Enable index modification via IndexOperations.

Introduce IndexOptions that can be used to alter an existing index via IndexOperations.

See: #4348

Author: christophstrobl

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/UncategorizedMongoDbException.java

@@ -16,12 +16,13 @@
 package org.springframework.data.mongodb;
 
 import org.springframework.dao.UncategorizedDataAccessException;
+import org.springframework.lang.Nullable;
 
 public class UncategorizedMongoDbException extends UncategorizedDataAccessException {
 
 	private static final long serialVersionUID = -2336595514062364929L;
 
-	public UncategorizedMongoDbException(String msg, Throwable cause) {
+	public UncategorizedMongoDbException(String msg, @Nullable Throwable cause) {
 		super(msg, cause);
 	}
 }

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/DefaultIndexOperations.java

@@ -22,13 +22,15 @@
 import org.bson.Document;
 import org.springframework.dao.DataAccessException;
 import org.springframework.data.mongodb.MongoDatabaseFactory;
+import org.springframework.data.mongodb.UncategorizedMongoDbException;
 import org.springframework.data.mongodb.core.convert.QueryMapper;
 import org.springframework.data.mongodb.core.index.IndexDefinition;
 import org.springframework.data.mongodb.core.index.IndexInfo;
 import org.springframework.data.mongodb.core.index.IndexOperations;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
+import org.springframework.util.NumberUtils;
 
 import com.mongodb.MongoException;
 import com.mongodb.client.MongoCollection;
@@ -155,6 +157,20 @@ public void dropIndex(final String name) {
 
 	}
 
+	@Override
+	public void alterIndex(String name, org.springframework.data.mongodb.core.index.IndexOptions options) {
+
+		Document indexOptions = new Document("name", name);
+		indexOptions.putAll(options.toDocument());
+
+		Document result = mongoOperations
+				.execute(db -> db.runCommand(new Document("collMod", collectionName).append("index", indexOptions)));
+
+		if(NumberUtils.convertNumberToTargetClass(result.get("ok", (Number) 0), Integer.class) != 1) {
+			throw new UncategorizedMongoDbException("Index '%s' could not be modified. Response was %s".formatted(name, result.toJson()), null);
+		}
+	}
+
 	public void dropAllIndexes() {
 		dropIndex("*");
 	}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/DefaultReactiveIndexOperations.java

@@ -22,13 +22,15 @@
 import java.util.Optional;
 
 import org.bson.Document;
+import org.springframework.data.mongodb.UncategorizedMongoDbException;
 import org.springframework.data.mongodb.core.convert.QueryMapper;
 import org.springframework.data.mongodb.core.index.IndexDefinition;
 import org.springframework.data.mongodb.core.index.IndexInfo;
 import org.springframework.data.mongodb.core.index.ReactiveIndexOperations;
 import org.springframework.data.mongodb.core.mapping.MongoPersistentEntity;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
+import org.springframework.util.NumberUtils;
 
 import com.mongodb.client.model.IndexOptions;
 
@@ -104,6 +106,22 @@ public Mono<String> ensureIndex(final IndexDefinition indexDefinition) {
 		}).next();
 	}
 
+	@Override
+	public Mono<Void> alterIndex(String name, org.springframework.data.mongodb.core.index.IndexOptions options) {
+
+		return mongoOperations.execute(db -> {
+			Document indexOptions = new Document("name", name);
+			indexOptions.putAll(options.toDocument());
+
+			return Flux.from(db.runCommand(new Document("collMod", collectionName).append("index", indexOptions)))
+					.doOnNext(result -> {
+						if(NumberUtils.convertNumberToTargetClass(result.get("ok", (Number) 0), Integer.class) != 1) {
+							throw new UncategorizedMongoDbException("Index '%s' could not be modified. Response was %s".formatted(name, result.toJson()), null);
+						}
+					});
+		}).then();
+	}
+
 	@Nullable
 	private MongoPersistentEntity<?> lookupPersistentEntity(String collection) {
 

