# This program is free software; you can redistribute it and/or modify
# it under the terms of the (LGPL) GNU Lesser General Public License as
# published by the Free Software Foundation; either version 3 of the 
# License, or (at your option) any later version.
#
# 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 Library Lesser General Public License for more details at
# ( http://www.gnu.org/licenses/lgpl.html ).
#
# You should have received a copy of the GNU Lesser 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.
# written by: Jeff Ortel ( jortel@redhat.com )

"""
The I{2nd generation} service proxy provides access to web services.
See I{README.txt}
"""

import suds
import suds.metrics as metrics
from cookielib import CookieJar
from suds import *
from suds.reader import DefinitionsReader
from suds.transport import TransportError, Request
from suds.transport.https import HttpAuthenticated
from suds.servicedefinition import ServiceDefinition
from suds import sudsobject
from sudsobject import Factory as InstFactory
from sudsobject import Object
from suds.resolver import PathResolver
from suds.builder import Builder
from suds.wsdl import Definitions
from suds.cache import ObjectCache
from suds.sax.document import Document
from suds.sax.parser import Parser
from suds.options import Options
from suds.properties import Unskin
from urlparse import urlparse
from copy import deepcopy
from logging import getLogger

log = getLogger(__name__)


class Client(object):
    """ 
    A lightweight web services client.
    I{(2nd generation)} API.
    @ivar wsdl: The WSDL object.
    @type wsdl:L{Definitions}
    @ivar service: The service proxy used to invoke operations.
    @type service: L{Service}
    @ivar factory: The factory used to create objects.
    @type factory: L{Factory}
    @ivar sd: The service definition
    @type sd: L{ServiceDefinition}
    @ivar messages: The last sent/received messages.
    @type messages: str[2]
    """
    @classmethod
    def items(cls, sobject):
        """
        Extract the I{items} from a suds object much like the
        items() method works on I{dict}.
        @param sobject: A suds object
        @type sobject: L{Object}
        @return: A list of items contained in I{sobject}.
        @rtype: [(key, value),...]
        """
        return sudsobject.items(sobject)
    
    @classmethod
    def dict(cls, sobject):
        """
        Convert a sudsobject into a dictionary.
        @param sobject: A suds object
        @type sobject: L{Object}
        @return: A python dictionary containing the
            items contained in I{sobject}.
        @rtype: dict
        """
        return sudsobject.asdict(sobject)
    
    @classmethod
    def metadata(cls, sobject):
        """
        Extract the metadata from a suds object.
        @param sobject: A suds object
        @type sobject: L{Object}
        @return: The object's metadata
        @rtype: L{sudsobject.Metadata}
        """
        return sobject.__metadata__

    def __init__(self, url, **kwargs):
        """
        @param url: The URL for the WSDL.
        @type url: str
        @param kwargs: keyword arguments.
        @see: L{Options}
        """
        options = Options()
        options.transport = HttpAuthenticated()
        self.options = options
        options.cache = ObjectCache(days=1)
        self.set_options(**kwargs)
        reader = DefinitionsReader(options, Definitions)
        self.wsdl = reader.open(url)
        self.factory = Factory(self.wsdl)
        self.service = ServiceSelector(self, self.wsdl.services)
        self.sd = []
        for s in self.wsdl.services:
            sd = ServiceDefinition(self.wsdl, s)
            self.sd.append(sd)
        self.messages = dict(tx=None, rx=None)
        
    def set_options(self, **kwargs):
        """
        Set options.
        @param kwargs: keyword arguments.
        @see: L{Options}
        """
        p = Unskin(self.options)
        p.update(kwargs)
        
    def add_prefix(self, prefix, uri):
        """
        Add I{static} mapping of an XML namespace prefix to a namespace.
        This is useful for cases when a wsdl and referenced schemas make heavy
        use of namespaces and those namespaces are subject to changed.
        @param prefix: An XML namespace prefix.
        @type prefix: str
        @param uri: An XML namespace URI.
        @type uri: str
        @raise Exception: when prefix is already mapped.
        """
        root = self.wsdl.root
        mapped = root.resolvePrefix(prefix, None)
        if mapped is None:
            root.addPrefix(prefix, uri)
            return
        if mapped[1] != uri:
            raise Exception('"%s" already mapped as "%s"' % (prefix, mapped))
        
