"""
This class is defined to override standard pickle functionality
The goals of it follow:
-Serialize lambdas and nested functions to compiled byte code
-Deal with main module correctly
-Deal with other non-serializable objects
It does not include an unpickler, as standard python unpickling suffices.
This module was extracted from the `cloud` package, developed by `PiCloud, Inc.
<http://www.picloud.com>`_.
Copyright (c) 2012, Regents of the University of California.
Copyright (c) 2009 `PiCloud, Inc. <http://www.picloud.com>`_.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of the University of California, Berkeley nor the
names of its contributors may be used to endorse or promote
products derived from this software without specific prior written
permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""
from __future__ import print_function
import operator
import opcode
import os
import io
import pickle
import struct
import sys
import types
from functools import partial
import itertools
import dis
import traceback
import weakref
if sys.version < '3':
from pickle import Pickler
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
PY3 = False
else:
types.ClassType = type
from pickle import _Pickler as Pickler
from io import BytesIO as StringIO
PY3 = True
#relevant opcodes
STORE_GLOBAL = opcode.opmap['STORE_GLOBAL']
DELETE_GLOBAL = opcode.opmap['DELETE_GLOBAL']
LOAD_GLOBAL = opcode.opmap['LOAD_GLOBAL']
GLOBAL_OPS = (STORE_GLOBAL, DELETE_GLOBAL, LOAD_GLOBAL)
HAVE_ARGUMENT = dis.HAVE_ARGUMENT
EXTENDED_ARG = dis.EXTENDED_ARG
def islambda(func):
return getattr(func,'__name__') == '<lambda>'
_BUILTIN_TYPE_NAMES = {}
for k, v in types.__dict__.items():
if type(v) is type:
_BUILTIN_TYPE_NAMES[v] = k
def _builtin_type(name):
return getattr(types, name)
if sys.version_info < (3, 4):
def _walk_global_ops(code):
"""
Yield (opcode, argument number) tuples for all
global-referencing instructions in *code*.
"""
code = getattr(code, 'co_code', b'')
if not PY3:
code = map(ord, code)
n = len(code)
i = 0
extended_arg = 0
while i < n:
op = code[i]
i += 1
if op >= HAVE_ARGUMENT:
oparg = code[i] + code[i + 1] * 256 + extended_arg
extended_arg = 0
i += 2
if op == EXTENDED_ARG:
extended_arg = oparg * 65536
if op in GLOBAL_OPS:
yield op, oparg
else:
def _walk_global_ops(code):
"""
Yield (opcode, argument number) tuples for all
global-referencing instructions in *code*.
"""
for instr in dis.get_instructions(code):
op = instr.opcode
if op in GLOBAL_OPS:
yield op, instr.arg
class CloudPickler(Pickler):
dispatch = Pickler.dispatch.copy()
def __init__(self, file, protocol=None):
Pickler.__init__(self, file, protocol)
# set of modules to unpickle
self.modules = set()
# map ids to dictionary. used to ensure that functions can share global env
self.globals_ref = {}
def dump(self, obj):
self.inject_addons()
try:
return Pickler.dump(self, obj)
except RuntimeError as e:
if 'recursion' in e.args[0]:
msg = """Could not pickle object as excessively deep recursion required."""
raise pickle.PicklingError(msg)
except pickle.PickleError:
raise
except Exception as e:
if "'i' format requires" in e.message:
msg = "Object too large to serialize: " + e.message
else:
msg = "Could not serialize object: " + e.__class__.__name__ + ": " + e.message
print_exec(sys.stderr)
raise pickle.PicklingError(msg)
def save_memoryview(self, obj):
"""Fallback to save_string"""
Pickler.save_string(self, str(obj))
def save_buffer(self, obj):
"""Fallback to save_string"""
Pickler.save_string(self,str(obj))
if PY3:
dispatch[memoryview] = save_memoryview
else:
dispatch[buffer] = save_buffer
def save_unsupported(self, obj):
raise pickle.PicklingError("Cannot pickle objects of type %s" % type(obj))
