Log cursor results at debug level (#817)

* The logger name is "org.mongodb.driver.operation"
* The message is "Received batch of %s documents with cursorId %d from server %s"
* It logs the initial results and results from each getMore for both sync and reactive cursors

JAVA-4377

Author: jyemin

driver-core/src/main/com/mongodb/internal/connection/QueryResult.java

@@ -84,4 +84,8 @@ public List<T> getResults() {
     public ServerAddress getAddress() {
         return serverAddress;
     }
+
+    public long getCursorId() {
+        return cursorId;
+    }
 }

driver-core/src/main/com/mongodb/internal/operation/AsyncQueryBatchCursor.java

@@ -22,6 +22,8 @@
 import com.mongodb.ReadPreference;
 import com.mongodb.ServerCursor;
 import com.mongodb.connection.ServerType;
+import com.mongodb.diagnostics.logging.Logger;
+import com.mongodb.diagnostics.logging.Loggers;
 import com.mongodb.internal.async.AsyncAggregateResponseBatchCursor;
 import com.mongodb.internal.async.SingleResultCallback;
 import com.mongodb.internal.binding.AsyncConnectionSource;
@@ -49,13 +51,14 @@
 import static com.mongodb.assertions.Assertions.notNull;
 import static com.mongodb.internal.async.ErrorHandlingResultCallback.errorHandlingCallback;
 import static com.mongodb.internal.operation.CursorHelper.getNumberToReturn;
-import static com.mongodb.internal.operation.OperationHelper.LOGGER;
 import static com.mongodb.internal.operation.OperationHelper.getMoreCursorDocumentToQueryResult;
 import static com.mongodb.internal.operation.QueryHelper.translateCommandException;
 import static com.mongodb.internal.operation.ServerVersionHelper.serverIsAtLeastVersionThreeDotTwo;
+import static java.lang.String.format;
 import static java.util.Collections.singletonList;
 
 class AsyncQueryBatchCursor<T> implements AsyncAggregateResponseBatchCursor<T> {
+    private static final Logger LOGGER = Loggers.getLogger("operation");
     private static final FieldNameValidator NO_OP_FIELD_NAME_VALIDATOR = new NoOpFieldNameValidator();
     private static final String CURSOR = "cursor";
     private static final String POST_BATCH_RESUME_TOKEN = "postBatchResumeToken";
@@ -120,6 +123,7 @@ class AsyncQueryBatchCursor<T> implements AsyncAggregateResponseBatchCursor<T> {
             }
         }
         this.maxWireVersion = connection == null ? 0 : connection.getDescription().getMaxWireVersion();
+        logQueryResult(firstBatch);
     }
 
     /**
@@ -337,8 +341,10 @@ private void endOperationInProgress() {
         }
     }
 
+
     private void handleGetMoreQueryResult(final AsyncConnection connection, final SingleResultCallback<List<T>> callback,
                                           final QueryResult<T> result) {
+        logQueryResult(result);
         cursor.set(result.getCursor());
         if (isClosePending) {
             try {
@@ -373,6 +379,11 @@ private void handleGetMoreQueryResult(final AsyncConnection connection, final Si
         }
     }
 
+    private void logQueryResult(final QueryResult<T> result) {
+        LOGGER.debug(format("Received batch of %d documents with cursorId %d from server %s", result.getResults().size(),
+                result.getCursorId(), result.getAddress()));
+    }
+
     private class CommandResultSingleResultCallback implements SingleResultCallback<BsonDocument> {
         private final AsyncConnection connection;
         private final ServerCursor cursor;

driver-core/src/main/com/mongodb/internal/operation/QueryBatchCursor.java

@@ -27,6 +27,8 @@
 import com.mongodb.ServerCursor;
 import com.mongodb.annotations.ThreadSafe;
 import com.mongodb.connection.ServerType;
+import com.mongodb.diagnostics.logging.Logger;
+import com.mongodb.diagnostics.logging.Loggers;
 import com.mongodb.internal.binding.ConnectionSource;
 import com.mongodb.internal.connection.Connection;
 import com.mongodb.internal.connection.QueryResult;
@@ -60,9 +62,11 @@
 import static com.mongodb.internal.operation.OperationHelper.getMoreCursorDocumentToQueryResult;
 import static com.mongodb.internal.operation.QueryHelper.translateCommandException;
 import static com.mongodb.internal.operation.ServerVersionHelper.serverIsAtLeastVersionThreeDotTwo;
+import static java.lang.String.format;
 import static java.util.Collections.singletonList;
 
 class QueryBatchCursor<T> implements AggregateResponseBatchCursor<T> {
+    private static final Logger LOGGER = Loggers.getLogger("operation");
     private static final FieldNameValidator NO_OP_FIELD_NAME_VALIDATOR = new NoOpFieldNameValidator();
     private static final String CURSOR = "cursor";
     private static final String POST_BATCH_RESUME_TOKEN = "postBatchResumeToken";
@@ -318,6 +322,8 @@ private BsonDocument asGetMoreCommandDocument(final ServerCursor serverCursor) {
     private ServerCursor initFromQueryResult(final QueryResult<T> queryResult) {
         nextBatch = queryResult.getResults().isEmpty() ? null : queryResult.getResults();
         count += queryResult.getResults().size();
+        LOGGER.debug(format("Received batch of %d documents with cursorId %d from server %s", queryResult.getResults().size(),
+                queryResult.getCursorId(), queryResult.getAddress()));
         return queryResult.getCursor();
     }