odd message from service

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noobizness's picture

I am calling Drupal XML-RPC services using Zend_XmlRpc_Client::call() and getting the following feedback:

as seen in the php error log:

[14-Jun-2010 19:26:38] Zend_XmlRpc_Client::call: cannot parse response: Zend_XmlRpc_Response Object
(
    [_return:protected] =>
    [_type:protected] =>
    [_encoding:protected] => UTF-8
    [_fault:protected] => Zend_XmlRpc_Fault Object
        (
            [_code:protected] => -32601
            [_encoding:protected] => UTF-8
            [_message:protected] => Server error. Requested method watchlist.get signature not specified.
            [_internal:protected] => Array
                (
                    [404] => Unknown Error
                    [610] => Invalid method class
            ... various local var's
                    [651] => Failed to parse response
                    [652] => Invalid response
                    [653] => Invalid XMLRPC value in response
                )

        )

)

The call IS GOING THROUGH - data is being sent to a custom function as spec'd in the service def - but the message is a little disconcerting. I don't know if this is even a Drupal thing - it could be a wierd Zend thing, but I was wondering if anyone else had context on this issue. what "signature" are they looking for and is Drupal expected to provide a signature? Any feedback would be appreciated.

FYI this is a call to a JSON xml-rpc service: the use of an XML-RPC class is probably an "inheritence thing".