Add adapter module for Apache Dubbo 2.7.x and above

- copied legacy code and adapts to new package
- also update document for legacy Dubbo adapter

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-adapter/pom.xml

@@ -17,6 +17,7 @@
     <modules>
         <module>sentinel-web-servlet</module>
         <module>sentinel-dubbo-adapter</module>
+        <module>sentinel-apache-dubbo-adapter</module>
         <module>sentinel-grpc-adapter</module>
         <module>sentinel-zuul-adapter</module>
         <module>sentinel-reactor-adapter</module>

sentinel-adapter/sentinel-apache-dubbo-adapter/README.md

@@ -0,0 +1,68 @@
+# Sentinel Apache Dubbo Adapter
+
+> Note: 中文文档请见[此处](https://github.com/alibaba/Sentinel/wiki/主流框架的适配#dubbo)。
+
+Sentinel Dubbo Adapter provides service consumer filter and provider filter
+for [Apache Dubbo](https://dubbo.apache.org/en-us/) services.
+
+**Note: This adapter only supports Apache Dubbo 2.7.x and above.** For legacy `com.alibaba:dubbo` 2.6.x,
+please use `sentinel-dubbo-adapter` module instead.
+
+To use Sentinel Dubbo Adapter, you can simply add the following dependency to your `pom.xml`:
+
+```xml
+<dependency>
+    <groupId>com.alibaba.csp</groupId>
+    <artifactId>sentinel-apache-dubbo-adapter</artifactId>
+    <version>x.y.z</version>
+</dependency>
+```
+
+The Sentinel filters are **enabled by default**. Once you add the dependency,
+the Dubbo services and methods will become protected resources in Sentinel,
+which can leverage Sentinel's flow control and guard ability when rules are configured.
+Demos can be found in [sentinel-demo-dubbo](https://github.com/alibaba/Sentinel/tree/master/sentinel-demo/sentinel-demo-dubbo).
+
+If you don't want the filters enabled, you can manually disable them. For example:
+
+```xml
+<dubbo:consumer filter="-sentinel.dubbo.consumer.filter"/>
+
+<dubbo:provider filter="-sentinel.dubbo.provider.filter"/>
+```
+
+For more details of Dubbo filter, see [here](http://dubbo.apache.org/en-us/docs/dev/impls/filter.html).
+
+## Dubbo resources
+
+The resource for Dubbo services has two granularities: service interface and service method.
+
+- Service interface：resourceName format is `interfaceName`，e.g. `com.alibaba.csp.sentinel.demo.dubbo.FooService`
+- Service method：resourceName format is `interfaceName:methodSignature`，e.g. `com.alibaba.csp.sentinel.demo.dubbo.FooService:sayHello(java.lang.String)`
+
+## Flow control based on caller
+
+In many circumstances, it's also significant to control traffic flow based on the **caller**.
+For example, assuming that there are two services A and B, both of them initiate remote call requests to the service provider.
+If we want to limit the calls from service B only, we can set the `limitApp` of flow rule as the identifier of service B (e.g. service name).
+
+Sentinel Dubbo Adapter will automatically resolve the Dubbo consumer's *application name* as the caller's name (`origin`),
+and will bring the caller's name when doing resource protection.
+If `limitApp` of flow rules is not configured (`default`), flow control will take effects on all callers.
+If `limitApp` of a flow rule is configured with a caller, then the corresponding flow rule will only take effect on the specific caller.
+
+> Note: Dubbo consumer does not provide its Dubbo application name when doing RPC,
+so developers should manually put the application name into *attachment* at consumer side,
+then extract it at provider side. Sentinel Dubbo Adapter has implemented a filter (`DubboAppContextFilter`)
+where consumer can carry application name information to provider automatically.
+If the consumer does not use Sentinel Dubbo Adapter but requires flow control based on caller, developers can manually put the application name into attachment with the key `dubboApplication`.
+
+## Global fallback
+
+Sentinel Dubbo Adapter supports global fallback configuration.
+The global fallback will handle exceptions and give replacement result when blocked by
+flow control, degrade or system load protection. You can implement your own `DubboFallback` interface
+and then register to `DubboFallbackRegistry`. If no fallback is configured, Sentinel will wrap the `BlockException`
+then directly throw it out.
+
+Besides, we can also leverage [Dubbo mock mechanism](http://dubbo.apache.org/en-us/docs/user/demos/local-mock.html) to provide fallback implementation of degraded Dubbo services.

