无法在与 socket.bind() 绑定的套接字上发送消息

Question

我正在尝试制作一个程序，该程序接收数据包，并使用socket.send()-方法将其发送到另一个端口。当我尝试发送消息(带有数据包副本(时，它什么都不会做。不过，数据包收到得很好。

import time
import zmq

context = zmq.Context()
# Socket facing out
push = context.socket(zmq.REQ)
# push.hwm = 1
push.bind("tcp://*:5556")
# Socket facing in
sub = context.socket(zmq.SUB)
sub.bind("tcp://*:5555")
while True:
sub.setsockopt_string(zmq.SUBSCRIBE, "")
msg = sub.recv()
print("test")
push.send_string("test")
print("test2")

当我取消对push.hwm = 1的注释时，它没有帮助。

Answer 1

让我们先对代码进行解密：

import time
import zmq
context = zmq.Context()
push = context.socket( zmq.REQ ) # Socket facing out - THE MOST COMPLICATED ARCHETYPE
# push.hwm = 1                   #        a .hwm() ? - A STRANGE PROMISE IN v17/18
push.bind( "tcp://*:5556" )      # push acquires all ports 5556 to be REQ-served
sub = context.socket( zmq.SUB )  # Socket facing in  + SUB TOPIC LIST MANAGEMENT COSTS
sub.bind(  "tcp://*:5555" )      # sub  acquires all ports 5555 to be SUB-served
while True:
sub.setsockopt_string( zmq.SUBSCRIBE, "" ) # /NEVER/.SET INFINITELY MANY TIMES?
msg = sub.recv()                           # /NEVER/ USE A BLOCKING .recv()
pass;                      print( "test" ) #         CLI - GUI STUB print()
push.send_string( "test" )                 #                        .send()
pass;                      print( "test2" )#         CLI - GUI STUB print()

除了使用push.hwm的一个相当奇怪的承诺之外，它在v3.+之前的Python中不起作用，并且有点"；偏斜"/"扩展"；本机ZeroMQ API：

>> print pull.set_hwm.__doc__
Set the High Water Mark.

On libzmq ≥ 3, this sets both SNDHWM and RCVHWM

.. warning::
New values only take effect for subsequent socket
bind/connects.

应该首先重构此代码。REQ/REP在这里一点用处都没有，因为它没有足够强大的协调dFSA对应方(在删除概念上的REQ-通过从未尝试过.recv()-任何这样的REP-答案而自杀之后，从未将任何REP发送回已经发送的REQ，在这种情况下，它偶尔确实是从未知的(如果存在的话(远程交互的dFSA节点发送的(。

也许会变成这样：

import time
import zmq
ms_TO_WAIT_IN_POLL = 100
def cliShow( aText = "no parameter was fed in" ):
print( "{0:}:: {1:}".format( time.ctime(), aText ) )
context = zmq.Context()
push = context.socket( zmq.PUSH )# Socket facing out - THE zmq.PUSH ARCHETYPE is a right-enough one
push.bind( "tcp://*:5556" )      # push acquires all ports 5556 to be PUSH-served
push.setsockopt( zmq.LINGER, 0 ) # .SET always explicitly, even if "defaults" promise
pull = context.socket( zmq.PULL )# Socket facing in  - THE zmq.PULL ARCHETYPE is a right-enough one
pull.bind( "tcp://*:5555" )      # pull acquires all ports 5555 to be PULL-served
pull.setsockopt( zmq.LINGER, 0 ) # .SET always explicitly, even if "defaults" promise
try:
while True:
if ( 0 == pull.poll( ms_TO_WAIT_IN_POLL, zmq.POLLIN ) ):
cliShow( "No message arrived yet" )     #         CLI - GUI STUB print()
else:
msg  = pull.recv( zmq.NOBLOCK )         # /NEVER/ USE A BLOCKING .recv()
cliShow( "test" )                       #         CLI - GUI STUB print()

push.send_string( "test" )              #                        .send()
cliShow( "test2" )                      #         CLI - GUI STUB print()
except KeyboardInterrupt:
pass
except:
pass
finally:
pull.close()
push.close()
context.term()