/// <summary>
/// Based on zmsg_dump
/// https://github.com/imatix/zguide/blob/f94e8995a5e02d843434ace904a7afc48e266b3f/articles/src/multithreading/zmsg.c
/// </summary>
/// <param name="zmsg"></param>
/// <param name="format"></param>
/// <param name="args"></param>
public static void DumpZmsg(this ZMessage zmsg, string format = null, params object[] args)
{
if (!string.IsNullOrWhiteSpace(format))
{
format.DumpString(args);
}
using (var dmsg = zmsg.Duplicate())
foreach (var zfrm in dmsg)
{
zfrm.DumpZfrm();
}
}
public void SendToBroker(string command, string option, ZMessage msg)
{
using (msg = msg != null ? msg.Duplicate() : new ZMessage())
{
if (!string.IsNullOrEmpty(option))
msg.Prepend(new ZFrame(option));
msg.Prepend(new ZFrame(command));
msg.Prepend(new ZFrame(MdpCommon.MDPW_WORKER));
msg.Prepend(new ZFrame(string.Empty));
if (Verbose)
msg.DumpZmsg("I: sending '{0:X}|{0}' to broker", command.ToMdCmd());
Worker.Send(msg);
}
}
public void SendToBroker(string command, string option, ZMessage msg)
{
using (msg = msg != null ? msg.Duplicate() : new ZMessage())
{
if (!string.IsNullOrEmpty(option))
{
msg.Prepend(new ZFrame(option));
}
msg.Prepend(new ZFrame(command));
msg.Prepend(new ZFrame(MdpCommon.MDPW_WORKER));
msg.Prepend(new ZFrame(string.Empty));
if (Verbose)
{
msg.DumpZmsg("I: sending '{0:X}|{0}' to broker", command.ToMdCmd());
}
Worker.Send(msg);
}
}
public void ControlMessage(ZMessage msg)
{
// This method processes one message from our frontend class
// (it's going to be CONNECT or REQUEST):
string command;
using (var commandFrame = msg.Pop())
{
command = commandFrame.ReadString();
}
if (command == "CONNECT")
{
string endpoint = msg[0].ReadString();
Console.WriteLine("I: connecting to {0}...", endpoint);
Router.Connect(endpoint);
var server = new Server(endpoint);
this.Servers.Add(server);
this.Actives.Add(server);
}
else if (command == "REQUEST")
{
if (this.Request != null)
{
// Strict request-reply cycle
throw new InvalidOperationException();
}
// Prefix request with sequence number and empty envelope
msg.Prepend(new ZFrame(++sequence));
// Take ownership of request message
this.Request = msg.Duplicate();
// Request expires after global timeout
this.Expires = DateTime.UtcNow + GLOBAL_TIMEOUT;
}
}
/// <summary>
/// Based on zmsg_dump
/// https://github.com/imatix/zguide/blob/f94e8995a5e02d843434ace904a7afc48e266b3f/articles/src/multithreading/zmsg.c
/// </summary>
/// <param name="zmsg"></param>
/// <param name="format"></param>
/// <param name="args"></param>
public static void DumpZmsg(this ZMessage zmsg, string format, params object[] args)
{
format.DumpString(args);
using (var dmsg = zmsg.Duplicate())
foreach (var zfrm in dmsg)
{
byte[] data = zfrm.Read();
long size = zfrm.Length;
// Dump the message as text or binary
bool isText = true;
for (int i = 0; i < size; i++)
{
if (data[i] < 32 || data[i] > 127)
{
isText = false;
}
}
string datastr = isText ? Encoding.UTF8.GetString(data) : data.ToHexString();
"\tD: [{0,3:D3}]:{1}".DumpString(size, datastr);
}
}
// .split worker send method
// This method formats and sends a command to a worker. The caller may
// also provide a command option, and a message payload:
public void Send(string command, string option, ZMessage msg)
{
msg = msg != null
? msg.Duplicate()
: new ZMessage();
// Stack protocol envelope to start of message
if (!string.IsNullOrEmpty(option))
{
msg.Prepend(new ZFrame(option));
}
msg.Prepend(new ZFrame(command));
msg.Prepend(new ZFrame(MdpCommon.MDPW_WORKER));
// Stack routing envelope to start of message
msg.Wrap(Identity.Duplicate());
if (Broker.Verbose)
{
msg.DumpZmsg("I: sending '{0:X}|{0}' to worker", command.ToMdCmd());
}
Broker.Socket.Send(msg);
}
// .split worker send method
// This method formats and sends a command to a worker. The caller may
// also provide a command option, and a message payload:
public void Send(string command, string option, ZMessage msg)
{
msg = msg != null
? msg.Duplicate()
: new ZMessage();
// Stack protocol envelope to start of message
if (!string.IsNullOrEmpty(option))
msg.Prepend(new ZFrame(option));
msg.Prepend(new ZFrame(command));
msg.Prepend(new ZFrame(MdpCommon.MDPW_WORKER));
// Stack routing envelope to start of message
msg.Wrap(Identity.Duplicate());
if(Broker.Verbose)
msg.DumpZmsg("I: sending '{0:X}|{0}' to worker", command.ToMdCmd());
Broker.Socket.Send(msg);
