[Dubbo - 2.6.x TagRouter Feature] Import old TagRouter into 2.6.x

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/Router.java

@@ -31,7 +31,7 @@
  * @see com.alibaba.dubbo.rpc.cluster.Cluster#join(Directory)
  * @see com.alibaba.dubbo.rpc.cluster.Directory#list(Invocation)
  */
-public interface Router extends Comparable<Router> {
+public interface Router extends Comparable<Router>{
 
     /**
      * get the router url.
@@ -51,4 +51,11 @@ public interface Router extends Comparable<Router> {
      */
     <T> List<Invoker<T>> route(List<Invoker<T>> invokers, URL url, Invocation invocation) throws RpcException;
 
+    /**
+     * Router's priority, used to sort routers.
+     *
+     * @return router's priority
+     */
+    int getPriority();
+
 }

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/directory/AbstractDirectory.java

@@ -28,6 +28,7 @@
 import com.alibaba.dubbo.rpc.cluster.Router;
 import com.alibaba.dubbo.rpc.cluster.RouterFactory;
 import com.alibaba.dubbo.rpc.cluster.router.MockInvokersSelector;
+import com.alibaba.dubbo.rpc.cluster.router.tag.TagRouter;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -107,6 +108,7 @@ protected void setRouters(List<Router> routers) {
         }
         // append mock invoker selector
         routers.add(new MockInvokersSelector());
+        routers.add(new TagRouter());
         Collections.sort(routers);
         this.routers = routers;
     }

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/router/AbstractRouter.java

@@ -0,0 +1,40 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 com.alibaba.dubbo.rpc.cluster.router;
+
+import com.alibaba.dubbo.common.URL;
+import com.alibaba.dubbo.rpc.cluster.Router;
+
+public abstract class AbstractRouter implements Router {
+
+    protected URL url;
+    protected int priority;
+
+    @Override
+    public URL getUrl() {
+        return url;
+    }
+
+    @Override
+    public int compareTo(Router o) {
+        return (this.getPriority() < o.getPriority()) ? -1 : ((this.getPriority() == o.getPriority()) ? 0 : 1);
+    }
+
+    public int getPriority() {
+        return priority;
+    }
+}

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/router/MockInvokersSelector.java

@@ -21,17 +21,21 @@
 import com.alibaba.dubbo.rpc.Invocation;
 import com.alibaba.dubbo.rpc.Invoker;
 import com.alibaba.dubbo.rpc.RpcException;
-import com.alibaba.dubbo.rpc.cluster.Router;
 
 import java.util.ArrayList;
 import java.util.List;
 
 /**
  * A specific Router designed to realize mock feature.
  * If a request is configured to use mock, then this router guarantees that only the invokers with protocol MOCK appear in final the invoker list, all other invokers will be excluded.
- *
  */
-public class MockInvokersSelector implements Router {
+public class MockInvokersSelector extends AbstractRouter {
+
+    private static final int DEFAULT_PRIORITY = Integer.MAX_VALUE;
+
+    public MockInvokersSelector() {
+        this.priority = DEFAULT_PRIORITY;
+    }
 
     @Override
     public <T> List<Invoker<T>> route(final List<Invoker<T>> invokers,
@@ -87,14 +91,4 @@ private <T> boolean hasMockProviders(final List<Invoker<T>> invokers) {
         return hasMockProvider;
     }
 
-    @Override
-    public URL getUrl() {
-        return null;
-    }
-
-    @Override
-    public int compareTo(Router o) {
-        return 1;
-    }
-
 }

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/router/condition/ConditionRouter.java

@@ -27,6 +27,7 @@
 import com.alibaba.dubbo.rpc.Invoker;
 import com.alibaba.dubbo.rpc.RpcException;
 import com.alibaba.dubbo.rpc.cluster.Router;
+import com.alibaba.dubbo.rpc.cluster.router.AbstractRouter;
 
 import java.text.ParseException;
 import java.util.ArrayList;
@@ -40,21 +41,19 @@
 