sentinel-adapter/sentinel-apache-dubbo-adapter/pom.xml

@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>sentinel-adapter</artifactId>
+        <groupId>com.alibaba.csp</groupId>
+        <version>1.5.1-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>sentinel-apache-dubbo-adapter</artifactId>
+    <packaging>jar</packaging>
+
+    <properties>
+        <java.source.version>1.8</java.source.version>
+        <java.target.version>1.8</java.target.version>
+        <apache.dubbo.version>2.7.1</apache.dubbo.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.dubbo</groupId>
+            <artifactId>dubbo</artifactId>
+            <version>${apache.dubbo.version}</version>
+            <scope>provided</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.alibaba</groupId>
+            <artifactId>fastjson</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/DubboAppContextFilter.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.extension.Activate;
+import org.apache.dubbo.rpc.Filter;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcContext;
+import org.apache.dubbo.rpc.RpcException;
+
+/**
+ * Puts current consumer's application name in the attachment of each invocation.
+ *
+ * @author Eric Zhao
+ */
+@Activate(group = "consumer")
+public class DubboAppContextFilter implements Filter {
+
+    @Override
+    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
+        String application = invoker.getUrl().getParameter(Constants.APPLICATION_KEY);
+        if (application != null) {
+            RpcContext.getContext().setAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY, application);
+        }
+        return invoker.invoke(invocation);
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/DubboUtils.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+
+/**
+ * @author Eric Zhao
+ */
+public final class DubboUtils {
+
+    public static final String SENTINEL_DUBBO_APPLICATION_KEY = "dubboApplication";
+
+    public static String getApplication(Invocation invocation, String defaultValue) {
+        if (invocation == null || invocation.getAttachments() == null) {
+            throw new IllegalArgumentException("Bad invocation instance");
+        }
+        return invocation.getAttachment(SENTINEL_DUBBO_APPLICATION_KEY, defaultValue);
+    }
+
+    public static String getResourceName(Invoker<?> invoker, Invocation invocation) {
+        StringBuilder buf = new StringBuilder(64);
+        buf.append(invoker.getInterface().getName())
+            .append(":")
+            .append(invocation.getMethodName())
+            .append("(");
+        boolean isFirst = true;
+        for (Class<?> clazz : invocation.getParameterTypes()) {
+            if (!isFirst) {
+                buf.append(",");
+            }
+            buf.append(clazz.getName());
+            isFirst = false;
+        }
+        buf.append(")");
+        return buf.toString();
+    }
+
+    private DubboUtils() {}
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/SentinelDubboConsumerFilter.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.SphU;
+import com.alibaba.csp.sentinel.Tracer;
+import com.alibaba.csp.sentinel.log.RecordLog;
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+
+import com.alibaba.csp.sentinel.adapter.dubbo.fallback.DubboFallbackRegistry;
+import org.apache.dubbo.common.extension.Activate;
+import org.apache.dubbo.rpc.Filter;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcException;
+
+/**
+ * <p>Dubbo service consumer filter for Sentinel. Auto activated by default.</p>
+ *
+ * If you want to disable the consumer filter, you can configure:
+ * <pre>
+ * &lt;dubbo:consumer filter="-sentinel.dubbo.consumer.filter"/&gt;
+ * </pre>
+ *
+ * @author Carpenter Lee
+ * @author Eric Zhao
+ */
+@Activate(group = "consumer")
+public class SentinelDubboConsumerFilter implements Filter {
+
+    public SentinelDubboConsumerFilter() {
+        RecordLog.info("Sentinel Apache Dubbo consumer filter initialized");
+    }
+
+    @Override
+    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
+        Entry interfaceEntry = null;
+        Entry methodEntry = null;
+        try {
+            String resourceName = DubboUtils.getResourceName(invoker, invocation);
+            interfaceEntry = SphU.entry(invoker.getInterface().getName(), EntryType.OUT);
+            methodEntry = SphU.entry(resourceName, EntryType.OUT);
+
+            Result result = invoker.invoke(invocation);
+            if (result.hasException()) {
+                Throwable e = result.getException();
+                // Record common exception.
+                Tracer.traceEntry(e, interfaceEntry);
+                Tracer.traceEntry(e, methodEntry);
+            }
+            return result;
+        } catch (BlockException e) {
+            return DubboFallbackRegistry.getConsumerFallback().handle(invoker, invocation, e);
+        } catch (RpcException e) {
+            Tracer.traceEntry(e, interfaceEntry);
+            Tracer.traceEntry(e, methodEntry);
+            throw e;
+        } finally {
+            if (methodEntry != null) {
+                methodEntry.exit();
+            }
+            if (interfaceEntry != null) {
+                interfaceEntry.exit();
+            }
+        }
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/SentinelDubboProviderFilter.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.SphU;
+import com.alibaba.csp.sentinel.Tracer;
+import com.alibaba.csp.sentinel.adapter.dubbo.fallback.DubboFallbackRegistry;
