/**
 * 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 unstable.
 * Please see http://wiki.apache.org/hadoop/Compatibility
 * for what changes are allowed for a *unstable* .proto interface.
 */

option java_package = "org.apache.hadoop.cblock.protocol.proto";
option java_outer_classname = "CBlockServiceProtocolProtos";
option java_generic_services = true;
option java_generate_equals_and_hash = true;
package hadoop.cblock;

/**
* This message is sent to CBlock server to create a volume. Creating
* volume requries four parameters: owner of the volume, name of the volume
* size of volume and block size of the volume.
*/
message CreateVolumeRequestProto {
    required string userName = 1;
    required string volumeName = 2;
    required uint64 volumeSize = 3;
    optional uint32 blockSize = 4 [default = 4096];
}

/**
* Empty response message.
*/
message CreateVolumeResponseProto {

}

/**
* This message is sent to CBlock server to delete a volume. The volume
* is specified by owner name and volume name. If force is set to
* false, volume will be deleted only if it is empty. Otherwise delete it
* regardless.
*/
message DeleteVolumeRequestProto {
    required string userName = 1;
    required string volumeName = 2;
    optional bool force = 3;
}

/**
* Empty response message.
*/
message DeleteVolumeResponseProto {

}

/**
* This message is sent to CBlock server to request info of a volume. The
* volume is specified by owner name and volume name.
*/
message InfoVolumeRequestProto {
    required string userName = 1;
    required string volumeName = 2;
}

/**
* This message describes the information of a volume.
* Currently, the info includes the volume creation parameters and a number
* as the usage of the volume, in terms of number of bytes.
*/
message VolumeInfoProto {
    required string userName = 1;
    required string volumeName = 2;
    required uint64 volumeSize = 3;
    required uint64 blockSize = 4;
    optional uint64 usage = 5;
    // TODO : potentially volume ACL
}

/**
* This message is sent from CBlock server as response of info volume request.
*/
message InfoVolumeResponseProto {
    optional VolumeInfoProto volumeInfo = 1;
}

/**
* This message is sent to CBlock server to list all available volume.
*/
message ListVolumeRequestProto {
    optional string userName = 1;
}

/**
* This message is sent from CBlock server as response of volume listing.
*/
message ListVolumeResponseProto {
    repeated VolumeInfoProto volumeEntry = 1;
}

service CBlockServiceProtocolService {
    /**
    * Create a volume.
    */
    rpc createVolume(CreateVolumeRequestProto) returns(CreateVolumeResponseProto);

    /**
    * Delete a volume.
    */
    rpc deleteVolume(DeleteVolumeRequestProto) returns(DeleteVolumeResponseProto);

    /**
    * Get info of a volume.
    */
    rpc infoVolume(InfoVolumeRequestProto) returns(InfoVolumeResponseProto);

    /**
    * List all available volumes.
    */
    rpc listVolume(ListVolumeRequestProto) returns(ListVolumeResponseProto);
}