無法通過Python中的套接字進行客戶端 - 服務器通信

Question

過去兩週，我一直在反駁套接字問題，但無濟於事。我有一臺12臺'客戶'機器和一臺服務器機器。服務器被賦予一個大任務，將其分成12個較小的任務，然後分配給12個客戶端。客戶流失了，一旦他們完成任務，他們應該讓服務器知道他們已經通過套接字通信完成了。出於某種原因，這只是一直工作或根本沒有（服務器和客戶端，只是坐在while循環）。

這裏是服務器上的代碼：

socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
socket.bind(('localhost', RandomPort)) 
socket.listen(0) 
socket.settimeout(0.9) 

[Give all the clients their tasks, then do the following:] 

while 1: 
    data = 'None' 
    IP = [0,0] 
    try: 
     Client, IP = socket.accept() 
     data = Client.recv(1024) 
     if data == 'Done': 
      Client.send('Thanks') 
     for ClientIP in ClientIPList(): 
      if ClientIP == IP[0] and data == 'Done': 
       FinishedCount += 1 
      if FinishedCount == 12: 
       break 
    except: 
     pass 

這裏是所有的客戶端代碼：

[Receive task from server and execute. Once finished, do the following:] 

while 1: 
    try: 
     f = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
     f.connect((IPofServer, RandomPort)) 
     f.settimeout(0.5) 
     f.send('Done') 
     data = f.recv(1024) 
     if data == 'Thanks': 
      f.shutdown(socket.SHUT_RDWR) 
      f.close() 
      break 
    except: 
     f.close() 
     time.sleep(2+random.random()*5) 

我已經使用Wireshark的，發現包被飛來飛去。然而，「FinishedCount」似乎從來沒有增加過...我在設置時錯過了什麼明顯的錯誤？這是我第一次接觸到插座....

謝謝大家提前給予您的幫助！

編輯：我已經作出瞭如下代碼修改：

在服務器上：socket.listen現在socket.listen（5）

Answer 1

好吧，這個我花了一段時間，但我想我想通了什麼造成這樣的：

1. glglgl的答案是正確的 - 使用的「localhost」使機器 只聽本身，而不是其他網絡上的機器。這個 是主要的罪魁禍首。
2. 將que允許的數量從0增加到5減少了 在客戶端 端獲得「連接被拒絕」錯誤的可能性。

3. 我在假定無限 套接字連接的錯誤while循環可以關閉無限快的 - 但是，有一個 無限的，而兩側環有時會導致客戶端 有時會因爲同時重複計算循環不是 同步。當然，這導致'客戶端不可知'finishedCount增加兩次，這導致服務器相信所有 客戶端時，他們沒有。使用CHOWN的代碼（！謝謝 CHOWN），這可以處理這樣的：

   def main(): 
       sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
       sock.bind((HOST, PORT)) 
       sock.listen(0) 
   
       FINISHEDCLIENTS = [] 
   
       while 1: 
        data = 'None' 
        IP = [0, 0] 
        try: 
         client, ip = sock.accept() 
         data = client.recv(1024) 
         print "%s: Server recieved: '%s'" % (time.ctime(), data) 
   
         if data == 'Done': 
          print "%s: Server sending: 'Thanks'" % time.ctime() 
          client.send('Thanks') 
   
          if ip[0] in CLIENT_IPS and ip[0] not in FINISHEDCLIENTS: 
           FINISHEDCLIENTS.append(ip[0]) 
   
           if len(FINISHEDCLIENTS) == 12: 
            #raise MyException 
            break 
   
        except Exception, e: 
         print "%s: Server Exception - %s" % (time.ctime(), e) 
   

   在客戶端，我改變了代碼，這（這裏當然， RandomPort是一樣的一個在上面的服務器腳本）使用：

   SentFlag = 0 
   data = 'no' 
   while SentFlag == 0: 
       try: 
        f = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
        f.connect((IPofServer, RandomPort)) 
        f.settimeout(20) 
        f.send('Done') 
        data = f.recv(1024) 
        if data == 'Thanks': 
         f.shutdown(socket.SHUT_RDWR) 
         f.close() 
         SentFlag = 1 
       except: 
        f.close() 
        time.sleep(2*random.random()) 
   

PS：我.shutdown（）VS .close（諒解）是關閉連接，但不一定是插座如果從事其他通信。 .shutdown（）不管它在做什麼，都會關閉套接字。雖然我沒有任何證據。

