Github user ss77892 commented on a diff in the pull request:
https://github.com/apache/incubator-ratis/pull/4#discussion_r212202468
--- Diff:
ratis-logservice/src/main/java/org/apache/ratis/logservice/api/LogService.java
---
@@ -0,0 +1,53 @@
+/**
+ * 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.util.Iterator;
+import java.util.concurrent.CompletableFuture;
+
+/**
+ * Entry point for interacting with the Ratis LogService.
+ */
+public interface LogService {
+
+ /**
+ * Creates a new {@link LogStream} identified by the given name. Throws
+ * an exception if a {@link LogStream} with the given name already
exists.
+ *
+ * @param name Unique name for this LogStream.
+ */
+ CompletableFuture<LogStream> createLog(LogName name);
+
+ /**
+ * Fetches the {@link LogStream} identified by the given name.
+ *
+ * @param name The name of the LogStream
+ */
+ CompletableFuture<LogStream> getLog(LogName name);
+
+ /**
+ * Lists all {@link LogStream} instances known by this LogService.
+ */
+ CompletableFuture<Iterator<LogStream>> listLogs();
--- End diff --
I would better ask whether this method should be here. Ratis is an embedded
library that allows creating a SINGLE distributed state machine. That means a
SINGLE log. A distributed log service that would allow creating a number of
logs (i.e. state machines) sounds like an application that would include state
machines creation/management. That still can be a part of the embedded library,
but it would make everything more complicated and less flexible (i.e. different
use cases may require special rules for quorum members like rack awareness,
latency measurement, RS Groups in case of HBase, etc).
---