}
// .split send request and wait for reply
// Here is the {{send}} method. It sends a request to the broker and gets
// a reply even if it has to retry several times. It takes ownership of
// the request message, and destroys it when sent. It returns the reply
// message, or NULL if there was no reply after multiple attempts:
public ZMessage Send(string service, ZMessage request, CancellationTokenSource cancellor)
{
if (request == null)
{
throw new InvalidOperationException();
}
// Prefix request with protocol frames
// Frame 1: "MDPCxy" (six bytes, MDP/Client x.y)
// Frame 2: Service name (printable string)
request.Prepend(new ZFrame(service));
request.Prepend(new ZFrame(MdpCommon.MDPC_CLIENT));
if (Verbose)
{
request.DumpZmsg("I: send request to '{0}' service:", service);
}
int retriesLeft = Retries;
while (retriesLeft > 0 && !cancellor.IsCancellationRequested)
{
if (cancellor.IsCancellationRequested ||
(Console.KeyAvailable && Console.ReadKey(true).Key == ConsoleKey.Escape))
{
_context.Shutdown();
}
// Copy the Request and send on Client
ZMessage msgreq = request.Duplicate();
ZError error;
if (!Client.Send(msgreq, out error))
{
if (Equals(error, ZError.ETERM))
{
cancellor.Cancel();
break; // Interrupted
}
}
var p = ZPollItem.CreateReceiver();
ZMessage msg;
// .split body of send
// On any blocking call, {{libzmq}} will return -1 if there was
// an error; we could in theory check for different error codes,
// but in practice it's OK to assume it was {{EINTR}} (Ctrl-C):
// Poll the client Message
if (Client.PollIn(p, out msg, out error, Timeout))
{
// If we got a reply, process it
if (Verbose)
{
msg.DumpZmsg("I: received reply");
}
if (msg.Count < 3)
{
throw new InvalidOperationException();
}
using (ZFrame header = msg.Pop())
if (!header.ToString().Equals(MdpCommon.MDPC_CLIENT))
{
throw new InvalidOperationException();
}
using (ZFrame replyService = msg.Pop())
if (!replyService.ToString().Equals(service))
{
throw new InvalidOperationException();
}
request.Dispose();
return(msg);
}
else if (Equals(error, ZError.ETERM))
{
cancellor.Cancel();
break; // Interrupted
}
else if (Equals(error, ZError.EAGAIN))
{
if (--retriesLeft > 0)
{
if (Verbose)
{
"W: no reply, reconnecting...".DumpString();
}
ConnectToBroker();
}
else
{
if (Verbose)
{
"W: permanent error, abandoning".DumpString();
}
break; // Give up
}
}
}
if (cancellor.IsCancellationRequested)
{
"W: interrupt received, killing client...\n".DumpString();
}
request.Dispose();
return(null);
}
public ZMessage Request(ZMessage request)
{
// This method does the hard work. It sends a request to all
// connected servers in parallel (for this to work, all connections
// must be successful and completed by this time). It then waits
// for a single successful reply, and returns that to the caller.
// Any other replies are just dropped:
ZMessage reply = null;
using (request)
{
// Prefix request with sequence number and empty envelope
this.sequence++;
request.Prepend(new ZFrame(this.sequence));
request.Prepend(new ZFrame());
// Blast the request to all connected servers
for (int server = 0; server < this.servers; ++server)
{
using (var outgoing = request.Duplicate())
{
this.socket.Send(outgoing);
}
}
// Wait for a matching reply to arrive from anywhere
// Since we can poll several times, calculate each one
ZError error;
DateTime endtime = DateTime.UtcNow + GLOBAL_TIMEOUT;
var poll = ZPollItem.CreateReceiver();
while (endtime > DateTime.UtcNow)
{
if (this.socket.PollIn(poll, out reply, out error, endtime - DateTime.UtcNow))
{
// Reply is [empty][sequence][OK]
if (reply.Count < 3)
{
throw new InvalidOperationException();
}
reply.RemoveAt(0);
using (ZFrame sequenceFrame = reply.RemoveAt(0, false))
{
int sequence = sequenceFrame.ReadInt32();
if (sequence == this.sequence)
{
break; // Reply is ok
}
}
reply.Dispose();
}
else
{
if (error == ZError.ETERM)
{
break; // Interrupted
}
if (error != ZError.EAGAIN)
{
throw new ZException(error);
}
}
}
}
return(reply);
}
// .split send request and wait for reply
// Here is the {{send}} method. It sends a request to the broker and gets
// a reply even if it has to retry several times. It takes ownership of
// the request message, and destroys it when sent. It returns the reply
// message, or NULL if there was no reply after multiple attempts:
public ZMessage Send(string service, ZMessage request, CancellationTokenSource cancellor)
