DATAMONGO-1141 - Add support for $push $sort in Update.

Sorting update modifier added. Supports sorting arrays by document 
fields and element values.

Author: pavelvodrazka

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

@@ -27,6 +27,9 @@
 import java.util.Set;
 
 import org.springframework.dao.InvalidDataAccessApiUsageException;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.domain.Sort.Direction;
+import org.springframework.data.domain.Sort.Order;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -44,6 +47,7 @@
  * @author Thomas Darimont
  * @author Alexey Plotnik
  * @author Mark Paluch
+ * @author Pavel Vodrazka
  */
 public class Update {
 
@@ -660,6 +664,58 @@ public Object getValue() {
 			return this.count;
 		}
 	}
+	
+	/**
+	 * Implementation of {@link Modifier} representing {@code $sort}.
+	 *
+	 * @author Pavel Vodrazka
+	 * @since 1.10
+	 */
+	private static class SortModifier implements Modifier {
+
+		private final Object sort;
+
+		public SortModifier(Direction direction) {
+			this.sort = direction.isAscending() ? 1 : -1;
+		}
+
+		public SortModifier(Sort sort) {
+			this.sort = createDBObject(sort);
+		}
+
+		private DBObject createDBObject(Sort sort) {
+
+			DBObject obj = new BasicDBObject();
+
+			for (Order order : sort) {
+				if (order.isIgnoreCase()) {
+					throw new IllegalArgumentException(String.format("Given sort contained an Order for %s with ignore case! "
+							+ "MongoDB does not support sorting ignoring case currently!", order.getProperty()));
+				}
+				obj.put(order.getProperty(), order.isAscending() ? 1 : -1);
+			}
+
+			return obj;
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.data.mongodb.core.query.Update.Modifier#getKey()
+		 */
+		@Override
+		public String getKey() {
+			return "$sort";
+		}
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.data.mongodb.core.query.Update.Modifier#getValue()
+		 */
+		@Override
+		public Object getValue() {
+			return this.sort;
+		}		
+	}
 
 	/**
 	 * Builder for creating {@code $push} modifiers
@@ -707,6 +763,36 @@ public PushOperatorBuilder slice(int count) {
 			return this;
 		}
 
+		/**
+		 * Propagates {@code $sort} to {@code $push}. {@code $sort} requires the {@code $each} operator.
+		 * Forces elements to be sorted by values in given {@literal direction}.
+		 *
+		 * @param direction must not be {@literal null}.
+		 * @return never {@literal null}.
+		 * @since 1.10
+		 */
+		public PushOperatorBuilder sort(Direction direction) {
+
+			Assert.notNull(direction, "Direction must not be 'null'.");
+			this.modifiers.addModifier(new SortModifier(direction));
+			return this;
+		}
+
+		/**
+		 * Propagates {@code $sort} to {@code $push}. {@code $sort} requires the {@code $each} operator.
+		 * Forces document elements to be sorted in given {@literal order}.
+		 *
+		 * @param order must not be {@literal null}.
+		 * @return never {@literal null}.
+		 * @since 1.10
+		 */
+		public PushOperatorBuilder sort(Sort order) {
+
+			Assert.notNull(order, "Order must not be 'null'.");
+			this.modifiers.addModifier(new SortModifier(order));
+			return this;
+		}
+
 		/**
 		 * Forces values to be added at the given {@literal position}.
 		 *

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

@@ -16,6 +16,7 @@
 package org.springframework.data.mongodb.core.convert;
 
 import static org.hamcrest.CoreMatchers.*;
+import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.collection.IsMapContaining.*;
 import static org.junit.Assert.*;
 import static org.mockito.Mockito.*;
@@ -42,6 +43,9 @@
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.convert.WritingConverter;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.domain.Sort.Direction;
+import org.springframework.data.domain.Sort.Order;
 import org.springframework.data.mapping.model.MappingException;
 import org.springframework.data.mongodb.MongoDbFactory;
 import org.springframework.data.mongodb.core.DBObjectTestUtils;
@@ -68,6 +72,7 @@
  * @author Christoph Strobl
  * @author Thomas Darimont
  * @author Mark Paluch
+ * @author Pavel Vodrazka
  */
 @RunWith(MockitoJUnitRunner.class)
 public class UpdateMapperUnitTests {
@@ -416,6 +421,68 @@ public void updatePushEachWithSliceShouldRenderWhenUsingMultiplePushCorrectly()
 		assertThat(key2.containsField("$each"), is(true));
 	}
 
+	/**
+	 * @see DATAMONGO-1141
+	 */
+	@Test
+	public void updatePushEachWithValueSortShouldRenderCorrectly() {
+
+		Update update = new Update().push("scores").sort(Direction.DESC).each(42, 23, 68);
+
+		DBObject mappedObject = mapper.getMappedObject(update.getUpdateObject(), context.getPersistentEntity(Object.class));
+
+		DBObject push = getAsDBObject(mappedObject, "$push");
+		DBObject key = getAsDBObject(push, "scores");
+
+		assertThat(key.containsField("$sort"), is(true));
+		assertThat((Integer) key.get("$sort"), is(-1));
+		assertThat(key.containsField("$each"), is(true));
+	}
+
+	/**
+	 * @see DATAMONGO-1141
+	 */
+	@Test
+	public void updatePushEachWithDocumentSortShouldRenderCorrectly() {
+
+		Update update = new Update().push("names").sort(new Sort(new Order(Direction.ASC, "last"), new Order(Direction.ASC, "first")))
+				.each(Collections.emptyList());
+
+		DBObject mappedObject = mapper.getMappedObject(update.getUpdateObject(), context.getPersistentEntity(Object.class));
+
+		DBObject push = getAsDBObject(mappedObject, "$push");
+		DBObject key = getAsDBObject(push, "names");
+
+		assertThat(key.containsField("$sort"), is(true));
+		assertThat((DBObject) key.get("$sort"), equalTo(new BasicDBObjectBuilder().add("last", 1).add("first", 1).get()));
+		assertThat(key.containsField("$each"), is(true));
+	}
+
+	/**
+	 * @see DATAMONGO-1141
+	 */
+	@Test
+	public void updatePushEachWithSortShouldRenderCorrectlyWhenUsingMultiplePush() {
+
+		Update update = new Update().push("authors").sort(Direction.ASC).each("Harry")
+				.push("chapters").sort(new Sort(Direction.ASC, "order")).each(Collections.emptyList());
+
+		DBObject mappedObject = mapper.getMappedObject(update.getUpdateObject(), context.getPersistentEntity(Object.class));
+
+		DBObject push = getAsDBObject(mappedObject, "$push");
+		DBObject key1 = getAsDBObject(push, "authors");
+
+		assertThat(key1.containsField("$sort"), is(true));
+		assertThat((Integer) key1.get("$sort"), is(1));
+		assertThat(key1.containsField("$each"), is(true));
+
+		DBObject key2 = getAsDBObject(push, "chapters");
+
+		assertThat(key2.containsField("$sort"), is(true));
+		assertThat((DBObject) key2.get("$sort"), equalTo(new BasicDBObjectBuilder().add("order", 1).get()));
+		assertThat(key2.containsField("$each"), is(true));
+	}
+
 	/**
 	 * @see DATAMONGO-410
 	 */