Github user liuml07 commented on a diff in the pull request:
https://github.com/apache/incubator-ratis/pull/4#discussion_r214449799
--- Diff:
ratis-logservice/src/main/java/org/apache/ratis/logservice/api/LogWriter.java
---
@@ -0,0 +1,59 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.ratis.logservice.api;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+
+/**
+ * Synchronous client interface to write to a LogStream.
+ */
+public interface LogWriter extends AutoCloseable {
+
+ /**
+ * Appends the given data as a record in the LogStream.
+ *
+ * @param data The record to append
+ * @return The recordId for the record just written
+ */
+ long write(ByteBuffer data) throws IOException;
+
+ /**
+ * Appends each entry of data as a new record in the LogStream. If this
method returns
+ * successfully, all records can be considered persisted. Otherwise,
none can be assumed
+ * to have been written.
+ *
+ * @param records Records to append
+ * @return The largest recordId assigned to the records written
+ */
+ long writeMany(List<ByteBuffer> records) throws IOException;
--- End diff --
Yes. I assume we don't provide any transaction support, i.e. if one record
writing fails, previous written record in the batch will have no guarantee
(succeeded or reverted).
---
