| """Simple XML-RPC Server. |
| |
| 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 |
| class. |
| |
| It can also be used to handle XML-RPC requests in a CGI |
| environment using CGIXMLRPCRequestHandler. |
| |
| A list of possible usage patterns follows: |
| |
| 1. Install functions: |
| |
| server = SimpleXMLRPCServer(("localhost", 8000)) |
| server.register_function(pow) |
| server.register_function(lambda x,y: x+y, 'add') |
| server.serve_forever() |
| |
| 2. Install an instance: |
| |
| class MyFuncs: |
| def __init__(self): |
| # make all of the string functions available through |
| # string.func_name |
| import string |
| self.string = string |
| def _listMethods(self): |
| # implement this method so that system.listMethods |
| # knows to advertise the strings methods |
| return list_public_methods(self) + \ |
| ['string.' + method for method in list_public_methods(self.string)] |
| 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()) |
| server.serve_forever() |
| |
| 3. Install an instance with custom dispatch method: |
| |
| 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_instance(Math()) |
| server.serve_forever() |
| |
| 4. Subclass SimpleXMLRPCServer: |
| |
| class MathServer(SimpleXMLRPCServer): |
| def _dispatch(self, method, params): |
| try: |
| # We are forcing the 'export_' prefix on methods that are |
| # callable through XML-RPC to prevent potential security |
| # problems |
| func = getattr(self, 'export_' + method) |
| except AttributeError: |
| raise Exception('method "%s" is not supported' % method) |
| else: |
| return func(*params) |
| |
| def export_add(self, x, y): |
| return x + y |
| |
| server = MathServer(("localhost", 8000)) |
| server.serve_forever() |
| |
| 5. CGI script: |
| |
| server = CGIXMLRPCRequestHandler() |
| server.register_function(pow) |
| server.handle_request() |
| """ |
| |
| # Written by Brian Quinlan (brian@sweetapp.com). |
| # Based on code written by Fredrik Lundh. |
| |
| import xmlrpclib |
| from xmlrpclib import Fault |
| import SocketServer |
| import BaseHTTPServer |
| import sys |
| import os |
| |
| def resolve_dotted_attribute(obj, attr): |
| """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 '_'. |
| """ |
| |
| for i in attr.split('.'): |
| if i.startswith('_'): |
| raise AttributeError( |
| 'attempt to access private attribute "%s"' % i |
| ) |
| else: |
| obj = getattr(obj,i) |
| return obj |
| |
| 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))] |
| |
| def remove_duplicates(lst): |
| """remove_duplicates([2,2,2,1,3,3]) => [3,1,2] |
| |
| Returns a copy of a list without duplicates. Every list |
| item must be hashable and the order of the items in the |
| resulting list is not defined. |
| """ |
| u = {} |
| for x in lst: |
| u[x] = 1 |
| |
| return u.keys() |
| |
| 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. There should never be any |
| reason to instantiate this class directly. |
| """ |
| |
| def __init__(self): |
| self.funcs = {} |
| self.instance = None |
| |
| def register_instance(self, instance): |
| """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 |
| it's 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 |
| SimpleXMLRPCServer. |
| |
| If a registered function matches a XML-RPC request, then it |
| will be called instead of the registered instance. |
| """ |
| |
| self.instance = instance |
| |
| def register_function(self, function, name = None): |
| """Registers a function to respond to XML-RPC requests. |
| |
| The optional name argument can be used to set a Unicode name |
| for the function. |
| """ |
| |
| if name is None: |
| name = function.__name__ |
| self.funcs[name] = function |
| |
| def register_introspection_functions(self): |
| """Registers the XML-RPC introspection methods in the system |
| namespace. |
| |
| 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 |
| namespace. |
| |
| see http://www.xmlrpc.com/discuss/msgReader$1208""" |
