# # PLCAPI XML-RPC and SOAP interfaces # # Aaron Klingaman # Mark Huang # # Copyright (C) 2004-2006 The Trustees of Princeton University # import os import sys import traceback import string import xmlrpclib # See "2.2 Characters" in the XML specification: # # #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] # avoiding # [#x7F-#x84], [#x86-#x9F], [#xFDD0-#xFDDF] invalid_xml_ascii = map(chr, range(0x0, 0x8) + [0xB, 0xC] + range(0xE, 0x1F)) xml_escape_table = string.maketrans("".join(invalid_xml_ascii), "?" * len(invalid_xml_ascii)) def xmlrpclib_escape(s, replace = string.replace): """ xmlrpclib does not handle invalid 7-bit control characters. This function augments xmlrpclib.escape, which by default only replaces '&', '<', and '>' with entities. """ # This is the standard xmlrpclib.escape function s = replace(s, "&", "&") s = replace(s, "<", "<") s = replace(s, ">", ">",) # Replace invalid 7-bit control characters with '?' return s.translate(xml_escape_table) def xmlrpclib_dump(self, value, write): """ xmlrpclib cannot marshal instances of subclasses of built-in types. This function overrides xmlrpclib.Marshaller.__dump so that any value that is an instance of one of its acceptable types is marshalled as that type. xmlrpclib also cannot handle invalid 7-bit control characters. See above. """ # Use our escape function args = [self, value, write] if isinstance(value, (str, unicode)): args.append(xmlrpclib_escape) try: # Try for an exact match first f = self.dispatch[type(value)] except KeyError: # Try for an isinstance() match for Type, f in self.dispatch.iteritems(): if isinstance(value, Type): f(*args) return raise TypeError, "cannot marshal %s objects" % type(value) else: f(*args) # You can't hide from me! xmlrpclib.Marshaller._Marshaller__dump = xmlrpclib_dump # SOAP support is optional try: import SOAPpy from SOAPpy.Parser import parseSOAPRPC from SOAPpy.Types import faultType from SOAPpy.NS import NS from SOAPpy.SOAPBuilder import buildSOAP except ImportError: SOAPpy = None from PLC.Config import Config from PLC.Faults import * import PLC.Methods import PLC.Accessors def import_deep(name): mod = __import__(name) components = name.split('.') for comp in components[1:]: mod = getattr(mod, comp) return mod class PLCAPI: # flat list of method names native_methods = PLC.Methods.native_methods # other_methods_map : dict {methodname: fullpath} # e.g. 'Accessors' -> 'PLC.Accessors.Accessors' other_methods_map={} for subdir in [ 'Accessors' ]: path="PLC."+subdir # scan e.g. PLC.Accessors.__all__ pkg = __import__(path).__dict__[subdir] for modulename in getattr(pkg,"__all__"): fullpath=path+"."+modulename for method in getattr(import_deep(fullpath),"methods"): other_methods_map[method] = fullpath all_methods = native_methods + other_methods_map.keys() def __init__(self, config = "/etc/planetlab/plc_config", encoding = "utf-8"): self.encoding = encoding # Better just be documenting the API if config is None: return # Load configuration self.config = Config(config) # Initialize database connection if self.config.PLC_DB_TYPE == "postgresql": from PLC.PostgreSQL import PostgreSQL self.db = PostgreSQL(self) else: raise PLCAPIError, "Unsupported database type " + self.config.PLC_DB_TYPE # Aspects modify the API by injecting code before, after or # around method calls. -- http://github.com/baris/pyaspects/blob/master/README # if self.config.PLC_RATELIMIT_ENABLED: from aspects import apply_ratelimit_aspect apply_ratelimit_aspect() if getattr(self.config, "PLC_NETCONFIG_ENABLED", False): from aspects.netconfigaspects import apply_netconfig_aspect apply_netconfig_aspect() # Enable Caching. Only for GetSlivers for the moment. # TODO: we may consider to do this in an aspect like the ones above. try: if self.config.PLC_GETSLIVERS_CACHE: getslivers_cache = True except AttributeError: getslivers_cache = False if getslivers_cache: os.environ['DJANGO_SETTINGS_MODULE']='plc_django_settings' from cache_utils.decorators import cached from PLC.Methods.GetSlivers import GetSlivers @cached(7200) def cacheable_call(cls, auth, node_id_or_hostname): return cls.raw_call(auth, node_id_or_hostname) GetSlivers.call = cacheable_call def callable(self, method): """ Return a new instance of the specified method. """ # Look up method if method not in self.all_methods: raise PLCInvalidAPIMethod, method # Get new instance of method try: classname = method.split(".")[-1] if method in self.native_methods: fullpath="PLC.Methods." + method else: fullpath=self.other_methods_map[method] module = __import__(fullpath, globals(), locals(), [classname]) return getattr(module, classname)(self) except ImportError, AttributeError: raise PLCInvalidAPIMethod, "import error %s for %s" % (AttributeError,fullpath) def call(self, source, method, *args): """ Call the named method from the specified source with the specified arguments. """ function = self.callable(method) function.source = source return function(*args) def handle(self, source, data): """ Handle an XML-RPC or SOAP request from the specified source. """ # Parse request into method name and arguments try: interface = xmlrpclib (args, method) = xmlrpclib.loads(data) methodresponse = True except Exception, e: if SOAPpy is not None: interface = SOAPpy (r, header, body, attrs) = parseSOAPRPC(data, header = 1, body = 1, attrs = 1) method = r._name args = r._aslist() # XXX Support named arguments else: raise e try: result = self.call(source, method, *args) except PLCFault, fault: # Handle expected faults if interface == xmlrpclib: result = fault methodresponse = None elif interface == SOAPpy: result = faultParameter(NS.ENV_T + ":Server", "Method Failed", method) result._setDetail("Fault %d: %s" % (fault.faultCode, fault.faultString)) # Return result if interface == xmlrpclib: if not isinstance(result, PLCFault): result = (result,) data = xmlrpclib.dumps(result, methodresponse = True, encoding = self.encoding, allow_none = 1) elif interface == SOAPpy: data = buildSOAP(kw = {'%sResponse' % method: {'Result': result}}, encoding = self.encoding) return data def handle_json(self, source, data): """ Handle a JSON request """ method, args = json.loads(data) try: result = self.call(source, method, *args) except Exception, e: result = str(e) return json.dumps(result)