VmomiSupport.py

# VMware vSphere Python SDK
# Copyright (c) 2008-2013 VMware, Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

## VMOMI support code
from __future__ import with_statement # 2.5 only

from datetime import datetime
import Iso8601
import base64
import threading
NoneType = type(None)
try:
   from pyVmomiSettings import allowGetSet
   _allowGetSet = allowGetSet
except:
   _allowGetSet = True

try:
   from pyVmomiSettings import allowCapitalizedNames
   _allowCapitalizedNames = allowCapitalizedNames
except:
   _allowCapitalizedNames = True

(F_LINK,
 F_LINKABLE,
 F_OPTIONAL) = [ 1<<x for x in range(3) ]

BASE_VERSION = 'vmodl.version.version0'
VERSION1     = 'vmodl.version.version1'

XMLNS_XSD = "http://www.w3.org/2001/XMLSchema"
XMLNS_XSI = "http://www.w3.org/2001/XMLSchema-instance"
XMLNS_VMODL_BASE = "urn:vim25"

# The lock ensures that we serialize the lazy loading. In particular, we need
# to guard against multiple threads loading the same types on the same kind
# of objects at the same time
# The lock is protecting the following variables:
#  _topLevelNames, _*DefMap, and _dependencyMap
_lazyLock = threading.RLock()

# Also referenced in __init__.py
_topLevelNames = set()

# Maps to store parameters to create the type for each vmodlName
_managedDefMap = {}
_dataDefMap = {}
_enumDefMap = {}

# Map to store parameters to create the type for each wsdlName
_wsdlDefMap = {}

# Map that stores the nested classes for a given class
# if a.b.c and a.b.d are the nested classes of a.b, then _dependencyMap[a.b] = {c,d}
_dependencyMap = {}

## Update the dependency map
#  Note: Must be holding the _lazyLock
#
# @param names VmodlName of the type
def _AddToDependencyMap(names):
   """ Note: Must be holding the _lazyLock """
   curName = names[0]
   _topLevelNames.add(curName)
   for name in names[1:]:
      _dependencyMap.setdefault(curName, set()).add(name)
      curName = ".".join([curName, name])

## Check if a particular name is dependent on another
#  Note: Must be holding the _lazyLock
#
# @param parent Parent Vmodl name
# @param name Vmodl name to be checked for dependency
# @return True, if name depends on parent, False otherwise
def _CheckForDependency(parent, name):
   """ Note: Must be holding the _lazyLock """
   if _allowCapitalizedNames:
      # If the flag is set, check for both capitalized and
      # uncapitalized form. This is a temporary fix for handling
      # vim.EsxCLI namespace.
      # Ex: If we add vim.EsxCLI.vdisk, then
      # _dependencyMap['vim.EsxCLI'] will have value ['vdisk'].
      # When we try to check dependency for vdisk, since the flag
      # is set, we will uncapitalize EsxCLI and this will result
      # in attribute error
      dependents = _dependencyMap.get(parent)
      if not dependents:
         uncapitalizedParent = UncapitalizeVmodlName(parent)
         dependents = _dependencyMap.get(uncapitalizedParent)

      if dependents:
         if name in dependents or Uncapitalize(name) in dependents:
            return True
   else:
      dependents = _dependencyMap.get(parent)
      if dependents:
         if name in dependents:
            return True
   return False

## Checks for the type definition in all the maps
# and loads it if it finds the definition
#
# @param name vmodl name of the type
# @return vmodl type
def _LoadVmodlType(name):
   isArray = name.endswith("[]")
   if isArray:
      name = name[:-2]
   if _allowCapitalizedNames:
      name = UncapitalizeVmodlName(name)

   with _lazyLock:
      for defMap, loadFn in [(_dataDefMap, LoadDataType),
                            (_managedDefMap, LoadManagedType),
                            (_enumDefMap, LoadEnumType)]:
         dic = defMap.get(name)
         if dic:
            typ = loadFn(*dic)
            return isArray and typ.Array or typ

      return None

# In Python 2.4 and earlier, exceptions are old-style classes, so data objects
# must be old-style too.  For 2.5 and newer, data objects must be new-style
# classes
if issubclass(Exception, object):
   Base = object
   SetAttr = object.__setattr__
else:
   class Base: pass
   def SetAttr(obj, key, val):
      obj.__dict__[key] = val

## Simple class to store named attributes
class Object:
   ## Constructor
   def __init__(self, **kwargs):
      self.__dict__.update(kwargs)

# All properties and methods in vmodl types are created as LazyObject's
# in VmomiSupport. The attributes in these properties and methods that refer
# to vmodl types are "type", "result" and "methodResult". If a program tries
# to access any of these attributes, load the type. The vmodl name of the type
# can be retrieved by adding name to the attribute that is being accessed
# Creating a derived class of Object so that programs that want to use just
# Object are not affected
class LazyObject(Object):

   def __getattr__(self, attr):
      with _lazyLock:
         # Check if another thread already initialized this
         obj = self.__dict__.get(attr)
         if obj:
            return obj

         if attr == "type" or attr == "result" or attr == "methodResult":
            attrName = attr + "Name"
            vmodlName = getattr(self, attrName)
            vmodlType = GetVmodlType(vmodlName)
            setattr(self, attr, vmodlType)
            delattr(self, attrName)
            return vmodlType
         else:
            raise AttributeError(attr)

class Link(unicode):
   def __new__(cls, obj):
      if isinstance(obj, basestring):
         return unicode.__new__(cls, obj)
      elif isinstance(obj, DataObject):
         if obj.key:
            return unicode.__new__(cls, obj.key)
         raise AttributeError("DataObject does not have a key to link")
      else:
         raise ValueError

## LazyType to wrap around actual type
# This is used to intercept attribute accesses of a class
# and load the appropriate nested classes on-demand
class LazyType(type):

   def __getattr__(self, attr):
      if attr.endswith("[]"):
         searchName = attr[:-2]
      else:
         searchName = attr

      with _lazyLock:
         nestedClasses = _dependencyMap.get(self.__name__, [])
         if searchName in nestedClasses:
            return GetVmodlType(self.__name__ + "." +  attr)
         else:
            return super(LazyType, self).__getattribute__(attr)

## LazyModule class
# Used as a placeholder until the actual type is loaded
# If someone wants to use the type, then it is loaded on-demand
class LazyModule(object):

   def __init__(self, name):
      # name is used to save the current context of the object
      # If it is created because of reference to a.b, name will
      # be a.b
      self.name = name

   def __getattr__(self, attr):
      # If someone tries to introspect the instance of this class
      # using inspect.isclass(), the function will check if the object
      # has __bases__ attr. So, throwing an AttributeError to make it work
      if attr == "__bases__":
         raise AttributeError

      with _lazyLock:
         # Check if we have already loaded the class or object
         # corresponding to this attribute
         obj = self.__dict__.get(attr)
         if obj:
            return obj

         name = ".".join([self.name, attr])
         # Get the actual vmodlName from the type dictionaries
         actualName = _GetActualName(name)
         if actualName:
            typeObj = GetVmodlType(actualName)
         else:
            if _CheckForDependency(self.name, attr):
               typeObj = LazyModule(name)
            elif self.name == "vim":
               try:
                  typeObj = GetWsdlType(XMLNS_VMODL_BASE, attr)
               except:
                  raise AttributeError(attr)
            else:
               raise AttributeError(attr)
         setattr(self, attr, typeObj)
         return typeObj

