Add Feature: Metadata Extraction from Files

pom.xml

@@ -113,6 +113,8 @@ Integrates with Spring Data, Spring Data REST and Apache Solr</description>
         <module>./spring-content-s3-boot-starter</module>
         <module>./spring-content-renditions</module>
         <module>./spring-content-renditions-boot-starter</module>
+        <module>./spring-content-metadata-extraction</module>
+        <module>./spring-content-metadata-extraction-boot-starter</module>
         <module>./spring-content-solr</module>
         <module>./spring-content-solr-boot-starter</module>
         <module>./spring-content-elasticsearch</module>

spring-content-autoconfigure/pom.xml

@@ -58,6 +58,12 @@
 			<version>3.0.17-SNAPSHOT</version>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>com.github.paulcwarren</groupId>
+			<artifactId>spring-content-metadata-extraction</artifactId>
+			<version>3.0.17-SNAPSHOT</version>
+			<optional>true</optional>
+		</dependency>
 <!--		<dependency>-->
 <!--			<groupId>com.github.paulcwarren</groupId>-->
 <!--			<artifactId>spring-content-docx4j</artifactId>-->

spring-content-autoconfigure/src/main/java/internal/org/springframework/content/metadataextraction/boot/autoconfigure/MetadataExtractionContentAutoConfiguration.java

@@ -0,0 +1,41 @@
+/* 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 internal.org.springframework.content.metadataextraction.boot.autoconfigure;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.content.metadataextraction.config.MetadataExtractionConfiguration;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+
+/**
+ * Autoconfiguration class for enabling metadata extraction functionality in a Spring Boot application.
+ * <p>
+ * This configuration class is activated when the {@link MetadataExtractionConfiguration} class is present in the classpath.
+ * </p>
+ * <p>
+ * By including this class, metadata extraction features are automatically configured without requiring explicit registration
+ * of the necessary components, simplifying integration into the application context.
+ * </p>
+ *
+ * @author marcobelligoli
+ */
+@Configuration
+@ConditionalOnClass(MetadataExtractionConfiguration.class)
+@Import(MetadataExtractionConfiguration.class)
+public class MetadataExtractionContentAutoConfiguration {
+
+}

spring-content-autoconfigure/src/main/resources/META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports

@@ -3,6 +3,7 @@ internal.org.springframework.content.fs.boot.autoconfigure.FilesystemContentAuto
 internal.org.springframework.content.jpa.boot.autoconfigure.JpaContentAutoConfiguration
 internal.org.springframework.content.mongo.boot.autoconfigure.MongoContentAutoConfiguration
 internal.org.springframework.content.renditions.boot.autoconfigure.RenditionsContentAutoConfiguration
+internal.org.springframework.content.metadataextraction.boot.autoconfigure.MetadataExtractionContentAutoConfiguration
 internal.org.springframework.content.rest.boot.autoconfigure.ContentRestAutoConfiguration
 internal.org.springframework.content.rest.boot.autoconfigure.HypermediaAutoConfiguration
 internal.org.springframework.content.s3.boot.autoconfigure.S3ContentAutoConfiguration

spring-content-autoconfigure/src/test/java/org/springframework/content/metadataextraction/boot/ContentMetadataExtractionAutoConfigurationTest.java