    def last_sent(self):
        """
        Get last sent I{soap} message.
        @return: The last sent I{soap} message.
        @rtype: L{Document}
        """
        return self.messages.get('tx')
    
    def last_received(self):
        """
        Get last received I{soap} message.
        @return: The last received I{soap} message.
        @rtype: L{Document}
        """
        return self.messages.get('rx')
    
    def clone(self):
        """
        Get a shallow clone of this object.
        The clone only shares the WSDL.  All other attributes are
        unique to the cloned object including options.
        @return: A shallow clone.
        @rtype: L{Client}
        """
        class Uninitialized(Client):
            def __init__(self):
                pass
        clone = Uninitialized()
        clone.options = Options()
        cp = Unskin(clone.options)
        mp = Unskin(self.options)
        cp.update(deepcopy(mp))
        clone.wsdl = self.wsdl
        clone.factory = self.factory
        clone.service = ServiceSelector(clone, self.wsdl.services)
        clone.sd = self.sd
        clone.messages = dict(tx=None, rx=None)
        return clone
 
    def __str__(self):
        return unicode(self)
        
    def __unicode__(self):
        s = ['\n']
        build = suds.__build__.split()
        s.append('Suds ( https://fedorahosted.org/suds/ )')
        s.append('  version: %s' % suds.__version__)
        s.append(' %s  build: %s' % (build[0], build[1]))
        for sd in self.sd:
            s.append('\n\n%s' % unicode(sd))
        return ''.join(s)


class Factory:
    """
    A factory for instantiating types defined in the wsdl
    @ivar resolver: A schema type resolver.
    @type resolver: L{PathResolver}
    @ivar builder: A schema object builder.
    @type builder: L{Builder}
    """
    
    def __init__(self, wsdl):
        """
        @param wsdl: A schema object.
        @type wsdl: L{wsdl.Definitions}
        """
        self.wsdl = wsdl
        self.resolver = PathResolver(wsdl)
        self.builder = Builder(self.resolver)
    
    def create(self, name):
        """
        create a WSDL type by name
        @param name: The name of a type defined in the WSDL.
        @type name: str
        @return: The requested object.
        @rtype: L{Object}
        """
        timer = metrics.Timer()
        timer.start()
        type = self.resolver.find(name)
        if type is None:
            raise TypeNotFound(name)
        if type.enum():
            result = InstFactory.object(name)
            for e, a in type.children():
                setattr(result, e.name, e.name)
        else:
            try:
                result = self.builder.build(type)
            except Exception, e:
                log.error("create '%s' failed", name, exc_info=True)
                raise BuildError(name, e)
        timer.stop()
        metrics.log.debug('%s created: %s', name, timer)
        return result
    
    def separator(self, ps):
        """
        Set the path separator.
        @param ps: The new path separator.
        @type ps: char
        """
        self.resolver = PathResolver(self.wsdl, ps)


class ServiceSelector:
    """
    The B{service} selector is used to select a web service.
    In most cases, the wsdl only defines (1) service in which access
    by subscript is passed through to a L{PortSelector}.  This is also the
    behavior when a I{default} service has been specified.  In cases
    where multiple services have been defined and no default has been
    specified, the service is found by name (or index) and a L{PortSelector}
    for the service is returned.  In all cases, attribute access is
    forwarded to the L{PortSelector} for either the I{first} service or the
    I{default} service (when specified).
    @ivar __client: A suds client.
    @type __client: L{Client}
    @ivar __services: A list of I{wsdl} services.
    @type __services: list
    """
    def __init__(self, client, services):
        """
        @param client: A suds client.
        @type client: L{Client}
        @param services: A list of I{wsdl} services.
        @type services: list
        """
        self.__client = client
        self.__services = services
    
    def __getattr__(self, name):
        """
        Request to access an attribute is forwarded to the
        L{PortSelector} for either the I{first} service or the
        I{default} service (when specified).
        @param name: The name of a method.
        @type name: str
        @return: A L{PortSelector}.
        @rtype: L{PortSelector}. 
        """
        default = self.__ds()
        if default is None:
            port = self.__find(0)
        else:
            port = default
        return getattr(port, name)
    
