This module can be used to create simple XML-RPC servers
by creating a server and either installing functions, a
class instance, or by extending the SimpleXMLRPCServer
It can also be used to handle XML-RPC requests in a CGI
environment using CGIXMLRPCRequestHandler.
The Doc* classes can be used to create XML-RPC servers that
serve pydoc-style documentation in response to HTTP
GET requests. This documentation is dynamically generated
based on the functions and methods registered with the
A list of possible usage patterns follows:
server = SimpleXMLRPCServer(("localhost", 8000))
server.register_function(pow)
server.register_function(lambda x,y: x+y, 'add')
# make all of the sys functions available through sys.func_name
# implement this method so that system.listMethods
# knows to advertise the sys methods
return list_public_methods(self) + \
['sys.' + method for method in list_public_methods(self.sys)]
def pow(self, x, y): return pow(x, y)
def add(self, x, y) : return x + y
server = SimpleXMLRPCServer(("localhost", 8000))
server.register_introspection_functions()
server.register_instance(MyFuncs())
3. Install an instance with custom dispatch method:
# this method must be present for system.listMethods
def _methodHelp(self, method):
# this method must be present for system.methodHelp
return "pow(x, y[, z]) => number"
# By convention, return empty
# string if no help is available
def _dispatch(self, method, params):
return params[0] + params[1]
raise ValueError('bad method')
server = SimpleXMLRPCServer(("localhost", 8000))
server.register_introspection_functions()
server.register_instance(Math())
4. Subclass SimpleXMLRPCServer:
class MathServer(SimpleXMLRPCServer):
def _dispatch(self, method, params):
# We are forcing the 'export_' prefix on methods that are
# callable through XML-RPC to prevent potential security
func = getattr(self, 'export_' + method)
raise Exception('method "%s" is not supported' % method)
def export_add(self, x, y):
server = MathServer(("localhost", 8000))
server = CGIXMLRPCRequestHandler()
server.register_function(pow)
# Written by Brian Quinlan (brian@sweetapp.com).
# Based on code written by Fredrik Lundh.
from xmlrpc.client import Fault, dumps, loads, gzip_encode, gzip_decode
from http.server import BaseHTTPRequestHandler
from functools import partial
from inspect import signature
def resolve_dotted_attribute(obj, attr, allow_dotted_names=True):
"""resolve_dotted_attribute(a, 'b.c.d') => a.b.c.d
Resolves a dotted attribute name to an object. Raises
an AttributeError if any attribute in the chain starts with a '_'.
If the optional allow_dotted_names argument is false, dots are not
supported and this function operates similar to getattr(obj, attr).
'attempt to access private attribute "%s"' % i
def list_public_methods(obj):
"""Returns a list of attribute strings, found in the specified
object, which represent callable attributes"""
return [member for member in dir(obj)
if not member.startswith('_') and
callable(getattr(obj, member))]
class SimpleXMLRPCDispatcher:
"""Mix-in class that dispatches XML-RPC requests.
This class is used to register XML-RPC method handlers
and then to dispatch them. This class doesn't need to be
instanced directly when used by SimpleXMLRPCServer but it
can be instanced when used by the MultiPathXMLRPCServer
def __init__(self, allow_none=False, encoding=None,
use_builtin_types=False):
self.allow_none = allow_none
self.encoding = encoding or 'utf-8'
self.use_builtin_types = use_builtin_types
def register_instance(self, instance, allow_dotted_names=False):
"""Registers an instance to respond to XML-RPC requests.
Only one instance can be installed at a time.
If the registered instance has a _dispatch method then that
method will be called with the name of the XML-RPC method and
its parameters as a tuple
e.g. instance._dispatch('add',(2,3))
If the registered instance does not have a _dispatch method
then the instance will be searched to find a matching method
and, if found, will be called. Methods beginning with an '_'
are considered private and will not be called by
If a registered function matches an XML-RPC request, then it
will be called instead of the registered instance.
If the optional allow_dotted_names argument is true and the
instance does not have a _dispatch method, method names
containing dots are supported and resolved, as long as none of
the name segments start with an '_'.
*** SECURITY WARNING: ***
Enabling the allow_dotted_names options 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.
self.allow_dotted_names = allow_dotted_names
def register_function(self, function=None, name=None):
"""Registers a function to respond to XML-RPC requests.
The optional name argument can be used to set a Unicode name
return partial(self.register_function, name=name)
self.funcs[name] = function
def register_introspection_functions(self):
"""Registers the XML-RPC introspection methods in the system
see http://xmlrpc.usefulinc.com/doc/reserved.html
self.funcs.update({'system.listMethods' : self.system_listMethods,
'system.methodSignature' : self.system_methodSignature,
'system.methodHelp' : self.system_methodHelp})
def register_multicall_functions(self):
"""Registers the XML-RPC multicall method in the system
see http://www.xmlrpc.com/discuss/msgReader$1208"""
self.funcs.update({'system.multicall' : self.system_multicall})
def _marshaled_dispatch(self, data, dispatch_method = None, path = None):
"""Dispatches an XML-RPC method from marshalled (XML) data.