@@ -0,0 +1,80 @@
+/* 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.springframework.content.metadataextraction.boot;
+
+import com.github.paulcwarren.ginkgo4j.Ginkgo4jConfiguration;
+import com.github.paulcwarren.ginkgo4j.Ginkgo4jRunner;
+import internal.org.springframework.content.s3.boot.autoconfigure.S3ContentAutoConfiguration;
+import internal.org.springframework.content.solr.boot.autoconfigure.SolrAutoConfiguration;
+import internal.org.springframework.content.solr.boot.autoconfigure.SolrExtensionAutoConfiguration;
+import org.junit.runner.RunWith;
+import org.springframework.boot.autoconfigure.AutoConfigurationPackage;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.content.commons.metadataextraction.MetadataExtractionService;
+import org.springframework.content.commons.renditions.Renderable;
+import org.springframework.content.commons.repository.ContentStore;
+import org.springframework.content.metadataextraction.extractors.DefaultMetadataExtractor;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.EnableMBeanExport;
+import org.springframework.jmx.support.RegistrationPolicy;
+import org.springframework.support.TestEntity;
+
+import static com.github.paulcwarren.ginkgo4j.Ginkgo4jDSL.Context;
+import static com.github.paulcwarren.ginkgo4j.Ginkgo4jDSL.Describe;
+import static com.github.paulcwarren.ginkgo4j.Ginkgo4jDSL.It;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.hamcrest.CoreMatchers.nullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * Test class for verifying the functionality of the ContentMetadataExtractionAutoConfiguration.
+ *
+ * @author marcobelligoli
+ */
+@RunWith(Ginkgo4jRunner.class)
+@Ginkgo4jConfiguration(threads = 1)
+public class ContentMetadataExtractionAutoConfigurationTest {
+
+    {
+        Describe("ContentMetadataExtractionAutoConfiguration",
+                 () -> Context("given a default configuration", () -> It("should load the all metadata extractors", () -> {
+
+                     AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+                     context.register(TestConfig.class);
+                     context.refresh();
+
+                     assertThat(context.getBean(MetadataExtractionService.class), is(not(nullValue())));
+                     assertThat(context.getBean(DefaultMetadataExtractor.class), is(not(nullValue())));
+
+                     context.close();
+                 })));
+    }
+
+    @Configuration
+    @AutoConfigurationPackage
+    @EnableAutoConfiguration(exclude = { SolrAutoConfiguration.class, SolrExtensionAutoConfiguration.class, S3ContentAutoConfiguration.class })
+    @EnableMBeanExport(registration = RegistrationPolicy.IGNORE_EXISTING)
+    public static class TestConfig {
+
+    }
+
+    public interface TestEntityContentStore extends ContentStore<TestEntity, String>, Renderable<TestEntity> {
+
+    }
+}

spring-content-commons/src/main/java/internal/org/springframework/content/commons/metadataextraction/MetadataExtractionServiceImpl.java

@@ -0,0 +1,54 @@
+/* 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 internal.org.springframework.content.commons.metadataextraction;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.content.commons.metadataextraction.MetadataExtractionService;
+import org.springframework.content.commons.metadataextraction.MetadataExtractor;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Implementation of the {@link MetadataExtractionService} interface.
+ *
+ * @author marcobelligoli
+ */
+public class MetadataExtractionServiceImpl implements MetadataExtractionService {
+
+    private final List<MetadataExtractor> metadataExtractorList = new ArrayList<>();
+
+    @Autowired(required = false)
+    public MetadataExtractionServiceImpl(MetadataExtractor... metadataExtractors) {
+
+        Collections.addAll(this.metadataExtractorList, metadataExtractors);
+    }
+
+    @Override
+    public Map<String, Object> extractMetadata(File file) {
+
+        Map<String, Object> fullMetadataMap = new HashMap<>();
+        for (var metadataExtractor : metadataExtractorList) {
+            fullMetadataMap.putAll(metadataExtractor.extractMetadata(file));
+        }
+        return fullMetadataMap;
+    }
+}

spring-content-commons/src/main/java/org/springframework/content/commons/metadataextraction/MetadataExtractionService.java

@@ -0,0 +1,45 @@
+/* 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.springframework.content.commons.metadataextraction;
+
+import java.io.File;
+import java.util.Map;
+
+/**
+ * A service that extracts metadata from a given file.
+ * <p>
+ * The extracted metadata will be returned as a map where the keys represent
+ * the metadata property names and the values represent the respective metadata values.
+ * </p>
+ * <p>
+ * This service retrieves all instances of {@link MetadataExtractor} present in the Spring context and,
+ * for each of them, performs metadata extraction from the provided file.
+ * </p>
+ *
+ * @author marcobelligoli
+ */
+public interface MetadataExtractionService {
+
+    /**
+     * Extracts metadata from the specified file.
+     *
+     * @param file the file from which metadata will be extracted
+     * @return a map containing the extracted metadata, where keys represent
+     * metadata property names, and values represent the respective metadata values
+     */
+    Map<String, Object> extractMetadata(File file);
+}

spring-content-commons/src/main/java/org/springframework/content/commons/metadataextraction/MetadataExtractor.java

@@ -0,0 +1,36 @@
+/* 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.springframework.content.commons.metadataextraction;
+
+import java.io.File;
+import java.util.Map;
+
+/**
+ * Interface of MetadataExtractor component
+ *
+ * @author marcobelligoli
+ */
+public interface MetadataExtractor {
+
+    /**
+     * Extracts metadata from the given file.
+     *
+     * @param file the file from which metadata is to be extracted
+     * @return a map containing metadata as key-value pairs
+     */
+    Map<String, Object> extractMetadata(File file);
+}