Revert "Remove RuleItemChangedSubscriber and RuleItemEvent (apache#34099

)"

This reverts commit 0b8df98.

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/RuleItemChangedEvent.java

@@ -0,0 +1,33 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule;
+
+import org.apache.shardingsphere.mode.event.dispatch.DispatchEvent;
+
+/**
+ * Rule item changed event.
+ */
+public interface RuleItemChangedEvent extends DispatchEvent {
+
+    /**
+     * Get rule item type.
+     *
+     * @return rule item type
+     */
+    String getType();
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/alter/AlterNamedRuleItemEvent.java

@@ -0,0 +1,39 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.alter;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Alter named rule item event.
+ */
+@RequiredArgsConstructor
+@Getter
+public final class AlterNamedRuleItemEvent implements AlterRuleItemEvent {
+
+    private final String databaseName;
+
+    private final String itemName;
+
+    private final String activeVersionKey;
+
+    private final String activeVersion;
+
+    private final String type;
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/alter/AlterRuleItemEvent.java

@@ -0,0 +1,47 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.alter;
+
+import org.apache.shardingsphere.mode.event.dispatch.rule.RuleItemChangedEvent;
+
+/**
+ * Alter rule item event.
+ */
+public interface AlterRuleItemEvent extends RuleItemChangedEvent {
+
+    /**
+     * Get database name.
+     *
+     * @return database name
+     */
+    String getDatabaseName();
+
+    /**
+     * Get active version key.
+     *
+     * @return active version key
+     */
+    String getActiveVersionKey();
+
+    /**
+     * Get active version.
+     *
+     * @return active version
+     */
+    String getActiveVersion();
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/alter/AlterUniqueRuleItemEvent.java

@@ -0,0 +1,37 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.alter;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Alter unique rule item event.
+ */
+@RequiredArgsConstructor
+@Getter
+public final class AlterUniqueRuleItemEvent implements AlterRuleItemEvent {
+
+    private final String databaseName;
+
+    private final String activeVersionKey;
+
+    private final String activeVersion;
+
+    private final String type;
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/drop/DropNamedRuleItemEvent.java

@@ -0,0 +1,35 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.drop;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Drop named rule item event.
+ */
+@RequiredArgsConstructor
+@Getter
+public final class DropNamedRuleItemEvent implements DropRuleItemEvent {
+
+    private final String databaseName;
+
+    private final String itemName;
+
+    private final String type;
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/drop/DropRuleItemEvent.java

@@ -0,0 +1,33 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.drop;
+
+import org.apache.shardingsphere.mode.event.dispatch.rule.RuleItemChangedEvent;
+
+/**
+ * Drop rule item event.
+ */
+public interface DropRuleItemEvent extends RuleItemChangedEvent {
+
+    /**
+     * Get database name.
+     *
+     * @return database name
+     */
+    String getDatabaseName();
+}

mode/api/src/main/java/org/apache/shardingsphere/mode/event/dispatch/rule/drop/DropUniqueRuleItemEvent.java

@@ -0,0 +1,33 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.rule.drop;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+/**
+ * Drop unique rule item event.
+ */
+@RequiredArgsConstructor
+@Getter
+public final class DropUniqueRuleItemEvent implements DropRuleItemEvent {
+
+    private final String databaseName;
+
+    private final String type;
+}

mode/core/src/main/java/org/apache/shardingsphere/mode/event/dispatch/builder/RuleConfigurationChangedEventBuilder.java