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/Index.java

@@ -24,6 +24,7 @@
 
 import org.bson.Document;
 import org.springframework.data.domain.Sort.Direction;
+import org.springframework.data.mongodb.core.index.IndexOptions.Unique;
 import org.springframework.data.mongodb.core.query.Collation;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -39,11 +40,9 @@ public class Index implements IndexDefinition {
 
 	private final Map<String, Direction> fieldSpec = new LinkedHashMap<String, Direction>();
 	private @Nullable String name;
-	private boolean unique = false;
 	private boolean sparse = false;
 	private boolean background = false;
-	private boolean hidden = false;
-	private long expire = -1;
+	private final IndexOptions options = IndexOptions.none();
 	private Optional<IndexFilter> filter = Optional.empty();
 	private Optional<Collation> collation = Optional.empty();
 
@@ -71,7 +70,8 @@ public Index named(String name) {
 	 *      "https://docs.mongodb.org/manual/core/index-unique/">https://docs.mongodb.org/manual/core/index-unique/</a>
 	 */
 	public Index unique() {
-		this.unique = true;
+
+		this.options.setUnique(Unique.YES);
 		return this;
 	}
 
@@ -108,7 +108,8 @@ public Index background() {
 	 * @since 4.1
 	 */
 	public Index hidden() {
-		this.hidden = true;
+
+		options.setHidden(true);
 		return this;
 	}
 
@@ -148,7 +149,7 @@ public Index expire(Duration timeout) {
 	public Index expire(long value, TimeUnit unit) {
 
 		Assert.notNull(unit, "TimeUnit for expiration must not be null");
-		this.expire = unit.toSeconds(value);
+		options.setExpire(Duration.ofSeconds(unit.toSeconds(value)));
 		return this;
 	}
 
@@ -200,21 +201,13 @@ public Document getIndexOptions() {
 		if (StringUtils.hasText(name)) {
 			document.put("name", name);
 		}
-		if (unique) {
-			document.put("unique", true);
-		}
 		if (sparse) {
 			document.put("sparse", true);
 		}
 		if (background) {
 			document.put("background", true);
 		}
-		if (hidden) {
-			document.put("hidden", true);
-		}
-		if (expire >= 0) {
-			document.put("expireAfterSeconds", expire);
-		}
+		document.putAll(options.toDocument());
 
 		filter.ifPresent(val -> document.put("partialFilterExpression", val.getFilterObject()));
 		collation.ifPresent(val -> document.append("collation", val.toDocument()));

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexOperations.java

@@ -35,6 +35,14 @@ public interface IndexOperations {
 	 */
 	String ensureIndex(IndexDefinition indexDefinition);
 
+	/**
+	 * Drops an index from this collection.
+	 *
+	 * @param name name of index to hide.
+	 * @since 4.1
+	 */
+	void alterIndex(String name, IndexOptions options);
+
 	/**
 	 * Drops an index from this collection.
 	 *

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexOperationsAdapter.java

@@ -50,6 +50,11 @@ public void dropIndex(String name) {
 				reactiveIndexOperations.dropIndex(name).block();
 			}
 
+			@Override
+			public void alterIndex(String name, IndexOptions options) {
+				reactiveIndexOperations.alterIndex(name, options);
+			}
+
 			@Override
 			public void dropAllIndexes() {
 				reactiveIndexOperations.dropAllIndexes().block();

