Add builder pattern to MongoDBAtlasVectorStore and refactor package name

The MongoDBAtlasVectorStore implementation has been enhanced with a builder
pattern to provide a more flexible and type-safe way to configure the vector
store. This change improves the developer experience by making the API more
intuitive and less error-prone.

The old constructors and configuration classes have been deprecated in favor
of the builder pattern. This aligns with Spring's best practices for
configuration APIs.

Additionally, the package has been refactored to
org.springframework.ai.vectorstore.mongodb.atlas to avoid having
multiple vector store modules share the same package name.

Documentation has been updated to reflect these changes and provide
examples of using the new builder pattern.review

Author: sobychacko

spring-ai-docs/src/main/antora/modules/ROOT/pages/api/vectordbs/mongodb.adoc

@@ -17,13 +17,14 @@
 package org.springframework.ai.autoconfigure.vectorstore.mongo;
 
 import java.util.Arrays;
+import java.util.List;
 
 import io.micrometer.observation.ObservationRegistry;
 
 import org.springframework.ai.embedding.BatchingStrategy;
 import org.springframework.ai.embedding.EmbeddingModel;
 import org.springframework.ai.embedding.TokenCountBatchingStrategy;
-import org.springframework.ai.vectorstore.MongoDBAtlasVectorStore;
+import org.springframework.ai.vectorstore.mongodb.atlas.MongoDBAtlasVectorStore;
 import org.springframework.ai.vectorstore.observation.VectorStoreObservationConvention;
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfiguration;
@@ -34,6 +35,7 @@
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.mongodb.core.MongoTemplate;
 import org.springframework.data.mongodb.core.convert.MongoCustomConversions;
+import org.springframework.util.CollectionUtils;
 import org.springframework.util.MimeType;
 import org.springframework.util.StringUtils;
 
@@ -64,25 +66,35 @@ MongoDBAtlasVectorStore vectorStore(MongoTemplate mongoTemplate, EmbeddingModel
 			ObjectProvider<VectorStoreObservationConvention> customObservationConvention,
 			BatchingStrategy batchingStrategy) {
 
-		var builder = MongoDBAtlasVectorStore.MongoDBVectorStoreConfig.builder();
-
-		if (StringUtils.hasText(properties.getCollectionName())) {
-			builder.withCollectionName(properties.getCollectionName());
+		MongoDBAtlasVectorStore.MongoDBBuilder builder = MongoDBAtlasVectorStore.builder()
+			.mongoTemplate(mongoTemplate)
+			.embeddingModel(embeddingModel)
+			.initializeSchema(properties.isInitializeSchema())
+			.observationRegistry(observationRegistry.getIfUnique(() -> ObservationRegistry.NOOP))
+			.customObservationConvention(customObservationConvention.getIfAvailable(() -> null))
+			.batchingStrategy(batchingStrategy);
+
+		String collectionName = properties.getCollectionName();
+		if (StringUtils.hasText(collectionName)) {
+			builder.collectionName(collectionName);
 		}
-		if (StringUtils.hasText(properties.getPathName())) {
-			builder.withPathName(properties.getPathName());
+
+		String pathName = properties.getPathName();
+		if (StringUtils.hasText(pathName)) {
+			builder.pathName(pathName);
 		}
-		if (StringUtils.hasText(properties.getIndexName())) {
-			builder.withVectorIndexName(properties.getIndexName());
+
+		String indexName = properties.getIndexName();
+		if (StringUtils.hasText(indexName)) {
+			builder.vectorIndexName(indexName);
 		}
-		if (!properties.getMetadataFieldsToFilter().isEmpty()) {
-			builder.withMetadataFieldsToFilter(properties.getMetadataFieldsToFilter());
+
+		List<String> metadataFields = properties.getMetadataFieldsToFilter();
+		if (!CollectionUtils.isEmpty(metadataFields)) {
+			builder.metadataFieldsToFilter(metadataFields);
 		}
-		MongoDBAtlasVectorStore.MongoDBVectorStoreConfig config = builder.build();
 
-		return new MongoDBAtlasVectorStore(mongoTemplate, embeddingModel, config, properties.isInitializeSchema(),
-				observationRegistry.getIfUnique(() -> ObservationRegistry.NOOP),
-				customObservationConvention.getIfAvailable(() -> null), batchingStrategy);
+		return builder.build();
 	}
 
 	@Bean

spring-ai-spring-boot-autoconfigure/src/main/java/org/springframework/ai/autoconfigure/vectorstore/mongo/MongoDBAtlasVectorStoreAutoConfiguration.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.ai.vectorstore;
+package org.springframework.ai.vectorstore.mongodb.atlas;
 
 import org.springframework.ai.vectorstore.filter.Filter;
 import org.springframework.ai.vectorstore.filter.converter.AbstractFilterExpressionConverter;