   # If the lazy module is representing a data object,
   # this will get triggered when some code tries to initialize it
   # Load the actual type and pass the arguments to it's init.
   def __call__(self, **kwargs):
      typ = _LoadVmodlType(self.name)
      if typ:
         return typ.__call__(**kwargs)
      else:
         raise AttributeError("'%s' does not exist" % self.name)

## Format a python VMOMI object
#
# @param val the object
# @param info the field
# @param indent the level of indentation
# @return the formatted string
def FormatObject(val, info=Object(name="", type=object, flags=0), indent=0):
   start = indent * "   " + (info.name and "%s = " % info.name or "")
   if val == None:
      result = "<unset>"
   elif isinstance(val, DataObject):
      if info.flags & F_LINK:
         result = "<%s:%s>" % (val.__class__.__name__, val.key)
      else:
         result = "(%s) {\n%s\n%s}" % (val.__class__.__name__,
            ',\n'.join([FormatObject(getattr(val, prop.name), prop, indent+1)
                        for prop in val._GetPropertyList()]), indent * "   ")
   elif isinstance(val, ManagedObject):
      if val._serverGuid is None:
         result = "'%s:%s'" % (val.__class__.__name__, val._moId)
      else:
         result = "'%s:%s:%s'" % (val.__class__.__name__, val._serverGuid,
                                  val._moId)
   elif isinstance(val, list):
      itemType = getattr(val, 'Item', getattr(info.type, 'Item', object))
      if val:
         item = Object(name="", type=itemType, flags=info.flags)
         result = "(%s) [\n%s\n%s]" % (itemType.__name__,
            ',\n'.join([FormatObject(obj, item, indent+1) for obj in val]),
            indent * "   ")
      else:
         result = "(%s) []" % itemType.__name__
   elif isinstance(val, type):
      result = val.__name__
   elif isinstance(val, ManagedMethod):
      result = '%s.%s' % (val.info.type.__name__, val.info.name)
   elif isinstance(val, bool):
      result = val and "true" or "false"
   elif isinstance(val, datetime):
      result = Iso8601.ISO8601Format(val)
   elif isinstance(val, binary):
      result = base64.b64encode(val)
   else:
      result = repr(val)
   return start + result

## Lookup a property for a given object type
#
# @param type the type
# @param name the name of the property
def GetPropertyInfo(type, name):
   try:
      while name not in type._propInfo:
         type = type.__bases__[0]
      else:
         return type._propInfo[name]
   except Exception:
      raise AttributeError(name)

## VMOMI Managed Object class
class ManagedObject(object):
   _wsdlName = "ManagedObject"
   _propInfo = {}
   _propList = []
   _methodInfo = {}
   _version = BASE_VERSION

   ## Constructor
   #
   # @param[in] self self
   # @param[in] moId The ID of this managed object
   # @param[in] stub The stub adapter, if this is a client stub object
   def __init__(self, moId, stub=None, serverGuid=None):
      object.__setattr__(self, "_moId", moId)
      object.__setattr__(self, "_stub", stub)
      object.__setattr__(self, "_serverGuid", serverGuid)

   ## Invoke a managed method
   #
   # @param info method info
   # @param self self
   # @param ... arguments
   def _InvokeMethod(info, self, *posargs, **kwargs):
      if len(posargs) > len(info.params):
         s = "s"*(len(info.params)!=1)
         raise TypeError("%s() takes at most %d argument%s (%d given)" %
            (Capitalize(info.name),  len(info.params), s, len(posargs)))
      args = list(posargs) + [None] * (len(info.params) - len(posargs))
      if len(kwargs) > 0:
         paramNames = [param.name for param in info.params]
         for (k, v) in kwargs.items():
            try:
               idx = paramNames.index(k)
            except ValueError:
               raise TypeError("%s() got an unexpected keyword argument '%s'" %
                              (Capitalize(info.name),  k))
            if idx < len(posargs):
               raise TypeError("%s() got multiple values for keyword argument '%s'" %
                              (Capitalize(info.name),  k))
            args[idx] = v
      map(CheckField, info.params, args)
      return self._stub.InvokeMethod(self, info, args)
   _InvokeMethod = staticmethod(_InvokeMethod)

   ## Invoke a managed property accessor
   #
   # @param info property info
   # @param self self
   def _InvokeAccessor(info, self):
      return self._stub.InvokeAccessor(self, info)
   _InvokeAccessor = staticmethod(_InvokeAccessor)

   ## Get the ID of a managed object
   def _GetMoId(self):
      return self._moId

   ## Get the serverGuid of a managed object
   def _GetServerGuid(self):
      return self._serverGuid

   ## Get the stub of a managed object
   def _GetStub(self):
      return self._stub

   ## Get a list of all properties of this type and base types
   #
   # @param cls The managed object type
   def _GetPropertyList(cls, includeBaseClassProps=True):
      if not includeBaseClassProps:
         return cls._propList
      prop = {}
      result = []
      while cls != ManagedObject:
         # Iterate through props, add info for prop not found in derived class
         result = [info for info in cls._propList
                   if prop.setdefault(info.name, cls) == cls] + result
         cls = cls.__bases__[0]
      return result
   _GetPropertyList = classmethod(_GetPropertyList)

   ## Get a list of all methods of this type and base types
   #
   # @param cls The managed object type
   def _GetMethodList(cls):
      meth = {}
      result = []
      while cls != ManagedObject:
         # Iterate through methods, add info for method not found in derived class
         result = [info for info in cls._methodInfo.values()
                   if meth.setdefault(info.name, cls) == cls] + result
         cls = cls.__bases__[0]
      return result
   _GetMethodList = classmethod(_GetMethodList)

   ## Lookup a method for a given managed object type
   #
   # @param type the type
   # @param name the name of the property
   def _GetMethodInfo(type, name):
      while hasattr(type, "_methodInfo"):
         try:
            return type._methodInfo[name]
         except KeyError:
            type = type.__bases__[0]
      raise AttributeError(name)
   _GetMethodInfo = classmethod(_GetMethodInfo)

   def __setattr__(self,*args):
      if self._stub is not None:
         raise Exception("Managed object attributes are read-only")
      else:
         object.__setattr__(self,*args)
   __delattr__ = __setattr__

   if _allowGetSet == True:
      def __getattr__(self, name):
         if name.startswith("Get"):
            return lambda : getattr(self, name[3].lower() + name[4:])
         elif name.startswith("Set"):
            return lambda val: setattr(self, name[3].lower() + name[4:], val)
         raise AttributeError(name)

