Source code for libcloud.common.xmlrpc

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"""
Base classes for working with xmlrpc APIs
"""

import sys

from libcloud.utils.py3 import xmlrpclib
from libcloud.utils.py3 import httplib
from libcloud.common.base import Response, Connection


[docs]class ProtocolError(Exception): pass
[docs]class ErrorCodeMixin(object): """ This is a helper for API's that have a well defined collection of error codes that are easily parsed out of error messages. It acts as a factory: it finds the right exception for the error code, fetches any parameters it needs from the context and raises it. """ exceptions = {}
[docs] def raise_exception_for_error(self, error_code, message): exceptionCls = self.exceptions.get(error_code, None) if exceptionCls is None: return context = self.connection.context driver = self.connection.driver params = {} if hasattr(exceptionCls, 'kwargs'): for key in exceptionCls.kwargs: if key in context: params[key] = context[key] raise exceptionCls(value=message, driver=driver, **params)
[docs]class XMLRPCResponse(ErrorCodeMixin, Response): defaultExceptionCls = Exception
[docs] def success(self): return self.status == httplib.OK
[docs] def parse_body(self): try: params, methodname = xmlrpclib.loads(self.body) if len(params) == 1: params = params[0] return params except xmlrpclib.Fault: e = sys.exc_info()[1] self.raise_exception_for_error(e.faultCode, e.faultString) error_string = '%s: %s' % (e.faultCode, e.faultString) raise self.defaultExceptionCls(error_string)
[docs] def parse_error(self): msg = 'Server returned an invalid xmlrpc response (%d)' % (self.status) raise ProtocolError(msg)
[docs]class XMLRPCConnection(Connection): """ Connection class which can call XMLRPC based API's. This class uses the xmlrpclib marshalling and demarshalling code but uses the http transports provided by libcloud giving it better certificate validation and debugging helpers than the core client library. """ responseCls = XMLRPCResponse endpoint = None
[docs] def add_default_headers(self, headers): headers['Content-Type'] = 'text/xml' return headers
[docs] def request(self, method_name, *args, **kwargs): """ Call a given `method_name`. :type method_name: ``str`` :param method_name: A method exposed by the xmlrpc endpoint that you are connecting to. :type args: ``tuple`` :param args: Arguments to invoke with method with. """ endpoint = kwargs.get('endpoint', self.endpoint) data = xmlrpclib.dumps(args, methodname=method_name, allow_none=True) return super(XMLRPCConnection, self).request(endpoint, data=data, method='POST')