我正在尝试构建 Paranoid Pirate Pattern 的后半部分,一个将工作发送到一组 DEALER Node 的 ROUTER(我可能误解了该图)。现在我只希望经销商回应工作或只是发回一条“完成”的消息。问题是工作 Node (DEALER)从未收到任何消息。
var buildSocket, connectionTemplate, delay, frontPort, log, q, qPort, worker, workerPort, zmq;
zmq = require("zmq");
frontPort = 5000;
qPort = 5100;
workerPort = 5200;
connectionTemplate = "tcp://127.0.0.1:";
log = console.log;
debugger;
delay = process.argv[2] || 1000;
buildSocket = function(desc, socketType, port) {
var socket;
log("creating " + socketType + " socket");
socket = zmq.socket(socketType);
socket.identity = "" + desc + "-" + socketType + "-" + process.pid + "-" + port;
return socket;
};
q = buildSocket('q_output', 'router', qPort);
worker = buildSocket('worker', 'dealer', workerPort);
worker.bind("" + connectionTemplate + workerPort);
q.connect("" + connectionTemplate + workerPort);
q.on('message', function() {
var args;
args = Array.apply(null, arguments);
log('queue received ' + JSON.stringify(arguments));
return worker.send('work done');
});
worker.on('message', function() {
var args;
log('back received ' + JSON.stringify(arguments));
args = Array.apply(null, arguments);
return q.send(args);
});
setInterval((function() {
var value;
value = Math.floor(Math.random() * 100);
console.log(q.identity + ": sending " + value);
q.send(value);
}), delay);
“消息”事件上的队列和工作线程永远不会触发。我的理解是,您设置 ROUTER Node ,将其绑定(bind)到端口(用于返回消息),设置 DEALER Node 并将它们绑定(bind)到端口,然后将 ROUTER 连接到 DEALER 端口并开始发送消息。在实践中,消息被发送但从未被接收:
creating router socket
creating dealer socket
q_output-router-60326-5100: sending 30
q_output-router-60326-5100: sending 25
q_output-router-60326-5100: sending 65
q_output-router-60326-5100: sending 68
q_output-router-60326-5100: sending 50
q_output-router-60326-5100: sending 88
最佳答案
这里的事情有点倒退了。将 DEALER
套接字视为修改后的 REQ
套接字...它应该向路由器发起消息。 ROUTER
套接字更像是修改后的 REP
套接字...它应该响应经销商发送的初始请求。
您不需要严格遵循ROUTER/DEALER
配对的模式...但这确实会让事情变得更加容易,所以您应该在学习时坚持下去。
从您的代码中让我印象深刻的第二件事是您的消息处理程序,您发送消息的套接字是错误的。
以这段代码为例(直接复制,无需修改):
q.on('message', function() {
var args;
args = Array.apply(null, arguments);
log('queue received ' + JSON.stringify(arguments));
return worker.send('work done');
});
...(在伪代码中):
when `q` receives a message from `worker`
print out the message we received
now have `worker` send *another* message that says "work done"
您想要的是更像以下内容(简化的):
var zmq = require("zmq");
var q = zmq.socket('router');
var worker = zmq.socket('dealer');
// I've switched it so the router is binding and the worker is connecting
// this is somewhat arbitrary, but generally I'd consider workers to be less
// reliable, more transient, and also more numerous. I'd think of the queue
// as the "server"
// I've used bindSync, which is synchronous, but that's typically OK in the
// startup phase of a script, and it simplifies things. If you're spinning
// up new sockets in the middle of your script, using the async bind()
// is more appropriate
q.bindSync('tcp://127.0.0.1:5200');
worker.connect('tcp://127.0.0.1:5200');
q.on('message', function() {
var args;
args = Array.apply(null, arguments);
log('queue received ' + JSON.stringify(arguments));
// if we've received a message at our queue, we know the worker is ready for
// more work, so we ready some new data, regardless of whether we
// received work back
var value = Math.floor(Math.random() * 100);
// note that the socket that received the message is responding back
if (args[1].toString() == 'ready') console.log('worker now online');
else console.log('work received: '+args[1].toString());
// we need to specify the "ID" of our worker as the first frame of
// the message
q.send([args[0], value]);
// we don't need to return anything, the return value of a
// callback is ignored
});
worker.on('message', function() {
var args;
log('back received ' + JSON.stringify(arguments));
args = Array.apply(null, arguments);
// we're just echoing back the "work" we received from the queue
// for additional "workiness", we wait somewhere between 10-1000
// milliseconds to respond
setTimeout(function() {
worker.send(args[0].toString());
}, parseInt(args[0].toString())*10);
});
setTimeout((function() {
var value;
console.log('WORKER STARTING UP');
// the worker starts the communication, indicating it's ready
// rather than the queue just blindly sending work
worker.send('ready'); // sending the first message, which we catch above
}), 500); // In my experience, half a second is more than enough, YMMV
...如您所见,模式是:
- 工作人员表示已准备就绪
- 队列发送可用工作
- 工作人员完成工作并发回
- 队列接收已完成的工作并发回更多工作
- 转到3
关于node.js - 如何让 ROUTER -> DEALER 进行回显?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/24918797/