   ## The equality test of ManagedObject is for client side only and might
   #  not be appropriate for server side objects. The server side object has
   #  to override this function if it has a different equality logic
   def __eq__(self, other):
      if other is None:
         return False
      else:
         return self._moId == other._moId and \
                self.__class__ == other.__class__ and \
                self._serverGuid == other._serverGuid

   def __hash__(self):
      return str(self).__hash__()

   __str__ = __repr__ = FormatObject
   _GetPropertyInfo = classmethod(GetPropertyInfo)

## VMOMI Data Object class
class DataObject(Base):
   _wsdlName = "DataObject"
   _propInfo = {}
   _propList = []
   _version = BASE_VERSION

   ## Constructor
   #
   # @param info property info
   # @param ... keyword arguments indicate properties
   def __init__(self, **kwargs):
      for info in self._GetPropertyList():
         if issubclass(info.type, list):
            SetAttr(self, info.name, info.type())
         elif info.flags & F_OPTIONAL:
            SetAttr(self, info.name, None)
         elif info.type is bool:
            SetAttr(self, info.name, False)
         elif issubclass(info.type, Enum):
            SetAttr(self, info.name, None)
         elif issubclass(info.type, str):
            SetAttr(self, info.name, "")
         elif info.type is long or \
            issubclass(info.type, int) or \
            issubclass(info.type, float):
            # Take care of byte, short, int, long, float and double
            SetAttr(self, info.name, info.type(0))
         else:
            SetAttr(self, info.name, None)
      for (k, v) in kwargs.items():
         setattr(self, k, v)

   ## Get a list of all properties of this type and base types
   #
   # @param cls the data object type
   def _GetPropertyList(cls, includeBaseClassProps=True):
      if not includeBaseClassProps:
         return cls._propList
      prop = {}
      result = []
      while cls != DataObject:
         # Iterate through props, add info for prop not found in derived class
         result = [info for info in cls._propList
                   if prop.setdefault(info.name, cls) == cls] + result
         cls = cls.__bases__[0]
      return result
   _GetPropertyList = classmethod(_GetPropertyList)

   def __setattr__(self, name, val):
      CheckField(self._GetPropertyInfo(name), val)
      SetAttr(self, name, val)

   if _allowGetSet == True:
      def __getattr__(self, name):
         if name.startswith("Get"):
            return lambda : getattr(self, name[3].lower() + name[4:])
         elif name.startswith("Set"):
            return lambda val: setattr(self, name[3].lower() + name[4:], val)
         raise AttributeError(name)

   _GetPropertyInfo = classmethod(GetPropertyInfo)
   __str__ = __repr__ = FormatObject

## Base class for enum types
class Enum(str): pass

## Base class for array types
class Array(list):
   __str__ = __repr__ = FormatObject

## Class for curried function objects
#
# Instances of this class are curried python function objects.
# If g = Curry(f, a1,...,an), then g(b1,...,bm) = f(a1,...,an, b1,...,bm)
class Curry(object):
   ## Constructor
   #
   # @param self self
   # @param f the function object
   # @param args arguments to fix
   def __init__(self, f, *args):
      self.f = f
      self.args = args

   def __call__(self, *args, **kwargs):
      args = self.args + args
      return self.f(*args, **kwargs)

   def __get__(self, obj, type):
      if obj:
         # curried methods will receive 'self' *after* any fixed arguments
         return lambda *args, **kwargs: \
                           self.f(*(self.args + (obj,) + args), **kwargs)
      return self

## Class for managed object methods
class ManagedMethod(Curry):
   ## Constructor
   #
   # @param self self
   # @param info method info
   def __init__(self, info):
      Curry.__init__(self, ManagedObject._InvokeMethod, info)
      self.info = info

## Create the vmodl.MethodFault type
#
# This type must be generated dynamically because it inherits from
# vmodl.DynamicData, which is created dynamically by the emitted code.
#
# @return the new type
def CreateAndLoadMethodFaultType():
   with _lazyLock:
      props = [["msg", "string", BASE_VERSION, F_OPTIONAL],
               ["faultCause", "vmodl.MethodFault", "vmodl.version.version1", F_OPTIONAL],
               ["faultMessage", "vmodl.LocalizableMessage[]", "vmodl.version.version1", F_OPTIONAL]]
      propInfo = {}
      propList = [ LazyObject(name=p[0], typeName=p[1], version=p[2], flags=p[3])
                   for p in props ]
      dic = {"_wsdlName" : "MethodFault", "_propInfo" : propInfo,
             "_propList" : propList, "_version" : BASE_VERSION}
      for info in propList:
         propInfo[info.name] = info
      name = "vmodl.MethodFault"
      CreateDataType("vmodl.MethodFault", "MethodFault", "vmodl.DynamicData", BASE_VERSION, props)
      return _AddType(type(Exception)(name,
                      (GetWsdlType(XMLNS_VMODL_BASE, "DynamicData"), Exception),
                      dic))

# If the name of nested class of vmodl type is same as one of the nested classes
# of its parent, then we have to replace it. Else it won't be possible to intercept
# it with LazyType class
# @param vmodl type
# @param parent of the vmodl type
# @return vmodl type
def _CheckNestedClasses(typ, parent):
   with _lazyLock:
      vmodlName = typ.__name__
      nestedClasses = _dependencyMap.get(vmodlName, [])
      for nestedClass in nestedClasses:
         if hasattr(parent, nestedClass):
            setattr(typ, nestedClass, GetVmodlType(vmodlName + "." + nestedClass))
      return typ

## Create and Load a data object type at once
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
# @return vmodl type
def CreateAndLoadDataType(vmodlName, wsdlName, parent, version, props):
   CreateDataType(vmodlName, wsdlName, parent, version, props)
   return LoadDataType(vmodlName, wsdlName, parent, version, props)

## Create a data object type
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
def CreateDataType(vmodlName, wsdlName, parent, version, props):
   with _lazyLock:
      dic = [vmodlName, wsdlName, parent, version, props]
      names = vmodlName.split(".")
      if _allowCapitalizedNames:
         vmodlName = ".".join(name[0].lower() + name[1:] for name in names)
      _AddToDependencyMap(names)
      typeNs = GetWsdlNamespace(version)

      _dataDefMap[vmodlName] = dic
      _wsdlDefMap[(typeNs, wsdlName)] = dic
      _wsdlTypeMapNSs.add(typeNs)