{
if (request == null)
throw new InvalidOperationException();
// Prefix request with protocol frames
// Frame 1: "MDPCxy" (six bytes, MDP/Client x.y)
// Frame 2: Service name (printable string)
request.Prepend(new ZFrame(service));
request.Prepend(new ZFrame(MdpCommon.MDPC_CLIENT));
if (Verbose)
request.DumpZmsg("I: send request to '{0}' service:", service);
int retriesLeft = Retries;
while (retriesLeft > 0 && !cancellor.IsCancellationRequested)
{
if (cancellor.IsCancellationRequested
|| (Console.KeyAvailable && Console.ReadKey(true).Key == ConsoleKey.Escape))
_context.Shutdown();
// Copy the Request and send on Client
ZMessage msgreq = request.Duplicate();
ZError error;
if (!Client.Send(msgreq, out error))
{
if (Equals(error, ZError.ETERM))
{
cancellor.Cancel();
break; // Interrupted
}
}
var p = ZPollItem.CreateReceiver();
ZMessage msg;
// .split body of send
// On any blocking call, {{libzmq}} will return -1 if there was
// an error; we could in theory check for different error codes,
// but in practice it's OK to assume it was {{EINTR}} (Ctrl-C):
// Poll the client Message
if (Client.PollIn(p, out msg, out error, Timeout))
{
// If we got a reply, process it
if (Verbose)
msg.DumpZmsg("I: received reply");
if(msg.Count < 3)
throw new InvalidOperationException();
using (ZFrame header = msg.Pop())
if (!header.ToString().Equals(MdpCommon.MDPC_CLIENT))
throw new InvalidOperationException();
using (ZFrame replyService = msg.Pop())
if(!replyService.ToString().Equals(service))
throw new InvalidOperationException();
request.Dispose();
return msg;
}
else if (Equals(error, ZError.ETERM))
{
cancellor.Cancel();
break; // Interrupted
}
else if (Equals(error, ZError.EAGAIN))
{
if (--retriesLeft > 0)
{
if (Verbose)
"W: no reply, reconnecting...".DumpString();
ConnectToBroker();
}
else
{
if (Verbose)
"W: permanent error, abandoning".DumpString();
break; // Give up
}
}
}
if (cancellor.IsCancellationRequested)
{
"W: interrupt received, killing client...\n".DumpString();
}
request.Dispose();
return null;
}
public ZMessage Request(ZMessage request)
{
// This method does the hard work. It sends a request to all
// connected servers in parallel (for this to work, all connections
// must be successful and completed by this time). It then waits
// for a single successful reply, and returns that to the caller.
// Any other replies are just dropped:
ZMessage reply = null;
using (request)
{
// Prefix request with sequence number and empty envelope
this.sequence++;
request.Prepend(new ZFrame(this.sequence));
request.Prepend(new ZFrame());
// Blast the request to all connected servers
for (int server = 0; server < this.servers; ++server)
{
using (var outgoing = request.Duplicate())
{
this.socket.Send(outgoing);
}
}
// Wait for a matching reply to arrive from anywhere
// Since we can poll several times, calculate each one
ZError error;
DateTime endtime = DateTime.UtcNow + GLOBAL_TIMEOUT;
var poll = ZPollItem.CreateReceiver();
while (endtime > DateTime.UtcNow)
{
if (this.socket.PollIn(poll, out reply, out error, endtime - DateTime.UtcNow))
{
// Reply is [empty][sequence][OK]
if (reply.Count < 3)
{
throw new InvalidOperationException();
}
reply.RemoveAt(0);
using (ZFrame sequenceFrame = reply.RemoveAt(0, false))
{
int sequence = sequenceFrame.ReadInt32();
if (sequence == this.sequence)
{
break; // Reply is ok
}
}
reply.Dispose();
}
else
{
if (error == ZError.ETERM)
break; // Interrupted
if (error != ZError.EAGAIN)
throw new ZException(error);
}
}
}
return reply;
}
public void ControlMessage(ZMessage msg)
{
// This method processes one message from our frontend class
// (it's going to be CONNECT or REQUEST):
string command = msg.PopString();
if (command == "CONNECT")
{
string endpoint = msg.PopString();
Console.WriteLine("I: connecting to {0}...", endpoint);
this.Router.Connect(endpoint);
var server = new Server(endpoint);
this.Servers.Add(server);
this.Actives.Add(server);
}
else if (command == "REQUEST")
{
if (this.Request != null)
{
// Strict request-reply cycle
throw new InvalidOperationException();
}
// Prefix request with sequence number and empty envelope
msg.Prepend(new ZFrame(++sequence));
// Take ownership of request message
this.Request = msg.Duplicate();
// Request expires after global timeout
this.Expires = DateTime.UtcNow + GLOBAL_TIMEOUT;
}
}
