Add integration testcase for testing ServiceConfig and RegistryProtoc…

…ol (apache#8246)

* Add integration testcase for testing ServiceConfig and RegistryProtocol

1. define an integration framework
2. test RegistoryProtocol with dubbo protocol

* perf: Set INSTANCE as null after shutdow

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/ZooKeeperServerTesting.java

@@ -0,0 +1,187 @@
+/*
+ * 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 org.apache.dubbo;
+
+import org.apache.dubbo.common.utils.NetUtils;
+import org.apache.zookeeper.server.ServerConfig;
+import org.apache.zookeeper.server.ZooKeeperServerMain;
+import org.apache.zookeeper.server.quorum.QuorumPeerConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.lang.reflect.Method;
+import java.util.Properties;
+import java.util.UUID;
+
+/**
+ * The zookeeper server is just for testing.
+ * <p>
+ * Note: It can only be used if the following conditions are satisfied
+ * <p>1. Integration testcase instead of unit testcase
+ * <p>2. You can use only one zookeeper instance per Package, because the zookeeper is a static global instance.
+ */
+public class ZooKeeperServerTesting {
+
+    private static final Logger logger = LoggerFactory.getLogger(ZooKeeperServerTesting.class);
+
+    /**
+     * Define a static zookeeper instance.
+     */
+    private static volatile InnerZooKeeper INSTANCE;
+
+    /**
+     * Start the zookeeper instance.
+     */
+    public static void start() {
+        if (INSTANCE == null) {
+            INSTANCE = new InnerZooKeeper(NetUtils.getAvailablePort());
+            INSTANCE.start();
+        }
+    }
+
+    /**
+     * Returns the zookeeper server's port.
+     */
+    public static int getPort() {
+        return INSTANCE.getClientPort();
+    }
+
+    /**
+     * Shutdown the zookeeper instance.
+     */
+    public static void shutdown() {
+        if (INSTANCE != null) {
+            INSTANCE.shutdown();
+            INSTANCE = null;
+        }
+    }
+
+    /**
+     * from: https://github.com/spring-projects/spring-xd/blob/v1.3.1.RELEASE/spring-xd-dirt/src/main/java/org/springframework/xd/dirt/zookeeper/ZooKeeperUtils.java
+     * <p>
+     * Helper class to start an embedded instance of standalone (non clustered) ZooKeeper.
+     * <p>
+     * NOTE: at least an external standalone server (if not an ensemble) are recommended, even for
+     */
+    private static class InnerZooKeeper {
+
+        /**
+         * ZooKeeper client port. This will be determined dynamically upon startup.
+         */
+        private final int clientPort;
+
+        /**
+         * Thread for running the ZooKeeper server.
+         */
+        private volatile Thread zkServerThread;
+
+        /**
+         * ZooKeeper server.
+         */
+        private volatile ZooKeeperServerMain zkServer;
+
+        /**
+         * Construct an EmbeddedZooKeeper with the provided port.
+         *
+         * @param clientPort port for ZooKeeper server to bind to
+         */
+        public InnerZooKeeper(int clientPort) {
+            this.clientPort = clientPort;
+        }
+
+        /**
+         * Returns the port that clients should use to connect to this embedded server.
+         *
+         * @return dynamically determined client port
+         */
+        public int getClientPort() {
+            return this.clientPort;
+        }
+
+        /**
+         * Checks if the zookeeper server is running.
+         */
+        public boolean isRunning() {
+            return (zkServerThread != null);
+        }
+
+        /**
+         * Start the ZooKeeper server in a background thread.
+         * <p>
+         * any exceptions thrown during startup or execution.
+         */
+        private synchronized void start() {
+            if (zkServerThread == null) {
+                zkServerThread = new Thread(() -> {
+                    try {
+                        Properties properties = new Properties();
+                        File file = new File(System.getProperty("java.io.tmpdir")
+                            + File.separator + UUID.randomUUID());
+                        file.deleteOnExit();
+                        properties.setProperty("dataDir", file.getAbsolutePath());
+                        properties.setProperty("clientPort", String.valueOf(clientPort));
+
+                        QuorumPeerConfig quorumPeerConfig = new QuorumPeerConfig();
+                        quorumPeerConfig.parseProperties(properties);
+
+                        zkServer = new ZooKeeperServerMain();
+                        ServerConfig configuration = new ServerConfig();
+                        configuration.readFrom(quorumPeerConfig);
+
+                        zkServer.runFromConfig(configuration);
+                    } catch (Exception e) {
+                        logger.error("Exception running embedded ZooKeeper", e);
+                    }
+                }, "zookeeper-server-for-test");
+                zkServerThread.setDaemon(true);
+                zkServerThread.start();
+            }
+        }
+
+        /**
+         * Shutdown the ZooKeeper server.
+         */
+        private synchronized void shutdown() {
+            if (zkServerThread != null) {
+                // The shutdown method is protected...thus this hack to invoke it.
+                // This will log an exception on shutdown; see
+                // https://issues.apache.org/jira/browse/ZOOKEEPER-1873 for details.
+                try {
+                    Method shutdown = ZooKeeperServerMain.class.getDeclaredMethod("shutdown");
+                    shutdown.setAccessible(true);
+                    shutdown.invoke(zkServer);
+                } catch (Exception e) {
+                    throw new RuntimeException(e);
+                }
+
+                // It is expected that the thread will exit after
+                // the server is shutdown; this will block until
+                // the shutdown is complete.
+                try {
+                    zkServerThread.join(5000);
+                    zkServerThread = null;
+                } catch (InterruptedException e) {
+                    Thread.currentThread().interrupt();
+                    logger.warn("Interrupted while waiting for embedded ZooKeeper to exit");
+                    // abandoning zk thread
+                    zkServerThread = null;
+                }
+            }
+        }
+    }
+}

