QueryDSL Sorting Support

src/main/java/com/querydsl/couchbase/document/CouchbaseDocumentSerializer.java

@@ -39,11 +39,13 @@
 import com.querydsl.core.types.SubQueryExpression;
 import com.querydsl.core.types.TemplateExpression;
 import com.querydsl.core.types.Visitor;
+import com.querydsl.core.types.Order;
 
 /**
  * Serializes the given Querydsl query to a Document query for Couchbase.
  *
  * @author Michael Reiche
+ * @author Tigran Babloyan
  */
 public abstract class CouchbaseDocumentSerializer implements Visitor<Object, Void> {
 
@@ -55,8 +57,15 @@ public Sort toSort(List<OrderSpecifier<?>> orderBys) {
 		Sort sort = Sort.unsorted();
 		for (OrderSpecifier<?> orderBy : orderBys) {
 			Object key = orderBy.getTarget().accept(this, null);
-			// sort.and(Sort.by(orderBy));
-			// sort.append(key.toString(), orderBy.getOrder() == Order.ASC ? 1 : -1);
+			String keyAsString = key.toString();
+			Sort.NullHandling sortNullHandling = switch (orderBy.getNullHandling()) {
+				case NullsFirst -> Sort.NullHandling.NULLS_FIRST;
+				case NullsLast -> Sort.NullHandling.NULLS_LAST;
+				default -> Sort.NullHandling.NATIVE;
+			};
+			Sort.Direction sortDirection = orderBy.getOrder() == Order.ASC ? Sort.Direction.ASC : Sort.Direction.DESC;
+			Sort.Order sortOrder = new Sort.Order(sortDirection, keyAsString, sortNullHandling);
+			sort = sort.and(Sort.by(sortOrder));
 		}
 		return sort;
 	}

src/main/java/org/springframework/data/couchbase/repository/support/BasicQuery.java

@@ -30,6 +30,7 @@
  * BasicQuery for Querydsl
  *
  * @author Michael Reiche
+ * @author Tigran Babloyan
  */
 public class BasicQuery extends Query {
 
@@ -40,12 +41,11 @@ public class BasicQuery extends Query {
 	 * {@link CouchbaseDocument}.
 	 *
 	 * @param query must not be {@literal null}.
-	 * @param projectionFields must not be {@literal null}.
+	 * @param projectionFields can be {@literal null}.
 	 * @throws IllegalArgumentException when {@code sortObject} or {@code fieldsObject} is {@literal null}.
 	 */
 	public BasicQuery(Query query, Map<String, String> projectionFields) {
 		super(query);
-		Assert.notNull(projectionFields, "Field document must not be null");
 		this.projectionFields = projectionFields;
 	}
 

src/main/java/org/springframework/data/couchbase/repository/support/SpringDataCouchbaseQuery.java

@@ -26,6 +26,7 @@
 
 import org.springframework.data.couchbase.core.CouchbaseOperations;
 import org.springframework.data.couchbase.core.ExecutableFindByQueryOperation;
+import org.springframework.data.couchbase.core.query.Query;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.Pageable;
@@ -250,7 +251,7 @@ protected org.springframework.data.couchbase.core.query.Query createQuery(@Nulla
 			@Nullable Expression<?> projection, QueryModifiers modifiers, List<OrderSpecifier<?>> orderBy) {
 
 		Map<String, String> fields = createProjection(projection);
-		BasicQuery basicQuery = new BasicQuery(createCriteria(filter), fields);
+		BasicQuery basicQuery = filter == null ? new BasicQuery(new Query(), fields) : new BasicQuery(createCriteria(filter), fields);
 
 		Integer limit = modifiers.getLimitAsInteger();
 		Integer offset = modifiers.getOffsetAsInteger();

src/main/java/org/springframework/data/couchbase/repository/support/SpringDataCouchbaseQuerySupport.java

