"xmlrpc.server" --- 基本 XML-RPC 服务器
***************************************

**源代码:** Lib/xmlrpc/server.py

======================================================================

The "xmlrpc.server" module provides a basic server framework for XML-
RPC servers written in Python.  Servers can either be free standing,
using "SimpleXMLRPCServer", or embedded in a CGI environment, using
"CGIXMLRPCRequestHandler".

警告:

  The "xmlrpc.server" module is not secure against maliciously
  constructed data.  If you need to parse untrusted or unauthenticated
  data see XML 漏洞.

class xmlrpc.server.SimpleXMLRPCServer(addr, requestHandler=SimpleXMLRPCRequestHandler, logRequests=True, allow_none=False, encoding=None, bind_and_activate=True, use_builtin_types=False)

   Create a new server instance.  This class provides methods for
   registration of functions that can be called by the XML-RPC
   protocol.  The *requestHandler* parameter should be a factory for
   request handler instances; it defaults to
   "SimpleXMLRPCRequestHandler".  The *addr* and *requestHandler*
   parameters are passed to the "socketserver.TCPServer" constructor.
   If *logRequests* is true (the default), requests will be logged;
   setting this parameter to false will turn off logging.   The
   *allow_none* and *encoding* parameters are passed on to
   "xmlrpc.client" and control the XML-RPC responses that will be
   returned from the server. The *bind_and_activate* parameter
   controls whether "server_bind()" and "server_activate()" are called
   immediately by the constructor; it defaults to true. Setting it to
   false allows code to manipulate the *allow_reuse_address* class
   variable before the address is bound. The *use_builtin_types*
   parameter is passed to the "loads()" function and controls which
   types are processed when date/times values or binary data are
   received; it defaults to false.

   3.3 版更變: The *use_builtin_types* flag was added.

class xmlrpc.server.CGIXMLRPCRequestHandler(allow_none=False, encoding=None, use_builtin_types=False)

   Create a new instance to handle XML-RPC requests in a CGI
   environment.  The *allow_none* and *encoding* parameters are passed
   on to "xmlrpc.client" and control the XML-RPC responses that will
   be returned from the server. The *use_builtin_types* parameter is
   passed to the "loads()" function and controls which types are
   processed when date/times values or binary data are received; it
   defaults to false.

   3.3 版更變: The *use_builtin_types* flag was added.

class xmlrpc.server.SimpleXMLRPCRequestHandler

   Create a new request handler instance.  This request handler
   supports "POST" requests and modifies logging so that the
   *logRequests* parameter to the "SimpleXMLRPCServer" constructor
   parameter is honored.


SimpleXMLRPCServer Objects
==========================

The "SimpleXMLRPCServer" class is based on "socketserver.TCPServer"
and provides a means of creating simple, stand alone XML-RPC servers.

SimpleXMLRPCServer.register_function(function=None, name=None)

   Register a function that can respond to XML-RPC requests.  If
   *name* is given, it will be the method name associated with
   *function*, otherwise "function.__name__" will be used.  *name* is
   a string, and may contain characters not legal in Python
   identifiers, including the period character.

   This method can also be used as a decorator.  When used as a
   decorator, *name* can only be given as a keyword argument to
   register *function* under *name*.  If no *name* is given,
   "function.__name__" will be used.

   3.7 版更變: "register_function()" can be used as a decorator.

SimpleXMLRPCServer.register_instance(instance, allow_dotted_names=False)

   Register an object which is used to expose method names which have
   not been registered using "register_function()".  If *instance*
   contains a "_dispatch()" method, it is called with the requested
   method name and the parameters from the request.  Its API is "def
   _dispatch(self, method, params)" (note that *params* does not
   represent a variable argument list).  If it calls an underlying
   function to perform its task, that function is called as
   "func(*params)", expanding the parameter list. The return value
   from "_dispatch()" is returned to the client as the result.  If
   *instance* does not have a "_dispatch()" method, it is searched for
   an attribute matching the name of the requested method.

   If the optional *allow_dotted_names* argument is true and the
   instance does not have a "_dispatch()" method, then if the
   requested method name contains periods, each component of the
   method name is searched for individually, with the effect that a
   simple hierarchical search is performed.  The value found from this
   search is then called with the parameters from the request, and the
   return value is passed back to the client.

   警告:

     Enabling the *allow_dotted_names* option allows intruders to
     access your module's global variables and may allow intruders to
     execute arbitrary code on your machine.  Only use this option on
     a secure, closed network.

SimpleXMLRPCServer.register_introspection_functions()

   Registers the XML-RPC introspection functions "system.listMethods",
   "system.methodHelp" and "system.methodSignature".

