#!/usr/bin/env python

# Authors:
#   Rob Crittenden <rcritten@redhat.com>
#
# Copyright (C) 2008  Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; version 2 only
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

"""
In-tree XML-RPC server using SimpleXMLRPCServer.
"""

import sys
import SimpleXMLRPCServer
import logging
import xmlrpclib
import re
import threading
import commands
from ipalib import api
from ipalib import config
from ipaserver import conn
from ipaserver.servercore import context
from ipalib.util import xmlrpc_unmarshal
import traceback
import krbV

class StoppableXMLRPCServer(SimpleXMLRPCServer.SimpleXMLRPCServer):
    """Override of TIME_WAIT"""
    allow_reuse_address = True

    def serve_forever(self):
        self.stop = False
        while not self.stop:
          self.handle_request()

class LoggingSimpleXMLRPCRequestHandler(SimpleXMLRPCServer.SimpleXMLRPCRequestHandler):
    """Overides the default SimpleXMLRPCRequestHander to support logging.
       Logs client IP and the XML request and response.
    """

    def parse(self, given):
        """Convert the incoming arguments into the format IPA expects"""
        args = []
        kw = {}
        for g in given:
            kw[g] = unicode(given[g])
        return (args, kw)

    def _dispatch(self, method, params):
        """
        Dispatches the XML-RPC method.

        Methods beginning with an '_' are considered private and will
        not be called.
        """
        if method not in funcs:
            logger.error('no such method %r', method)
            raise Exception('method "%s" is not supported' % method)
        func = funcs[method]
        krbccache =  krbV.default_context().default_ccache().name
        context.conn = conn.IPAConn(
            api.env.ldap_host,
            api.env.ldap_port,
            krbccache,
        )
        logger.info('calling %s', method)
        (args, kw) = xmlrpc_unmarshal(*params)
        return func(*args, **kw)

    def _marshaled_dispatch(self, data, dispatch_method = None):
        try:
            params, method = xmlrpclib.loads(data)

            # generate response
            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:
            # report exception back to client. This is needed to report
            # tracebacks found in server code.
            e_class, e = sys.exc_info()[:2]
            # FIXME, need to get this number from somewhere...
            faultCode = getattr(e_class,'faultCode',1)
            tb_str = ''.join(traceback.format_exception(*sys.exc_info()))
            faultString = tb_str
            response = xmlrpclib.dumps(xmlrpclib.Fault(faultCode, faultString))

        return response

    def do_POST(self):
        clientIP, port = self.client_address
        # Log client IP and Port
        logger.info('Client IP: %s - Port: %s' % (clientIP, port))
        try:
            # get arguments
            data = self.rfile.read(int(self.headers["content-length"]))

            # unmarshal the XML data
            params, method = xmlrpclib.loads(data)
            logger.info('Call to %s(%s) from %s:%s', method,
                ', '.join(repr(p) for p in params),
                clientIP, port
            )

            # Log client request
            logger.debug('Client request: \n%s\n' % data)

            response = self._marshaled_dispatch(
                    data, getattr(self, '_dispatch', None))

            # Log server response
            logger.debug('Server response: \n%s\n' % response)
        except Exception, e:
            # This should only happen if the module is buggy
            # internal error, report as HTTP server error
            print e
            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)


if __name__ == '__main__':
    api.bootstrap_with_global_options(context='server')
    api.finalize()
    logger = api.log

    # Set up the server
    XMLRPCServer = StoppableXMLRPCServer(
        ('', api.env.lite_xmlrpc_port),
        LoggingSimpleXMLRPCRequestHandler
    )
    XMLRPCServer.register_introspection_functions()

    # Get and register all the methods

    for cmd in api.Command:
        logger.debug('registering %s', cmd)
        XMLRPCServer.register_function(api.Command[cmd], cmd)
    funcs = XMLRPCServer.funcs

    logger.info('Logging to file %r', api.env.log)
    logger.info('Listening on port %d', api.env.lite_xmlrpc_port)
    try:
        XMLRPCServer.serve_forever()
    except KeyboardInterrupt:
        XMLRPCServer.server_close()
        logger.info('Server shutdown.')