@@ -0,0 +1,94 @@
+/*
+ * 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.shardingsphere.mode.event.dispatch.builder;
+
+import com.google.common.base.Strings;
+import org.apache.shardingsphere.mode.event.dispatch.DispatchEvent;
+import org.apache.shardingsphere.infra.spi.ShardingSphereServiceLoader;
+import org.apache.shardingsphere.mode.event.DataChangedEvent;
+import org.apache.shardingsphere.mode.event.DataChangedEvent.Type;
+import org.apache.shardingsphere.mode.event.dispatch.rule.RuleItemChangedEvent;
+import org.apache.shardingsphere.mode.event.dispatch.rule.alter.AlterNamedRuleItemEvent;
+import org.apache.shardingsphere.mode.event.dispatch.rule.alter.AlterUniqueRuleItemEvent;
+import org.apache.shardingsphere.mode.event.dispatch.rule.drop.DropNamedRuleItemEvent;
+import org.apache.shardingsphere.mode.event.dispatch.rule.drop.DropUniqueRuleItemEvent;
+import org.apache.shardingsphere.mode.path.rule.RuleNodePath;
+import org.apache.shardingsphere.mode.path.rule.item.NamedRuleItemNodePath;
+import org.apache.shardingsphere.mode.path.rule.item.UniqueRuleItemNodePath;
+import org.apache.shardingsphere.mode.spi.RuleNodePathProvider;
+
+import java.util.Map.Entry;
+import java.util.Optional;
+
+/**
+ * Rule configuration changed event builder.
+ */
+public final class RuleConfigurationChangedEventBuilder {
+
+    /**
+     * Build rule changed event.
+     *
+     * @param databaseName database name
+     * @param event data changed event
+     * @return built event
+     */
+    public Optional<DispatchEvent> build(final String databaseName, final DataChangedEvent event) {
+        for (RuleNodePathProvider each : ShardingSphereServiceLoader.getServiceInstances(RuleNodePathProvider.class)) {
+            Optional<DispatchEvent> result = build(each.getRuleNodePath(), databaseName, event);
+            if (result.isPresent()) {
+                return result;
+            }
+        }
+        return Optional.empty();
+    }
+
+    private Optional<DispatchEvent> build(final RuleNodePath ruleNodePath, final String databaseName, final DataChangedEvent event) {
+        if (!ruleNodePath.getRoot().isValidatedPath(event.getKey()) || Type.DELETED != event.getType() && Strings.isNullOrEmpty(event.getValue())) {
+            return Optional.empty();
+        }
+        for (Entry<String, NamedRuleItemNodePath> entry : ruleNodePath.getNamedItems().entrySet()) {
+            Optional<String> itemName;
+            if (Type.ADDED == event.getType() || Type.UPDATED == event.getType()) {
+                itemName = entry.getValue().getNameByActiveVersion(event.getKey());
+            } else {
+                itemName = entry.getValue().getNameByItemPath(event.getKey());
+            }
+            if (itemName.isPresent()) {
+                return Optional.of(create(databaseName, itemName.get(), event, ruleNodePath.getRoot().getRuleType() + "." + entry.getKey()));
+            }
+        }
+        for (Entry<String, UniqueRuleItemNodePath> entry : ruleNodePath.getUniqueItems().entrySet()) {
+            if (entry.getValue().isActiveVersionPath(event.getKey())) {
+                return Optional.of(create(databaseName, event, ruleNodePath.getRoot().getRuleType() + "." + entry.getKey()));
+            }
+        }
+        return Optional.empty();
+    }
+
+    private RuleItemChangedEvent create(final String databaseName, final String itemName, final DataChangedEvent event, final String type) {
+        return Type.ADDED == event.getType() || Type.UPDATED == event.getType()
+                ? new AlterNamedRuleItemEvent(databaseName, itemName, event.getKey(), event.getValue(), type)
+                : new DropNamedRuleItemEvent(databaseName, itemName, type);
+    }
+
+    private RuleItemChangedEvent create(final String databaseName, final DataChangedEvent event, final String type) {
+        return Type.ADDED == event.getType() || Type.UPDATED == event.getType()
+                ? new AlterUniqueRuleItemEvent(databaseName, event.getKey(), event.getValue(), type)
+                : new DropUniqueRuleItemEvent(databaseName, type);
+    }
+}