| |
| self.funcs.update({'system.multicall' : self.system_multicall}) |
| |
| def _marshaled_dispatch(self, data, dispatch_method = 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 prefered means |
| of changing method dispatch behavior. |
| """ |
| |
| params, method = xmlrpclib.loads(data) |
| |
| # generate response |
| try: |
| if dispatch_method is not None: |
| response = dispatch_method(method, params) |
| else: |
| response = self._dispatch(method, params) |
| # wrap response in a singleton tuple |
| response = (response,) |
| response = xmlrpclib.dumps(response, methodresponse=1) |
| except Fault, fault: |
| response = xmlrpclib.dumps(fault) |
| except: |
| # report exception back to server |
| response = xmlrpclib.dumps( |
| xmlrpclib.Fault(1, "%s:%s" % (sys.exc_type, sys.exc_value)) |
| ) |
| |
| return response |
| |
| def system_listMethods(self): |
| """system.listMethods() => ['add', 'subtract', 'multiple'] |
| |
| Returns a list of the methods supported by the server.""" |
| |
| methods = self.funcs.keys() |
| if self.instance is not None: |
| # Instance can implement _listMethod to return a list of |
| # methods |
| if hasattr(self.instance, '_listMethods'): |
| methods = remove_duplicates( |
| methods + self.instance._listMethods() |
| ) |
| # if the instance has a _dispatch method then we |
| # don't have enough information to provide a list |
| # of methods |
| elif not hasattr(self.instance, '_dispatch'): |
| methods = remove_duplicates( |
| methods + list_public_methods(self.instance) |
| ) |
| methods.sort() |
| return methods |
| |
| def system_methodSignature(self, method_name): |
| """system.methodSignature('add') => [double, int, int] |
| |
| Returns a list describing the signiture 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.""" |
| |
| method = None |
| if self.funcs.has_key(method_name): |
| 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'): |
| try: |
| method = resolve_dotted_attribute( |
| self.instance, |
| method_name |
| ) |
| except AttributeError: |
| pass |
| |
| # Note that we aren't checking that the method actually |
| # be a callable object of some kind |
| if method is None: |
| return "" |
| else: |
| import pydoc |
| return pydoc.getdoc(method) |
| |
| def system_multicall(self, call_list): |
| """system.multicall([{'methodName': 'add', 'params': [2, 2]}, ...]) => \ |
| [[4], ...] |
| |
| Allows the caller to package multiple XML-RPC calls into a single |
| request. |
| |
| See http://www.xmlrpc.com/discuss/msgReader$1208 |
| """ |
| |
| results = [] |
| for call in call_list: |
| method_name = call['methodName'] |
| params = call['params'] |
| |
| try: |
| # 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)]) |
| except Fault, fault: |
| results.append( |
| {'faultCode' : fault.faultCode, |
| 'faultString' : fault.faultString} |
| ) |
| except: |
| results.append( |
| {'faultCode' : 1, |
| 'faultString' : "%s:%s" % (sys.exc_type, sys.exc_value)} |
| ) |
| return results |
| |
| 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 available. |
| |
| If the registered instance has a _dispatch method then that |
| method will be called with the name of the XML-RPC method and |
| it's 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. |
| """ |
| |
| func = None |
| try: |
| # check to see if a matching function has been registered |
| func = self.funcs[method] |
| except KeyError: |
| if self.instance is not None: |
| # check for a _dispatch method |
| if hasattr(self.instance, '_dispatch'): |
| return self.instance._dispatch(method, params) |
| else: |
| # call instance method directly |
| try: |
| func = resolve_dotted_attribute( |
| self.instance, |
| method |
| ) |
| except AttributeError: |
| pass |
| |
| if func is not None: |
| return func(*params) |
| else: |
| raise Exception('method "%s" is not supported' % method) |
| |
| class SimpleXMLRPCRequestHandler(BaseHTTPServer.BaseHTTPRequestHandler): |
