使用Python进行Socket文件传输

Question

我正在用Python通过套接字（sockets）构建一个简单的文件传输功能。可是我卡住了，似乎无法发送文件的任何部分。

根据一些建议，我尝试发送文件的最后一行，这样我就能知道什么时候可以结束连接。

但是问题是，一旦我发送了第一个数据包，客户端就再也收不到后面的内容了。

下面是我的代码（服务器端）：

import os
import socket
PORT = 8080
HOST = 'localhost'
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.bind((HOST,PORT))
socket.listen(10)
conn, addr = socket.accept()
print '\033[46m\033[34m\033[1mBienvenido al File Sender v.0.02 hecho en Python. Este         programa permite enviar archivos a traves de tu maquina\033[0m'
ANSI_RED = '\033[31m'
ANSI_BLUE = '\033[34m'
ESCAPEANSI = '\033[0m'
def seleccion_path():
PATH = raw_input('\033[34m\033[1mSelect the Path (./ by default)').strip('n')
if PATH == '':
    PATH = os.getcwd()   
print PATH, ESCAPEANSI
acepta_path = raw_input('\033[34m\033[1mSi o No (S/N)').lower().strip(' ')
if acepta_path == 's' or acepta_path == 'si':
    return PATH
else:
    seleccion_path()
def filesDir(path):
files = os.listdir(PATH)
for fl in files:
    i = int(files.index(fl))+1
    print ANSI_RED + str(i)+ ')' + fl
return files

PATH = seleccion_path()
print 'el PATH seleccionado es:', PATH + '\n'
filesDir(PATH)
fileSelected = int(raw_input(ANSI_BLUE + 'Select a file with the number').strip(' ').lower()) 
print PATH + filesDir(PATH)[fileSelected-1]
fileToSend = open(PATH + filesDir(PATH)[fileSelected-1], 'rb')
qLines = len(open(PATH + filesDir(PATH)[fileSelected-1], 'rb').readlines())

finalLine = cpfileToSend.readlines()[qLines-1]
conn.send(finalLine)
while True:
    data = conn.sendall(fileToSend.readline())
    conf = conn.recv(1024)
    print conf
    if conf == 'OK':
        conn.close()
        fileToSend.close()
         break
print '\033[43m File sent'
#Finaliza el programa y deja los codigos ANSI cerrados
print ESCAPEANSI
exit()

这是客户端的代码：

import os
import socket
PORT = 8080
HOST = 'localhost'

socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.connect((HOST, PORT))
fname = open('./fileSent.pdf', 'w+')

finalLine = socket.recv(1024)
print finalLine
while True:
    strng = socket.recv(2048)
    print 'aaaaa',strng
    fname.write(strng)
    if finalLine in strng:
        fname.write(strng)
        socket.send('OK')
        socket.close()
fname.close()
print 'Data received correctly' 
exit()

Answer 1

你的问题出在你打开文件后，使用 readlines 读取了所有的行，然后又试图在不关闭文件的情况下再次读取文件。

我也和 @T_12 一样好奇，为什么你想先发送文件的最后一行。不过假设你确实有这样的需求，这里有个解决办法：

把你服务器端代码中的这一部分替换掉（因为我没看到你定义 cpfileToSend 的地方，我猜它应该是 fileToSend）

fileToSend = open(PATH + filesDir(PATH)[fileSelected-1], 'rb')
qLines = len(open(PATH + filesDir(PATH)[fileSelected-1], 'rb').readlines())

finalLine = cpfileToSend.readlines()[qLines-1]
conn.send(finalLine)
while True:
    data = conn.sendall(fileToSend.readline())
    conf = conn.recv(1024)
    print conf
    if conf == 'OK':
        conn.close()
        fileToSend.close()
         break

换成这个

filepath = PATH + filesDir(PATH)[fileSelected-1]
fileToSend = open(filepath, 'rb')
qLines = len(open(PATH + filesDir(PATH)[fileSelected-1], 'rb').readlines())

finalLine = fileToSend.readlines()[qLines-1]
conn.send(finalLine)
fileToSend.close()
fileToSend = open(filepath, 'rb')
while True:
    data = conn.sendall(fileToSend.readline())
    conf = conn.recv(1024)
    print conf
    if conf == 'OK':
        conn.close()
        fileToSend.close()
         break

希望这能帮到你

Answer 2

最后我终于搞定了。问题出在socket.recv()上。我之前请求应用程序执行好几行代码，但服务器没有发送任何数据。客户端在那行代码之后就没继续执行，因为它在等着接收数据，以便继续运行后面的代码。

我调整了一下代码来解决这个问题，现在运行得很好。

我真心喜欢Python :)

服务器端：

import os
import socket
PORT = 8080
HOST = 'localhost'
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.bind((HOST,PORT))
socket.listen(1)
conn, addr = socket.accept()
print '\033[46m\033[34m\033[1mBienvenido al File Sender v.0.02 hecho en Python. Este programa permite enviar archivos a traves de tu maquina\033[0m'
ANSI_RED = '\033[31m'
ANSI_BLUE = '\033[34m'
ESCAPEANSI = '\033[0m'
def seleccion_path():
PATH = raw_input('\033[34m\033[1mSelect the Path (./ by default)').strip('n')
if PATH == '':
    PATH = os.getcwd()   
print PATH, ESCAPEANSI
acepta_path = raw_input('\033[34m\033[1mSi o No (S/N)').lower().strip(' ')
if acepta_path == 's' or acepta_path == 'si':
    return PATH
else:
    seleccion_path()
def filesDir(path):
files = os.listdir(PATH)
for fl in files:
    i = int(files.index(fl))+1
    print ANSI_RED + str(i)+ ')' + fl
return files

PATH = seleccion_path()
print 'el PATH seleccionado es:', PATH + '\n'
filesDir(PATH)
fileSelected = int(raw_input(ANSI_BLUE + 'Select a file with the number').strip(' ').lower()) 
print PATH + filesDir(PATH)[fileSelected-1]

filepath = PATH + filesDir(PATH)[fileSelected-1]
#envia nombre del file
conn.send(filepath)
qLines = len(open(PATH + filesDir(PATH)[fileSelected-1], 'rb').readlines())
fileToSend = open(filepath, 'rb')
while True:
data = fileToSend.readline()
if data:
    conn.send(data)
else:
    break
fileToSend.close()
conn.sendall('')
conn.close()

print '\033[43m File sent'  
#Finaliza el programa y deja los codigos ANSI cerrados
print ESCAPEANSI
exit()

客户端：

import os
import socket
PORT = 8080
HOST = 'localhost'

nombrearchivo = raw_input('define a name with its extension').strip(' ')
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.connect((HOST, PORT))
filename = socket.recv(1024)

fname = open('./'+nombrearchivo, 'wb')

while True:
strng = socket.recv(1024)
if strng:
    print strng
    fname.write(strng)
else:
    fname.close()
    break
socket.close()
print 'Data received correctly' 
exit()