public static NodeAddress lookupNode(byte[] id, NodeAddress seedNodeAddress, int serverPort)
throws Exception {
// start up a server socket to accept the connection
ServerSocket serverSocket = new ServerSocket(serverPort);
// send store data message to random node
LookupNodeMsg lookupNodeMsg =
new LookupNodeMsg(id, new NodeAddress("StoreData", null, serverPort), 0);
lookupNodeMsg.addHop(seedNodeAddress);
Socket seedSocket = new Socket(seedNodeAddress.getInetAddress(), seedNodeAddress.getPort());
ObjectOutputStream seedOut = new ObjectOutputStream(seedSocket.getOutputStream());
seedOut.writeObject(lookupNodeMsg);
seedSocket.close();
LOGGER.info(
"Sent lookup node message with id '"
+ HexConverter.convertBytesToHex(id)
+ "' to node "
+ seedNodeAddress);
// receive connection on server socket from node where data should reside
Socket nodeSocket = serverSocket.accept();
Message replyMsg = (Message) new ObjectInputStream(nodeSocket.getInputStream()).readObject();
// ensure we get a node info message
if (replyMsg.getMsgType() == Message.ERROR_MSG) {
throw new Exception(((ErrorMsg) replyMsg).getMsg());
} else if (replyMsg.getMsgType() != Message.NODE_INFO_MSG) {
throw new Exception("Recieved an unexpected message type '" + replyMsg.getMsgType() + "'.");
}
// parse reply message
NodeInfoMsg nodeInfoMsg = (NodeInfoMsg) replyMsg;
if (nodeInfoMsg.getNodeAddress().getInetAddress() == null) {
nodeInfoMsg.getNodeAddress().setInetAddress(nodeSocket.getInetAddress());
}
serverSocket.close();
nodeSocket.close();
return nodeInfoMsg.getNodeAddress();
}
public static void main(String[] args) {
int port = 0;
String discoveryNodeAddr = null;
int discoveryNodePort = 0;
try {
port = Integer.parseInt(args[0]);
discoveryNodeAddr = args[1];
discoveryNodePort = Integer.parseInt(args[2]);
} catch (Exception e) {
System.out.println("Usage: Client port controllerHosName controllerPort");
System.exit(1);
}
String input = "";
Scanner scanner = new Scanner(System.in);
while (true) {
try {
System.out.print("Options\nS) Store File\nR) Retrieve File\nQ) Quit\nInput:");
input = scanner.nextLine();
if (input.equalsIgnoreCase("Q")) {
break;
} else if (!input.equalsIgnoreCase("S") && !input.equalsIgnoreCase("R")) {
LOGGER.severe("Unknown input. Please reenter.");
continue;
}
// read in the filename
byte[] id = null;
System.out.print("\tFilename:");
File file = new File(scanner.nextLine());
// read in id
System.out.print("\tID (leave blank to auto generate one):");
String idStr = scanner.nextLine();
if (!idStr.equals("")) {
id = HexConverter.convertHexToBytes(idStr);
} else {
short idValue = (short) (file.getName().hashCode() % (int) Short.MAX_VALUE);
id = new byte[2];
id[0] = (byte) (idValue & 0xff);
id[1] = (byte) ((idValue >> 8) & 0xff);
}
// get random node
NodeAddress seedNodeAddress = getRandomNode(discoveryNodeAddr, discoveryNodePort);
// lookup id in cluster
NodeAddress nodeAddress = lookupNode(id, seedNodeAddress, port);
if (input.equalsIgnoreCase("S")) {
if (!file.exists()) {
throw new Exception("File '" + file.getName() + "' does not exist.");
}
// read data into buffer
FileInputStream in = new FileInputStream(file);
byte[] data = new byte[(int) file.length()];
if (in.read(data) != data.length) {
LOGGER.severe("Error reading data into buffer.");
return;
}
in.close();
// write data to the node
WriteDataMsg writeDataMsg = new WriteDataMsg(id, data);
Socket socket = new Socket(nodeAddress.getInetAddress(), nodeAddress.getPort());
ObjectOutputStream out = new ObjectOutputStream(socket.getOutputStream());
out.writeObject(writeDataMsg);
socket.close();
LOGGER.info(
"Sent data with id '"
+ HexConverter.convertBytesToHex(id)
+ "' to node "
+ nodeAddress
+ ".");
} else if (input.equalsIgnoreCase("R")) {
// read in storage directory
System.out.print("\tStorage Directory:");
file = new File(scanner.nextLine() + File.separator + file.getName());
file.getParentFile().mkdirs();
// request file from node
ReadDataMsg readDataMsg = new ReadDataMsg(id);
Socket socket = new Socket(nodeAddress.getInetAddress(), nodeAddress.getPort());
ObjectOutputStream socketOut = new ObjectOutputStream(socket.getOutputStream());
socketOut.writeObject(readDataMsg);
// parse reply message
Message replyMsg = (Message) new ObjectInputStream(socket.getInputStream()).readObject();
socket.close();
if (replyMsg.getMsgType() == Message.ERROR_MSG) {
throw new Exception(((ErrorMsg) replyMsg).getMsg());
} else if (replyMsg.getMsgType() != Message.WRITE_DATA_MSG) {
throw new Exception(
"Recieved an unexpected message type '" + replyMsg.getMsgType() + "'.");
}
WriteDataMsg writeDataMsg = (WriteDataMsg) replyMsg;
// write file contents
FileOutputStream out = new FileOutputStream(file);
for (byte b : writeDataMsg.getData()) {
out.write(b);
}
out.close();
LOGGER.info("Wrote data to file '" + file.getCanonicalPath() + "'.");
} else if (!input.equalsIgnoreCase("Q")) {
LOGGER.severe("Unknown input. Please reenter.");
}
} catch (Exception e) {
e.printStackTrace();
LOGGER.severe(e.getMessage());
}
}
}