 /**
  * ConditionRouter
- *
  */
-public class ConditionRouter implements Router, Comparable<Router> {
+public class ConditionRouter extends AbstractRouter {
 
     private static final Logger logger = LoggerFactory.getLogger(ConditionRouter.class);
+    private static final int DEFAULT_PRIORITY = 2;
     private static Pattern ROUTE_PATTERN = Pattern.compile("([&!=,]*)\\s*([^&!=,\\s]+)");
-    private final URL url;
-    private final int priority;
     private final boolean force;
     private final Map<String, MatchPair> whenCondition;
     private final Map<String, MatchPair> thenCondition;
 
     public ConditionRouter(URL url) {
         this.url = url;
-        this.priority = url.getParameter(Constants.PRIORITY_KEY, 0);
+        this.priority = url.getParameter(Constants.PRIORITY_KEY, DEFAULT_PRIORITY);
         this.force = url.getParameter(Constants.FORCE_KEY, false);
         try {
             String rule = url.getParameterAndDecoded(Constants.RULE_KEY);

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/router/script/ScriptRouter.java

@@ -24,7 +24,7 @@
 import com.alibaba.dubbo.rpc.Invoker;
 import com.alibaba.dubbo.rpc.RpcContext;
 import com.alibaba.dubbo.rpc.RpcException;
-import com.alibaba.dubbo.rpc.cluster.Router;
+import com.alibaba.dubbo.rpc.cluster.router.AbstractRouter;
 
 import javax.script.Bindings;
 import javax.script.Compilable;
@@ -40,26 +40,23 @@
 
 /**
  * ScriptRouter
- *
  */
-public class ScriptRouter implements Router {
+public class ScriptRouter extends AbstractRouter {
 
     private static final Logger logger = LoggerFactory.getLogger(ScriptRouter.class);
 
+    private static final int DEFAULT_PRIORITY = 1;
+
     private static final Map<String, ScriptEngine> engines = new ConcurrentHashMap<String, ScriptEngine>();
 
     private final ScriptEngine engine;
 
-    private final int priority;
-
     private final String rule;
 
-    private final URL url;
-
     public ScriptRouter(URL url) {
         this.url = url;
         String type = url.getParameter(Constants.TYPE_KEY);
-        this.priority = url.getParameter(Constants.PRIORITY_KEY, 0);
+        this.priority = url.getParameter(Constants.PRIORITY_KEY, DEFAULT_PRIORITY);
         String rule = url.getParameterAndDecoded(Constants.RULE_KEY);
         if (type == null || type.length() == 0) {
             type = Constants.DEFAULT_SCRIPT_TYPE_KEY;
@@ -79,11 +76,6 @@ public ScriptRouter(URL url) {
         this.rule = rule;
     }
 
-    @Override
-    public URL getUrl() {
-        return url;
-    }
-
     @Override
     @SuppressWarnings("unchecked")
     public <T> List<Invoker<T>> route(List<Invoker<T>> invokers, URL url, Invocation invocation) throws RpcException {
@@ -114,13 +106,4 @@ public <T> List<Invoker<T>> route(List<Invoker<T>> invokers, URL url, Invocation
         }
     }
 
-    @Override
-    public int compareTo(Router o) {
-        if (o == null || o.getClass() != ScriptRouter.class) {
-            return 1;
-        }
-        ScriptRouter c = (ScriptRouter) o;
-        return this.priority == c.priority ? rule.compareTo(c.rule) : (this.priority > c.priority ? 1 : -1);
-    }
-
 }

dubbo-cluster/src/main/java/com/alibaba/dubbo/rpc/cluster/router/tag/TagRouter.java

@@ -0,0 +1,79 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 com.alibaba.dubbo.rpc.cluster.router.tag;
+
+import com.alibaba.dubbo.common.Constants;
+import com.alibaba.dubbo.common.URL;
+import com.alibaba.dubbo.common.utils.StringUtils;
+import com.alibaba.dubbo.rpc.Invocation;
+import com.alibaba.dubbo.rpc.Invoker;
+import com.alibaba.dubbo.rpc.RpcContext;
+import com.alibaba.dubbo.rpc.RpcException;
+import com.alibaba.dubbo.rpc.cluster.router.AbstractRouter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * TagRouter
+ */
+public class TagRouter extends AbstractRouter {
+
+    private static final int DEFAULT_PRIORITY = 100;
+    private static final URL ROUTER_URL = new URL("tag", Constants.ANYHOST_VALUE, 0, Constants.ANY_VALUE).addParameters(Constants.RUNTIME_KEY, "true");
+
+    public TagRouter() {
+        this.url = ROUTER_URL;
+        this.priority = url.getParameter(Constants.PRIORITY_KEY, DEFAULT_PRIORITY);
+    }
+
+    @Override
+    public URL getUrl() {
+        return url;
+    }
+
+    @Override
+    public <T> List<Invoker<T>> route(List<Invoker<T>> invokers, URL url, Invocation invocation) throws RpcException {
+        // filter
+        List<Invoker<T>> result = new ArrayList<Invoker<T>>();
+        // Dynamic param
+        String tag = RpcContext.getContext().getAttachment(Constants.TAG_KEY);
+        // Tag request
+        if (!StringUtils.isEmpty(tag)) {
+            // Select tag invokers first
+            for (Invoker<T> invoker : invokers) {
+                if (tag.equals(invoker.getUrl().getParameter(Constants.TAG_KEY))) {
+                    result.add(invoker);
+                }
+            }
+        }
+        // If Constants.REQUEST_TAG_KEY unspecified or no invoker be selected, downgrade to normal invokers
+        if (result.isEmpty()) {
+            // Only forceTag = true force match, otherwise downgrade
+            String forceTag = RpcContext.getContext().getAttachment(Constants.FORCE_USE_TAG);
+            if (StringUtils.isEmpty(forceTag) || "false".equals(forceTag)) {
+                for (Invoker<T> invoker : invokers) {
+                    if (StringUtils.isEmpty(invoker.getUrl().getParameter(Constants.TAG_KEY))) {
+                        result.add(invoker);
+                    }
+                }
+            }
+        }
+        return result;
+    }
+
+}

