path: root/ZSI/dispatch.py

#! /usr/bin/env python
# $Header$
'''Simple CGI dispatching.
'''

import types, os, sys
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
from ZSI import *
from ZSI import _child_elements, _copyright, _seqtypes, _find_arraytype, _find_type, resolvers 
from ZSI.auth import _auth_tc, AUTH, ClientBinding


# Client binding information is stored in a global. We provide an accessor
# in case later on it's not.
_client_binding = None

def GetClientBinding():
    '''Return the client binding object.
    '''
    return _client_binding

gettypecode = lambda mod,e: getattr(mod, str(e.localName)).typecode
def _Dispatch(ps, modules, SendResponse, SendFault, nsdict={}, typesmodule=None, 
              gettypecode=gettypecode, rpc=False, docstyle=False, **kw):
    '''Find a handler for the SOAP request in ps; search modules.
    Call SendResponse or SendFault to send the reply back, appropriately.

    Behaviors:
        default -- Call "handler" method with pyobj representation of body root, and return
            a self-describing request (w/typecode).  Parsing done via a typecode from 
            typesmodule, or Any.

        docstyle -- Call "handler" method with ParsedSoap instance and parse result with an
          XML typecode (DOM). Behavior, wrap result in a body_root "Response" appended message.

        rpc -- Specify RPC wrapper of result. Behavior, ignore body root (RPC Wrapper)
           of request, parse all "parts" of message via individual typecodes.  Expect
           the handler to return the parts of the message, whether it is a dict, single instance, 
           or a list try to serialize it as a Struct but if this is not possible put it in an Array.
           Parsing done via a typecode from typesmodule, or Any.

    '''
    global _client_binding
    try:
        what = str(ps.body_root.localName)

        # See what modules have the element name.
        if modules is None:
            modules = ( sys.modules['__main__'], )

        handlers = [ getattr(m, what) for m in modules if hasattr(m, what) ]
        if len(handlers) == 0:
            raise TypeError("Unknown method " + what)

        # Of those modules, see who's callable.
        handlers = [ h for h in handlers if callable(h) ]
        if len(handlers) == 0:
            raise TypeError("Unimplemented method " + what)
        if len(handlers) > 1:
            raise TypeError("Multiple implementations found: " + `handlers`)
        handler = handlers[0]

        _client_binding = ClientBinding(ps)
        if docstyle:
            result = handler(ps.body_root)
            tc = TC.XML(aslist=1, pname=what+'Response')
        elif not rpc:
            try:
                tc = gettypecode(typesmodule, ps.body_root)
            except Exception:
                tc = TC.Any()

            try:
                arg = tc.parse(ps.body_root, ps)
            except EvaluateException, ex:
                SendFault(FaultFromZSIException(ex), **kw)
                return

            try:
                result = handler(arg)
            except Exception,ex:
                SendFault(FaultFromZSIException(ex), **kw)

            try:
                tc = result.typecode
            except AttributeError,ex:
                SendFault(FaultFromZSIException(ex), **kw)

        elif typesmodule is not None:
            kwargs = {}
            for e in _child_elements(ps.body_root):
                try:
                    tc = gettypecode(typesmodule, e)
                except Exception:
                    tc = TC.Any()

                try:
                    kwargs[str(e.localName)] = tc.parse(e, ps)
                except EvaluateException, ex:
                    SendFault(FaultFromZSIException(ex), **kw)
                    return

            result = handler(**kwargs)
            aslist = False
            # make sure data is wrapped, try to make this a Struct
            if type(result) in _seqtypes:
                 for o in result:
                     aslist = hasattr(result, 'typecode')
                     if aslist: break
            elif type(result) is not dict:
                 aslist = not hasattr(result, 'typecode')
                 result = (result,)

            tc = TC.Any(pname=what+'Response', aslist=aslist)
        else:
            # if this is an Array, call handler with list
            # if this is an Struct, call handler with dict
            tp = _find_type(ps.body_root)
            isarray = ((type(tp) in (tuple,list) and tp[1] == 'Array') or _find_arraytype(ps.body_root))
            data = _child_elements(ps.body_root)
            tc = TC.Any()
            if isarray and len(data) == 0:
                result = handler()
            elif isarray:
                try: arg = [ tc.parse(e, ps) for e in data ]
                except EvaluateException, e:
                    #SendFault(FaultFromZSIException(e), **kw)
                    SendFault(RuntimeError("THIS IS AN ARRAY: %s" %isarray))
                    return

                result = handler(*arg)
            else:
                try: kwarg = dict([ (str(e.localName),tc.parse(e, ps)) for e in data ])
                except EvaluateException, e:
                    SendFault(FaultFromZSIException(e), **kw)
                    return

                result = handler(**kwarg)