+import com.alibaba.csp.sentinel.context.ContextUtil;
+import com.alibaba.csp.sentinel.log.RecordLog;
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+
+import org.apache.dubbo.common.extension.Activate;
+import org.apache.dubbo.rpc.Filter;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcException;
+
+/**
+ * <p>Apache Dubbo service provider filter that enables integration with Sentinel. Auto activated by default.</p>
+ * <p>Note: this only works for Apache Dubbo 2.7.x or above version.</p>
+ *
+ * If you want to disable the provider filter, you can configure:
+ * <pre>
+ * &lt;dubbo:provider filter="-sentinel.dubbo.provider.filter"/&gt;
+ * </pre>
+ *
+ * @author Carpenter Lee
+ * @author Eric Zhao
+ */
+@Activate(group = "provider")
+public class SentinelDubboProviderFilter implements Filter {
+
+    public SentinelDubboProviderFilter() {
+        RecordLog.info("Sentinel Apache Dubbo provider filter initialized");
+    }
+
+    @Override
+    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
+        // Get origin caller.
+        String application = DubboUtils.getApplication(invocation, "");
+
+        Entry interfaceEntry = null;
+        Entry methodEntry = null;
+        try {
+            String resourceName = DubboUtils.getResourceName(invoker, invocation);
+            String interfaceName = invoker.getInterface().getName();
+            // Only need to create entrance context at provider side, as context will take effect
+            // at entrance of invocation chain only (for inbound traffic).
+            ContextUtil.enter(resourceName, application);
+            interfaceEntry = SphU.entry(interfaceName, EntryType.IN);
+            methodEntry = SphU.entry(resourceName, EntryType.IN, 1, invocation.getArguments());
+
+            Result result = invoker.invoke(invocation);
+            if (result.hasException()) {
+                Throwable e = result.getException();
+                // Record common exception.
+                Tracer.traceEntry(e, interfaceEntry);
+                Tracer.traceEntry(e, methodEntry);
+            }
+            return result;
+        } catch (BlockException e) {
+            return DubboFallbackRegistry.getProviderFallback().handle(invoker, invocation, e);
+        } catch (RpcException e) {
+            Tracer.traceEntry(e, interfaceEntry);
+            Tracer.traceEntry(e, methodEntry);
+            throw e;
+        } finally {
+            if (methodEntry != null) {
+                methodEntry.exit(1, invocation.getArguments());
+            }
+            if (interfaceEntry != null) {
+                interfaceEntry.exit();
+            }
+            ContextUtil.exit();
+        }
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/fallback/DefaultDubboFallback.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.fallback;
+
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+import com.alibaba.csp.sentinel.slots.block.SentinelRpcException;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+
+/**
+ * @author Eric Zhao
+ */
+public class DefaultDubboFallback implements DubboFallback {
+
+    @Override
+    public Result handle(Invoker<?> invoker, Invocation invocation, BlockException ex) {
+        // Just wrap and throw the exception.
+        throw new SentinelRpcException(ex);
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/fallback/DubboFallback.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.fallback;
+
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+
+/**
+ * Fallback handler for Dubbo services.
+ *
+ * @author Eric Zhao
+ */
+@FunctionalInterface
+public interface DubboFallback {
+
+    /**
+     * Handle the block exception and provide fallback result.
+     *
+     * @param invoker Dubbo invoker
+     * @param invocation Dubbo invocation
+     * @param ex block exception
+     * @return fallback result
+     */
+    Result handle(Invoker<?> invoker, Invocation invocation, BlockException ex);
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/dubbo/fallback/DubboFallbackRegistry.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.fallback;
+
+import com.alibaba.csp.sentinel.util.AssertUtil;
+
+/**
+ * <p>Global fallback registry for Dubbo.</p>
+ *
+ * <p>
+ * Note: Circuit breaking is mainly designed for consumer. The provider should not
+ * give fallback result in most circumstances.
+ * </p>
+ *
+ * @author Eric Zhao
+ */
+public final class DubboFallbackRegistry {
+
+    private static volatile DubboFallback consumerFallback = new DefaultDubboFallback();
+    private static volatile DubboFallback providerFallback = new DefaultDubboFallback();
+
+    public static DubboFallback getConsumerFallback() {
+        return consumerFallback;
+    }
+
+    public static void setConsumerFallback(DubboFallback consumerFallback) {
+        AssertUtil.notNull(consumerFallback, "consumerFallback cannot be null");
+        DubboFallbackRegistry.consumerFallback = consumerFallback;
+    }
+
+    public static DubboFallback getProviderFallback() {
+        return providerFallback;
+    }
+
+    public static void setProviderFallback(DubboFallback providerFallback) {
+        AssertUtil.notNull(providerFallback, "providerFallback cannot be null");
+        DubboFallbackRegistry.providerFallback = providerFallback;
+    }
+
+    private DubboFallbackRegistry() {}
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/main/resources/META-INF/dubbo/org.apache.dubbo.rpc.Filter