dispatch[types.GeneratorType] = save_unsupported
# itertools objects do not pickle!
for v in itertools.__dict__.values():
if type(v) is type:
dispatch[v] = save_unsupported
def save_module(self, obj):
"""
Save a module as an import
"""
self.modules.add(obj)
self.save_reduce(subimport, (obj.__name__,), obj=obj)
dispatch[types.ModuleType] = save_module
def save_codeobject(self, obj):
"""
Save a code object
"""
if PY3:
args = (
obj.co_argcount, obj.co_kwonlyargcount, obj.co_nlocals, obj.co_stacksize,
obj.co_flags, obj.co_code, obj.co_consts, obj.co_names, obj.co_varnames,
obj.co_filename, obj.co_name, obj.co_firstlineno, obj.co_lnotab, obj.co_freevars,
obj.co_cellvars
)
else:
args = (
obj.co_argcount, obj.co_nlocals, obj.co_stacksize, obj.co_flags, obj.co_code,
obj.co_consts, obj.co_names, obj.co_varnames, obj.co_filename, obj.co_name,
obj.co_firstlineno, obj.co_lnotab, obj.co_freevars, obj.co_cellvars
)
self.save_reduce(types.CodeType, args, obj=obj)
dispatch[types.CodeType] = save_codeobject
def save_function(self, obj, name=None):
""" Registered with the dispatch to handle all function types.
Determines what kind of function obj is (e.g. lambda, defined at
interactive prompt, etc) and handles the pickling appropriately.
"""
write = self.write
if name is None:
name = obj.__name__
try:
# whichmodule() could fail, see
# https://bitbucket.org/gutworth/six/issues/63/importing-six-breaks-pickling
modname = pickle.whichmodule(obj, name)
except Exception:
modname = None
# print('which gives %s %s %s' % (modname, obj, name))
try:
themodule = sys.modules[modname]
except KeyError:
# eval'd items such as namedtuple give invalid items for their function __module__
modname = '__main__'
if modname == '__main__':
themodule = None
if themodule:
self.modules.add(themodule)
if getattr(themodule, name, None) is obj:
return self.save_global(obj, name)
# if func is lambda, def'ed at prompt, is in main, or is nested, then
# we'll pickle the actual function object rather than simply saving a
# reference (as is done in default pickler), via save_function_tuple.
if islambda(obj) or obj.__code__.co_filename == '<stdin>' or themodule is None:
#print("save global", islambda(obj), obj.__code__.co_filename, modname, themodule)
self.save_function_tuple(obj)
return
else:
# func is nested
klass = getattr(themodule, name, None)
if klass is None or klass is not obj:
self.save_function_tuple(obj)
return
if obj.__dict__:
# essentially save_reduce, but workaround needed to avoid recursion
self.save(_restore_attr)
write(pickle.MARK + pickle.GLOBAL + modname + '\n' + name + '\n')
self.memoize(obj)
self.save(obj.__dict__)
write(pickle.TUPLE + pickle.REDUCE)
else:
write(pickle.GLOBAL + modname + '\n' + name + '\n')
self.memoize(obj)
dispatch[types.FunctionType] = save_function
def save_function_tuple(self, func):
""" Pickles an actual func object.
A func comprises: code, globals, defaults, closure, and dict. We
extract and save these, injecting reducing functions at certain points
to recreate the func object. Keep in mind that some of these pieces
can contain a ref to the func itself. Thus, a naive save on these
pieces could trigger an infinite loop of save's. To get around that,
we first create a skeleton func object using just the code (this is
safe, since this won't contain a ref to the func), and memoize it as
soon as it's created. The other stuff can then be filled in later.
