I make a script in order to receive servers commands. My goal is to receive the message from server 1...wait wait.. then receive the message from server 2 then execute an action. This actually work using DispatchQueue and DispatchGroup. My code works if servers are running before this app is started.
import UIKit
import Dispatch
let addr = "192.168.0.100"
let addr2 = "192.168.0.104"
let port = 12345 //PORT Num
var buffer = [UInt8](repeating: 0, count: 255)
var buffer2 = [UInt8](repeating: 0, count: 255)
var inpVive1 : InputStream?
var outVive1 : OutputStream?
var inpVive2 : InputStream?
var outVive2 : OutputStream?
let secondsDelay = 0
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let queue:DispatchQueue = DispatchQueue.global(qos: .userInitiated)
let group:DispatchGroup = DispatchGroup()
group.enter()
queue.async {
self.Connection1()
group.leave()
}
group.enter()
queue.async {
self.Connection2()
group.leave()
}
group.notify(queue: queue, execute: {// do something when all tasks in queue complete})
print("Everything is received!!!!!!!!!!!!")
})
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func Connection1() {
print("Listening vive1")
Stream.getStreamsToHost(withName: addr, port: port, inputStream: &inpVive1, outputStream: &outVive1)
if inpVive1 != nil && outVive1 != nil {
let inputStreamVive1 : InputStream = inpVive1!
let outputStreamVive1 : OutputStream = outVive1!
inputStreamVive1.delegate = self as? StreamDelegate
outputStreamVive1.delegate = self as? StreamDelegate
inputStreamVive1.schedule(in: .main, forMode: .defaultRunLoopMode)
outputStreamVive1.schedule(in: .main, forMode: .defaultRunLoopMode)
inputStreamVive1.open()
outputStreamVive1.open()
print("Tunnel vive1 ouvert")
if outputStreamVive1.streamError == nil && inputStreamVive1.streamError == nil {
while true {
let readCharsVive1: Int = inputStreamVive1.read(&buffer, maxLength: buffer.count)
if (readCharsVive1 > 0) {
let readStringVive1: String = NSString(data: NSData(bytes:buffer, length:readCharsVive1) as Data, encoding: String.Encoding.utf8.rawValue)! as String
print("Message received vive1 :", readStringVive1) // data from server
usleep(300 * 1000) // wait 300 msec (just wait. it is no meaning. using as "NOP")
inputStreamVive1.close()
outputStreamVive1.close()
}
else {
print ("server1 closed connection")
inputStreamVive1.close()
outputStreamVive1.close()
break
}
}
}
}
}
func Connection2() {
print("Listening vive2")
Stream.getStreamsToHost(withName: addr2, port: port, inputStream: &inpVive2, outputStream: &outVive2)
if inpVive2 != nil && outVive2 != nil {
let inputStreamVive2 : InputStream = inpVive2!
let outputStreamVive2 : OutputStream = outVive2!
inputStreamVive2.open()
outputStreamVive2.open()
print("Tunnel vive2 ouvert")
if outputStreamVive2.streamError == nil && inputStreamVive2.streamError == nil {
while true {
let readCharsVive2: Int = inputStreamVive2.read(&buffer2, maxLength: buffer2.count)
if (readCharsVive2 > 0) {
let readStringVive2: String = NSString(data: NSData(bytes:buffer2, length:readCharsVive2) as Data, encoding: String.Encoding.utf8.rawValue)! as String
print("Message received vive2 :", readStringVive2) // data from server
usleep(300 * 1000) // wait 300 msec (just wait. it is no meaning. using as "NOP")
inputStreamVive2.close()
outputStreamVive2.close()
}
else {
print ("server2 closed connection")
inputStreamVive2.close()
outputStreamVive2.close()
break
}
}
}
}
}
}
I successfully made a connection to the server when this one it’s already running. Now I would like to be able to wait until it starts in the case it’s not running . Any idea?
Actually this solved my issue :
import UIKit
let addr = "127.0.0.1"
let port = 12345 //PORT Num
var buffer = [UInt8](repeating: 110, count: 4096)
var inputStream : InputStream?
var outputStream : OutputStream?
var animationTimer: Timer!
let readChars: Int = inputStream!.read(&buffer, maxLength: buffer.count)
class ViewController: UIViewController, StreamDelegate {
override func viewDidLoad() {
super.viewDidLoad()
Connection()
}
func Connection() {
Stream.getStreamsToHost(withName: addr, port: port, inputStream: &inputStream, outputStream: &outputStream)
if inputStream != nil && outputStream != nil {
print("connecting")
inputStream?.delegate = self
outputStream?.delegate = self
inputStream?.schedule(in: RunLoop.current, forMode: RunLoopMode.defaultRunLoopMode)
outputStream?.schedule(in: RunLoop.current, forMode: RunLoopMode.defaultRunLoopMode)
print("Start open()")
inputStream?.open()
outputStream?.open()
}
}
func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
if aStream === inputStream {
switch eventCode {
case Stream.Event.errorOccurred:
print("input: ErrorOccurred: \(String(describing: aStream.streamError?.localizedDescription))")
Connection()
break
case Stream.Event.openCompleted:
print("input: OpenCompleted")
break
case Stream.Event.hasBytesAvailable:
print("input: HasBytesAvailable")
print("On est connecté")
if readChars > 0 {
let readString: String = NSString(data: NSData(bytes:buffer, length:readChars) as Data, encoding: String.Encoding.utf8.rawValue)! as String
print(readString) // data from server
inputStream?.close()
outputStream?.close()
}
default:
break
}
}
}
}