## Load a data object type
# This function also loads the parent of the type if it's not loaded yet
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
# @return the new data object type
def LoadDataType(vmodlName, wsdlName, parent, version, props):
   with _lazyLock:
      # Empty lists are saved as None in globals maps as it is much more memory
      # efficient. PythonStubEmitter files emit empty lists as None.
      if props is None:
         props = []
      propInfo = {}
      propList = []
      for p in props:
         # DataObject Property does not contain the privilege for emitted types.
         # However, DynamicTypeConstructor from DynamicTypeManagerHelper.py creates
         # DataTypes with properties containing privilege id.
         name, typeName, propVersion, flags = p[:4]
         if flags & F_LINK:
            if typeName.endswith("[]"):
               linkType = "Link[]"
            else:
               linkType = "Link"
            obj = LazyObject(name=name, typeName=linkType, version=propVersion,
                             flags=flags, expectedType=typeName)
         else:
            obj = LazyObject(name=name, typeName=typeName, version=propVersion,
                             flags=flags)
         propList.append(obj)
      dic = {"_wsdlName" : wsdlName, "_propInfo" : propInfo,
             "_propList" : propList, "_version" : version}
      for info in propList:
         propInfo[info.name] = info
      name = vmodlName
      parent = GetVmodlType(parent)
      result = _AddType(LazyType(name, (parent,), dic))

      # MethodFault and RuntimeFault are builtin types, but MethodFault extends
      # DynamicData, which is (erroneously?) an emitted type, so we can't create
      # MethodFault and RuntimeFault until we have loaded DynamicData
      if wsdlName == "DynamicData":
         CreateAndLoadMethodFaultType()
         CreateAndLoadDataType("vmodl.RuntimeFault", "RuntimeFault",
                        "vmodl.MethodFault", BASE_VERSION, [])
         # Strictly speaking LocalizedMethodFault is not a data object type
         # (it can't be used in VMODL) But it can be treated as a data object for
         # (de)serialization purpose
         CreateAndLoadDataType("vmodl.LocalizedMethodFault", "LocalizedMethodFault",
                        "vmodl.MethodFault", BASE_VERSION,
                        [("fault", "vmodl.MethodFault", BASE_VERSION, 0),
                         ("localizedMessage", "string", BASE_VERSION, F_OPTIONAL),
                        ])

      return _CheckNestedClasses(result, parent)

## Create and Load a managed object type at once
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
# @param methods methods of the type
# @return vmodl type
def CreateAndLoadManagedType(vmodlName, wsdlName, parent, version, props, methods):
   CreateManagedType(vmodlName, wsdlName, parent, version, props, methods)
   return LoadManagedType(vmodlName, wsdlName, parent, version, props, methods)

## Create a managed object type
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
# @param methods methods of the type
def CreateManagedType(vmodlName, wsdlName, parent, version, props, methods):
   with _lazyLock:
      dic = [vmodlName, wsdlName, parent, version, props, methods]
      names = vmodlName.split(".")
      if _allowCapitalizedNames:
         vmodlName = ".".join(name[0].lower() + name[1:] for name in names)

      _AddToDependencyMap(names)
      typeNs = GetWsdlNamespace(version)

      if methods:
         for meth in methods:
            _SetWsdlMethod(typeNs, meth[1], dic)

      _managedDefMap[vmodlName] = dic
      _wsdlDefMap[(typeNs, wsdlName)] = dic
      _wsdlTypeMapNSs.add(typeNs)

## Load a managed object type
# This function also loads the parent of the type if it's not loaded yet
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param parent the VMODL name of the parent type
# @param version the version of the type
# @param props properties of the type
# @param methods methods of the type
# @return the new managed object type
def LoadManagedType(vmodlName, wsdlName, parent, version, props, methods):
   with _lazyLock:
      # Empty lists are saved as None in globals maps as it is much more memory
      # efficient. PythonStubEmitter files emit empty lists as None.
      if props is None:
         props = []
      if methods is None:
         methods = []
      parent = GetVmodlType(parent)
      propInfo = {}
      methodInfo = {}
      propList = [LazyObject(name=p[0], typeName=p[1], version=p[2], flags=p[3],
                  privId=p[4]) for p in props]
      dic = {"_wsdlName" : wsdlName, "_propInfo" : propInfo,
             "_propList" : propList,
             "_methodInfo" : methodInfo, "_version" : version}
      for info in propList:
         propInfo[info.name] = info
         getter = Curry(ManagedObject._InvokeAccessor, info)
         dic[info.name] = property(getter)
      for (mVmodl, mWsdl, mVersion, mParams, mResult, mPrivilege, mFaults) in methods:
         if mFaults is None:
            mFaults = []
         mName = Capitalize(mVmodl)
         isTask = False
         if mName.endswith("_Task"):
            mName = mName[:-5]
            isTask = True
         params = tuple([LazyObject(name=p[0], typeName=p[1], version=p[2], flags=p[3],
                        privId=p[4]) for p in mParams])
         info = LazyObject(name=mName, typeName=vmodlName, wsdlName=mWsdl,
                       version=mVersion, params=params, isTask=isTask,
                       resultFlags=mResult[0], resultName=mResult[1],
                       methodResultName=mResult[2], privId=mPrivilege, faults=mFaults)
         methodInfo[mName] = info
         mm = ManagedMethod(info)
         ns = GetWsdlNamespace(info.version)
         method = _SetWsdlMethod(ns, info.wsdlName, mm)
         if method != mm:
            raise RuntimeError(
               "Duplicate wsdl method %s %s (new class %s vs existing %s)" % \
               (ns, info.wsdlName, mm.info.type, method.info.type))
         dic[mWsdl] = mm
         dic[mName] = mm
      name = vmodlName
      result = _AddType(LazyType(name, (parent,) , dic))

      return _CheckNestedClasses(result, parent)

## Create an enum type
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param version the version of the type
# @param values enum values
# @return vmodl type
def CreateAndLoadEnumType(vmodlName, wsdlName, version, values):
   CreateEnumType(vmodlName, wsdlName, version, values)
   return LoadEnumType(vmodlName, wsdlName, version, values)

## Create an enum type
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param version the version of the type
# @param values enum values
def CreateEnumType(vmodlName, wsdlName, version, values):
   with _lazyLock:
      dic = [vmodlName, wsdlName, version, values]
      names = vmodlName.split(".")
      if _allowCapitalizedNames:
         vmodlName = ".".join(name[0].lower() + name[1:] for name in names)

      _AddToDependencyMap(names)
      typeNs = GetWsdlNamespace(version)

      _enumDefMap[vmodlName] = dic
      _wsdlDefMap[(typeNs, wsdlName)] = dic
      _wsdlTypeMapNSs.add(typeNs)

## Load an enum type
#
# @param vmodlName the VMODL name of the type
# @param wsdlName the WSDL name of the type
# @param version the version of the type
# @param values enum values
# @return the new enum type
def LoadEnumType(vmodlName, wsdlName, version, values):
   with _lazyLock:
      name = vmodlName
      # Enum type cannot have nested classes. So, creating normal type
      # instead of LazyType
      result = type(name, (Enum,),
         {"_wsdlName" : wsdlName, "_version" : version})
      result.values = map(result, values)
      for value in result.values:
         setattr(result, value, value)
      return _AddType(result)

## Create an array type
#
# @param itemType the item type
# @return the new array type
def CreateArrayType(itemType):
   return type("%s[]" % itemType.__name__, (Array,), {'Item' : itemType})