@@ -0,0 +1,3 @@
+sentinel.dubbo.provider.filter=com.alibaba.csp.sentinel.adapter.dubbo.SentinelDubboProviderFilter
+sentinel.dubbo.consumer.filter=com.alibaba.csp.sentinel.adapter.dubbo.SentinelDubboConsumerFilter
+dubbo.application.context.name.filter=com.alibaba.csp.sentinel.adapter.dubbo.DubboAppContextFilter

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/BaseTest.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel;
+
+import com.alibaba.csp.sentinel.slots.clusterbuilder.ClusterBuilderSlot;
+
+import org.apache.dubbo.rpc.RpcContext;
+
+/**
+ * Base test class, provide common methods for subClass
+ * The package is same as CtSph, to call CtSph.resetChainMap() method for test
+ *
+ * Note: Only for test. DO NOT USE IN PRODUCTION!
+ *
+ * @author cdfive
+ */
+public class BaseTest {
+
+    /**
+     * Clean up resources for context, clusterNodeMap, processorSlotChainMap
+     */
+    protected static void cleanUpAll() {
+        RpcContext.removeContext();
+        ClusterBuilderSlot.getClusterNodeMap().clear();
+        CtSph.resetChainMap();
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/DubboAppContextFilterTest.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import com.alibaba.csp.sentinel.BaseTest;
+
+import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.RpcContext;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
+/**
+ * @author cdfive
+ */
+public class DubboAppContextFilterTest extends BaseTest {
+
+    private DubboAppContextFilter filter = new DubboAppContextFilter();
+
+    @Before
+    public void setUp() {
+        cleanUpAll();
+    }
+
+    @After
+    public void cleanUp() {
+        cleanUpAll();
+    }
+
+    @Test
+    public void testInvokeApplicationKey() {
+        Invoker invoker = mock(Invoker.class);
+        Invocation invocation = mock(Invocation.class);
+        URL url = URL.valueOf("test://test:111/test?application=serviceA");
+        when(invoker.getUrl()).thenReturn(url);
+
+        filter.invoke(invoker, invocation);
+        verify(invoker).invoke(invocation);
+
+        String application = RpcContext.getContext().getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY);
+        assertEquals("serviceA", application);
+    }
+
+    @Test
+    public void testInvokeNullApplicationKey() {
+        Invoker invoker = mock(Invoker.class);
+        Invocation invocation = mock(Invocation.class);
+        URL url = URL.valueOf("test://test:111/test?application=");
+        when(invoker.getUrl()).thenReturn(url);
+
+        filter.invoke(invoker, invocation);
+        verify(invoker).invoke(invocation);
+
+        String application = RpcContext.getContext().getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY);
+        assertNull(application);
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/DubboUtilsTest.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+import java.util.HashMap;
+
+import com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+import static org.mockito.Mockito.*;
+
+/**
+ * @author cdfive
+ */
+public class DubboUtilsTest {
+
+    @Test
+    public void testGetApplication() {
+        Invocation invocation = mock(Invocation.class);
+        when(invocation.getAttachments()).thenReturn(new HashMap<>());
+        when(invocation.getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY, ""))
+            .thenReturn("consumerA");
+
+        String application = DubboUtils.getApplication(invocation, "");
+        verify(invocation).getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY, "");
+
+        assertEquals("consumerA", application);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testGetApplicationNoAttachments() {
+        Invocation invocation = mock(Invocation.class);
+        when(invocation.getAttachments()).thenReturn(null);
+        when(invocation.getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY, ""))
+            .thenReturn("consumerA");
+
+        DubboUtils.getApplication(invocation, "");
+
+        fail("No attachments in invocation, IllegalArgumentException should be thrown!");
+    }
+
+    @Test
+    public void testGetResourceName() {
+        Invoker invoker = mock(Invoker.class);
+        when(invoker.getInterface()).thenReturn(DemoService.class);
+
+        Invocation invocation = mock(Invocation.class);
+        Method method = DemoService.class.getMethods()[0];
+        when(invocation.getMethodName()).thenReturn(method.getName());
+        when(invocation.getParameterTypes()).thenReturn(method.getParameterTypes());
+
+        String resourceName = DubboUtils.getResourceName(invoker, invocation);
+
+        assertEquals("com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService:sayHello(java.lang.String,int)", resourceName);
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/SentinelDubboConsumerFilterTest.java