    def __getitem__(self, name):
        """
        Provides selection of the I{service} by name (string) or 
        index (integer).  In cases where only (1) service is defined
        or a I{default} has been specified, the request is forwarded
        to the L{PortSelector}.
        @param name: The name (or index) of a service.
        @type name: (int|str)
        @return: A L{PortSelector} for the specified service.
        @rtype: L{PortSelector}. 
        """
        if len(self.__services) == 1:
            port = self.__find(0)
            return port[name]
        default = self.__ds()
        if default is not None:
            port = default
            return port[name]
        return self.__find(name)
    
    def __find(self, name):
        """
        Find a I{service} by name (string) or index (integer).
        @param name: The name (or index) of a service.
        @type name: (int|str)
        @return: A L{PortSelector} for the found service.
        @rtype: L{PortSelector}. 
        """
        service = None
        if not len(self.__services):
            raise Exception, 'No services defined'
        if isinstance(name, int):
            try:
                service = self.__services[name]
                name = service.name
            except IndexError:
                raise ServiceNotFound, 'at [%d]' % name
        else:
            for s in self.__services:
                if name == s.name:
                    service = s
                    break
        if service is None:
            raise ServiceNotFound, name
        return PortSelector(self.__client, service.ports, name)
    
    def __ds(self):
        """
        Get the I{default} service if defined in the I{options}.
        @return: A L{PortSelector} for the I{default} service.
        @rtype: L{PortSelector}. 
        """
        ds = self.__client.options.service
        if ds is None:
            return None
        else:
            return self.__find(ds)


class PortSelector:
    """
    The B{port} selector is used to select a I{web service} B{port}.
    In cases where multiple ports have been defined and no default has been
    specified, the port is found by name (or index) and a L{MethodSelector}
    for the port is returned.  In all cases, attribute access is
    forwarded to the L{MethodSelector} for either the I{first} port or the
    I{default} port (when specified).
    @ivar __client: A suds client.
    @type __client: L{Client}
    @ivar __ports: A list of I{service} ports.
    @type __ports: list
    @ivar __qn: The I{qualified} name of the port (used for logging).
    @type __qn: str
    """
    def __init__(self, client, ports, qn):
        """
        @param client: A suds client.
        @type client: L{Client}
        @param ports: A list of I{service} ports.
        @type ports: list
        @param qn: The name of the service.
        @type qn: str
        """
        self.__client = client
        self.__ports = ports
        self.__qn = qn
    
    def __getattr__(self, name):
        """
        Request to access an attribute is forwarded to the
        L{MethodSelector} for either the I{first} port or the
        I{default} port (when specified).
        @param name: The name of a method.
        @type name: str
        @return: A L{MethodSelector}.
        @rtype: L{MethodSelector}. 
        """
        default = self.__dp()
        if default is None:
            m = self.__find(0)
        else:
            m = default
        return getattr(m, name)
    
    def __getitem__(self, name):
        """
        Provides selection of the I{port} by name (string) or 
        index (integer).  In cases where only (1) port is defined
        or a I{default} has been specified, the request is forwarded
        to the L{MethodSelector}.
        @param name: The name (or index) of a port.
        @type name: (int|str)
        @return: A L{MethodSelector} for the specified port.
        @rtype: L{MethodSelector}. 
        """
        default = self.__dp()
        if default is None:
            return self.__find(name)
        else:
            return default
    
    def __find(self, name):
        """
        Find a I{port} by name (string) or index (integer).
        @param name: The name (or index) of a port.
        @type name: (int|str)
        @return: A L{MethodSelector} for the found port.
        @rtype: L{MethodSelector}. 
        """
        port = None
        if not len(self.__ports):
            raise Exception, 'No ports defined: %s' % self.__qn
        if isinstance(name, int):
            qn = '%s[%d]' % (self.__qn, name)
            try:
                port = self.__ports[name]
            except IndexError:
                raise PortNotFound, qn
        else:
            qn = '.'.join((self.__qn, name))
            for p in self.__ports:
                if name == p.name:
                    port = p
                    break
        if port is None:
            raise PortNotFound, qn
        qn = '.'.join((self.__qn, port.name))
        return MethodSelector(self.__client, port.methods, qn)
    