我認爲應該這樣做 - 再次感謝您幫助解決此問題！

Answer 2

你的服務器有兩個缺陷：

首先，這將打破內for循環出來，而不是while循環：

if FinishedCount == 12: 
    break 

你while LO op沒有終止條件。

其次，這種模式：

try: 
    ... 
except: 
    pass 

應該從未使用。你吞噬每一個異常，並忽略它。這是不好的做法，並會導致錯誤。它應該是：

try: 
    ... 
except OneExceptionIWantToIgnore: 
    pass 
except: 
    raise 

修復這兩個問題，並返回給我們結果。

Answer 3

呼叫監聽（0）設置沒有積壓，所以你更有可能得到拒絕的連接。服務器端套接字也永遠不會關閉。現在擺脫try/excepts，以便您可以看到真正的問題。否則，處理顯式的socket.error異常。

Answer 4

我相信這裏的問題是使用RandomPort。每個客戶端和服務器都需要在同一端口上發送/接收才能工作。而且，for ClientIP in ClientIPList(): if ClientIP == IP[0] and data == 'Done':循環有點多餘且不必要。它可以替換爲if ip[0] in clientIpList:，並放置在其上方的if data == 'Done':內。

其他一些想法;不要將名稱與您導入的名稱命名爲相同的名稱（如socket = socket.socket(..)），因爲那樣您將無法再使用導入的庫。除非客戶端/服務器都在同一個系統上運行或者在同一個子網內運行，否則settimeout(0.5)是簡短的方法。

我將您的代碼與python socket documentation中的一些example code合併，並提出了一些可以輕鬆適應您的需求的方法。這裏是腳本;下面粘貼運行服務器和12個客戶端的輸出。

server.py：

#!/usr/bin/python 
# server.py 

import sys 
import socket 
import time 

HOST = '' 
PORT = 50008 

CLIENT_IPS = ["10.10.1.11"] 

## No longer necessary if the nested loop isn't needed 
#class MyException(Exception): 
# pass 

def main(): 
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
    sock.bind((HOST, PORT)) 
    sock.listen(0) 

    finishedCount = 0 

    while 1: 
     data = 'None' 
     IP = [0, 0] 
     try: 
      client, ip = sock.accept() 
      data = client.recv(1024) 
      print "%s: Server recieved: '%s'" % (time.ctime(), data) 

      if data == 'Done': 
       print "%s: Server sending: 'Thanks'" % time.ctime() 
       client.send('Thanks') 

       if ip[0] in CLIENT_IPS: 
        finishedCount += 1 
        print "%s: Finished Count: '%d'" % (time.ctime(), finishedCount) 

        if finishedCount == 12: 
         #raise MyException 
         break 

     except Exception, e: 
      print "%s: Server Exception - %s" % (time.ctime(), e) 

     #except MyException: 
     # print "%s: All clients accounted for. Server ending, goodbye!" % time.ctime() 
     # break 

    # close down the socket, ignore closing exceptions 
    try: 
     sock.close() 
    except: 
     pass 
    print "%s: All clients accounted for. Server ending, goodbye!" % time.ctime() 

if __name__ == '__main__': 
    sys.exit(main()) 

client.py：從服務器在同一時間運行

[ 10:52 jon@hozbox.com ~/SO/python ]$ for x in {1..12}; do ./client.py $x && sleep 2; done 
Fri Nov 18 10:52:44 2011: Client 1: Sending - 'Done'.. 
Fri Nov 18 10:52:44 2011: Client 1: Recieved - 'Thanks' 
Fri Nov 18 10:52:44 2011: Client 1: Finished, goodbye! 
Fri Nov 18 10:52:46 2011: Client 2: Sending - 'Done'.. 
Fri Nov 18 10:52:46 2011: Client 2: Recieved - 'Thanks' 
Fri Nov 18 10:52:46 2011: Client 2: Finished, goodbye! 
Fri Nov 18 10:52:48 2011: Client 3: Sending - 'Done'.. 
Fri Nov 18 10:52:48 2011: Client 3: Recieved - 'Thanks' 
Fri Nov 18 10:52:48 2011: Client 3: Finished, goodbye! 
Fri Nov 18 10:52:50 2011: Client 4: Sending - 'Done'.. 
Fri Nov 18 10:52:50 2011: Client 4: Recieved - 'Thanks' 
Fri Nov 18 10:52:50 2011: Client 4: Finished, goodbye! 
Fri Nov 18 10:52:52 2011: Client 5: Sending - 'Done'.. 
Fri Nov 18 10:52:52 2011: Client 5: Recieved - 'Thanks' 
Fri Nov 18 10:52:52 2011: Client 5: Finished, goodbye! 
Fri Nov 18 10:52:54 2011: Client 6: Sending - 'Done'.. 
Fri Nov 18 10:52:54 2011: Client 6: Recieved - 'Thanks' 
Fri Nov 18 10:52:54 2011: Client 6: Finished, goodbye! 
Fri Nov 18 10:52:56 2011: Client 7: Sending - 'Done'.. 
Fri Nov 18 10:52:56 2011: Client 7: Recieved - 'Thanks' 
Fri Nov 18 10:52:56 2011: Client 7: Finished, goodbye! 
Fri Nov 18 10:52:58 2011: Client 8: Sending - 'Done'.. 
Fri Nov 18 10:52:58 2011: Client 8: Recieved - 'Thanks' 
Fri Nov 18 10:52:58 2011: Client 8: Finished, goodbye! 
Fri Nov 18 10:53:01 2011: Client 9: Sending - 'Done'.. 
Fri Nov 18 10:53:01 2011: Client 9: Recieved - 'Thanks' 
Fri Nov 18 10:53:01 2011: Client 9: Finished, goodbye! 
Fri Nov 18 10:53:03 2011: Client 10: Sending - 'Done'.. 
Fri Nov 18 10:53:03 2011: Client 10: Recieved - 'Thanks' 
Fri Nov 18 10:53:03 2011: Client 10: Finished, goodbye! 
Fri Nov 18 10:53:05 2011: Client 11: Sending - 'Done'.. 
Fri Nov 18 10:53:05 2011: Client 11: Recieved - 'Thanks' 
Fri Nov 18 10:53:05 2011: Client 11: Finished, goodbye! 
Fri Nov 18 10:53:07 2011: Client 12: Sending - 'Done'.. 
Fri Nov 18 10:53:07 2011: Client 12: Recieved - 'Thanks' 
Fri Nov 18 10:53:07 2011: Client 12: Finished, goodbye! 
[ 10:53 jon@hozbox.com ~/SO/python ]$ 