@@ -0,0 +1,142 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import com.alibaba.csp.sentinel.BaseTest;
+import com.alibaba.csp.sentinel.Constants;
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService;
+import com.alibaba.csp.sentinel.context.Context;
+import com.alibaba.csp.sentinel.context.ContextUtil;
+import com.alibaba.csp.sentinel.node.ClusterNode;
+import com.alibaba.csp.sentinel.node.DefaultNode;
+import com.alibaba.csp.sentinel.node.Node;
+import com.alibaba.csp.sentinel.node.StatisticNode;
+import com.alibaba.csp.sentinel.slotchain.ResourceWrapper;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.Set;
+
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
+/**
+ * @author cdfive
+ */
+public class SentinelDubboConsumerFilterTest extends BaseTest {
+
+    private SentinelDubboConsumerFilter filter = new SentinelDubboConsumerFilter();
+
+    @Before
+    public void setUp() {
+        cleanUpAll();
+    }
+
+    @After
+    public void cleanUp() {
+        cleanUpAll();
+    }
+
+    @Test
+    public void testInvoke() {
+        final Invoker invoker = mock(Invoker.class);
+        when(invoker.getInterface()).thenReturn(DemoService.class);
+
+        final Invocation invocation = mock(Invocation.class);
+        Method method = DemoService.class.getMethods()[0];
+        when(invocation.getMethodName()).thenReturn(method.getName());
+        when(invocation.getParameterTypes()).thenReturn(method.getParameterTypes());
+
+        final Result result = mock(Result.class);
+        when(result.hasException()).thenReturn(false);
+        when(invoker.invoke(invocation)).thenAnswer(invocationOnMock -> {
+            verifyInvocationStructure(invoker, invocation);
+            return result;
+        });
+
+        filter.invoke(invoker, invocation);
+        verify(invoker).invoke(invocation);
+
+        Context context = ContextUtil.getContext();
+        assertNull(context);
+    }
+
+    /**
+     * Simply verify invocation structure in memory:
+     * EntranceNode(defaultContextName)
+     * --InterfaceNode(interfaceName)
+     * ----MethodNode(resourceName)
+     */
+    private void verifyInvocationStructure(Invoker invoker, Invocation invocation) {
+        Context context = ContextUtil.getContext();
+        assertNotNull(context);
+
+        // As not call ContextUtil.enter(resourceName, application) in SentinelDubboConsumerFilter, use default context
+        // In actual project, a consumer is usually also a provider, the context will be created by SentinelDubboProviderFilter
+        // If consumer is on the top of Dubbo RPC invocation chain, use default context
+        String resourceName = DubboUtils.getResourceName(invoker, invocation);
+        assertEquals(Constants.CONTEXT_DEFAULT_NAME, context.getName());
+        assertEquals("", context.getOrigin());
+
+        DefaultNode entranceNode = context.getEntranceNode();
+        ResourceWrapper entranceResource = entranceNode.getId();
+        assertEquals(Constants.CONTEXT_DEFAULT_NAME, entranceResource.getName());
+        assertSame(EntryType.IN, entranceResource.getType());
+
+        // As SphU.entry(interfaceName, EntryType.OUT);
+        Set<Node> childList = entranceNode.getChildList();
+        assertEquals(1, childList.size());
+        DefaultNode interfaceNode = (DefaultNode) childList.iterator().next();
+        ResourceWrapper interfaceResource = interfaceNode.getId();
+        assertEquals(DemoService.class.getName(), interfaceResource.getName());
+        assertSame(EntryType.OUT, interfaceResource.getType());
+
+        // As SphU.entry(resourceName, EntryType.OUT);
+        childList = interfaceNode.getChildList();
+        assertEquals(1, childList.size());
+        DefaultNode methodNode = (DefaultNode) childList.iterator().next();
+        ResourceWrapper methodResource = methodNode.getId();
+        assertEquals(resourceName, methodResource.getName());
+        assertSame(EntryType.OUT, methodResource.getType());
+
+        // Verify curEntry
+        Entry curEntry = context.getCurEntry();
+        assertSame(methodNode, curEntry.getCurNode());
+        assertSame(interfaceNode, curEntry.getLastNode());
+        assertNull(curEntry.getOriginNode());// As context origin is not "", no originNode should be created in curEntry
+
+        // Verify clusterNode
+        ClusterNode methodClusterNode = methodNode.getClusterNode();
+        ClusterNode interfaceClusterNode = interfaceNode.getClusterNode();
+        assertNotSame(methodClusterNode, interfaceClusterNode);// Different resource->Different ProcessorSlot->Different ClusterNode
+
+        // As context origin is "", the StatisticNode should not be created in originCountMap of ClusterNode
+        Map<String, StatisticNode> methodOriginCountMap = methodClusterNode.getOriginCountMap();
+        assertEquals(0, methodOriginCountMap.size());
+
+        Map<String, StatisticNode> interfaceOriginCountMap = interfaceClusterNode.getOriginCountMap();
+        assertEquals(0, interfaceOriginCountMap.size());
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/SentinelDubboProviderFilterTest.java

