hadoop/hadoop-hdfs-project/hadoop-hdfs/src/main/proto/JournalProtocol.proto

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4.0 KiB
Protocol Buffer

/**
* 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.
*/
/**
* These .proto interfaces are private and stable.
* Please see http://wiki.apache.org/hadoop/Compatibility
* for what changes are allowed for a *stable* .proto interface.
*/
// This file contains protocol buffers that are used throughout HDFS -- i.e.
// by the client, server, and data transfer protocols.
syntax = "proto2";
option java_package = "org.apache.hadoop.hdfs.protocol.proto";
option java_outer_classname = "JournalProtocolProtos";
option java_generic_services = true;
option java_generate_equals_and_hash = true;
package hadoop.hdfs;
import "hdfs.proto";
import "HdfsServer.proto";
/**
* Journal information used by the journal receiver to identify a journal.
*/
message JournalInfoProto {
required string clusterID = 1; // ID of the cluster
optional uint32 layoutVersion = 2; // Layout version
optional uint32 namespaceID = 3; // Namespace ID
}
/**
* journalInfo - the information about the journal
* firstTxnId - the first txid in the journal records
* numTxns - Number of transactions in editlog
* records - bytes containing serialized journal records
* epoch - change to this represents change of journal writer
*/
message JournalRequestProto {
required JournalInfoProto journalInfo = 1;
required uint64 firstTxnId = 2;
required uint32 numTxns = 3;
required bytes records = 4;
required uint64 epoch = 5;
}
/**
* void response
*/
message JournalResponseProto {
}
/**
* journalInfo - the information about the journal
* txid - first txid in the new log
*/
message StartLogSegmentRequestProto {
required JournalInfoProto journalInfo = 1; // Info about the journal
required uint64 txid = 2; // Transaction ID
required uint64 epoch = 3;
}
/**
* void response
*/
message StartLogSegmentResponseProto {
}
/**
* journalInfo - the information about the journal
* txid - first txid in the new log
*/
message FenceRequestProto {
required JournalInfoProto journalInfo = 1; // Info about the journal
required uint64 epoch = 2; // Epoch - change indicates change in writer
optional string fencerInfo = 3; // Info about fencer for debugging
}
/**
* previousEpoch - previous epoch if any or zero
* lastTransactionId - last valid transaction Id in the journal
* inSync - if all journal segments are available and in sync
*/
message FenceResponseProto {
optional uint64 previousEpoch = 1;
optional uint64 lastTransactionId = 2;
optional bool inSync = 3;
}
/**
* Protocol used to journal edits to a remote node. Currently,
* this is used to publish edits from the NameNode to a BackupNode.
*
* See the request and response for details of rpc call.
*/
service JournalProtocolService {
/**
* Request sent by active namenode to backup node via
* EditLogBackupOutputStream to stream editlog records.
*/
rpc journal(JournalRequestProto) returns (JournalResponseProto);
/**
* Request sent by active namenode to backup node to notify
* that the NameNode has rolled its edit logs and is now writing a
* new log segment.
*/
rpc startLogSegment(StartLogSegmentRequestProto)
returns (StartLogSegmentResponseProto);
/**
* Request to fence a journal receiver.
*/
rpc fence(FenceRequestProto)
returns (FenceResponseProto);
}