertions.assertEquals(address3, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+
+        tagSelector = "beta";
+        Assertions.assertEquals(address1, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+        tagSelector = "beta|team1";
+        Assertions.assertEquals(address2, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+        tagSelector = "beta|team1|partner1";
+        Assertions.assertEquals(address3, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+
+        tagSelector = "beta2";
+        Assertions.assertNull(TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+        tagSelector = "beta|team2";
+        Assertions.assertEquals(address1, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+        tagSelector = "beta|team1|partner2";
+        Assertions.assertEquals(address2, TagStateRouter.selectAddressByTagLevel(tagAddresses, tagSelector, false));
+
+
+    }
+
+    @Test
+    public void tagLevelForceTest() {
+        Set<String> addresses = Sets.newHashSet("192.168.1.223:20880");
+        Map<String, Set<String>> tagAddresses = new HashMap<>();
+        tagAddresses.put("beta", addresses);
+        Set<String> selectedAddresses = TagStateRouter.selectAddressByTagLevel(tagAddresses, "beta", true);
+        Assertions.assertEquals(addresses, selectedAddresses);
+    }
+
 }