DATAMONGO-1127 - Add support for geoNear queries with distance inform…

…ation.

We now support geoNear queries in Aggregations. Exposed GeoNearOperation factory method in Aggregation. Introduced new distanceField property to NearQuery since it is required for geoNear queries in Aggregations.

Original pull request: #261.

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

@@ -27,6 +27,7 @@
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
 import org.springframework.data.mongodb.core.aggregation.Fields.AggregationField;
 import org.springframework.data.mongodb.core.query.Criteria;
+import org.springframework.data.mongodb.core.query.NearQuery;
 import org.springframework.data.mongodb.core.query.SerializationUtils;
 import org.springframework.util.Assert;
 
@@ -291,6 +292,17 @@ public static Fields bind(String name, String target) {
 		return Fields.from(field(name, target));
 	}
 
+	/**
+	 * Creates a new {@link GeoNearOperation} instance from the given {@link NearQuery}.
+	 * 
+	 * @param query
+	 * @return
+	 * @since 1.7
+	 */
+	public static GeoNearOperation geoNear(NearQuery query) {
+		return new GeoNearOperation(query);
+	}
+
 	/**
 	 * Returns a new {@link AggregationOptions.Builder}.
 	 * 

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

@@ -32,6 +32,8 @@ public class GeoNearOperation implements AggregationOperation {
 	public GeoNearOperation(NearQuery nearQuery) {
 
 		Assert.notNull(nearQuery);
+		Assert.notNull(nearQuery.getDistanceField(), "distanceField must be configured in NearQuery.");
+
 		this.nearQuery = nearQuery;
 	}
 

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

@@ -44,6 +44,7 @@ public final class NearQuery {
 	private boolean spherical;
 	private Integer num;
 	private Integer skip;
+	private String distanceField;
 
 	/**
 	 * Creates a new {@link NearQuery}.
@@ -157,6 +158,21 @@ public NearQuery with(Pageable pageable) {
 		return this;
 	}
 
+	/**
+	 * Configures the name of the distanceField.
+	 * 
+	 * @param distanceField
+	 * @return
+	 */
+	public NearQuery withDistanceField(String distanceField) {
+
+		Assert.hasText(distanceField, "distanceField must not be empty.");
+
+		this.distanceField = distanceField;
+
+		return this;
+	}
+
 	/**
 	 * Sets the max distance results shall have from the configured origin. If a {@link Metric} was set before the given
 	 * value will be interpreted as being a value in that metric. E.g.
@@ -338,6 +354,13 @@ public Integer getSkip() {
 		return skip;
 	}
 
+	/**
+	 * @return the name of the distanceField.
+	 */
+	public String getDistanceField() {
+		return distanceField;
+	}
+
 	/**
 	 * Returns the {@link DBObject} built by the {@link NearQuery}.
 	 * 
@@ -367,6 +390,10 @@ public DBObject toDBObject() {
 
 		dbObject.put("spherical", spherical);
 
+		if (distanceField != null) {
+			dbObject.put("distanceField", distanceField);
+		}
+
 		return dbObject;
 	}
 }

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

@@ -47,11 +47,14 @@
 import org.springframework.dao.DataAccessException;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.domain.Sort.Direction;
+import org.springframework.data.geo.Metrics;
 import org.springframework.data.mapping.model.MappingException;
 import org.springframework.data.mongodb.core.CollectionCallback;
 import org.springframework.data.mongodb.core.MongoTemplate;
+import org.springframework.data.mongodb.core.Venue;
 import org.springframework.data.mongodb.core.aggregation.AggregationTests.CarDescriptor.Entry;
-import org.springframework.data.mongodb.core.mapping.Document;
+import org.springframework.data.mongodb.core.index.GeospatialIndex;
+import org.springframework.data.mongodb.core.query.NearQuery;
 import org.springframework.data.mongodb.core.query.Query;
 import org.springframework.data.mongodb.repository.Person;
 import org.springframework.data.util.Version;
@@ -1018,6 +1021,33 @@ public void shouldRetrieveDateTimeFragementsCorrectly() throws Exception {
 		assertThat(dbo.get("dayOfYearPlus1DayManually"), is((Object) dateTime.plusDays(1).getDayOfYear()));
 	}
 
+	/**
+	 * @see DATAMONGO-1127
+	 */
+	@Test
+	public void shouldSupportGeoNearQueriesForAggregation() {
+
+		mongoTemplate.dropCollection(Venue.class);
+
+		mongoTemplate.insert(new Venue("Penn Station", -73.99408, 40.75057));
+		mongoTemplate.insert(new Venue("10gen Office", -73.99171, 40.738868));
+		mongoTemplate.insert(new Venue("Flatiron Building", -73.988135, 40.741404));
+
+		mongoTemplate.indexOps(Venue.class).ensureIndex(new GeospatialIndex("location"));
+
+		NearQuery geoNear = NearQuery.near(-73, 40, Metrics.KILOMETERS).num(10).maxDistance(150)
+				.withDistanceField("distance");
+
+		Aggregation agg = newAggregation(Aggregation.geoNear(geoNear));
+		AggregationResults<DBObject> result = mongoTemplate.aggregate(agg, Venue.class, DBObject.class);
+
+		assertThat(result.getMappedResults(), hasSize(3));
+
+		DBObject firstResult = result.getMappedResults().get(0);
+		assertThat(firstResult.containsField("distance"), is(true));
+		assertThat(firstResult.get("distance"), is((Object) 117.620092203928));
+	}
+
 	private void assertLikeStats(LikeStats like, String id, long count) {
 
 		assertThat(like, is(notNullValue()));

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013 the original author or authors.
+ * Copyright 2013-2014 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.
@@ -28,13 +28,17 @@
  * Unit tests for {@link GeoNearOperation}.
  * 
  * @author Oliver Gierke
+ * @author Thomas Darimont
  */
 public class GeoNearOperationUnitTests {
 
+	/**
+	 * @see DATAMONGO-1127
+	 */
 	@Test
 	public void rendersNearQueryAsAggregationOperation() {
 
-		NearQuery query = NearQuery.near(10.0, 10.0);
+		NearQuery query = NearQuery.near(10.0, 10.0).withDistanceField("distance");
 		GeoNearOperation operation = new GeoNearOperation(query);
 		DBObject dbObject = operation.toDBObject(Aggregation.DEFAULT_CONTEXT);