Github user ss77892 commented on a diff in the pull request:
https://github.com/apache/incubator-ratis/pull/4#discussion_r212197492
--- Diff:
ratis-logservice/src/main/java/org/apache/ratis/logservice/api/LogReader.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.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+
+/**
+ * Synchronous client interface to read from a LogStream.
+ */
+public interface LogReader extends AutoCloseable {
+
+ /**
+ * Seeks to the position before the record at the provided {@code
offset} in the LogStream.
+ *
+ * @param offset A non-negative, offset in the LogStream
+ * @return A future for when the operation is completed.
+ */
+ void seek(long recordId) throws IOException;
--- End diff --
That's why most of the implementations of distributed logs (pub/sub model)
actually are using segments/slices/whatever they call it and why usually they
are relatively small. Usually, there is a separate index that maintains the map
between id and segment OR it keeps start id for the segment in its name. What
do you mean by 'separate logs from message queues'?
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