static void Main(string[] args)
{
using (var context = new Context(1))
{
using (Socket frontend = context.Socket(SocketType.ROUTER), backend = context.Socket(SocketType.ROUTER))
{
frontend.Bind("tcp://*:5555"); // For Clients
backend.Bind("tcp://*:5556"); // For Workers
// Logic of LRU loop
// - Poll backend always, frontend only if 1+ worker ready
// - If worker replies, queue worker as ready and forward reply
// to client if necessary
// - If client requests, pop next worker and send request to it
// Queue of available workers
var workerQueue = new Queue<byte[]>();
// Handle worker activity on backend
backend.PollInHandler += (socket, revents) =>
{
var zmsg = new ZMessage(socket);
// Use worker address for LRU routing
workerQueue.Enqueue(zmsg.Unwrap());
// Forward message to client if it's not a READY
if (!Encoding.Unicode.GetString(zmsg.Address).Equals(LRU_READY))
{
zmsg.Send(frontend);
}
};
frontend.PollInHandler += (socket, revents) =>
{
// Now get next client request, route to next worker
// Dequeue and drop the next worker address
var zmsg = new ZMessage(socket);
zmsg.Wrap(workerQueue.Dequeue(), new byte[0]);
zmsg.Send(backend);
};
while (true)
{
int rc = Context.Poller(workerQueue.Count > 0
? new List<Socket>(new Socket[] {frontend, backend})
: new List<Socket>(new Socket[] {backend}));
if (rc == -1)
{
break;
}
}
}
}
}
static void Main(string[] args)
{
using (var context = new Context(1))
{
using (var worker = context.Socket(SocketType.REQ))
{
var randomizer = new Random(DateTime.Now.Millisecond);
var identity = ZHelpers.SetID(worker, Encoding.Unicode);
worker.Connect("tcp://localhost:5556");
Console.WriteLine("I: {0} worker ready", identity);
worker.Send("READY");
var cycles = 0;
while (true)
{
var zmsg = new ZMessage(worker);
cycles += 1;
if (cycles > 3 && randomizer.Next(0, 5) == 0)
{
Console.WriteLine("I: {0} simulating a crash", identity);
break;
}
else if (cycles > 3 && randomizer.Next(0, 5) == 0)
{
Console.WriteLine("I: {0} simulating CPU overload", identity);
System.Threading.Thread.Sleep(3000);
}
Console.WriteLine("I: {0} normal reply", identity);
System.Threading.Thread.Sleep(1000);
zmsg.Send(worker);
}
}
}
}
public static void Main(string[] args)
{
var workers = new List<Thread>();
var clients = new List<Thread>();
// Prepare our context and sockets
using (var ctx = new Context(1))
{
using (Socket frontend = ctx.Socket(SocketType.ROUTER), backend = ctx.Socket(SocketType.ROUTER))
{
frontend.Bind("tcp://*:5555");
backend.Bind("tcp://*:5556");
int clientId;
for (clientId = 0; clientId < Program.clients; clientId++)
{
clients.Add(new Thread(ClientTask));
clients[clientId].Start();
}
for (int workerId = 0; workerId < Program.workers; workerId++)
{
workers.Add(new Thread(WorkerTask));
workers[workerId].Start();
}
// Logic of LRU loop
// - Poll backend always, frontend only if 1+ worker ready
// - If worker replies, queue worker as ready and forward reply
// to client if necessary
// - If client requests, pop next worker and send request to it
// Queue of available workers
var workerQueue = new Queue<byte[]>();
// Handle worker activity on backend
backend.PollInHandler += (socket, revents) =>
{
var zmsg = new ZMessage(socket);
// Use worker address for LRU routing
workerQueue.Enqueue(zmsg.Unwrap());
// Forward message to client if it's not a READY
if (!Encoding.Unicode.GetString(zmsg.Address).Equals("READY"))
{
zmsg.Send(frontend);
}
};