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexOptions.java

@@ -0,0 +1,160 @@
+/*
+ * Copyright 2023 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.data.mongodb.core.index;
+
+import java.time.Duration;
+
+import org.bson.Document;
+import org.springframework.lang.Nullable;
+
+/**
+ * Changeable properties of an index. Can be used for index creation and modification.
+ *
+ * @author Christoph Strobl
+ * @since 4.1
+ */
+public class IndexOptions {
+
+	@Nullable
+	private Duration expire;
+
+	@Nullable
+	private Boolean hidden;
+
+	@Nullable
+	private Unique unique;
+
+	public enum Unique {
+
+		NO,
+
+		/**
+		 * When unique is true the index rejects duplicate entries.
+		 */
+		YES,
+
+		/**
+		 * An existing index is not checked for pre-existing, duplicate index entries but inserting new duplicate entries
+		 * fails.
+		 */
+		PREPARE
+	}
+
+	/**
+	 * @return new empty instance of {@link IndexOptions}.
+	 */
+	public static IndexOptions none() {
+		return new IndexOptions();
+	}
+
+	/**
+	 * @return new instance of {@link IndexOptions} having the {@link Unique#YES} flag set.
+	 */
+	public static IndexOptions unique() {
+
+		IndexOptions options = new IndexOptions();
+		options.unique = Unique.YES;
+		return options;
+	}
+
+	/**
+	 * @return new instance of {@link IndexOptions} having the hidden flag set.
+	 */
+	public static IndexOptions hidden() {
+
+		IndexOptions options = new IndexOptions();
+		options.hidden = true;
+		return options;
+	}
+
+	/**
+	 * @return new instance of {@link IndexOptions} with given expiration.
+	 */
+	public static IndexOptions expireAfter(Duration duration) {
+
+		IndexOptions options = new IndexOptions();
+		options.unique = Unique.YES;
+		return options;
+	}
+
+	/**
+	 * @return the expiration time. A {@link Duration#isNegative() negative value} represents no expiration, {@literal null} if not set.
+	 */
+	public Duration getExpire() {
+		return expire;
+	}
+
+	/**
+	 * @param expire must not be {@literal null}.
+	 */
+	public void setExpire(Duration expire) {
+		this.expire = expire;
+	}
+
+	/**
+	 * @return {@literal true} if hidden, {@literal null} if not set.
+	 */
+	@Nullable
+	public Boolean isHidden() {
+		return hidden;
+	}
+
+	/**
+	 * @param hidden
+	 */
+	public void setHidden(boolean hidden) {
+		this.hidden = hidden;
+	}
+
+	/**
+	 * @return the unique property value, {@literal null} if not set.
+	 */
+	@Nullable
+	public Unique getUnique() {
+		return unique;
+	}
+
+	/**
+	 * @param unique must not be {@literal null}.
+	 */
+	public void setUnique(Unique unique) {
+		this.unique = unique;
+	}
+
+	/**
+	 * @return the store native representation
+	 */
+	public Document toDocument() {
+
+		Document document = new Document();
+		if(unique != null) {
+			switch (unique) {
+				case NO -> document.put("unique", false);
+				case YES -> document.put("unique", true);
+				case PREPARE -> document.put("prepareUnique", true);
+			}
+		}
+		if(hidden != null) {
+			document.put("hidden", hidden);
+		}
+
+
+		if (expire != null && !expire.isNegative()) {
+			document.put("expireAfterSeconds", expire.getSeconds());
+		}
+		return document;
+	}
+}

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/ReactiveIndexOperations.java

@@ -35,6 +35,15 @@ public interface ReactiveIndexOperations {
 	 */
 	Mono<String> ensureIndex(IndexDefinition indexDefinition);
 
+	/**
+	 * Alters the index with given {@literal name}.
+	 *
+	 * @param name name of index to hide.
+	 * @param
+	 * @since 4.1
+	 */
+	Mono<Void> alterIndex(String name, IndexOptions options);
+
 	/**
 	 * Drops an index from this collection.
 	 *

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/DefaultIndexOperationsIntegrationTests.java

@@ -197,6 +197,16 @@ void shouldCreateHiddenIndex() {
 		assertThat(info.isHidden()).isTrue();
 	}
 
+	@Test // GH-4348
+	void alterIndexShouldAllowHiding() {
+
+		collection.createIndex(new Document("a", 1), new IndexOptions().name("my-index"));
+
+		indexOps.alterIndex("my-index", org.springframework.data.mongodb.core.index.IndexOptions.hidden());
+		IndexInfo info = findAndReturnIndexInfo(indexOps.getIndexInfo(), "my-index");
+		assertThat(info.isHidden()).isTrue();
+	}
+
 	private IndexInfo findAndReturnIndexInfo(org.bson.Document keys) {
 		return findAndReturnIndexInfo(indexOps.getIndexInfo(), keys);
 	}