@@ -29,6 +29,7 @@
 
 /**
  * @author Michael Reiche
+ * @author Tigran Babloyan
  */
 abstract class SpringDataCouchbaseQuerySupport<Q extends SpringDataCouchbaseQuerySupport<Q>>
 		extends AbstractCouchbaseQueryDSL<Q> {
@@ -84,10 +85,9 @@ public String toString() {
 		// sb.append(", ").append(projection.toJson(JSON_WRITER_SETTINGS, codec));
 		// }
 		sb.append(")");
-		// TODO
-		// if (!sort.isEmpty()) {
-		// sb.append(".sort(").append(sort.toJson(JSON_WRITER_SETTINGS, codec)).append(")");
-		// }
+		if (!sort.isEmpty()) {
+			sb.append(".sort(").append(sort).append(")");
+		}
 		if (getQueryMixin().getMetadata().getModifiers().getOffset() != null) {
 			sb.append(".skip(").append(getQueryMixin().getMetadata().getModifiers().getOffset()).append(")");
 		}
@@ -128,6 +128,6 @@ public CouchbaseDocument asDocument() {
 	 *         CouchbaseDocumentSerializer#toSort(List)
 	 */
 	protected Sort createSort(List<OrderSpecifier<?>> orderSpecifiers) {
-		return null; // TODO serializer.toSort(orderSpecifiers);
+		return serializer.toSort(orderSpecifiers);
 	}
 }

src/test/java/org/springframework/data/couchbase/repository/query/CouchbaseRepositoryQuerydslIntegrationTests.java

@@ -19,12 +19,15 @@
 import static com.couchbase.client.java.query.QueryScanConsistency.REQUEST_PLUS;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
 import static org.springframework.data.couchbase.util.Util.comprises;
 import static org.springframework.data.couchbase.util.Util.exactly;
 
 import java.util.Arrays;
+import java.util.Comparator;
 import java.util.Locale;
 import java.util.Optional;
+import java.util.stream.StreamSupport;
 
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
@@ -53,6 +56,7 @@
 import org.springframework.data.couchbase.util.ClusterType;
 import org.springframework.data.couchbase.util.IgnoreWhen;
 import org.springframework.data.couchbase.util.JavaIntegrationTests;
+import org.springframework.data.domain.Sort;
 import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
 import org.springframework.validation.beanvalidation.LocalValidatorFactoryBean;
 
@@ -67,6 +71,7 @@
  * Repository tests
  *
  * @author Michael Reiche
+ * @author Tigran Babloyan
  */
 @SpringJUnitConfig(CouchbaseRepositoryQuerydslIntegrationTests.Config.class)
 @IgnoreWhen(missesCapabilities = Capabilities.QUERY, clusterTypes = ClusterType.MOCKED)
@@ -410,6 +415,72 @@ void testIn() {
 			assertEquals(" WHERE name in $1", bq(predicate));
 		}
 	}
+
+	@Test
+	void testSort(){
+		{
+			BooleanExpression predicate = airline.name.in(Arrays.stream(saved).map(Airline::getName).toList());
+			Iterable<Airline> result = airlineRepository.findAll(predicate, Sort.by("name").ascending());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+							Arrays.stream(saved)
+									.sorted(Comparator.comparing(Airline::getName))
+									.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+
+		{
+			BooleanExpression predicate = airline.name.in(Arrays.stream(saved).map(Airline::getName).toList());
+			Iterable<Airline> result = airlineRepository.findAll(predicate, Sort.by("name").descending());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+							Arrays.stream(saved)
+									.sorted(Comparator.comparing(Airline::getName).reversed())
+									.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+
+		{
+			BooleanExpression predicate = airline.name.in(Arrays.stream(saved).map(Airline::getName).toList());
+			Iterable<Airline> result = airlineRepository.findAll(predicate, airline.name.asc());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+							Arrays.stream(saved)
+									.sorted(Comparator.comparing(Airline::getName))
+									.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+
+		{
+			BooleanExpression predicate = airline.name.in(Arrays.stream(saved).map(Airline::getName).toList());
+			Iterable<Airline> result = airlineRepository.findAll(predicate, airline.name.desc());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+							Arrays.stream(saved)
+									.sorted(Comparator.comparing(Airline::getName).reversed())
+									.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+
+		{
+			Comparator<String> nullSafeStringComparator = Comparator
+					.nullsFirst(String::compareTo);
+			Iterable<Airline> result = airlineRepository.findAll(airline.hqCountry.asc().nullsFirst());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+					Arrays.stream(saved)
+							.sorted(Comparator.comparing(Airline::getHqCountry, nullSafeStringComparator))
+							.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+
+		{
+			Comparator<String> nullSafeStringComparator = Comparator
+					.nullsFirst(String::compareTo);
+			Iterable<Airline> result = airlineRepository.findAll(airline.hqCountry.desc().nullsLast());
+			assertArrayEquals(StreamSupport.stream(result.spliterator(), false).toArray(Airline[]::new),
+					Arrays.stream(saved)
+							.sorted(Comparator.comparing(Airline::getHqCountry, nullSafeStringComparator).reversed())
+							.toArray(Airline[]::new),
+					"Order of airlines does not match");
+		}
+	}
+
 
 	@Test
 	void testNotIn() {