/**
* Perform a given file operation based on the operationId, which will be used to retrieve the
* operation details from the CurrentOperations class
*/
public void requestFileOperation(Long operationId) throws Exception {
Operation operation = CurrentOperations.getOperation(operationId);
switch (operation.getOperationType()) {
case OperationType.FILE_OP_LS:
ls(operation);
break;
case OperationType.FILE_OP_WRITE:
writeFile(operation);
break;
case OperationType.FILE_OP_READ:
readFile(operation);
break;
}
}
private void writeFile(Operation operation) throws Exception {
Logger.logDebug("Start operation to send writeFile request to datanode", getClass());
// on a write request, the parameter is a FileWriteOperationParameter
FileWriteOperationParameter fileWriteParm =
(FileWriteOperationParameter) operation.getParamProto();
// find all datanodes that will be receiving that file
List<DatanodeInfo> datanodes = Datanodes.findDatanodesForFileWrite(fileWriteParm.getDfsFile());
Logger.logDebug(
"Operation will send write request to " + datanodes.size() + " datanodes: ", getClass());
// add the chosen datanodes to the operation parameter
for (DatanodeInfo datanodeInfo : datanodes) {
fileWriteParm.addDatanode(datanodeInfo);
Logger.logDebug(">>> " + datanodeInfo, getClass());
}
// remove valid datanodes from the dfsFile
FileStructure.getInstance()
.removeValidDatanodes(fileWriteParm.getFilePath(), fileWriteParm.getDfsFile().getName());
// send the request to the first datanode
FileOperationReqProtocol fileOperationRequest =
new FileOperationReqProtocolImpl(fileWriteParm.findNextDatanode(), operation);
fileOperationRequest.requestFileOperation();
}
/** *********** OLD STUFF ********** */
@Deprecated
private void ls(Operation operation) throws Exception {
// on an ls request, the parameter is a FilePathProto
FilePathProto path = (FilePathProto) operation.getParamProto();
// get the possible datanodes ids we can ls from
FileStructureOperation fileStructureOperation = new FileStructureOperationImpl();
List<String> validDatanodesIds = fileStructureOperation.ls(path.getPath());
// figure the preferred datanode
// DatanodeInfo datanode = Datanodes.findPreferredDatanode(validDatanodesIds);
// DatanodeInfo datanode = Datanodes.findPreferredDatanode(null);
DatanodeInfo datanode = new DatanodeInfo("datanode1", "127.0.0.1", 30000);
// send the request to the datanode
FileOperationReqProtocol fileOperationRequest =
new FileOperationReqProtocolImpl(datanode, operation);
fileOperationRequest.requestFileOperation();
}
private void readFile(Operation operation) throws Exception {
Logger.logDebug("Start operation to send readFile request to datanode", getClass());
// on a read request, the parameter is a FileReadOperationParameter
FileReadOperationParameter fileReadParm =
(FileReadOperationParameter) operation.getParamProto();
// find the datanode that will be sending that file
List<DatanodeInfo> datanodes = Datanodes.findDatanodesForFileWrite(fileReadParm.getDfsFile());
Logger.logDebug("Operation will send read request to one of the valid datanodes: ", getClass());
// add the chosen datanodes to the operation parameter
for (DatanodeInfo datanodeInfo : datanodes) {
fileReadParm.addDatanode(datanodeInfo);
Logger.logDebug(">>> " + datanodeInfo, getClass());
}
// TODO receive file from multiple datanodes, someday
// send the request to the first datanode
FileOperationReqProtocol fileOperationRequest =
new FileOperationReqProtocolImpl(fileReadParm.findNextDatanode(), operation);
fileOperationRequest.requestFileOperation();
}