| """Simple XML-RPC request handler class. |
| |
| Handles all HTTP POST requests and attempts to decode them as |
| XML-RPC requests. |
| """ |
| |
| def do_POST(self): |
| """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. |
| """ |
| |
| try: |
| # get arguments |
| data = self.rfile.read(int(self.headers["content-length"])) |
| # In previous versions of SimpleXMLRPCServer, _dispatch |
| # could be overridden in this class, instead of in |
| # SimpleXMLRPCDispatcher. To maintain backwards compatibility, |
| # check to see if a subclass implements _dispatch and dispatch |
| # using that method if present. |
| response = self.server._marshaled_dispatch( |
| data, getattr(self, '_dispatch', None) |
| ) |
| except: # This should only happen if the module is buggy |
| # internal error, report as HTTP server error |
| self.send_response(500) |
| self.end_headers() |
| else: |
| # got a valid XML RPC response |
| self.send_response(200) |
| self.send_header("Content-type", "text/xml") |
| self.send_header("Content-length", str(len(response))) |
| self.end_headers() |
| self.wfile.write(response) |
| |
| # shut down the connection |
| self.wfile.flush() |
| self.connection.shutdown(1) |
| |
| def log_request(self, code='-', size='-'): |
| """Selectively log an accepted request.""" |
| |
| if self.server.logRequests: |
| BaseHTTPServer.BaseHTTPRequestHandler.log_request(self, code, size) |
| |
| class SimpleXMLRPCServer(SocketServer.TCPServer, |
| SimpleXMLRPCDispatcher): |
| """Simple XML-RPC server. |
| |
| Simple XML-RPC server that allows functions and a single instance |
| to be installed to handle requests. The default implementation |
| attempts to dispatch XML-RPC calls to the functions or instance |
| installed in the server. Override the _dispatch method inhereted |
| from SimpleXMLRPCDispatcher to change this behavior. |
| """ |
| |
| def __init__(self, addr, requestHandler=SimpleXMLRPCRequestHandler, |
| logRequests=1): |
| self.logRequests = logRequests |
| |
| SimpleXMLRPCDispatcher.__init__(self) |
| SocketServer.TCPServer.__init__(self, addr, requestHandler) |
| |
| class CGIXMLRPCRequestHandler(SimpleXMLRPCDispatcher): |
| """Simple handler for XML-RPC data passed through CGI.""" |
| |
| def __init__(self): |
| SimpleXMLRPCDispatcher.__init__(self) |
| |
| def handle_xmlrpc(self, request_text): |
| """Handle a single XML-RPC request""" |
| |
| response = self._marshaled_dispatch(request_text) |
| |
| print 'Content-Type: text/xml' |
| print 'Content-Length: %d' % len(response) |
| print |
| sys.stdout.write(response) |
| |
| def handle_get(self): |
| """Handle a single HTTP GET request. |
| |
| Default implementation indicates an error because |
| XML-RPC uses the POST method. |
| """ |
| |
| code = 400 |
| message, explain = \ |
| BaseHTTPServer.BaseHTTPRequestHandler.responses[code] |
| |
| response = BaseHTTPServer.DEFAULT_ERROR_MESSAGE % \ |
| { |
| 'code' : code, |
| 'message' : message, |
| 'explain' : explain |
| } |
| print 'Status: %d %s' % (code, message) |
| print 'Content-Type: text/html' |
| print 'Content-Length: %d' % len(response) |
| print |
| sys.stdout.write(response) |
| |
| def handle_request(self, request_text = None): |
| """Handle a single XML-RPC request passed through a CGI post method. |
| |
| If no XML data is given then it is read from stdin. The resulting |
| XML-RPC response is printed to stdout along with the correct HTTP |
| headers. |
| """ |
| |
| if request_text is None and \ |
| os.environ.get('REQUEST_METHOD', None) == 'GET': |
| self.handle_get() |
| else: |
| # POST data is normally available through stdin |
| if request_text is None: |
| request_text = sys.stdin.read() |
| |
| self.handle_xmlrpc(request_text) |
| |
| if __name__ == '__main__': |
| server = SimpleXMLRPCServer(("localhost", 8000)) |
| server.register_function(pow) |
| server.register_function(lambda x,y: x+y, 'add') |
| server.serve_forever() |