如果未连接，如何退出服务器连接

Question

我有两台服务器，如果服务器 1 无法连接，客户端程序等待并且服务器 2 未获取数据，我的客户端希望向两者发送相同的数据 server.but。我想等server1 1s，如果连接失败，server2 会获取数据。

import socket               
s1 = socket.socket()     
s2 = socket.socket()   
host1 = '192.168.0.3'
port1 = 12345
host2 = '192.168.0.5'
port2=12321               
s1.connect((host1, port1))
s1.send(data)
s2.connect((host2,port2))
s2.send(data)
s1.close()
s2.close()

Answer 1

我认为如果您无法连接到服务器，它会自动抛出异常，如果您捕获到异常，将执行以下行。
例如：-
客户端

import socket
import struct, time
import sys
# server
HOST = "localhost"
PORT = 13

# reference time (in seconds since 1900-01-01 00:00:00)
TIME1970 = 2208988800L # 1970-01-01 00:00:00

# connect to server
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s2 = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

try:
     s.connect((HOST, PORT))
except: # catch *all* exceptions
      e = sys.exc_info()[0]
      print(e)

try:
     s2.connect((HOST, 8037))
except: # catch *all* exceptions
      e = sys.exc_info()[0]



# read 4 bytes, and convert to time value
t = s2.recv(4)
t = struct.unpack("!I", t)[0]
t = int(t - TIME1970)

s.close()

# print results
print "server time is", time.ctime(t)
print "local clock is", int(time.time()) - t, "seconds off"

服务器端

import socket
import struct, time

# user-accessible port
PORT = 8037

# reference time
TIME1970 = 2208988800L

# establish server
service = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
service.bind(("", PORT))
service.listen(1)

print "listening on port", PORT

while 1:
    # serve forever
    channel, info = service.accept()
    print "connection from", info
    t = int(time.time()) + TIME1970
    t = struct.pack("!I", t)
    channel.send(t) # send timestamp
    channel.close() # disconnect

在上面的客户端代码中，一个服务器端口不退出，即 localhost:13，所以它会抛出异常，我捕获了异常，然后执行了错误代码之后的代码，因此连接到服务器 localhost:8037，它返回了数据.

Answer 2

简单加试试

try:
   s1.connect((host1, port1))
   s1.send(data)
except:
   print " s1 not connected"
try:
   s2.connect((host2,port2))
   s2.send(data)
except:
   print"s2 not connected"
s1.close()
s2.close()

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