frontend.PollInHandler += (socket, revents) =>
{
// Now get next client request, route to next worker
// Dequeue and drop the next worker address
var zmsg = new ZMessage(socket);
zmsg.Wrap(workerQueue.Dequeue(), new byte[0]);
zmsg.Send(backend);
};
while (true)
{
int rc = Context.Poller(workerQueue.Count > 0
? new List<Socket>(new Socket[] {frontend, backend})
: new List<Socket>(new Socket[] {backend}));
if (rc == -1)
{
break;
}
}
}
}
}
private static void WorkerTask()
{
using (var ctx = new Context(1))
{
using (var worker = ctx.Socket(SocketType.REQ))
{
ZHelpers.SetID(worker, Encoding.Unicode);
worker.Connect("tcp://localhost:5556");
// Tell broker we're ready for work
worker.Send("READY", Encoding.Unicode);
while (true)
{
var zmsg = new ZMessage(worker);
Console.WriteLine("Worker: {0}", Encoding.Unicode.GetString(zmsg.Body));
zmsg.StringToBody("OK");
zmsg.Send(worker);
}
}
}
}
static void Main(string[] args)
{
using (var context = new Context(1))
{
int interval = INTERVAL_INIT;
int liveness = HEARTBEAT_LIVENESS;
while (true)
{
int cylces = 0;
using (Socket worker = ConnectWorker(context))
{
worker.PollInHandler += (socket, revents) =>
{
var zmsg = new ZMessage(socket);
byte[] identity = zmsg.Unwrap();
switch (Encoding.Unicode.GetString(zmsg.Address))
{
case PPP_HEARTBEAT:
interval = INTERVAL_INIT;
liveness = HEARTBEAT_LIVENESS;
break;
default:
if (zmsg.FrameCount > 1)
{
if (!doTheWork(cylces++))
{
break;
}
interval = INTERVAL_INIT;
liveness = HEARTBEAT_LIVENESS;
Console.WriteLine("W: work completed");
zmsg.Send(worker);
}
else
{
Console.WriteLine("E: invalied message {0}", identity);
}
break;
};
};
//Send out heartbeats at regular intervals
DateTime heartbeat_at = DateTime.Now.AddMilliseconds(HEARTBEAT_INTERVAL);
while (true)
{
List<Socket> pollItems = new List<Socket>(new Socket[] { worker });
Context.Poller(pollItems, HEARTBEAT_INTERVAL * 1000);
//If liveness hits zero, queue is considered disconnected
if (--liveness <= 0)
{
Console.WriteLine("W: heartbeat failure, can't reach queue.");
Console.WriteLine("W: reconnecting in {0} msecs...", interval);
try
{
Thread.Sleep(interval);
}
catch (System.Exception ex)
{
Console.WriteLine(ex.Message);
}
//Exponential Backoff
if (interval < INTERVAL_MAX)
interval *= 2;
liveness = HEARTBEAT_LIVENESS;
//Break the while loop and start the connection over
break;
}
//Send heartbeat to queue if it's time
if (DateTime.Now > heartbeat_at)
{
heartbeat_at = DateTime.Now.AddMilliseconds(HEARTBEAT_INTERVAL);
ZMessage zmsg = new ZMessage(PPP_HEARTBEAT);
zmsg.Send(worker);
}
}
}
}
}
}
private static void WorkerTask()
{
using (var ctx = new Context(1))
{
using (var worker = ctx.Socket(SocketType.REQ))
{
ZHelpers.SetID(worker, Encoding.Unicode);
worker.Connect(localBeAddress);
var msg = new ZMessage("READY");
msg.Send(worker);
while (true)
{
var recvMsg = new ZMessage(worker);
Console.WriteLine("Worker: {0}", recvMsg.BodyToString());
Thread.Sleep(1000);
recvMsg.StringToBody("OK");
recvMsg.Send(worker);
//var okmsg = new ZMessage("OK");
//okmsg.Send(worker);
}
}
}
}
private static void SendReply(ZMessage msg, Socket cloudfe, Socket localfe)
{
var address = Encoding.Unicode.GetString(msg.Address);
// Route reply to cloud if it's addressed to a broker
if (peers.Count(peerAddress => peerAddress == address) == 1)
{
Console.WriteLine("Sending to cloud frontend");
msg.Send(cloudfe);
}
else
{
Console.WriteLine("Sending to local frontend");
msg.Send(localfe);
}
}