## Add a new type to the type maps, create array constructors
#  Note: Must be holding the _lazyLock, or in main init path
#
# @param type the type object
# @return type
def _AddType(type):
   """ Note: Must be holding the _lazyLock, or in main init path """
   type.Array = CreateArrayType(type)

   typeNS = GetWsdlNamespace(type._version)
   newType = _SetWsdlType(typeNS, type._wsdlName, type)
   if newType != type:
      raise RuntimeError("Duplicate wsdl type %s (already in typemap)" % (type._wsdlName))

   return type

## Check that a value matches a given type, and annotate if neccesary
#
# @param info object containing of expected type
# @param val object to check
# @throw TypeError if the value does not match the type
def CheckField(info, val):
   with _lazyLock:
      valType = Type(val)
      if val is None or (isinstance(val, list) and len(val) == 0):
         # If type of the property is an Any. We should allow this to have
         # unset items
         if not (info.flags & F_OPTIONAL) and info.type is not object:
            raise TypeError('Required field "%s" not provided (not @optional)' % info.name)
         return
      elif info.type is object:
         try:
            GetQualifiedWsdlName(valType)
            return
         except KeyError:
            raise TypeError('Unknown type for %s' % info.type.__name__)
      elif isinstance(val, info.type):
         return
      elif issubclass(info.type, list):
         # Checking the values of VMOMI array types is surprisingly complicated....
         if isinstance(val, Array):
            # 1. We've got a PyVmomi Array object, which is effectively a typed list;
            # verify that the type of the Array is a subclass of the expected type.
            if issubclass(valType.Item, info.type.Item):
               return
            elif info.flags & F_LINK:
               # Allow objects of expected type to be assigned to links
               if issubclass(valType, GetVmodlType(info.expectedType)):
                  return
         elif val:
            # 2. We've got a non-empty Python list object, which is untyped;
            # walk the list and make sure that each element is a subclass
            # of the expected type.

            # Masking out F_OPTIONAL part of flags since we are checking for
            # each element of the list
            flags = info.flags & (F_LINKABLE | F_LINK)
            if flags & F_LINK:
               if info.expectedType.endswith('[]'):
                  expectedType = info.expectedType[:-2]
               else:
                  expectedType = info.expectedType
               itemInfo = Object(type=info.type.Item, name=info.name, flags=flags,
                                 expectedType=expectedType)
            else:
               itemInfo = Object(type=info.type.Item, name=info.name, flags=flags)
            for it in val:
               CheckField(itemInfo, it)
            return
         else:
            # 3. We've got None or an empty Python list object;
            # no checking required, since the result will be an empty array.
            return
      elif info.type is type and valType is type(Exception) \
        or issubclass(info.type, int) and issubclass(valType, int) \
        or issubclass(info.type, long) and (issubclass(valType, int) or \
                                            issubclass(valType, long)) \
        or issubclass(info.type, float) and issubclass(valType, float) \
        or issubclass(info.type, basestring) and issubclass(valType, basestring):
         return
      elif issubclass(info.type, Link):
         # Allow object of expected type to be assigned to link
         if issubclass(valType, GetVmodlType(info.expectedType)):
            return
      raise TypeError('For "%s" expected type %s, but got %s'
                    % (info.name, info.type.__name__, valType.__name__))

## Finalize a created type
#
# @param type a created type
def FinalizeType(type):
   if issubclass(type, DataObject):
      for info in type._propList:
         info.type = GetVmodlType(info.type)
   elif issubclass(type, ManagedObject):
      for info in type._propInfo.values():
         info.type = GetVmodlType(info.type)
      for info in type._methodInfo.values():
         info.result = GetVmodlType(info.result)
         info.methodResult = GetVmodlType(info.methodResult)
         info.type = GetVmodlType(info.type)
         for param in info.params:
            param.type = GetVmodlType(param.type)

## Get the type of an object, for both new and old-style classes
def Type(obj):
   try:
      return obj.__class__
   except AttributeError:
      return type(obj)

## Set a WSDL type with wsdl namespace and wsdl name
#  Internal to VmomiSupport
#
#  Note: Must be holding the _lazyLock, or in main init path
def _SetWsdlType(ns, wsdlName, typ):
   """
   Set a WSDL type with wsdl namespace and wsdl name.
   Returns added type / existing type if (ns, wsdlName) already in the map

   Note: Must be holding the _lazyLock, or in main init path
   """
   return _wsdlTypeMap.setdefault((ns, wsdlName), typ)

## Lookup a WSDL type from wsdl namespace and wsdl name
# @param ns XML namespace
# @param name wsdl name
# @return type if found else throws KeyError
def GetWsdlType(ns, name):
   if ns is None or name is None:
      raise KeyError("%s %s" % (ns, name))

   with _lazyLock:
      # Check if the type is loaded in the map
      typ = _wsdlTypeMap.get( (ns, name) )
      if typ:
         return typ
      # It is an array type, get the actual type and return the array
      elif name.startswith("ArrayOf"):
         try:
            return GetWsdlType(ns, name[7:]).Array
         except KeyError:
            raise KeyError("%s %s" % (ns, name))
      else:
         # Type is not loaded yet, load it
         typ = _LoadVmodlType(_wsdlDefMap[(ns, name)][0])
         if typ:
            return typ

      raise KeyError("%s %s" % (ns, name))

## Guess the type from wsdlname with no ns
#  WARNING! This should not be used in general, as there is no guarantee for
#  the correctness of the guessing type
# @param name wsdl name
# @return type if found in any one of the name spaces else throws KeyError
def GuessWsdlType(name):
   with _lazyLock:
      # Because the types are lazily loaded, if some name is present
      # in multiple namespaces, we will load the first type that we
      # encounter and return it.
      for ns in _wsdlTypeMapNSs:
         try:
            return GetWsdlType(ns, name)
         except KeyError:
            pass
      raise KeyError(name)

## Return a map that contains all the wsdl types
# This function is rarely used
# By calling GetWsdlType on all wsdl names, we will
# make sure that the types are loaded before returning
# the iterator
# @return iterator to the wsdl type map
def GetWsdlTypes():
   with _lazyLock:
      for ns, name in _wsdlDefMap:
         GetWsdlType(ns, name)
      return _wsdlTypeMap.itervalues()

## Get the qualified XML schema name (ns, name) of a type
def GetQualifiedWsdlName(type):
   with _lazyLock:
      wsdlNSAndName = _wsdlNameMap.get(type)
      if wsdlNSAndName:
         return wsdlNSAndName
      else:
         if issubclass(type, list):
            ns = GetWsdlNamespace(type.Item._version)
            return (ns, "ArrayOf" + Capitalize(type.Item._wsdlName))
         else:
            ns = GetWsdlNamespace(type._version)
            return (ns, type._wsdlName)