@@ -0,0 +1,145 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo;
+
+import com.alibaba.csp.sentinel.BaseTest;
+import com.alibaba.csp.sentinel.Entry;
+import com.alibaba.csp.sentinel.EntryType;
+import com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService;
+import com.alibaba.csp.sentinel.context.Context;
+import com.alibaba.csp.sentinel.context.ContextUtil;
+import com.alibaba.csp.sentinel.node.ClusterNode;
+import com.alibaba.csp.sentinel.node.DefaultNode;
+import com.alibaba.csp.sentinel.node.Node;
+import com.alibaba.csp.sentinel.node.StatisticNode;
+import com.alibaba.csp.sentinel.slotchain.ResourceWrapper;
+
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.Set;
+
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
+/**
+ * @author cdfive
+ */
+public class SentinelDubboProviderFilterTest extends BaseTest {
+
+    private SentinelDubboProviderFilter filter = new SentinelDubboProviderFilter();
+
+    @Before
+    public void setUp() {
+        cleanUpAll();
+    }
+
+    @After
+    public void cleanUp() {
+        cleanUpAll();
+    }
+
+    @Test
+    public void testInvoke() {
+        final String originApplication = "consumerA";
+
+        final Invoker invoker = mock(Invoker.class);
+        when(invoker.getInterface()).thenReturn(DemoService.class);
+
+        final Invocation invocation = mock(Invocation.class);
+        Method method = DemoService.class.getMethods()[0];
+        when(invocation.getMethodName()).thenReturn(method.getName());
+        when(invocation.getParameterTypes()).thenReturn(method.getParameterTypes());
+        when(invocation.getAttachment(DubboUtils.SENTINEL_DUBBO_APPLICATION_KEY, ""))
+            .thenReturn(originApplication);
+
+        final Result result = mock(Result.class);
+        when(result.hasException()).thenReturn(false);
+        when(invoker.invoke(invocation)).thenAnswer(invocationOnMock -> {
+            verifyInvocationStructure(originApplication, invoker, invocation);
+            return result;
+        });
+
+        filter.invoke(invoker, invocation);
+        verify(invoker).invoke(invocation);
+
+        Context context = ContextUtil.getContext();
+        assertNull(context);
+    }
+
+    /**
+     * Simply verify invocation structure in memory:
+     * EntranceNode(resourceName)
+     * --InterfaceNode(interfaceName)
+     * ----MethodNode(resourceName)
+     */
+    private void verifyInvocationStructure(String originApplication, Invoker invoker, Invocation invocation) {
+        Context context = ContextUtil.getContext();
+        assertNotNull(context);
+
+        // As ContextUtil.enter(resourceName, application) in SentinelDubboProviderFilter
+        String resourceName = DubboUtils.getResourceName(invoker, invocation);
+        assertEquals(resourceName, context.getName());
+        assertEquals(originApplication, context.getOrigin());
+
+        DefaultNode entranceNode = context.getEntranceNode();
+        ResourceWrapper entranceResource = entranceNode.getId();
+        assertEquals(resourceName, entranceResource.getName());
+        assertSame(EntryType.IN, entranceResource.getType());
+
+        // As SphU.entry(interfaceName, EntryType.IN);
+        Set<Node> childList = entranceNode.getChildList();
+        assertEquals(1, childList.size());
