python - 在 Python 中使用 XMLRPC 时，尽管添加了allow_none=True，但仍出现错误 "cannot marshal None"

Question

我尝试在 Python 中使用 XMLRPC 创建一个简单的下载和上传系统

这是客户端的代码(将此文件命名为client.py)

import sys
import xmlrpclib
import os

def return_pause():
    """Used for creating a pause during input"""

    raw_input("\n\tPress enter to continue")

def mod_file_download(file_name, local_port, remote_proxy, local_proxy):
    """Sending details to remote node which will send file to local node"""

    #print "till here"

    #print "{%s}\t{%s}" % (file_name,local_proxy)

    remote_proxy.mod_file_transfer(file_name, local_proxy)

def mod_file_upload(file_path, file_name, remote_proxy):
    """Used for sending files to a receiver. Sent file will always have the name file_1.txt"""

    new_file_name = "file_1.txt"
    with open(file_path, "rb") as handle:
        bin_data = xmlrpclib.Binary(handle.read())

    remote_proxy.mod_file_receive(bin_data, new_file_name)

    return True

##MAIN MODULE STARTS HERE##

# Connection details of remote node
local_port = sys.argv[1]

# Getting details of remote node
remote_port = raw_input("\n\tEnter remote port ID : ")

# Creating connection details of remote node
remote_proxy = xmlrpclib.ServerProxy("http://localhost:" + remote_port + "/")

# Creating connection details of local node
local_proxy = xmlrpclib.ServerProxy("http://localhost:" + local_port + "/")

while True:
    os.system('clear')

    print "\t. : Collab Menu for %s : .\n" % local_port
    print "\tSearch & download ...[1]"
    print "\tUpload            ...[2]"
    print "\tExit              ...[0]"

    input_val = raw_input("\n\n\tEnter option : ")

    if input_val == "1":
        file_name = raw_input("\n\tEnter name of file to be downloaded : ")

        mod_file_download(file_name, local_port, remote_proxy, local_proxy)

        return_pause()

    elif input_val == "2":
        file_name = raw_input("\n\tEnter name of file to be uploaded : ")

        file_path = "./" + file_name

        mod_file_upload(file_path, file_name, remote_proxy, local_proxy)

        return_pause()

    elif input_val == "0":
        print "\tExiting"
        break

    else:
        print "\tIncorrect option value"
        print "\tTry again..."
        return_pause()

os.system('clear')

这是监听器的代码(将此文件命名为listener.py)

import sys
import xmlrpclib
from SimpleXMLRPCServer import SimpleXMLRPCServer

def mod_file_transfer(file_name, requestor_proxy):
    """Initiating the file transfer"""

    print "[mod_file_transfer fired]"

    file_path = "./" + file_name

    print requestor_proxy

    with open(file_path, "rb") as handle:
        bin_data = xmlrpclib.Binary(handle.read())

    # Connecting to requestor's server
    requestor_proxy.mod_file_download_receive(bin_data, file_name)

    return True

def mod_file_receive(bin_data, file_name):
    """Used to receive a file upon a request of an upload"""

    print "[mod_file_receive fired]"

    new_file_name = "./" + file_name
    with open(new_file_name, "wb") as handle:
        handle.write(bin_data.data)
        return True

def mod_file_download_receive(bin_data, file_name):
    """Used to receive a file upon request of a download"""

    print "[mod_file_download_receive fired]"

    new_file_name = "./" + file_name + str(1)
    with open(new_file_name, "wb") as handle:
        handle.write(bin_data.data)
        return True

##MAIN MODULE STARTS HERE##

local_port = sys.argv[1]

# Declared an XMLRPC server
node = SimpleXMLRPCServer(("localhost", int(local_port)), logRequests=True, allow_none=True)
print "Listening on port %s..." % local_port

# Registered a list of functions
node.register_function(mod_file_transfer, 'mod_file_transfer')
node.register_function(mod_file_receive, 'mod_file_receive')
node.register_function(mod_file_download_receive, 'mod_file_download_receive')

# Initialized the XMLRPC server
node.serve_forever()

如何启动系统？

1. 将两个文件放在同一目录中
2. 执行以下命令
3. python 监听器 9000
4. python 监听器 9500
5. python 客户端 9000(然后将远程客户端端口指定为 9500 作为输入)
6. python 客户端 9500(然后将远程客户端端口指定为 9000 作为输入)

文件上传工作正常

但是文件下载不起作用

它给了我以下错误

Traceback (most recent call last):
  File "collab_client.py", line 57, in <module>
    mod_file_download(file_name, local_port, remote_proxy, local_proxy)
  File "collab_client.py", line 17, in mod_file_download
    remote_proxy.mod_file_transfer(file_name, local_proxy)
  File "/usr/lib/python2.7/xmlrpclib.py", line 1240, in __call__
    return self.__send(self.__name, args)
  File "/usr/lib/python2.7/xmlrpclib.py", line 1593, in __request
    allow_none=self.__allow_none)
  File "/usr/lib/python2.7/xmlrpclib.py", line 1091, in dumps
    data = m.dumps(params)
  File "/usr/lib/python2.7/xmlrpclib.py", line 638, in dumps
    dump(v, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 660, in __dump
    f(self, value, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 762, in dump_instance
    self.dump_struct(value.__dict__, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 741, in dump_struct
    dump(v, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 660, in __dump
    f(self, value, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 762, in dump_instance
    self.dump_struct(value.__dict__, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 741, in dump_struct
    dump(v, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 660, in __dump
    f(self, value, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 720, in dump_array
    dump(v, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 660, in __dump
    f(self, value, write)
  File "/usr/lib/python2.7/xmlrpclib.py", line 664, in dump_nil
    raise TypeError, "cannot marshal None unless allow_none is enabled"
TypeError: cannot marshal None unless allow_none is enabled

但我已经在监听器文件中提供了选项allow_none=True。

我哪里出错了？

Answer 1

我在很头疼之后发现了它。似乎无法发送或编码连接详细信息。在函数 mod_file_transfer 中，我尝试将客户端连接详细信息作为对象发送(以便服务器知道必须将文件发送给谁)，这导致了错误。

我只是将客户端连接详细信息作为字符串发送，它就起作用了。谢谢我!