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/integration/AbstractIntegrationTest.java

@@ -0,0 +1,81 @@
+/*
+ * 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 org.apache.dubbo.integration;
+
+import org.apache.dubbo.ZooKeeperServerTesting;
+import org.apache.dubbo.config.bootstrap.DubboBootstrap;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+/**
+ * This abstraction class will implement some methods as base.
+ * @param <T> the type of subclass of {@link IntegrationService}.
+ */
+public abstract class AbstractIntegrationTest<T> implements IntegrationTest {
+
+    private static final Logger logger = LoggerFactory.getLogger(AbstractIntegrationTest.class);
+
+    /**
+     * Start global config only once.
+     */
+    @BeforeAll
+    public static void beforeAll() {
+        //start zookeeper only once
+        ZooKeeperServerTesting.start();
+    }
+
+    @BeforeEach
+    public void before() {
+        logger.info(getClass().getSimpleName()+ " testcase is beginning...");
+        DubboBootstrap.reset();
+        this.initialize();
+    }
+
+    @Test
+    @Override
+    public void integrate() {
+        this.process();
+    }
+
+    /**
+     * This abstract method should be implement by all subclass.
+     *
+     */
+    public abstract void process();
+
+    @AfterEach
+    public void after() {
+        this.destroy();
+        DubboBootstrap.reset();
+        logger.info(getClass().getSimpleName()+ " testcase is ending...");
+    }
+
+    /**
+     * Destroy all global resources.
+     */
+    @AfterAll
+    public static void afterAll() {
+        // destroy zookeeper only once
+        ZooKeeperServerTesting.shutdown();
+    }
+}

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/integration/IntegrationService.java

@@ -0,0 +1,25 @@
+/*
+ * 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 org.apache.dubbo.integration;
+
+/**
+ * This interface for integration testcases.
+ */
+public interface IntegrationService {
+
+    String hello(String name);
+}

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/integration/IntegrationTest.java

@@ -0,0 +1,38 @@
+/*
+ * 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 org.apache.dubbo.integration;
+
+/**
+ * The interface for integration testcases.
+ */
+public interface IntegrationTest {
+
+    /**
+     * Initialize all needed resources.
+     */
+    void initialize();
+
+    /**
+     * Run the integration testcases.
+     */
+    void integrate();
+
+    /**
+     * Release all resources.
+     */
+    void destroy();
+}