DATAMONGO-1467 - Support partial filter expressions in indexing.

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

@@ -173,7 +173,9 @@ private List<IndexInfo> getIndexData(List<DBObject> dbObjectList) {
 					boolean dropDuplicates = ix.containsField("dropDups") ? (Boolean) ix.get("dropDups") : false;
 					boolean sparse = ix.containsField("sparse") ? (Boolean) ix.get("sparse") : false;
 					String language = ix.containsField("default_language") ? (String) ix.get("default_language") : "";
-					indexInfoList.add(new IndexInfo(indexFields, name, unique, dropDuplicates, sparse, language));
+					String partialFilter = ix.containsField("partialFilterExpression")
+							? ix.get("partialFilterExpression").toString() : "";
+					indexInfoList.add(new IndexInfo(indexFields, name, unique, dropDuplicates, sparse, language, partialFilter));
 				}
 
 				return indexInfoList;

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

@@ -20,6 +20,7 @@
 import java.util.Map.Entry;
 import java.util.concurrent.TimeUnit;
 
+import com.mongodb.util.JSON;
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.data.mongodb.core.query.Order;
 import org.springframework.util.Assert;
@@ -31,6 +32,7 @@
 /**
  * @author Oliver Gierke
  * @author Christoph Strobl
+ * @author Christian Schneider
  */
 @SuppressWarnings("deprecation")
 public class Index implements IndexDefinition {
@@ -63,6 +65,8 @@ public enum Duplicates {
 
 	private long expire = -1;
 
+	private DBObject partialFilter;
+
 	public Index() {}
 
 	public Index(String key, Direction direction) {
@@ -164,6 +168,19 @@ public Index expire(long value, TimeUnit unit) {
 		return this;
 	}
 
+	/**
+	 * @see http://docs.mongodb.com/manual/core/index-partial/
+	 * @return
+	 */
+	public Index partialFilter(String partialFilter) {
+		if(StringUtils.hasText(partialFilter)) {
+			this.partialFilter = (DBObject) JSON.parse(partialFilter);
+		} else {
+			this.partialFilter = null;
+		}
+		return this;
+	}
+
 	/**
 	 * @see http://docs.mongodb.org/manual/core/index-creation/#index-creation-duplicate-dropping
 	 * @param duplicates
@@ -212,6 +229,9 @@ public DBObject getIndexOptions() {
 		if (expire >= 0) {
 			dbo.put("expireAfterSeconds", expire);
 		}
+		if (partialFilter != null) {
+			dbo.put("partialFilterExpression", partialFilter);
+		}
 
 		return dbo;
 	}

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

@@ -27,6 +27,7 @@
  * @author Mark Pollack
  * @author Oliver Gierke
  * @author Christoph Strobl
+ * @author Christian Schneider
  */
 public class IndexInfo {
 
@@ -37,6 +38,7 @@ public class IndexInfo {
 	private final boolean dropDuplicates;
 	private final boolean sparse;
 	private final String language;
+	private final String partialFilter;
 
 	/**
 	 * @deprecated Will be removed in 1.7. Please use {@link #IndexInfo(List, String, boolean, boolean, boolean, String)}
@@ -51,15 +53,31 @@ public IndexInfo(List<IndexField> indexFields, String name, boolean unique, bool
 		this(indexFields, name, unique, dropDuplicates, sparse, "");
 	}
 
+	/**
+	 * @deprecated Will be removed in 1.7. Please use {@link #IndexInfo(List, String, boolean, boolean, boolean, String)}
+	 * @param indexFields
+	 * @param name
+	 * @param unique
+	 * @param dropDuplicates
+	 * @param sparse
+	 * @param language
+	 */
+	@Deprecated
 	public IndexInfo(List<IndexField> indexFields, String name, boolean unique, boolean dropDuplicates, boolean sparse,
 			String language) {
+		this(indexFields, name, unique, dropDuplicates, sparse, "", "");
+	}
+
+	public IndexInfo(List<IndexField> indexFields, String name, boolean unique, boolean dropDuplicates, boolean sparse,
+			String language, String partialFilter) {
 
 		this.indexFields = Collections.unmodifiableList(indexFields);
 		this.name = name;
 		this.unique = unique;
 		this.dropDuplicates = dropDuplicates;
 		this.sparse = sparse;
 		this.language = language;
+		this.partialFilter = partialFilter;
 	}
 
 	/**
@@ -105,6 +123,10 @@ public boolean isSparse() {
 		return sparse;
 	}
 
+	public String getPartialFilter() {
+		return partialFilter;
+	}
+
 	/**
 	 * @return
 	 * @since 1.6
@@ -116,7 +138,7 @@ public String getLanguage() {
 	@Override
 	public String toString() {
 		return "IndexInfo [indexFields=" + indexFields + ", name=" + name + ", unique=" + unique + ", dropDuplicates="
-				+ dropDuplicates + ", sparse=" + sparse + ", language=" + language + "]";
+				+ dropDuplicates + ", sparse=" + sparse + ", language=" + language + ", partialFilter=" + partialFilter + "]";
 	}
 
 	@Override
@@ -130,6 +152,7 @@ public int hashCode() {
 		result = prime * result + (sparse ? 1231 : 1237);
 		result = prime * result + (unique ? 1231 : 1237);
 		result = prime * result + ObjectUtils.nullSafeHashCode(language);
+		result = prime * result + ((partialFilter == null) ? 0 : partialFilter.hashCode());
 		return result;
 	}
 
@@ -168,6 +191,13 @@ public boolean equals(Object obj) {
 		if (unique != other.unique) {
 			return false;
 		}
+		if(partialFilter == null) {
+			if(other.partialFilter != null) {
+				return false;
+			}
+		} else if (!partialFilter.equals(other.partialFilter)) {
+			return false;
+		}
 		if (!ObjectUtils.nullSafeEquals(language, other.language)) {
 			return false;
 		}