輸出：：從運行12個客戶

#!/usr/bin/python 
# client.py 

import sys 
import time 
import socket 
import random 

HOST = '10.10.1.11' 
PORT = 50008 

def main(n): 
    while 1: 
     try: 
      s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
      s.connect((HOST, PORT)) 

      s.send('Done') 
      print "%s: Client %d: Sending - 'Done'.." % (time.ctime(), n) 

      data = s.recv(1024) 
      print "%s: Client %d: Recieved - '%s'" % (time.ctime(), n, data) 

      if data == 'Thanks': 
       break 

     except Exception, e: 
      print "%s: Client %d: Exception - '%s'" % (time.ctime(), n, e) 
      time.sleep(2 + random.random() * 5) 
     finally: 
      try: 
       s.shutdown(socket.SHUT_RDWR) 
      except: 
       pass 
      finally: 
       try: 
        s.close() 
       except: 
        pass 

    print "%s: Client %d: Finished, goodbye!" % (time.ctime(), n) 


if __name__ == '__main__': 
    if len(sys.argv) > 1 and sys.argv[1].isdigit(): 
     sys.exit(main(int(sys.argv[1]))) 

輸出

[ 10:52 jon@hozbox.com ~/SO/python ]$ ./server.py 
Fri Nov 18 10:52:44 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:44 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:44 2011: Finished Count: '1' 
Fri Nov 18 10:52:46 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:46 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:46 2011: Finished Count: '2' 
Fri Nov 18 10:52:48 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:48 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:48 2011: Finished Count: '3' 
Fri Nov 18 10:52:50 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:50 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:50 2011: Finished Count: '4' 
Fri Nov 18 10:52:52 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:52 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:52 2011: Finished Count: '5' 
Fri Nov 18 10:52:54 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:54 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:54 2011: Finished Count: '6' 
Fri Nov 18 10:52:56 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:56 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:56 2011: Finished Count: '7' 
Fri Nov 18 10:52:58 2011: Server recieved: 'Done' 
Fri Nov 18 10:52:58 2011: Server sending: 'Thanks' 
Fri Nov 18 10:52:58 2011: Finished Count: '8' 
Fri Nov 18 10:53:01 2011: Server recieved: 'Done' 
Fri Nov 18 10:53:01 2011: Server sending: 'Thanks' 
Fri Nov 18 10:53:01 2011: Finished Count: '9' 
Fri Nov 18 10:53:03 2011: Server recieved: 'Done' 
Fri Nov 18 10:53:03 2011: Server sending: 'Thanks' 
Fri Nov 18 10:53:03 2011: Finished Count: '10' 
Fri Nov 18 10:53:05 2011: Server recieved: 'Done' 
Fri Nov 18 10:53:05 2011: Server sending: 'Thanks' 
Fri Nov 18 10:53:05 2011: Finished Count: '11' 
Fri Nov 18 10:53:07 2011: Server recieved: 'Done' 
Fri Nov 18 10:53:07 2011: Server sending: 'Thanks' 
Fri Nov 18 10:53:07 2011: Finished Count: '12' 
Fri Nov 18 10:53:07 2011: All clients accounted for. Server ending, goodbye! 
[ 10:53 jon@hozbox.com ~/SO/python ]$ 

Answer 5

如果你

socket.bind(('localhost', RandomPort)) 

服務器計算機將只接受來自本身的連接，我。即本地主機。

相反，做

socket.bind(('', RandomPort)) 

監聽所有接口。