"""
save = self.save
write = self.write
code, f_globals, defaults, closure, dct, base_globals = self.extract_func_data(func)
save(_fill_function) # skeleton function updater
write(pickle.MARK) # beginning of tuple that _fill_function expects
# create a skeleton function object and memoize it
save(_make_skel_func)
save((code, closure, base_globals))
write(pickle.REDUCE)
self.memoize(func)
# save the rest of the func data needed by _fill_function
save(f_globals)
save(defaults)
save(dct)
save(func.__module__)
write(pickle.TUPLE)
write(pickle.REDUCE) # applies _fill_function on the tuple
_extract_code_globals_cache = (
weakref.WeakKeyDictionary()
if sys.version_info >= (2, 7) and not hasattr(sys, "pypy_version_info")
else {})
@classmethod
def extract_code_globals(cls, co):
"""
Find all globals names read or written to by codeblock co
"""
out_names = cls._extract_code_globals_cache.get(co)
if out_names is None:
try:
names = co.co_names
except AttributeError:
# PyPy "builtin-code" object
out_names = set()
else:
out_names = set(names[oparg]
for op, oparg in _walk_global_ops(co))
# see if nested function have any global refs
if co.co_consts:
for const in co.co_consts:
if type(const) is types.CodeType:
out_names |= cls.extract_code_globals(const)
cls._extract_code_globals_cache[co] = out_names
return out_names
def extract_func_data(self, func):
"""
Turn the function into a tuple of data necessary to recreate it:
code, globals, defaults, closure, dict
"""
code = func.__code__
# extract all global ref's
func_global_refs = self.extract_code_globals(code)
# process all variables referenced by global environment
f_globals = {}
for var in func_global_refs:
if var in func.__globals__:
f_globals[var] = func.__globals__[var]
# defaults requires no processing
defaults = func.__defaults__
# process closure
closure = [c.cell_contents for c in func.__closure__] if func.__closure__ else []
# save the dict
dct = func.__dict__
base_globals = self.globals_ref.get(id(func.__globals__), {})
self.globals_ref[id(func.__globals__)] = base_globals
return (code, f_globals, defaults, closure, dct, base_globals)
def save_builtin_function(self, obj):
if obj.__module__ is "__builtin__":
return self.save_global(obj)
return self.save_function(obj)
dispatch[types.BuiltinFunctionType] = save_builtin_function
def save_global(self, obj, name=None, pack=struct.pack):
if obj.__module__ == "__builtin__" or obj.__module__ == "builtins":
if obj in _BUILTIN_TYPE_NAMES:
return self.save_reduce(_builtin_type, (_BUILTIN_TYPE_NAMES[obj],), obj=obj)
if name is None:
name = obj.__name__
modname = getattr(obj, "__module__", None)
if modname is None:
try:
# whichmodule() could fail, see
# https://bitbucket.org/gutworth/six/issues/63/importing-six-breaks-pickling
modname = pickle.whichmodule(obj, name)
except Exception:
modname = '__main__'
if modname == '__main__':
themodule = None
else:
__import__(modname)
themodule = sys.modules[modname]
self.modules.add(themodule)
if hasattr(themodule, name) and getattr(themodule, name) is obj:
return Pickler.save_global(self, obj, name)
typ = type(obj)
if typ is not obj and isinstance(obj, (type, types.ClassType)):
d = dict(obj.__dict__) # copy dict proxy to a dict
if not isinstance(d.get('__dict__', None), property):
# don't extract dict that are properties
d.pop('__dict__', None)
d.pop('__weakref__', None)
# hack as __new__ is stored differently in the __dict__
new_override = d.get('__new__', None)
if new_override:
d['__new__'] = obj.__new__
# workaround for namedtuple (hijacked by PySpark)
if getattr(obj, '_is_namedtuple_', False):
self.save_reduce(_load_namedtuple, (obj.__name__, obj._fields))
return
self.save(_load_class)
self.save_reduce(typ, (obj.__name__, obj.__bases__, {"__doc__": obj.__doc__}), obj=obj)
d.pop('__doc__', None)
# handle property and staticmethod
dd = {}
for k, v in d.items():
if isinstance(v, property):
k = ('property', k)
v = (v.fget, v.fset, v.fdel, v.__doc__)
elif isinstance(v, staticmethod) and hasattr(v, '__func__'):
k = ('staticmethod', k)
v = v.__func__
elif isinstance(v, classmethod) and hasattr(v, '__func__'):
k = ('classmethod', k)
v = v.__func__
