Added #listAsync() to async result cursor

Method allows async retrieval of all records as list.

Author: lutovich

driver/src/main/java/org/neo4j/driver/internal/async/InternalStatementResultCursor.java

@@ -21,6 +21,7 @@
 import io.netty.util.concurrent.Future;
 import io.netty.util.concurrent.FutureListener;
 
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
@@ -87,6 +88,14 @@ public Response<Void> forEachAsync( final Consumer<Record> action )
         return result;
     }
 
+    @Override
+    public Response<List<Record>> listAsync()
+    {
+        InternalPromise<List<Record>> result = connection.newPromise();
+        internalListAsync( new ArrayList<Record>(), result );
+        return result;
+    }
+
     private void internalForEachAsync( final Consumer<Record> action, final InternalPromise<Void> result )
     {
         final InternalFuture<Record> recordFuture = internalNextAsync();
@@ -121,6 +130,40 @@ else if ( future.isSuccess() )
         } );
     }
 
+    private void internalListAsync( final List<Record> records, final InternalPromise<List<Record>> result )
+    {
+        final InternalFuture<Record> recordFuture = internalNextAsync();
+
+        recordFuture.addListener( new FutureListener<Record>()
+        {
+            @Override
+            public void operationComplete( Future<Record> future )
+            {
+                if ( future.isCancelled() )
+                {
+                    result.cancel( true );
+                }
+                else if ( future.isSuccess() )
+                {
+                    Record record = future.getNow();
+                    if ( record != null )
+                    {
+                        records.add( record );
+                        internalListAsync( records, result );
+                    }
+                    else
+                    {
+                        result.setSuccess( records );
+                    }
+                }
+                else
+                {
+                    result.setFailure( future.cause() );
+                }
+            }
+        } );
+    }
+
     private InternalFuture<Record> internalNextAsync()
     {
         if ( peekedRecordResponse != null )

driver/src/main/java/org/neo4j/driver/internal/handlers/PullAllResponseHandler.java

@@ -130,7 +130,6 @@ public synchronized InternalFuture<Record> nextAsync()
             if ( recordPromise == null )
             {
                 recordPromise = connection.newPromise();
-                System.out.println( "setting promise " + recordPromise.hashCode() );
             }
             return recordPromise;
         }

driver/src/main/java/org/neo4j/driver/v1/StatementResultCursor.java

@@ -39,4 +39,6 @@ public interface StatementResultCursor
     Response<Record> peekAsync();
 
     Response<Void> forEachAsync( Consumer<Record> action );
+
+    Response<List<Record>> listAsync();
 }

driver/src/test/java/org/neo4j/driver/v1/integration/SessionAsyncIT.java

@@ -28,6 +28,7 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.concurrent.Future;
@@ -490,6 +491,19 @@ public void shouldForEachWithNonEmptyCursor()
         testForEach( "UNWIND range(1, 10000) AS x RETURN x", 10000 );
     }
 
+    @Test
+    public void shouldConvertToListWithEmptyCursor()
+    {
+        testList( "MATCH (n:NoSuchLabel) RETURN n", Collections.emptyList() );
+    }
+
+    @Test
+    public void shouldConvertToListWithNonEmptyCursor()
+    {
+        testList( "UNWIND range(1, 100, 10) AS x RETURN x",
+                Arrays.asList( 1L, 11L, 21L, 31L, 41L, 51L, 61L, 71L, 81L, 91L ) );
+    }
+
     private Future<List<Future<Record>>> runNestedQueries( StatementResultCursor inputCursor )
     {
         Promise<List<Future<Record>>> resultPromise = GlobalEventExecutor.INSTANCE.newPromise();
@@ -576,6 +590,18 @@ public void accept( Record record )
         assertEquals( expectedSeenRecords, recordsSeen.get() );
     }
 
+    private <T> void testList( String query, List<T> expectedList )
+    {
+        StatementResultCursor cursor = await( session.runAsync( query ) );
+        List<Record> records = await( cursor.listAsync() );
+        List<Object> actualList = new ArrayList<>();
+        for ( Record record : records )
+        {
+            actualList.add( record.get( 0 ).asObject() );
+        }
+        assertEquals( expectedList, actualList );
+    }
+
     private static void assertSyntaxError( Exception e )
     {
         assertThat( e, instanceOf( ClientException.class ) );

driver/src/test/java/org/neo4j/driver/v1/integration/TransactionAsyncIT.java

@@ -23,7 +23,10 @@
 import org.junit.Rule;
 import org.junit.Test;
 
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -558,6 +561,18 @@ public void shouldForEachWithNonEmptyCursor()
         testForEach( "UNWIND range(1, 12555) AS x CREATE (n:Node {id: x}) RETURN n", 12555 );
     }
 
+    @Test
+    public void shouldConvertToListWithEmptyCursor()
+    {
+        testList( "CREATE (:Person)-[:KNOWS]->(:Person)", Collections.emptyList() );
+    }
+
+    @Test
+    public void shouldConvertToListWithNonEmptyCursor()
+    {
+        testList( "UNWIND [1, '1', 2, '2', 3, '3'] AS x RETURN x", Arrays.asList( 1L, "1", 2L, "2", 3L, "3" ) );
+    }
+
     private int countNodes( Object id )
     {
         StatementResult result = session.run( "MATCH (n:Node {id: $id}) RETURN count(n)", parameters( "id", id ) );
@@ -583,6 +598,19 @@ public void accept( Record record )
         assertEquals( expectedSeenRecords, recordsSeen.get() );
     }
 
+    private <T> void testList( String query, List<T> expectedList )
+    {
+        Transaction tx = await( session.beginTransactionAsync() );
+        StatementResultCursor cursor = await( tx.runAsync( query ) );
+        List<Record> records = await( cursor.listAsync() );
+        List<Object> actualList = new ArrayList<>();
+        for ( Record record : records )
+        {
+            actualList.add( record.get( 0 ).asObject() );
+        }
+        assertEquals( expectedList, actualList );
+    }
+
     private static void assertSyntaxError( Exception e )
     {
         assertThat( e, instanceOf( ClientException.class ) );