python类库31[XML RPC实例]

一 远程过程调用RPC 

XML-RPC is a Remote Procedure Call method that uses XML passed via HTTP as a transport. With it, a client can call methods with parameters on a remote server (the server is named by a URI) and get back structured data. This module supports writing XML-RPC client code; it handles all the details of translating between conformable Python objects and XML on the wire.

简单地，client可以调用server上提供的方法，然后得到执行的结果。类似与webservice。

推荐查看xmlprc的源文件：C:\Python31\Lib\xmlrpc

二 实例

1） Server

from xmlrpc.server import SimpleXMLRPCServer
from xmlrpc.server import SimpleXMLRPCRequestHandler

def div(x,y):
    return x - y
    
class Math:
    def _listMethods(self):
        # this method must be present for system.listMethods
        # to work
        return ['add', 'pow']
    def _methodHelp(self, method):
        # this method must be present for system.methodHelp
        # to work
        if method == 'add':
            return "add(2,3) => 5"
        elif method == 'pow':
            return "pow(x, y[, z]) => number"
        else:
            # By convention, return empty
            # string if no help is available
            return ""
    def _dispatch(self, method, params):
        if method == 'pow':
            return pow(*params)
        elif method == 'add':
            return params[0] + params[1]
        else:
            raise 'bad method'

server = SimpleXMLRPCServer(("localhost", 8000))
server.register_introspection_functions()
server.register_function(div,"div")
server.register_function(lambda x,y: x*y, 'multiply')
server.register_instance(Math())
server.serve_forever()

2）client

import xmlrpc.client

s = xmlrpc.client.ServerProxy('http://localhost:8000')

print(s.system.listMethods())

print(s.pow(2,3))  # Returns 28
print(s.add(2,3))  # Returns 5
print(s.div(3,2))  # Returns 1
print(s.multiply(4,5)) # Returns 20

3）result

完！