Introduce new CacheDataImporter and CacheDataExporter interfaces to import and export data into and out from a GemFire/Geode cache on startup.

These new interfaces and APIs are intended to be used in SBDG's auto-configuration when the Spring Boot app using Apache Geode starts up in order to load or save data. Resolves gh-67.
2020-05-04 19:11:13 -07:00
parent fe6e14bb2e
commit 1a19c228be
4 changed files with 296 additions and 0 deletions
--- a/spring-geode/src/main/java/org/springframework/geode/data/CacheDataExporter.java
+++ b/spring-geode/src/main/java/org/springframework/geode/data/CacheDataExporter.java
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2020 the original author or authors.
+ *
+ * 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
+ *
+ *     https://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.springframework.geode.data;
+
+import org.apache.geode.cache.Region;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.DestructionAwareBeanPostProcessor;
+import org.springframework.lang.NonNull;
+
+/**
+ * The {@link CacheDataExporter} interface is a {@link FunctionalInterface} defining a contract for exporting data
+ * from a cache {@link Region}.
+ *
+ * @author John Blum
+ * @see java.lang.FunctionalInterface
+ * @see org.apache.geode.cache.Region
+ * @see org.springframework.beans.factory.config.DestructionAwareBeanPostProcessor
+ * @since 1.3.0
+ */
+@FunctionalInterface
+@SuppressWarnings("rawtypes")
+public interface CacheDataExporter extends DestructionAwareBeanPostProcessor {
+
+	/**
+	 * Exports any data contained in a {@link Region} on destruction.
+	 *
+	 * @param bean {@link Object} bean to evaluate.
+	 * @param beanName {@link String} containing the name of the bean.
+	 * @throws BeansException if exporting data from a {@link Region} fails!
+	 * @see org.apache.geode.cache.Region
+	 * @see #exportFrom(Region)
+	 */
+	@Override
+	default void postProcessBeforeDestruction(Object bean, String beanName) throws BeansException {
+
+		if (bean instanceof Region) {
+			exportFrom((Region) bean);
+		}
+	}
+
+	/**
+	 * Exports data contained in the given {@link Region}.
+	 *
+	 * @param region {@link Region} to export data from.
+	 * @return the given {@link Region}.
+	 * @see org.apache.geode.cache.Region
+	 */
+	@NonNull Region exportFrom(@NonNull Region region);
+
+}
--- a/spring-geode/src/main/java/org/springframework/geode/data/CacheDataImporter.java
+++ b/spring-geode/src/main/java/org/springframework/geode/data/CacheDataImporter.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2020 the original author or authors.
+ *
+ * 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
+ *
+ *     https://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.springframework.geode.data;
+
+import org.apache.geode.cache.Region;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
+
+/**
+ * The {@link CacheDataImporter} interface is a {@link FunctionalInterface} defininig a contract for importing data
+ * into a cache {@link Region}.
+ *
+ * @author John Blum
+ * @see java.lang.FunctionalInterface
+ * @see org.apache.geode.cache.Region
+ * @see org.springframework.beans.factory.config.BeanPostProcessor
+ * @since 1.3.0
+ */
+@FunctionalInterface
+@SuppressWarnings("rawtypes")
+public interface CacheDataImporter extends BeanPostProcessor {
+
+	/**
+	 * Imports data from an external data source into a given {@link Region} after initialization.
+	 *
+	 * @param bean {@link Object} bean to evaluate.
+	 * @param beanName {@link String} containing the name of the bean.
+	 * @throws BeansException if importing data into a {@link Region} fails!
+	 * @see org.apache.geode.cache.Region
+	 * @see #importInto(Region)
+	 */
+	@Nullable @Override
+	default Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
+
+		if (bean instanceof Region) {
+			bean = importInto((Region) bean);
+		}
+
+		return bean;
+	}
+
+	/**
+	 * Imports data into the given {@link Region}.
+	 *
+	 * @param region {@link Region} to import data into.
+	 * @return the given {@link Region}.
+	 * @see org.apache.geode.cache.Region
+	 */
+	@NonNull Region importInto(@NonNull Region region);
+
+}