## Get the WSDL of a type
def GetWsdlName(type):
   return GetQualifiedWsdlName(type)[-1]

## Capitalize a string
def Capitalize(str):
   if str:
      return str[0].upper() + str[1:]
   return str

## Uncapitalize a string
def Uncapitalize(str):
   if str:
      return str[0].lower() + str[1:]
   return str

## To uncapitalize the entire vmodl name
# pyVmomi used to map Java package names to capitalized Python module names,
# but now maps the Java package names unchanged to Python module names.
# This function is needed to support the legacy name mapping.
def UncapitalizeVmodlName(str):
   if str:
      return ".".join(name[0].lower() + name[1:] for name in str.split("."))
   return str

## Add a parent version
def AddVersionParent(version, parent):
   parentMap[version][parent] = True

## Get version namespace from version
def GetVersionNamespace(version):
   """ Get version namespace from version """
   ns = nsMap[version]
   if not ns:
      ns = serviceNsMap[version]
   versionId = versionIdMap[version]
   if not versionId:
      namespace = ns
   else:
      namespace = '%s/%s' % (ns, versionId)
   return namespace

## Get version from the version uri
def GetVersionFromVersionUri(version):
   return versionMap[version.rsplit(":", 1)[-1]]

## Get wsdl namespace from version
def GetWsdlNamespace(version):
   """ Get wsdl namespace from version """
   return "urn:" + serviceNsMap[version]

## Get all the versions for the service with specified namespace (partially) ordered
## by compatibility (i.e. any version in the list that is compatible with some version
## v in the list will preceed v)
# @param namespace XML namespace identifying a service
# @return returns all the versions for the service with specified namespace (partially)
# ordered by compatibility
#
# NOTE: For this function, we use 'namespace' as a representation of 'service'.  While
#       this works for most services, for compatibility reasons, the core and query
#       services share the 'vim25' namespace with the vim service.  Fortunately, this
#       shouldn't be an issue in practice, as the implementations of the vim
#       service (vpxd and hostd) don't currently advertise that they support any
#       versions of the core or query services, and we don't expect that they ever will.
#       This function assumes that all other namespaces identify a unique service.
def GetServiceVersions(namespace):
   """
   Get all the versions for the service with specified namespace (partially) ordered
   by compatibility (i.e. any version in the list that is compatible with some version
   v in the list will preceed v)
   """
   versions = dict((v, True) for (v, n) in serviceNsMap.iteritems() if n == namespace)
   mappings = {}
   for v in versions.iterkeys():
      mappings[v] = set(parent for parent in parentMap[v].iterkeys()
                        if parent != v and versions.has_key(parent))
   res = []
   while True:
      el = [ k for (k, v) in mappings.iteritems() if len(v) == 0 ]
      if len(el) == 0:
         return res
      el.sort()
      for k in el:
         res.insert(0, k)
         del mappings[k]
         for values in mappings.itervalues():
            values.discard(k)


## Set a WSDL method with wsdl namespace and wsdl name
#  Internal to VmomiSupport
#  Note: Must be holding the _lazyLock
#
# @param ns XML namespace
# @param wsdlName wsdl name
# @param inputMM managed method object or info to load it (it points to
# list object that points to the type info which holds
# this managed method's information)
# @return returns added method or exising method if (ns, wsdlName)
# is already in the map. It throws a runtime error if
# trying to set two type info list's to the same (ns, wsdlName)
def _SetWsdlMethod(ns, wsdlName, inputMM):
   """
   Set a WSDL method with wsdl namespace and wsdl name
   Returns added method / existing method if (ns, wsdlName) already in the map

   Note: Must be holding the _lazyLock
   """
   _wsdlMethodNSs.add(ns)
   curMM = _wsdlMethodMap.get( (ns, wsdlName) )
   # if inputMM is a list
   if isinstance(inputMM, list):
      if curMM is None:
         _wsdlMethodMap[(ns, wsdlName)] = inputMM
         return inputMM
      elif isinstance(curMM, list):
         raise RuntimeError(
                   "Duplicate wsdl method %s %s (new class %s vs existing %s)" % \
                   (ns, wsdlName, inputMM[0], curMM[0]))
      else:
         return curMM
   # if inputMM is a ManagedMethod
   else:
      if curMM is None or isinstance(curMM, list):
         _wsdlMethodMap[(ns, wsdlName)] = inputMM
         return inputMM
      else:
         return curMM

## Get wsdl method from ns, wsdlName
# @param ns XML namespace
# @param wsdlName wsdl name
# @return managed method object or throws a KeyError
def GetWsdlMethod(ns, wsdlName):
   """ Get wsdl method from ns, wsdlName """
   with _lazyLock:
      method = _wsdlMethodMap[(ns, wsdlName)]
      if isinstance(method, ManagedMethod):
         # The type corresponding to the method is loaded,
         # just return the method object
         return method
      elif method:
         # The type is not loaded, the map contains the info
         # to load the type. Load the actual type and
         # return the method object
         LoadManagedType(*method)
         return _wsdlMethodMap[(ns, wsdlName)]
      else:
         raise KeyError("%s %s" % (ns, name))

## Guess the method from wsdlname with no ns
#  WARNING! This should not be used in general, as there is no guarantee for
#  the correctness of the guessing method
# @param name wsdl name
# @return managed method object if found in any namespace else throws
# KeyError
def GuessWsdlMethod(name):
   with _lazyLock:
      for ns in _wsdlMethodNSs:
         try:
            return GetWsdlMethod(ns, name)
         except KeyError:
            pass
      raise KeyError(name)

## Widen a type to one supported in a given version
def GetCompatibleType(type, version):
   # Type can be widened if it has the attribute "_version" (which implies it
   # is either a DataObject or ManagedObject)
   if hasattr(type, "_version"):
      while not IsChildVersion(version, type._version):
         type = type.__bases__[0]
   return type

## Invert an injective mapping
def InverseMap(map):
   return dict([ (v, k) for (k, v) in map.iteritems() ])

types = Object()
nsMap = {}
versionIdMap = {}
versionMap = {}
serviceNsMap = { BASE_VERSION : XMLNS_VMODL_BASE.split(":")[-1] }
parentMap = {}

from Version import AddVersion, IsChildVersion

if not isinstance(bool, type): # bool not a type in python <= 2.2
   bool = type("bool", (int,),
               {"__new__": lambda cls, val=0: int.__new__(cls, val and 1 or 0)})
byte  = type("byte", (int,), {})
short  = type("short", (int,), {})
double = type("double", (float,), {})
URI = type("URI", (str,), {})
binary = type("binary", (str,), {})
PropertyPath = type("PropertyPath", (unicode,), {})