+        DefaultNode interfaceNode = (DefaultNode) childList.iterator().next();
+        ResourceWrapper interfaceResource = interfaceNode.getId();
+        assertEquals(DemoService.class.getName(), interfaceResource.getName());
+        assertSame(EntryType.IN, interfaceResource.getType());
+
+        // As SphU.entry(resourceName, EntryType.IN, 1, invocation.getArguments());
+        childList = interfaceNode.getChildList();
+        assertEquals(1, childList.size());
+        DefaultNode methodNode = (DefaultNode) childList.iterator().next();
+        ResourceWrapper methodResource = methodNode.getId();
+        assertEquals(resourceName, methodResource.getName());
+        assertSame(EntryType.IN, methodResource.getType());
+
+        // Verify curEntry
+        Entry curEntry = context.getCurEntry();
+        assertSame(methodNode, curEntry.getCurNode());
+        assertSame(interfaceNode, curEntry.getLastNode());
+        assertNotNull(curEntry.getOriginNode());// As context origin is not "", originNode should be created
+
+        // Verify clusterNode
+        ClusterNode methodClusterNode = methodNode.getClusterNode();
+        ClusterNode interfaceClusterNode = interfaceNode.getClusterNode();
+        assertNotSame(methodClusterNode, interfaceClusterNode);// Different resource->Different ProcessorSlot->Different ClusterNode
+
+        // As context origin is not "", the StatisticNode should be created in originCountMap of ClusterNode
+        Map<String, StatisticNode> methodOriginCountMap = methodClusterNode.getOriginCountMap();
+        assertEquals(1, methodOriginCountMap.size());
+        assertTrue(methodOriginCountMap.containsKey(originApplication));
+
+        Map<String, StatisticNode> interfaceOriginCountMap = interfaceClusterNode.getOriginCountMap();
+        assertEquals(1, interfaceOriginCountMap.size());
+        assertTrue(interfaceOriginCountMap.containsKey(originApplication));
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/fallback/DubboFallbackRegistryTest.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.fallback;
+
+import com.alibaba.csp.sentinel.slots.block.BlockException;
+import com.alibaba.csp.sentinel.slots.block.SentinelRpcException;
+import com.alibaba.csp.sentinel.slots.block.flow.FlowException;
+
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcResult;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * @author Eric Zhao
+ */
+public class DubboFallbackRegistryTest {
+
+    @Test(expected = SentinelRpcException.class)
+    public void testDefaultFallback() {
+        // Test for default.
+        BlockException ex = new FlowException("xxx");
+        DubboFallbackRegistry.getConsumerFallback()
+            .handle(null, null, ex);
+    }
+
+    @Test
+    public void testCustomFallback() {
+        BlockException ex = new FlowException("xxx");
+        DubboFallbackRegistry.setConsumerFallback(
+            (invoker, invocation, e) -> new RpcResult("Error: " + e.getClass().getName()));
+        Result result = DubboFallbackRegistry.getConsumerFallback()
+            .handle(null, null, ex);
+        Assert.assertFalse("The invocation should not fail", result.hasException());
+        Assert.assertEquals("Error: " + ex.getClass().getName(), result.getValue());
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/provider/DemoService.java