            # reponse typecode
            #tc = getattr(result, 'typecode', TC.Any(pname=what+'Response'))
            tc = TC.Any(pname=what+'Response')

        sw = SoapWriter(nsdict=nsdict)
        sw.serialize(result, tc)
        return SendResponse(str(sw), **kw)
    except Fault, e:
        return SendFault(e, **kw)
    except Exception, e:
        # Something went wrong, send a fault.
        return SendFault(FaultFromException(e, 0, sys.exc_info()[2]), **kw)


def _ModPythonSendXML(text, code=200, **kw):
    req = kw['request']
    req.content_type = 'text/xml'
    req.content_length = len(text)
    req.send_http_header()
    req.write(text)


def _ModPythonSendFault(f, **kw):
    _ModPythonSendXML(f.AsSOAP(), 500, **kw)

def _JonPySendFault(f, **kw):
    _JonPySendXML(f.AsSOAP(), 500, **kw)

def _JonPySendXML(text, code=200, **kw):
    req = kw['request']
    req.set_header("Content-Type", 'text/xml; charset="utf-8"')
    req.set_header("Content-Length", str(len(text)))
    req.write(text)

def _CGISendXML(text, code=200, **kw):
    print 'Status: %d' % code
    print 'Content-Type: text/xml; charset="utf-8"'
    print 'Content-Length: %d' % len(text)
    print ''
    print text

def _CGISendFault(f, **kw):
    _CGISendXML(f.AsSOAP(), 500, **kw)


class SOAPRequestHandler(BaseHTTPRequestHandler):
    '''SOAP handler.
    '''
    server_version = 'ZSI/1.1 ' + BaseHTTPRequestHandler.server_version

    def send_xml(self, text, code=200):
        '''Send some XML.
        '''
        self.send_response(code)
        
        if text:
            self.send_header('Content-type', 'text/xml; charset="utf-8"')
            self.send_header('Content-Length', str(len(text)))

        self.end_headers()
        
        if text:
            self.wfile.write(text)

        self.wfile.flush()

    def send_fault(self, f, code=500):
        '''Send a fault.
        '''
        self.send_xml(f.AsSOAP(), code)

    def do_POST(self):
        '''The POST command.
        '''
        try:
            ct = self.headers['content-type']
            if ct.startswith('multipart/'):
                cid = resolvers.MIMEResolver(ct, self.rfile)
                xml = cid.GetSOAPPart()
                ps = ParsedSoap(xml, resolver=cid.Resolve)
            else:
                length = int(self.headers['content-length'])
                ps = ParsedSoap(self.rfile.read(length))
        except ParseException, e:
            self.send_fault(FaultFromZSIException(e))
            return
        except Exception, e:
            # Faulted while processing; assume it's in the header.
            self.send_fault(FaultFromException(e, 1, sys.exc_info()[2]))
            return

        _Dispatch(ps, self.server.modules, self.send_xml, self.send_fault,
                  docstyle=self.server.docstyle, nsdict=self.server.nsdict,
                  typesmodule=self.server.typesmodule, rpc=self.server.rpc)

def AsServer(port=80, modules=None, docstyle=False, nsdict={}, typesmodule=None,
             rpc=False, addr=''):
    address = (addr, port)
    httpd = HTTPServer(address, SOAPRequestHandler)
    httpd.modules = modules
    httpd.docstyle = docstyle
    httpd.nsdict = nsdict
    httpd.typesmodule = typesmodule
    httpd.rpc = rpc
    httpd.serve_forever()

def AsCGI(nsdict={}, typesmodule=None, rpc=False, modules=None):
    '''Dispatch within a CGI script.
    '''
    if os.environ.get('REQUEST_METHOD') != 'POST':
        _CGISendFault(Fault(Fault.Client, 'Must use POST'))
        return
    ct = os.environ['CONTENT_TYPE']
    try:
        if ct.startswith('multipart/'):
            cid = resolvers.MIMEResolver(ct, sys.stdin)
            xml = cid.GetSOAPPart()
            ps = ParsedSoap(xml, resolver=cid.Resolve)
        else:
            length = int(os.environ['CONTENT_LENGTH'])
            ps = ParsedSoap(sys.stdin.read(length))
    except ParseException, e:
        _CGISendFault(FaultFromZSIException(e))
        return
    _Dispatch(ps, modules, _CGISendXML, _CGISendFault, nsdict=nsdict,
              typesmodule=typesmodule, rpc=rpc)

def AsHandler(request=None, modules=None, **kw):
    '''Dispatch from within ModPython.'''
    ps = ParsedSoap(request)
    kw['request'] = request
    _Dispatch(ps, modules, _ModPythonSendXML, _ModPythonSendFault, **kw)
    
def AsJonPy(request=None, modules=None, **kw):
    '''Dispatch within a jonpy CGI/FastCGI script.
    '''

    kw['request'] = request
    if request.environ.get('REQUEST_METHOD') != 'POST':
        _JonPySendFault(Fault(Fault.Client, 'Must use POST'), **kw)
        return
    ct = request.environ['CONTENT_TYPE']
    try:
        if ct.startswith('multipart/'):
            cid = resolvers.MIMEResolver(ct, request.stdin)
            xml = cid.GetSOAPPart()
            ps = ParsedSoap(xml, resolver=cid.Resolve)
        else:
            length = int(request.environ['CONTENT_LENGTH'])
            ps = ParsedSoap(request.stdin.read(length))
    except ParseException, e:
        _JonPySendFault(FaultFromZSIException(e), **kw)
        return
    _Dispatch(ps, modules, _JonPySendXML, _JonPySendFault, **kw)


if __name__ == '__main__': print _copyright