    def __dp(self):
        """
        Get the I{default} port if defined in the I{options}.
        @return: A L{MethodSelector} for the I{default} port.
        @rtype: L{MethodSelector}. 
        """
        dp = self.__client.options.port
        if dp is None:
            return None
        else:
            return self.__find(dp)
    

class MethodSelector:
    """
    The B{method} selector is used to select a B{method} by name.
    @ivar __client: A suds client.
    @type __client: L{Client}
    @ivar __methods: A dictionary of methods.
    @type __methods: dict
    @ivar __qn: The I{qualified} name of the method (used for logging).
    @type __qn: str
    """
    def __init__(self, client, methods, qn):
        """
        @param client: A suds client.
        @type client: L{Client}
        @param methods: A dictionary of methods.
        @type methods: dict
        @param qn: The I{qualified} name of the port.
        @type qn: str
        """
        self.__client = client
        self.__methods = methods
        self.__qn = qn
    
    def __getattr__(self, name):
        """
        Get a method by name and return it in an I{execution wrapper}.
        @param name: The name of a method.
        @type name: str
        @return: An I{execution wrapper} for the specified method name.
        @rtype: L{Method}
        """
        return self[name]
    
    def __getitem__(self, name):
        """
        Get a method by name and return it in an I{execution wrapper}.
        @param name: The name of a method.
        @type name: str
        @return: An I{execution wrapper} for the specified method name.
        @rtype: L{Method}
        """
        m = self.__methods.get(name)
        if m is None:
            qn = '.'.join((self.__qn, name))
            raise MethodNotFound, qn
        return Method(self.__client, m)


class Method:
    """
    The I{method} (namespace) object.
    @ivar client: A client object.
    @type client: L{Client}
    @ivar method: A I{wsdl} method.
    @type I{wsdl} Method.
    """

    def __init__(self, client, method):
        """
        @param client: A client object.
        @type client: L{Client}
        @param method: A I{raw} method.
        @type I{raw} Method.
        """
        self.client = client
        self.method = method
    
    def __call__(self, *args, **kwargs):
        """
        Invoke the method.
        """
        clientclass = self.clientclass(kwargs)
        client = clientclass(self.client, self.method)
        if not self.faults():
            try:
                return client.invoke(args, kwargs)
            except WebFault, e:
                return (500, e)
        else:
            return client.invoke(args, kwargs)
        
    def faults(self):
        """ get faults option """
        return self.client.options.faults
        
    def clientclass(self, kwargs):
        """ get soap client class """
        if SimClient.simulation(kwargs):
            return SimClient
        else:
            return SoapClient


class SoapClient:
    """
    A lightweight soap based web client B{**not intended for external use}
    @ivar service: The target method.
    @type service: L{Service}
    @ivar method: A target method.
    @type method: L{Method}
    @ivar options: A dictonary of options.
    @type options: dict
    @ivar cookiejar: A cookie jar.
    @type cookiejar: libcookie.CookieJar
    """

    def __init__(self, client, method):
        """
        @param client: A suds client.
        @type client: L{Client}
        @param method: A target method.
        @type method: L{Method}
        """
        self.client = client
        self.method = method
        self.options = client.options
        self.cookiejar = CookieJar()
        
    def invoke(self, args, kwargs):
        """
        Send the required soap message to invoke the specified method
        @param args: A list of args for the method invoked.
        @type args: list
        @param kwargs: Named (keyword) args for the method invoked.
        @type kwargs: dict
        @return: The result of the method invocation.
        @rtype: I{builtin}|I{subclass of} L{Object}
        """
        timer = metrics.Timer()
        timer.start()
        result = None
        binding = self.method.binding.input
        msg = binding.get_message(self.method, args, kwargs)
        timer.stop()
        metrics.log.debug(
                "message for '%s' created: %s",
                self.method.name, timer)
        timer.start()
        result = self.send(msg)
        timer.stop()
        metrics.log.debug(
                "method '%s' invoked: %s",
                self.method.name, timer)
        return result
    