# _wsdlTypeMapNSs store namespaces added to _wsdlTypeMap in _SetWsdlType
_wsdlTypeMapNSs = set()
_wsdlTypeMap = {
   # Note: xsd has no void type. This is a hack from before. Can be removed?
   (XMLNS_XSD, 'void') : NoneType,
   (XMLNS_XSD, 'anyType') : object,
   (XMLNS_XSD, 'boolean') : bool,
   (XMLNS_XSD, 'byte') : byte,
   (XMLNS_XSD, 'short') : short,
   (XMLNS_XSD, 'int') : int,
   (XMLNS_XSD, 'long') : long,
   (XMLNS_XSD, 'float') : float,
   (XMLNS_XSD, 'double') : double,
   (XMLNS_XSD, 'string') : str,
   (XMLNS_XSD, 'anyURI') : URI,
   (XMLNS_XSD, 'base64Binary') : binary,
   (XMLNS_XSD, 'dateTime') : datetime,
   (XMLNS_XSD, 'Link') : Link,
   (XMLNS_VMODL_BASE, 'TypeName') : type,
   (XMLNS_VMODL_BASE, 'MethodName') : ManagedMethod,
   (XMLNS_VMODL_BASE, 'PropertyPath') : PropertyPath
}
_wsdlNameMap = InverseMap(_wsdlTypeMap)

for ((ns, name), typ) in _wsdlTypeMap.items():
   if typ is not NoneType:
      setattr(types, typ.__name__, typ)
      _wsdlTypeMapNSs.add(ns)
      arrayType = CreateArrayType(typ)
      setattr(types, Capitalize(typ.__name__) + "Array", arrayType)
      arrayName = "ArrayOf" + Capitalize(name)
      arrayNS = XMLNS_VMODL_BASE
      _SetWsdlType(arrayNS, arrayName, arrayType)
      _wsdlNameMap[arrayType] = (arrayNS, arrayName)
del name, typ

# unicode is mapped to wsdl name 'string' (Cannot put in wsdlTypeMap or name
# collision with non-unicode string)
_wsdlNameMap[unicode] = (XMLNS_XSD, 'string')
_wsdlNameMap[CreateArrayType(unicode)] = (XMLNS_VMODL_BASE, 'ArrayOfString')

# _wsdlMethodNSs store namespaces added to _wsdlMethodMap in _SetWsdlMethod
_wsdlMethodNSs = set()
_wsdlMethodMap = {}

# Registering the classes defined in VmomiSupport in the definition maps
CreateManagedType(ManagedObject.__name__, ManagedObject._wsdlName, None,
                  ManagedObject._version, [], [])
_AddType(ManagedObject)
setattr(types, ManagedObject.__name__, ManagedObject)

CreateDataType(DataObject.__name__, DataObject._wsdlName, None,
               DataObject._version, [])
_AddType(DataObject)
setattr(types, DataObject.__name__, DataObject)

## Vmodl types
vmodlTypes = {
   # Note: xsd has no void type. This is a hack from before. Can be removed?
   "void"   : GetWsdlType(XMLNS_XSD, 'void'),
   "anyType": GetWsdlType(XMLNS_XSD, 'anyType'),
   "string" : GetWsdlType(XMLNS_XSD, 'string'),
   "bool"   : GetWsdlType(XMLNS_XSD, 'boolean'),
   "boolean": GetWsdlType(XMLNS_XSD, 'boolean'),
   "byte"   : GetWsdlType(XMLNS_XSD, 'byte'),
   "short"  : GetWsdlType(XMLNS_XSD, 'short'),
   "int"    : GetWsdlType(XMLNS_XSD, 'int'),
   "long"   : GetWsdlType(XMLNS_XSD, 'long'),
   "float"  : GetWsdlType(XMLNS_XSD, 'float'),
   "double" : GetWsdlType(XMLNS_XSD, 'double'),
   "Link"   : GetWsdlType(XMLNS_XSD, 'Link'),
   "vmodl.URI"        : GetWsdlType(XMLNS_XSD, 'anyURI'),
   "vmodl.Binary"     : GetWsdlType(XMLNS_XSD, 'base64Binary'),
   "vmodl.DateTime"   : GetWsdlType(XMLNS_XSD, 'dateTime'),
   "vmodl.TypeName"   : GetWsdlType(XMLNS_VMODL_BASE, 'TypeName'),
   "vmodl.MethodName" : GetWsdlType(XMLNS_VMODL_BASE, 'MethodName'),
   "vmodl.DataObject" : GetWsdlType(XMLNS_VMODL_BASE, 'DataObject'),
   "vmodl.ManagedObject" : GetWsdlType(XMLNS_VMODL_BASE, 'ManagedObject'),
   "vmodl.PropertyPath"  : GetWsdlType(XMLNS_VMODL_BASE, 'PropertyPath'),
}
vmodlNames = {}

## Add array type into special names
for name, typ in vmodlTypes.copy().iteritems():
   if typ is not NoneType:
      try:
         arrayType = typ.Array
      except AttributeError:
         wsdlName = GetWsdlName(typ)
         arrayNS = XMLNS_VMODL_BASE
         arrayType = GetWsdlType(arrayNS, "ArrayOf" + Capitalize(wsdlName))
      arrayName = name + "[]"
      vmodlTypes[arrayName] = arrayType

   # Set type to vmodl name map
   vmodlNames[typ] = name
   vmodlNames[arrayType] = arrayName
del name, typ


## Get type from vmodl name
#
# @param name vmodl name
# @return vmodl type
def GetVmodlType(name):
   """ Get type from vmodl name """

   # If the input is already a type, just return
   if isinstance(name, type):
      return name

   # Try to get type from vmodl type names table
   typ = vmodlTypes.get(name)
   if typ:
      return typ

   # Else get the type from the _wsdlTypeMap
   isArray = name.endswith("[]")
   if isArray:
      name = name[:-2]
   ns, wsdlName = _GetWsdlInfo(name)
   try:
      typ = GetWsdlType(ns, wsdlName)
   except KeyError:
      raise KeyError(name)
   if typ:
      return isArray and typ.Array or typ
   else:
      raise KeyError(name)

## Get VMODL type name from type
#
# @param typ vmodl type
# @return vmodl name
def GetVmodlName(typ):
   """ Get vmodl type name from type """
   try:
      return vmodlNames[typ]
   except KeyError:
      return typ.__name__

## Get Wsdl type name from Python type name
#
# @param pythonTypeName Python type name
# @return wsdl type name
def GetWsdlTypeName(pythonTypeName):
   try:
      typ = GetVmodlType(pythonTypeName)
   except KeyError:
      raise NameError('No type found with name ' + pythonTypeName)
   return GetWsdlName(typ)

## Get Wsdl method name from Python method name
#
# @param pythonTypeName Python type name
# @param pythonMethodName Python method name
# @return wsdl method name
def GetWsdlMethodName(pythonTypeName, pythonMethodName):
   try:
      typ = GetVmodlType(pythonTypeName)
      _, _, _, _, _, methods = _wsdlDefMap[GetQualifiedWsdlName(typ)]
   except KeyError:
      raise NameError('No type found with name ' + pythonTypeName)
   uncapPythonMethodName = Uncapitalize(pythonMethodName)
   for method in methods:
      mVmodl, mWsdl, _, _, _, _, _ = method
      if mVmodl == uncapPythonMethodName or mVmodl == pythonMethodName:
         return mWsdl
   raise NameError('No method found with name ' + pythonMethodName)