SimpleXMLRPCServer.register_multicall_functions()

   Registers the XML-RPC multicall function system.multicall.

SimpleXMLRPCRequestHandler.rpc_paths

   An attribute value that must be a tuple listing valid path portions
   of the URL for receiving XML-RPC requests.  Requests posted to
   other paths will result in a 404 "no such page" HTTP error.  If
   this tuple is empty, all paths will be considered valid. The
   default value is "('/', '/RPC2')".


SimpleXMLRPCServer Example
--------------------------

Server code:

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

   # Restrict to a particular path.
   class RequestHandler(SimpleXMLRPCRequestHandler):
       rpc_paths = ('/RPC2',)

   # Create server
   with SimpleXMLRPCServer(('localhost', 8000),
                           requestHandler=RequestHandler) as server:
       server.register_introspection_functions()

       # Register pow() function; this will use the value of
       # pow.__name__ as the name, which is just 'pow'.
       server.register_function(pow)

       # Register a function under a different name
       def adder_function(x, y):
           return x + y
       server.register_function(adder_function, 'add')

       # Register an instance; all the methods of the instance are
       # published as XML-RPC methods (in this case, just 'mul').
       class MyFuncs:
           def mul(self, x, y):
               return x * y

       server.register_instance(MyFuncs())

       # Run the server's main loop
       server.serve_forever()

The following client code will call the methods made available by the
preceding server:

   import xmlrpc.client

   s = xmlrpc.client.ServerProxy('http://localhost:8000')
   print(s.pow(2,3))  # Returns 2**3 = 8
   print(s.add(2,3))  # Returns 5
   print(s.mul(5,2))  # Returns 5*2 = 10

   # Print list of available methods
   print(s.system.listMethods())

"register_function()" can also be used as a decorator. The previous
server example can register functions in a decorator way:

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

   class RequestHandler(SimpleXMLRPCRequestHandler):
       rpc_paths = ('/RPC2',)

   with SimpleXMLRPCServer(('localhost', 8000),
                           requestHandler=RequestHandler) as server:
       server.register_introspection_functions()

       # Register pow() function; this will use the value of
       # pow.__name__ as the name, which is just 'pow'.
       server.register_function(pow)

       # Register a function under a different name, using
       # register_function as a decorator. *name* can only be given
       # as a keyword argument.
       @server.register_function(name='add')
       def adder_function(x, y):
           return x + y

       # Register a function under function.__name__.
       @server.register_function
       def mul(x, y):
           return x * y

       server.serve_forever()

The following example included in the "Lib/xmlrpc/server.py" module
shows a server allowing dotted names and registering a multicall
function.

警告:

  Enabling the *allow_dotted_names* option allows intruders to access
  your module's global variables and may allow intruders to execute
  arbitrary code on your machine.  Only use this example only within a
  secure, closed network.

   import datetime

   class ExampleService:
       def getData(self):
           return '42'

       class currentTime:
           @staticmethod
           def getCurrentTime():
               return datetime.datetime.now()

   with SimpleXMLRPCServer(("localhost", 8000)) as server:
       server.register_function(pow)
       server.register_function(lambda x,y: x+y, 'add')
       server.register_instance(ExampleService(), allow_dotted_names=True)
       server.register_multicall_functions()
       print('Serving XML-RPC on localhost port 8000')
       try:
           server.serve_forever()
       except KeyboardInterrupt:
           print("\nKeyboard interrupt received, exiting.")
           sys.exit(0)

This ExampleService demo can be invoked from the command line:

   python -m xmlrpc.server

The client that interacts with the above server is included in
*Lib/xmlrpc/client.py*:

   server = ServerProxy("http://localhost:8000")

   try:
       print(server.currentTime.getCurrentTime())
   except Error as v:
       print("ERROR", v)

   multi = MultiCall(server)
   multi.getData()
   multi.pow(2,9)
   multi.add(1,2)
   try:
       for response in multi():
           print(response)
   except Error as v:
       print("ERROR", v)

This client which interacts with the demo XMLRPC server can be invoked
as:

   python -m xmlrpc.client


CGIXMLRPCRequestHandler
=======================

The "CGIXMLRPCRequestHandler" class can be used to handle XML-RPC
requests sent to Python CGI scripts.

CGIXMLRPCRequestHandler.register_function(function=None, name=None)

   Register a function that can respond to XML-RPC requests.  If
   *name* is given, it will be the method name associated with
   *function*, otherwise "function.__name__" will be used.  *name* is
   a string, and may contain characters not legal in Python
   identifiers, including the period character.