XML-RPC methods are dispatched from the marshalled (XML) data
using the _dispatch method and the result is returned as
marshalled data. For backwards compatibility, a dispatch
function can be provided as an argument (see comment in
SimpleXMLRPCRequestHandler.do_POST) but overriding the
existing method through subclassing is the preferred means
of changing method dispatch behavior.
params, method = loads(data, use_builtin_types=self.use_builtin_types)
if dispatch_method is not None:
response = dispatch_method(method, params)
response = self._dispatch(method, params)
# wrap response in a singleton tuple
response = dumps(response, methodresponse=1,
allow_none=self.allow_none, encoding=self.encoding)
response = dumps(fault, allow_none=self.allow_none,
# report exception back to server
exc_type, exc_value, exc_tb = sys.exc_info()
Fault(1, "%s:%s" % (exc_type, exc_value)),
encoding=self.encoding, allow_none=self.allow_none,
exc_type = exc_value = exc_tb = None
return response.encode(self.encoding, 'xmlcharrefreplace')
def system_listMethods(self):
"""system.listMethods() => ['add', 'subtract', 'multiple']
Returns a list of the methods supported by the server."""
methods = set(self.funcs.keys())
if self.instance is not None:
# Instance can implement _listMethod to return a list of
if hasattr(self.instance, '_listMethods'):
methods |= set(self.instance._listMethods())
# if the instance has a _dispatch method then we
# don't have enough information to provide a list
elif not hasattr(self.instance, '_dispatch'):
methods |= set(list_public_methods(self.instance))
def system_methodSignature(self, method_name):
"""system.methodSignature('add') => [double, int, int]
Returns a list describing the signature of the method. In the
above example, the add method takes two integers as arguments
and returns a double result.
This server does NOT support system.methodSignature."""
# See http://xmlrpc.usefulinc.com/doc/sysmethodsig.html
return 'signatures not supported'
def system_methodHelp(self, method_name):
"""system.methodHelp('add') => "Adds two integers together"
Returns a string containing documentation for the specified method."""
if method_name in self.funcs:
method = self.funcs[method_name]
elif self.instance is not None:
# Instance can implement _methodHelp to return help for a method
if hasattr(self.instance, '_methodHelp'):
return self.instance._methodHelp(method_name)
# if the instance has a _dispatch method then we
# don't have enough information to provide help
elif not hasattr(self.instance, '_dispatch'):
method = resolve_dotted_attribute(
# Note that we aren't checking that the method actually
# be a callable object of some kind
return pydoc.getdoc(method)
def system_multicall(self, call_list):
"""system.multicall([{'methodName': 'add', 'params': [2, 2]}, ...]) => \
Allows the caller to package multiple XML-RPC calls into a single
See http://www.xmlrpc.com/discuss/msgReader$1208
method_name = call['methodName']
# XXX A marshalling error in any response will fail the entire
# multicall. If someone cares they should fix this.
results.append([self._dispatch(method_name, params)])
{'faultCode' : fault.faultCode,
'faultString' : fault.faultString}
exc_type, exc_value, exc_tb = sys.exc_info()
'faultString' : "%s:%s" % (exc_type, exc_value)}
exc_type = exc_value = exc_tb = None
def _dispatch(self, method, params):
"""Dispatches the XML-RPC method.
XML-RPC calls are forwarded to a registered function that
matches the called XML-RPC method name. If no such function
exists then the call is forwarded to the registered instance,
If the registered instance has a _dispatch method then that
method will be called with the name of the XML-RPC method and
its parameters as a tuple
e.g. instance._dispatch('add',(2,3))
If the registered instance does not have a _dispatch method
then the instance will be searched to find a matching method
and, if found, will be called.
Methods beginning with an '_' are considered private and will
# call the matching registered function
func = self.funcs[method]
raise Exception('method "%s" is not supported' % method)
if self.instance is not None:
if hasattr(self.instance, '_dispatch'):
# call the `_dispatch` method on the instance
return self.instance._dispatch(method, params)
# call the instance's method directly
func = resolve_dotted_attribute(
raise Exception('method "%s" is not supported' % method)
class SimpleXMLRPCRequestHandler(BaseHTTPRequestHandler):
"""Simple XML-RPC request handler class.
Handles all HTTP POST requests and attempts to decode them as
# Class attribute listing the accessible path components;
# paths not on this list will result in a 404 error.
rpc_paths = ('/', '/RPC2')
#if not None, encode responses larger than this, if possible
encode_threshold = 1400 #a common MTU
#Override form StreamRequestHandler: full buffering of output
disable_nagle_algorithm = True
# a re to match a gzip Accept-Encoding
aepattern = re.compile(r"""
\s* ([^\s;]+) \s* #content-coding
(;\s* q \s*=\s* ([0-9\.]+))? #q
""", re.VERBOSE | re.IGNORECASE)
def accept_encodings(self):
ae = self.headers.get("Accept-Encoding", "")
match = self.aepattern.match(e)
v = float(v) if v else 1.0
def is_rpc_path_valid(self):
return self.path in self.rpc_paths
# If .rpc_paths is empty, just assume all paths are legal
"""Handles the HTTP POST request.
Attempts to interpret all HTTP POST requests as XML-RPC calls,
which are forwarded to the server's _dispatch method for handling.
# Check that the path is legal
if not self.is_rpc_path_valid():
# Get arguments by reading body of request.
# We read this in chunks to avoid straining
# socket.read(); around the 10 or 15Mb mark, some platforms
# begin to have problems (bug #792570).
max_chunk_size = 10*1024*1024
size_remaining = int(self.headers["content-length"])
chunk_size = min(size_remaining, max_chunk_size)
chunk = self.rfile.read(chunk_size)