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

@@ -30,6 +30,7 @@
  * @author Thomas Darimont
  * @author Christoph Strobl
  * @author Jordi Llach
+ * @author Christian Schneider
  */
 @Target({ElementType.ANNOTATION_TYPE, ElementType.FIELD})
 @Retention(RetentionPolicy.RUNTIME)
@@ -134,4 +135,12 @@
 	 * @return
 	 */
 	int expireAfterSeconds() default -1;
+
+	/**
+	 * Takes a MongoDB JSON string as filter. If set the index will be applied to documents matching the filter only.
+	 * 
+	 * @see https://docs.mongodb.com/manual/core/index-partial/
+	 * @return
+	 */
+	String partialFilter() default "";
 }

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

@@ -396,6 +396,10 @@ protected IndexDefinitionHolder createIndexDefinition(String dotPath, String fal
 			indexDefinition.expire(index.expireAfterSeconds(), TimeUnit.SECONDS);
 		}
 
+		if (index.partialFilter() != null) {
+			indexDefinition.partialFilter(index.partialFilter());
+		}
+
 		return new IndexDefinitionHolder(dotPath, indexDefinition, collection);
 	}
 

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

@@ -38,6 +38,7 @@
 import java.util.Map;
 
 import org.bson.types.ObjectId;
+import org.hamcrest.core.IsNull;
 import org.joda.time.DateTime;
 import org.junit.After;
 import org.junit.Before;
@@ -420,6 +421,23 @@ public void testReadIndexInfoForIndicesCreatedViaMongoShellCommands() throws Exc
 		assertThat(field, is(IndexField.create("age", Direction.DESC)));
 	}
 
+	/**
+	 * @see DATAMONGO-1467
+	 */
+	@Test
+	public void testReadIndexInfoHavingAPartialFilterExpression() throws Exception {
+
+		String command = "db." + template.getCollectionName(Person.class)
+				+ ".createIndex({'age':-1}, {'partialFilterExpression': { 'age' : { '$exists' : true}}})";
+		template.indexOps(Person.class).dropAllIndexes();
+
+		assertThat(template.indexOps(Person.class).getIndexInfo().isEmpty(), is(true));
+		factory.getDb().eval(command);
+
+		IndexInfo info = template.indexOps(Person.class).getIndexInfo().get(1);
+		assertThat(info.getPartialFilter(), is("{ \"age\" : { \"$exists\" : true}}"));
+	}
+
 	@Test
 	public void testProperHandlingOfDifferentIdTypesWithMappingMongoConverter() throws Exception {
 		testProperHandlingOfDifferentIdTypes(this.mappingTemplate);

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

@@ -22,6 +22,7 @@
 import java.util.Collections;
 import java.util.Date;
 
+import com.mongodb.util.JSON;
 import org.hamcrest.core.IsEqual;
 import org.junit.Before;
 import org.junit.Test;
@@ -56,6 +57,7 @@
  * @author Johno Crawford
  * @author Christoph Strobl
  * @author Thomas Darimont
+ * @author Christian Schneider
  */
 @RunWith(MockitoJUnitRunner.class)
 public class MongoPersistentEntityIndexCreatorUnitTests {
@@ -185,6 +187,19 @@ public void autoGeneratedIndexNameShouldGenerateNoName() {
 		assertThat(optionsCaptor.getValue(), is(new BasicDBObjectBuilder().get()));
 	}
 
+	/**
+	 * @see DATAMONGO-1467
+	 */
+	@Test
+	public void indexCreationShouldUsePartialFilterExpression() {
+
+		MongoMappingContext mappingContext = prepareMappingContext(EntityWithPartialFilterIndex.class);
+		new MongoPersistentEntityIndexCreator(mappingContext, factory);
+
+		assertThat(keysCaptor.getValue().keySet(), hasItem("lastname"));
+		assertThat(optionsCaptor.getValue().get("partialFilterExpression"), is(JSON.parse("{ \"lastname\" : { \"$exists\" : true } }")));
+	}
+
 	/**
 	 * @see DATAMONGO-367
 	 */
@@ -313,4 +328,10 @@ class EntityWithGeneratedIndexName {
 
 		@Indexed(useGeneratedName = true, name = "ignored") String lastname;
 	}
+
+	@Document
+	class EntityWithPartialFilterIndex {
+
+		@Indexed(unique = true, name = "uniqueLastname", partialFilter = "{ \"lastname\" : { \"$exists\" : true } }") String lastname;
+	}
 }

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

@@ -30,6 +30,7 @@
  * 
  * @author Oliver Gierke
  * @author Laurent Canet
+ * @author Christian Schneider
  */
 public class IndexUnitTests {
 
@@ -69,6 +70,17 @@ public void testWithSparse() {
 		assertEquals("{ \"unique\" : true , \"sparse\" : true}", i.getIndexOptions().toString());
 	}
 
+	/**
+	 * @see DATAMONGO-1467
+	 */
+	@Test
+	public void testWithPartialFilter() {
+		Index i = new Index().on("name", Direction.ASC);
+		i.partialFilter("{ \"name\" : { \"$exists\" : true } }").unique();
+		assertEquals("{ \"name\" : 1}", i.getIndexKeys().toString());
+		assertEquals("{ \"unique\" : true , \"partialFilterExpression\" : { \"name\" : { \"$exists\" : true}}}", i.getIndexOptions().toString());
+	}
+
 	@Test
 	public void testGeospatialIndex() {
 		GeospatialIndex i = new GeospatialIndex("location").withMin(0);