   This method can also be used as a decorator.  When used as a
   decorator, *name* can only be given as a keyword argument to
   register *function* under *name*.  If no *name* is given,
   "function.__name__" will be used.

   3.7 版更變: "register_function()" can be used as a decorator.

CGIXMLRPCRequestHandler.register_instance(instance)

   Register an object which is used to expose method names  which have
   not been registered using "register_function()". If  instance
   contains a "_dispatch()" method, it is called with the  requested
   method name and the parameters from the  request; the return value
   is returned to the client as the result. If instance does not have
   a "_dispatch()" method, it is searched for an attribute matching
   the name of the requested method; if  the requested method name
   contains periods, each  component of the method name is searched
   for individually,  with the effect that a simple hierarchical
   search is performed. The value found from this search is then
   called with the  parameters from the request, and the return value
   is passed  back to the client.

CGIXMLRPCRequestHandler.register_introspection_functions()

   Register the XML-RPC introspection functions  "system.listMethods",
   "system.methodHelp" and  "system.methodSignature".

CGIXMLRPCRequestHandler.register_multicall_functions()

   Register the XML-RPC multicall function "system.multicall".

CGIXMLRPCRequestHandler.handle_request(request_text=None)

   Handle an XML-RPC request. If *request_text* is given, it should be
   the POST data provided by the HTTP server,  otherwise the contents
   of stdin will be used.

示例:

   class MyFuncs:
       def mul(self, x, y):
           return x * y


   handler = CGIXMLRPCRequestHandler()
   handler.register_function(pow)
   handler.register_function(lambda x,y: x+y, 'add')
   handler.register_introspection_functions()
   handler.register_instance(MyFuncs())
   handler.handle_request()


Documenting XMLRPC server
=========================

These classes extend the above classes to serve HTML documentation in
response to HTTP GET requests.  Servers can either be free standing,
using "DocXMLRPCServer", or embedded in a CGI environment, using
"DocCGIXMLRPCRequestHandler".

class xmlrpc.server.DocXMLRPCServer(addr, requestHandler=DocXMLRPCRequestHandler, logRequests=True, allow_none=False, encoding=None, bind_and_activate=True, use_builtin_types=True)

   Create a new server instance. All parameters have the same meaning
   as for "SimpleXMLRPCServer"; *requestHandler* defaults to
   "DocXMLRPCRequestHandler".

   3.3 版更變: The *use_builtin_types* flag was added.

class xmlrpc.server.DocCGIXMLRPCRequestHandler

   Create a new instance to handle XML-RPC requests in a CGI
   environment.

class xmlrpc.server.DocXMLRPCRequestHandler

   Create a new request handler instance. This request handler
   supports XML-RPC POST requests, documentation GET requests, and
   modifies logging so that the *logRequests* parameter to the
   "DocXMLRPCServer" constructor parameter is honored.


DocXMLRPCServer Objects
=======================

The "DocXMLRPCServer" class is derived from "SimpleXMLRPCServer" and
provides a means of creating self-documenting, stand alone XML-RPC
servers. HTTP POST requests are handled as XML-RPC method calls. HTTP
GET requests are handled by generating pydoc-style HTML documentation.
This allows a server to provide its own web-based documentation.

DocXMLRPCServer.set_server_title(server_title)

   Set the title used in the generated HTML documentation. This title
   will be used inside the HTML "title" element.

DocXMLRPCServer.set_server_name(server_name)

   Set the name used in the generated HTML documentation. This name
   will appear at the top of the generated documentation inside a "h1"
   element.

DocXMLRPCServer.set_server_documentation(server_documentation)

   Set the description used in the generated HTML documentation. This
   description will appear as a paragraph, below the server name, in
   the documentation.


DocCGIXMLRPCRequestHandler
==========================

The "DocCGIXMLRPCRequestHandler" class is derived from
"CGIXMLRPCRequestHandler" and provides a means of creating self-
documenting, XML-RPC CGI scripts. HTTP POST requests are handled as
XML-RPC method calls. HTTP GET requests are handled by generating
pydoc-style HTML documentation. This allows a server to provide its
own web-based documentation.

DocCGIXMLRPCRequestHandler.set_server_title(server_title)

   Set the title used in the generated HTML documentation. This title
   will be used inside the HTML "title" element.

DocCGIXMLRPCRequestHandler.set_server_name(server_name)

   Set the name used in the generated HTML documentation. This name
   will appear at the top of the generated documentation inside a "h1"
   element.

DocCGIXMLRPCRequestHandler.set_server_documentation(server_documentation)

   Set the description used in the generated HTML documentation. This
   description will appear as a paragraph, below the server name, in
   the documentation.