dubbo-cluster/src/test/java/com/alibaba/dubbo/rpc/cluster/loadbalance/LoadBalanceTest.java

@@ -123,7 +123,7 @@ private AbstractLoadBalance getLoadBalance(String loadbalanceName) {
 
     @Test
     public void testRoundRobinLoadBalance_select() {
-        int runs = 10000;
+        int runs = 1000;
         Map<Invoker, AtomicLong> counter = getInvokeCounter(runs, RoundRobinLoadBalance.NAME);
         for (Invoker minvoker : counter.keySet()) {
             Long count = counter.get(minvoker).get();
@@ -146,7 +146,7 @@ private void assertStrictWRRResult(int runs, Map<Invoker, InvokeResult> resultMa
     public void testRoundRobinLoadBalanceWithWeight() {
         final Map<Invoker, InvokeResult> totalMap = new HashMap<Invoker, InvokeResult>();
         final AtomicBoolean shouldBegin = new AtomicBoolean(false);
-        final int runs = 10000;
+        final int runs = 1000;
         List<Thread> threads = new ArrayList<Thread>();
         int threadNum = 10;
         for (int i = 0; i < threadNum; i ++) {
@@ -188,7 +188,7 @@ public void run() {
 
     @Test
     public void testRoundRobinLoadBalanceWithWeightShouldNotRecycle() {
-        int runs = 10000;
+        int runs = 1000;
         //tmperately add a new invoker
         weightInvokers.add(weightInvokerTmp);
         try {
@@ -226,7 +226,7 @@ public void testRoundRobinLoadBalanceWithWeightShouldRecycle() {
                 Assert.assertTrue("getField failed", true);
             }
         }
-        int runs = 10000;
+        int runs = 1000;
         //temporarily add a new invoker
         weightInvokers.add(weightInvokerTmp);
         try {
@@ -249,7 +249,7 @@ public void testRoundRobinLoadBalanceWithWeightShouldRecycle() {
     public void testSelectByWeightLeastActive() {
         int sumInvoker1 = 0;
         int sumInvoker2 = 0;
-        int loop = 10000;
+        int loop = 1000;
         LeastActiveLoadBalance lb = new LeastActiveLoadBalance();
         for (int i = 0; i < loop; i++) {
             Invoker selected = lb.select(weightInvokers, null, weightTestInvocation);
@@ -273,7 +273,7 @@ public void testSelectByWeightRandom() {
         int sumInvoker1 = 0;
         int sumInvoker2 = 0;
         int sumInvoker3 = 0;
-        int loop = 10000;
+        int loop = 1000;
         RandomLoadBalance lb = new RandomLoadBalance();
         for (int i = 0; i < loop; i++) {
             Invoker selected = lb.select(weightInvokers, null, weightTestInvocation);
@@ -323,7 +323,7 @@ public void testRandomLoadBalance_select() {
 
     @Test
     public void testLeastActiveLoadBalance_select() {
-        int runs = 10000;
+        int runs = 1000;
         Map<Invoker, AtomicLong> counter = getInvokeCounter(runs, LeastActiveLoadBalance.NAME);
         for (Invoker minvoker : counter.keySet()) {
             Long count = counter.get(minvoker).get();