/**
* Returns user feedback.
*
* @param info information string
* @param ok success/error flag
* @throws IOException I/O exception
*/
private void info(final String info, final boolean ok) throws IOException {
// write feedback to log file
log.write(this, ok ? OK : ERROR_C + info, perf);
// send {MSG}0 and (0|1) as (success|error) flag
out.writeString(info);
send(ok);
}
/**
* Executes the specified command.
*
* @param cmd command to be executed
* @throws IOException I/O exception
*/
private void execute(final Command cmd) throws IOException {
log.write(this, cmd + " [...]");
final DecodingInput di = new DecodingInput(in);
try {
cmd.setInput(di);
cmd.execute(context);
success(cmd.info());
} catch (final BaseXException ex) {
di.flush();
error(ex.getMessage());
}
}
/** Exits the session. */
public synchronized void quit() {
running = false;
if (log != null) log.write(this, "LOGOUT " + context.user.name, OK);
// wait until running command was stopped
if (command != null) {
command.stop();
while (command != null) Performance.sleep(50);
}
context.delete(this);
try {
new Close().execute(context);
socket.close();
if (events) {
esocket.close();
// remove this session from all events in pool
for (final Sessions s : context.events.values()) s.remove(this);
}
} catch (final Exception ex) {
if (log != null) log.write(ex.getMessage());
Util.stack(ex);
}
}
@Override
public void run() {
// initialize the session via cram-md5 authentication
try {
final String ts = Long.toString(System.nanoTime());
final byte[] address = socket.getInetAddress().getAddress();
// send {TIMESTAMP}0
out = PrintOutput.get(socket.getOutputStream());
out.print(ts);
send(true);
// evaluate login data
in = new BufferInput(socket.getInputStream());
// receive {USER}0{PASSWORD}0
final String us = in.readString();
final String pw = in.readString();
context.user = context.users.get(us);
running = context.user != null && md5(string(context.user.password) + ts).equals(pw);
// write log information
if (running) {
log.write(this, "LOGIN " + context.user.name, OK);
// send {OK}
send(true);
server.unblock(address);
context.add(this);
} else {
if (!us.isEmpty()) log.write(this, ACCESS_DENIED + COLS + us);
new ClientDelayer(server.block(address), this, server).start();
}
} catch (final IOException ex) {
Util.stack(ex);
log.write(ex.getMessage());
return;
}
if (!running) return;
// authentification done, start command loop
ServerCmd sc = null;
String cmd = null;
try {
while (running) {
command = null;
try {
final int b = in.read();
if (b == -1) {
// end of stream: exit session
quit();
break;
}
last = System.currentTimeMillis();
perf.time();
sc = ServerCmd.get(b);
cmd = null;
if (sc == ServerCmd.CREATE) {
create();
} else if (sc == ServerCmd.ADD) {
add();
} else if (sc == ServerCmd.WATCH) {
watch();
} else if (sc == ServerCmd.UNWATCH) {
unwatch();
} else if (sc == ServerCmd.REPLACE) {
replace();
} else if (sc == ServerCmd.STORE) {
store();
} else if (sc != ServerCmd.COMMAND) {
query(sc);
} else {
// database command
cmd = new ByteList().add(b).add(in.readBytes()).toString();
}
} catch (final IOException ex) {
// this exception may be thrown if a session is stopped
quit();
break;
}
if (sc != ServerCmd.COMMAND) continue;
// parse input and create command instance
try {
command = new CommandParser(cmd, context).parseSingle();
} catch (final QueryException ex) {
// log invalid command
final String msg = ex.getMessage();
log.write(this, cmd, ERROR_C + msg);
// send 0 to mark end of potential result
out.write(0);
// send {INFO}0
out.writeString(msg);
// send 1 to mark error
send(false);
continue;
}
// start timeout
command.startTimeout(context.mprop.num(MainProp.TIMEOUT));
log.write(this, command.toString().replace('\r', ' ').replace('\n', ' '));
// execute command and send {RESULT}
boolean ok = true;
String info;
try {
command.execute(context, new EncodingOutput(out));
info = command.info();
} catch (final BaseXException ex) {
ok = false;
info = ex.getMessage();
if (info.startsWith(INTERRUPTED)) info = TIMEOUT_EXCEEDED;
}
// stop timeout
command.stopTimeout();
// send 0 to mark end of result
out.write(0);
// send info
info(info, ok);
// stop console
if (command instanceof Exit) {
command = null;
quit();
}
}
} catch (final IOException ex) {
log.write(this, sc == ServerCmd.COMMAND ? cmd : sc, ERROR_C + ex.getMessage());
Util.debug(ex);
command = null;
quit();
}
command = null;
}
/**
* Processes the query iterator.
*
* @param sc server command
* @throws IOException I/O exception
*/
private void query(final ServerCmd sc) throws IOException {
// iterator argument (query or identifier)
String arg = in.readString();
String err = null;
try {
final QueryListener qp;
if (sc == ServerCmd.QUERY) {
final String query = arg;
qp = new QueryListener(query, context);
arg = Integer.toString(id++);
queries.put(arg, qp);
// send {ID}0
out.writeString(arg);
// write log file
log.write(this, sc + "(" + arg + ')', query, OK, perf);
} else {
// find query process
qp = queries.get(arg);
// ID has already been removed
if (qp == null) {
if (sc != ServerCmd.CLOSE) throw new IOException("Unknown Query ID: " + arg);
} else if (sc == ServerCmd.BIND) {
final String key = in.readString();
final String val = in.readString();
final String typ = in.readString();
qp.bind(key, val, typ);
log.write(this, sc + "(" + arg + ')', key, val, typ, OK, perf);
} else if (sc == ServerCmd.ITER) {
qp.execute(true, out, true);
} else if (sc == ServerCmd.EXEC) {
qp.execute(false, out, true);
} else if (sc == ServerCmd.INFO) {
out.print(qp.info());
} else if (sc == ServerCmd.OPTIONS) {
out.print(qp.options());
} else if (sc == ServerCmd.CLOSE) {
queries.remove(arg);
} else if (sc == ServerCmd.NEXT) {
throw new Exception("Protocol for query iteration is out-of-dated.");
}
// send 0 as end marker
out.write(0);
}
// send 0 as success flag
out.write(0);
// write log file (bind and execute have been logged before)
if (sc != ServerCmd.BIND) log.write(this, sc + "(" + arg + ')', OK, perf);
} catch (final Exception ex) {
// log exception (static or runtime)
err = ex.getMessage();
log.write(this, sc + "(" + arg + ')', ERROR_C + err);
queries.remove(arg);
}
if (err != null) {
// send 0 as end marker, 1 as error flag, and {MSG}0
out.write(0);
out.write(1);
out.writeString(err);
}
out.flush();
}