    def send(self, msg):
        """
        Send soap message.
        @param msg: A soap message to send.
        @type msg: basestring
        @return: The reply to the sent message.
        @rtype: I{builtin} or I{subclass of} L{Object}
        """
        result = None
        location = self.location()
        binding = self.method.binding.input
        transport = self.options.transport
        retxml = self.options.retxml
        log.debug('sending to (%s)\nmessage:\n%s', location, msg)
        try:
            self.last_sent(Document(msg))
            request = Request(location, str(msg))
            request.headers = self.headers()
            reply = transport.send(request)
            if retxml:
                result = reply.message
            else:
                result = self.succeeded(binding, reply.message)
        except TransportError, e:
            if e.httpcode in (202,204):
                result = None
            else:
                log.error(self.last_sent())
                result = self.failed(binding, e)
        return result
    
    def headers(self):
        """
        Get http headers or the http/https request.
        @return: A dictionary of header/values.
        @rtype: dict
        """
        action = self.method.soap.action
        stock = { 'Content-Type' : 'text/xml', 'SOAPAction': action }
        result = dict(stock, **self.options.headers)
        log.debug('headers = %s', result)
        return result
    
    def succeeded(self, binding, reply):
        """
        Request succeeded, process the reply
        @param binding: The binding to be used to process the reply.
        @type binding: L{bindings.binding.Binding}
        @return: The method result.
        @rtype: I{builtin}, L{Object}
        @raise WebFault: On server.
        """
        log.debug('http succeeded:\n%s', reply)
        if len(reply) > 0:
            r, p = binding.get_reply(self.method, reply)
            self.last_received(r)
            if self.options.faults:
                return p
            else:
                return (200, p)
        else:
            if self.options.faults:
                return None
            else:
                return (200, None)
        
    def failed(self, binding, error):
        """
        Request failed, process reply based on reason
        @param binding: The binding to be used to process the reply.
        @type binding: L{suds.bindings.binding.Binding}
        @param error: The http error message
        @type error: L{transport.TransportError}
        """
        status, reason = (error.httpcode, tostr(error))
        reply = error.fp.read()
        log.debug('http failed:\n%s', reply)
        if status == 500:
            if len(reply) > 0:
                r, p = binding.get_fault(reply)
                self.last_received(r)
                return (status, p)
            else:
                return (status, None)
        if self.options.faults:
            raise Exception((status, reason))
        else:
            return (status, None)

    def location(self):
        p = Unskin(self.options)
        return p.get('location', self.method.location)
    
    def last_sent(self, d=None):
        key = 'tx'
        messages = self.client.messages
        if d is None:
            return messages.get(key)
        else:
            messages[key] = d
        
    def last_received(self, d=None):
        key = 'rx'
        messages = self.client.messages
        if d is None:
            return messages.get(key)
        else:
            messages[key] = d


class SimClient(SoapClient):
    """
    Loopback client used for message/reply simulation.
    """
    
    injkey = '__inject'
    
    @classmethod
    def simulation(cls, kwargs):
        """ get whether loopback has been specified in the I{kwargs}. """
        return kwargs.has_key(SimClient.injkey)
        
    def invoke(self, args, kwargs):
        """
        Send the required soap message to invoke the specified method
        @param args: A list of args for the method invoked.
        @type args: list
        @param kwargs: Named (keyword) args for the method invoked.
        @type kwargs: dict
        @return: The result of the method invocation.
        @rtype: I{builtin} or I{subclass of} L{Object}
        """
        simulation = kwargs[self.injkey]
        msg = simulation.get('msg')
        reply = simulation.get('reply')
        fault = simulation.get('fault')
        if msg is None:
            if reply is not None:
                return self.__reply(reply, args, kwargs)
            if fault is not None:
                return self.__fault(fault)
            raise Exception('(reply|fault) expected when msg=None')
        sax = Parser()
        msg = sax.parse(string=msg)
        return self.send(msg)
    
    def __reply(self, reply, args, kwargs):
        """ simulate the reply """
        binding = self.method.binding.input
        msg = binding.get_message(self.method, args, kwargs)
        log.debug('inject (simulated) send message:\n%s', msg)
        binding = self.method.binding.output
        return self.succeeded(binding, reply)
    
    def __fault(self, reply):
        """ simulate the (fault) reply """
        binding = self.method.binding.output
        if self.options.faults:
            r, p = binding.get_fault(reply)
            self.last_received(r)
            return (500, p)
        else:
            return (500, None)
