Dart client Socket connecting but not sending data to server? - sockets

Question

I have a server running on a Raspberry Pi which is accessible from a browser.
http://192.168.1.67:55XXX/?email=a#b.com
yields:-
{Order=[{no=0, day_0=1, price=0, name=PPAC SUPERTHERM 20K, display_colour=blue, notice=1, special_order=false}, {no=1, day_0=1, price=0, name=SLACK 50KG , display_colour=blue, notice=1, special_order=false}, {no=0, day_0=1, price=0, name=PPAC SUPERTHERM 20K, display_colour=blue, day_5=1, notice=1, special_order=false, day_3=1}, {no=1, day_0=1, price=0, name=SLACK 50KG , display_colour=blue, day_5=1, notice=1, special_order=false, day_3=1}], Details={address=xx Farriers Lea, phone=0xxxx 606635, name=Fred Bloggs, mobile=, details=end shed on drive, email=a#b.com}}
I am using VSCODE to debug dart code.
my dart code:-
String remote_ip = '192.168.1.67'; //212.159.118.177';
var remote_port = 55XXX;
Socket socket;
String _dataToBeSent = "http://?email=a#b.com\n";
var reply;
// connect
main(List<String> arguments) async {
await _remoteServerConnect();
}
// REMOTE SERVER CONNECT
Future _remoteServerConnect() async {
// await Socket.connect(remote_ip, remote_port).then((Socket sock){
await Socket.connect(remote_ip, remote_port).then((Socket sock) {
socket = sock;
print('Got connected ${socket.remoteAddress}');
socket.listen(dataHandler,
onError: errorHandler, onDone: doneHandler, cancelOnError: false);
}).catchError((AsyncError e) {
print("Unable to connect: $e");
exit(1);
});
}
void dataHandler(data) async {
await print('"'+String.fromCharCodes(data).trim()+'"');
if (String.fromCharCodes(data).trim().endsWith('html')) {
print("Send Data = $_dataToBeSent");
socket.add(utf8.encode(_dataToBeSent));
// socket.writeln(_dataToBeSent);
socket.flush();
await Future.delayed(Duration(seconds: 5));
}
}
void errorHandler(error, StackTrace trace) {
print(error);
}
void doneHandler() {
// socket.destroy();
exit(0);
}
The dart debug consol yields:-
Connecting to VM Service at ws://127.0.0.1:54799/kE9Xa1JQclk=/ws
Got connected InternetAddress('192.168.1.67', IPv4)
"HTTP/1.1 200 OK" <sent by server
"ContentType: text/html" <sent by server
Send Data = http://?email=a#b.com
Exited
The server consol yields:-
Server is ready
WEB Client connected: /192.168.1.66
05.08/10:34:21.17 - Waiting for command..
05.08/10:34:31.80 - Socket Timeout
05.08/10:34:31.82 - Done -------------
05.08/10:34:31.82 - Waiting for command..
Connection has been closed
Server is ready
It would seem the
socket.add(utf8.encode(_dataToBeSent));
// socket.writeln(_dataToBeSent);
socket.flush();
did not send data to the server?? Why?? any ideas gratefully received!
Disabling my dev machines firewall did NOT improve answer!
Steve

Answer 1

The server used
final DataInputStream in = new DataInputStream(clientSocket.getInputStream());
while (estimatedTime < 60000) {
report("Waiting for command..");
try {
// in.readNBytes(command.data, 0, command.length);
in.readFully(command.data);
to receive the data command.data is 100bytes long so was waiting for the complete input. I padded to 100 bytes worked fine - will sort a better solution later.