@@ -0,0 +1,23 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.provider;
+
+/**
+ * @author leyou
+ */
+public interface DemoService {
+    String sayHello(String name, int n);
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/dubbo/provider/impl/DemoServiceImpl.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 1999-2018 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.dubbo.provider.impl;
+
+import com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService;
+
+/**
+ * @author leyou
+ */
+public class DemoServiceImpl implements DemoService {
+    public String sayHello(String name, int n) {
+        return "Hello " + name + ", " + n;
+    }
+}

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/resources/spring-dubbo-consumer-filter.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
+       xsi:schemaLocation="http://www.springframework.org/schema/beans
+       http://www.springframework.org/schema/beans/spring-beans.xsd
+       http://code.alibabatech.com/schema/dubbo
+       http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
+
+    <dubbo:application name="demo-consumer"/>
+    <dubbo:registry address="multicast://224.5.6.7:1234"/>
+    <dubbo:protocol name="dubbo" port="20880"/>
+    <dubbo:service interface="com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService" ref="demoServiceImp" />
+    <bean id="demoServiceImp" class="com.alibaba.csp.sentinel.adapter.dubbo.provider.impl.DemoServiceImpl"/>
+
+    <dubbo:reference id="demoService" interface="com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService"/>
+
+</beans>

sentinel-adapter/sentinel-apache-dubbo-adapter/src/test/resources/spring-dubbo-provider-filter.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
+       xsi:schemaLocation="http://www.springframework.org/schema/beans
+       http://www.springframework.org/schema/beans/spring-beans.xsd
+       http://code.alibabatech.com/schema/dubbo
+       http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
+
+    <dubbo:application name="demo-provider"/>
+    <dubbo:registry address="multicast://224.5.6.7:1234"/>
+    <dubbo:protocol name="dubbo" port="20880"/>
+    <dubbo:service interface="com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService" ref="demoServiceImp" />
+    <bean id="demoServiceImp" class="com.alibaba.csp.sentinel.adapter.dubbo.provider.impl.DemoServiceImpl"/>
+
+    <dubbo:reference id="demoService" interface="com.alibaba.csp.sentinel.adapter.dubbo.provider.DemoService"/>
+
+</beans>

sentinel-adapter/sentinel-dubbo-adapter/README.md

@@ -3,7 +3,10 @@
 > Note: 中文文档请见[此处](https://github.com/alibaba/Sentinel/wiki/%E4%B8%BB%E6%B5%81%E6%A1%86%E6%9E%B6%E7%9A%84%E9%80%82%E9%85%8D#dubbo)。
 
 Sentinel Dubbo Adapter provides service consumer filter and provider filter
-for [Dubbo](http://dubbo.io/) services.
+for [Dubbo](https://dubbo.apache.org/en-us/) services.
+
+**Note: This adapter only supports legacy Dubbo 2.6.x version and below.**
+For new Apache Dubbo 2.7.x or above version, please use `sentinel-apache-dubbo-adapter` module instead.
 
 To use Sentinel Dubbo Adapter, you can simply add the following dependency to your `pom.xml`:
 
@@ -28,7 +31,7 @@ If you don't want the filters enabled, you can manually disable them. For exampl
 <dubbo:provider filter="-sentinel.dubbo.provider.filter"/>
 ```
 
-For more details of Dubbo filter, see [here](https://dubbo.incubator.apache.org/#/docs/dev/impls/filter.md?lang=en-us).
+For more details of Dubbo filter, see [here](http://dubbo.apache.org/en-us/docs/dev/impls/filter.html).
 
 ## Dubbo resources
 
@@ -62,4 +65,4 @@ flow control, degrade or system load protection. You can implement your own `Dub
 and then register to `DubboFallbackRegistry`. If no fallback is configured, Sentinel will wrap the `BlockException`
 then directly throw it out.
 
-Besides, we can also leverage [Dubbo mock mechanism](http://dubbo.apache.org/#!/docs/user/demos/local-mock.md?lang=en-us) to provide fallback implementation of degraded Dubbo services.
+Besides, we can also leverage [Dubbo mock mechanism](http://dubbo.apache.org/en-us/docs/user/demos/local-mock.html) to provide fallback implementation of degraded Dubbo services.