Class Marshaller

Lib/xmlrpc/client.py:446–606

Generate an XML-RPC params chunk from a Python data structure. Create a Marshaller instance for each set of parameters, and use the "dumps" method to convert your data (represented as a tuple) to an XML-RPC params chunk. To write a fault response, pass a Fault instance instead. Yo

# @see dumps

class Marshaller:
    """Generate an XML-RPC params chunk from a Python data structure.

    Create a Marshaller instance for each set of parameters, and use
    the "dumps" method to convert your data (represented as a tuple)
    to an XML-RPC params chunk.  To write a fault response, pass a
    Fault instance instead.  You may prefer to use the "dumps" module
    function for this purpose.
    """

    # by the way, if you don't understand what's going on in here,
    # that's perfectly ok.

    def __init__(self, encoding=None, allow_none=False):
        self.memo = {}
        self.data = None
        self.encoding = encoding
        self.allow_none = allow_none

    dispatch = {}

    def dumps(self, values):
        out = []
        write = out.append
        dump = self.__dump
        if isinstance(values, Fault):
            # fault instance
            write("<fault>\n")
            dump({'faultCode': values.faultCode,
                  'faultString': values.faultString},
                 write)
            write("</fault>\n")
        else:
            # parameter block
            # FIXME: the xml-rpc specification allows us to leave out
            # the entire <params> block if there are no parameters.
            # however, changing this may break older code (including
            # old versions of xmlrpclib.py), so this is better left as
            # is for now.  See @XMLRPC3 for more information. /F
            write("<params>\n")
            for v in values:
                write("<param>\n")
                dump(v, write)
                write("</param>\n")
            write("</params>\n")
        result = "".join(out)
        return result

    def __dump(self, value, write):
        try:
            f = self.dispatch[type(value)]
        except KeyError:
            # check if this object can be marshalled as a structure
            if not hasattr(value, '__dict__'):
                raise TypeError("cannot marshal %s objects" % type(value))
            # check if this class is a sub-class of a basic type,
            # because we don't know how to marshal these types
            # (e.g. a string sub-class)