## Get Python type name from Wsdl type name
#
# @param ns wsdl namespace
# @param wsdlTypeName wsdl type name
# @return python type name
def GetPythonTypeName(wsdlTypeName, ns):
   try:
      typ = GetWsdlType(ns, wsdlTypeName)
   except KeyError:
      raise NameError('No type found with namespace %s and name %s' % (ns, wsdlTypeName))
   return GetVmodlName(typ)

## Get Python method name from Wsdl method name
#
# @param ns wsdl namespace
# @param wsdlTypeName wsdl type name
# @param wsdlMethodName wsdl method name
# @return python method name
def GetPythonMethodName(wsdlTypeName, ns, wsdlMethodName):
   try:
      _, _, _, _, _, methods = _wsdlDefMap[(ns, wsdlTypeName)]
   except KeyError:
      raise NameError('No type found with namespace %s and name %s' % (ns, wsdlTypeName))
   for method in methods:
      mVmodl, mWsdl, _, _, _, _, _ = method
      if mWsdl == wsdlMethodName:
         return Capitalize(mVmodl)
   raise NameError('No method found with name ' + wsdlMethodName)

## String only dictionary: same as dict, except it only accept string as value
#
class StringDict(dict):
   """
   String only dictionary: same as dict, except it only accept string as value

   dict in python is kind of strange. U cannot just override __setitem__, as
   __init__, update, and setdefault all bypass __setitem__. When override,
   we have to override all three together
   """
   def __init__(self, *args, **kwargs):
      dict.__init__(self)
      self.update(*args, **kwargs)

   # Same as dict setdefault, except this will call through our __setitem__
   def update(self, *args, **kwargs):
      for k, v in dict(*args, **kwargs).iteritems():
         self[k] = v

   # Same as dict setdefault, except this will call through our __setitem__
   def setdefault(self, key, val=None):
      if key in self:
         return self[key]
      else:
         self[key] = val
         return val

   def __setitem__(self, key, val):
      """x.__setitem__(i, y) <==> x[i]=y, where y must be a string"""
      if not isinstance(val, basestring):
         raise TypeError("key %s has non-string value %s of %s" %
                                                         (key, val, type(val)))
      return dict.__setitem__(self, key, val)

## Retrieves the actual vmodl name from type dictionaries
#
#  Note: Must be holding the _lazyLock
# @param name upcapitalized vmodl name
# @return vmodl name
def _GetActualName(name):
   """ Note: Must be holding the _lazyLock """
   if _allowCapitalizedNames:
      name = UncapitalizeVmodlName(name)
   for defMap in _dataDefMap, _managedDefMap, _enumDefMap:
      dic = defMap.get(name)
      if dic:
         return dic[0]
   return None

## Retrieves the actual wsdl name from type dictionaries
#
# @param name upcapitalized vmodl name
# @return (wsdl namespace, wsdl name)
def _GetWsdlInfo(name):
   if _allowCapitalizedNames:
      name = UncapitalizeVmodlName(name)

   with _lazyLock:
      # For data and managed objects, emitter puts version in field #3 and in
      # enum objects, it is in field #2. So, have to handle them differently
      for defMap in _dataDefMap, _managedDefMap:
         dic = defMap.get(name)
         if dic:
            return GetWsdlNamespace(dic[3]), dic[1]

      dic = _enumDefMap.get(name)
      if dic:
         return GetWsdlNamespace(dic[2]), dic[1]
      return None, None

## Checks if the definition exists for a vmodl name
#
# @param name vmodl name
# @return True if name exists, False otherwise
def TypeDefExists(name):
   # Check if is one of the primitive types
   typ = vmodlTypes.get(name)
   if typ:
      return True

   # Check if it's type definition is loaded in the dictionaries
   if name.endswith("[]"):
      name = name[:-2]

   with _lazyLock:
      actualName = _GetActualName(name)
   return actualName is not None

# Thread local for req context
_threadLocalContext = threading.local()

# Get the RequestContext for the current thread
#
def GetRequestContext():
   """ Get the RequestContext for the current thread """
   global _threadLocalContext
   return _threadLocalContext.__dict__.setdefault('reqCtx', StringDict())

# Get the Http context for the current thread
#
def GetHttpContext():
   """ Get the Http context for the current thread """
   global _threadLocalContext
   return _threadLocalContext.__dict__.setdefault('httpCtx', dict())

## Class that resolves links
class LinkResolver:
   ## Constructor
   #
   # @param self self
   # @param scope DataObject to be used against for resolving links
   def __init__(self, scope):
      self.linkables = {}
      self._VisitDataObject(scope)

   ## Visit a DataObject and add it to linkable if it is one. Also
   #  visit its properties that are DataObjects
   #
   # @param self self
   # @param obj DataObject to be visited
   def _VisitDataObject(self, obj):
      if isinstance(obj, DataObject):
         for prop in obj._GetPropertyList():
            if issubclass(prop.type, list):
               for dataObj in getattr(obj, prop.name):
                  if (prop.flags & F_LINKABLE):
                     self._AddLinkable(dataObj)
                  self._VisitDataObject(dataObj)
            else:
               dataObj = getattr(obj, prop.name)
               if (prop.flags & F_LINKABLE):
                  self._AddLinkable(dataObj)
               self._VisitDataObject(dataObj)
      elif isinstance(obj, list):
         for dataObj in obj:
            self._VisitDataObject(dataObj)

   ## Adds a DataObject to linkable dictionary using its key
   #
   # @param self self
   # @param obj DataObject to be added to linkable
   def _AddLinkable(self, obj):
      key = getattr(obj, "key")
      if key and key != '':
         if self.linkables.has_key(key):
            #duplicate key present
            raise AttributeError(key)
         else:
            self.linkables[key] = obj
      else:
         #empty key
         raise AttributeError(key)

   ## Resolves a key by looking up linkable dictionary
   #
   # @param self self
   # @param key Key to be resolved
   def ResolveLink(self, key):
      val = self.linkables[key]
      return val

   ## Resolves a list of keys by resolving each key
   #
   # @param self self
   # @param keys keys to be resolved
   def ResolveLinks(self, keys):
      val = [self.linkables[k] for k in keys]
      return val

## Resolves a link key using the object provided as its scope by creating a
#  link resolver object
#
# @param key Key to be resolved
# @param obj DataObject to be used against for resolving links
def ResolveLink(key, obj):
   if obj is None:
      return None
   linkResolver = LinkResolver(obj)
   return linkResolver.ResolveLink(key)

## Resolves a list of link keys using the object provided as its scope by creating a
#  link resolver object
#
# @param keys keys to be resolved
# @param obj DataObject to be used against for resolving links
def ResolveLinks(keys, obj):
   if obj is None:
      return None
   linkResolver = LinkResolver(obj)
   return linkResolver.ResolveLinks(keys)