Projet_JAVA_P2P_STRI2A/src/serverP2P/ServerManagementUDP.java
2020-03-04 22:29:54 +01:00

249 lines
8.2 KiB
Java

package serverP2P;
import java.util.Vector;
import java.io.File;
import java.io.IOException;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.nio.file.Paths;
import java.nio.file.Files;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import protocolP2P.ProtocolP2PPacketUDP;
import protocolP2P.ProtocolP2PPacket;
import protocolP2P.RequestResponseCode;
import protocolP2P.Payload;
import protocolP2P.LoadRequest;
import protocolP2P.FileList;
import protocolP2P.FilePart;
import exception.InternalError;
import exception.ProtocolError;
import exception.SizeError;
import exception.TransmissionError;
import exception.VersionError;
import exception.SocketClosed;
import remoteException.EmptyDirectory;
import remoteException.InternalRemoteError;
import remoteException.NotFound;
import remoteException.ProtocolRemoteError;
import remoteException.VersionRemoteError;
import remoteException.EmptyFile;
import java.util.Arrays;
import tools.Logger;
import tools.LogLevel;
import java.util.HashMap;
import java.util.Map;
import protocolP2P.HashAlgorithm;
import protocolP2P.HashRequest;
import protocolP2P.HashResponse;
/** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol for UDP.
* @author Louis Royer
* @author Flavien Haas
* @author JS Auge
* @version 1.0
*/
public class ServerManagementUDP implements Runnable {
private String[] fileList;
private Map<String, byte[]> sha512 = new HashMap<>();
private String baseDirectory;
private int UDPPort;
private DatagramSocket socket;
private Logger logger;
/** Constructor for UDP implementation, with baseDirectory and UDPPort parameters.
* @param baseDirectory the root directory where files are stored
* @param UDPPort the server will listen on this port
*/
public ServerManagementUDP(String baseDirectory, int UDPPort, Logger logger) {
this.logger = logger;
this.baseDirectory = baseDirectory;
this.UDPPort = UDPPort;
initFileList();
initSha512();
try {
socket = new DatagramSocket(UDPPort);
} catch (SocketException e) {
logger.writeUDP("Error: cannot listen on port " + UDPPort, LogLevel.Error);
System.exit(-1);
}
}
/** Implementation of runnable. This methods allows to run the server.
*/
public void run() {
logger.writeUDP("Server sucessfully started", LogLevel.Info);
while(true) {
try {
ProtocolP2PPacketUDP pd = new ProtocolP2PPacketUDP((Object)socket);
Payload p = pd.getPayload();
switch (p.getRequestResponseCode()) {
case LOAD_REQUEST:
logger.writeUDP("Received LOAD_REQUEST", LogLevel.Action);
assert p instanceof LoadRequest : "payload must be an instance of LoadRequest";
if (!(p instanceof LoadRequest)) {
sendInternalError(pd);
} else {
String filename = ((LoadRequest)p).getFilename();
long offset = ((LoadRequest)p).getOffset();
long maxSizePartialContent = ((LoadRequest)p).getMaxSizePartialContent();
try {
byte[] fullLoad = Files.readAllBytes(Paths.get(baseDirectory + filename));
long sizeToSend = 0;
if (fullLoad.length - offset < maxSizePartialContent) {
logger.writeUDP("Sending last partialContent", LogLevel.Debug);
sizeToSend = fullLoad.length - offset;
} else {
sizeToSend = maxSizePartialContent;
}
logger.writeUDP("maxSizePartialContent: " + maxSizePartialContent, LogLevel.Debug);
logger.writeUDP("Sending " + filename + " from " + offset + " to " + (offset + sizeToSend), LogLevel.Debug);
byte[] load = Arrays.copyOfRange(fullLoad, (int)offset, (int)(offset + sizeToSend));
if (Arrays.binarySearch(fileList, filename) >= 0) {
try {
if (load.length == 0) {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.EMPTY_FILE)));
} else {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new FilePart(filename, fullLoad.length, offset, load))));
}
} catch (Exception e2) {
logger.writeUDP(e2, LogLevel.Error);
}
} else {
logger.writeUDP("File requested not found: `" + filename + "` " + Arrays.binarySearch(fileList, filename), LogLevel.Debug);
logger.writeUDP("File list:", LogLevel.Debug);
for (String f: fileList) {
logger.writeUDP("- " + f, LogLevel.Debug);
}
throw new IOException(); // to send a NOT_FOUND in the catch block
}
} catch (IOException e) {
try {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.NOT_FOUND)));
} catch (Exception e2) {
logger.writeUDP(e2, LogLevel.Error);
}
}
}
break;
case LIST_REQUEST:
logger.writeUDP("Received LIST_REQUEST", LogLevel.Action);
try {
if (fileList.length == 0) {
logger.writeUDP("Sending EMPTY_DIRECTORY", LogLevel.Action);
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.EMPTY_DIRECTORY)));
} else {
logger.writeUDP("Sending LIST_RESPONSE", LogLevel.Action);
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new FileList(fileList))));
}
} catch (Exception e2) {
logger.writeUDP(e2, LogLevel.Error);
}
break;
case HASH_REQUEST:
logger.writeUDP("Received HASH_REQUEST", LogLevel.Action);
sendHashResponse(pd);
break;
default:
sendInternalError(pd);
}
} catch (IOException e) {
} catch (SocketClosed e) {
} catch (TransmissionError e) {
} catch (ProtocolError e) {
} catch (VersionError e) {
} catch (InternalError e) {
} catch (SizeError e) {
}
}
}
/** Initialize local list of all files allowed to be shared.
*/
private void initFileList() {
File folder = new File(baseDirectory);
Vector<String> v = new Vector<String>();
File[] files = folder.listFiles();
/* Add non-recursively files's names to fileList */
for (File f : files) {
if (f.isFile()) {
v.add(f.getName());
}
}
fileList = new String[v.size()];
v.toArray(fileList);
Arrays.sort(fileList);
}
/** Init sha512 map.
*/
private void initSha512() {
for(String f: fileList) {
try {
MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
md.reset();
} catch (NoSuchAlgorithmException e) {
logger.writeUDP("sha512 not supported", LogLevel.Error);
} catch (IOException e) {
logger.writeUDP("cannot read " + f, LogLevel.Warning);
}
}
}
/** Send an internal error message.
* @param pd ProtocolP2PPacketUDP to respond
*/
private void sendInternalError(ProtocolP2PPacketUDP pd) {
logger.writeUDP("Internal Error", LogLevel.Warning);
try {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR)));
} catch (Exception e) {
logger.writeUDP(e, LogLevel.Error);
}
}
/** Send hash response to hash request
* @param pd Request received
*/
private void sendHashResponse(ProtocolP2PPacketUDP pd) {
Payload p = pd.getPayload();
assert p instanceof HashRequest : "payload must be an instance of HashRequest";
if (!(p instanceof HashRequest)) {
sendInternalError(pd);
} else {
String filename = ((HashRequest)p).getFilename();
if (Arrays.binarySearch(fileList, filename) >= 0) {
Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
switch (h) {
case SHA512:
hashes.put(h, sha512.get(filename));
break;
case MD5:
default:
hashes.put(h, new byte[0]);
break;
}
}
try {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new HashResponse(filename, hashes))));
} catch (Exception e) {
logger.writeUDP(e, LogLevel.Error);
}
} else {
// file not found
try {
pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.NOT_FOUND)));
} catch (Exception e) {
logger.writeUDP(e, LogLevel.Error);
}
}
}
}
}