dd[k] = v
self.save(dd)
self.write(pickle.TUPLE2)
self.write(pickle.REDUCE)
else:
raise pickle.PicklingError("Can't pickle %r" % obj)
dispatch[type] = save_global
dispatch[types.ClassType] = save_global
def save_instancemethod(self, obj):
# Memoization rarely is ever useful due to python bounding
if PY3:
self.save_reduce(types.MethodType, (obj.__func__, obj.__self__), obj=obj)
else:
self.save_reduce(types.MethodType, (obj.__func__, obj.__self__, obj.__self__.__class__),
obj=obj)
dispatch[types.MethodType] = save_instancemethod
def save_inst(self, obj):
"""Inner logic to save instance. Based off pickle.save_inst
Supports __transient__"""
cls = obj.__class__
memo = self.memo
write = self.write
save = self.save
if hasattr(obj, '__getinitargs__'):
args = obj.__getinitargs__()
len(args) # XXX Assert it's a sequence
pickle._keep_alive(args, memo)
else:
args = ()
write(pickle.MARK)
if self.bin:
save(cls)
for arg in args:
save(arg)
write(pickle.OBJ)
else:
for arg in args:
save(arg)
write(pickle.INST + cls.__module__ + '\n' + cls.__name__ + '\n')
self.memoize(obj)
try:
getstate = obj.__getstate__
except AttributeError:
stuff = obj.__dict__
#remove items if transient
if hasattr(obj, '__transient__'):
transient = obj.__transient__
stuff = stuff.copy()
for k in list(stuff.keys()):
if k in transient:
del stuff[k]
else:
stuff = getstate()
pickle._keep_alive(stuff, memo)
save(stuff)
write(pickle.BUILD)
if not PY3:
dispatch[types.InstanceType] = save_inst
def save_property(self, obj):
# properties not correctly saved in python
self.save_reduce(property, (obj.fget, obj.fset, obj.fdel, obj.__doc__), obj=obj)
dispatch[property] = save_property
def save_itemgetter(self, obj):
"""itemgetter serializer (needed for namedtuple support)"""
class Dummy:
def __getitem__(self, item):
return item
items = obj(Dummy())
if not isinstance(items, tuple):
items = (items, )
return self.save_reduce(operator.itemgetter, items)
if type(operator.itemgetter) is type:
dispatch[operator.itemgetter] = save_itemgetter
def save_attrgetter(self, obj):
"""attrgetter serializer"""
class Dummy(object):
def __init__(self, attrs, index=None):
self.attrs = attrs
self.index = index
def __getattribute__(self, item):
attrs = object.__getattribute__(self, "attrs")
index = object.__getattribute__(self, "index")
if index is None:
index = len(attrs)
attrs.append(item)
else:
attrs[index] = ".".join([attrs[index], item])
return type(self)(attrs, index)
attrs = []
obj(Dummy(attrs))
return self.save_reduce(operator.attrgetter, tuple(attrs))
if type(operator.attrgetter) is type:
dispatch[operator.attrgetter] = save_attrgetter
def save_reduce(self, func, args, state=None,
listitems=None, dictitems=None, obj=None):
"""Modified to support __transient__ on new objects
Change only affects protocol level 2 (which is always used by PiCloud"""
# Assert that args is a tuple or None
if not isinstance(args, tuple):
raise pickle.PicklingError("args from reduce() should be a tuple")
# Assert that func is callable
if not hasattr(func, '__call__'):
raise pickle.PicklingError("func from reduce should be callable")
save = self.save
write = self.write
# Protocol 2 special case: if func's name is __newobj__, use NEWOBJ
if self.proto >= 2 and getattr(func, "__name__", "") == "__newobj__":
#Added fix to allow transient
cls = args[0]
if not hasattr(cls, "__new__"):
raise pickle.PicklingError(
"args[0] from __newobj__ args has no __new__")
if obj is not None and cls is not obj.__class__:
raise pickle.PicklingError(
"args[0] from __newobj__ args has the wrong class")
args = args[1:]
save(cls)
#Don't pickle transient entries
if hasattr(obj, '__transient__'):
transient = obj.__transient__
state = state.copy()
for k in list(state.keys()):
if k in transient:
del state[k]
save(args)
write(pickle.NEWOBJ)
else:
save(func)
save(args)
write(pickle.REDUCE)
if obj is not None:
self.memoize(obj)
# More new special cases (that work with older protocols as
# well): when __reduce__ returns a tuple with 4 or 5 items,
# the 4th and 5th item should be iterators that provide list
# items and dict items (as (key, value) tuples), or None.
if listitems is not None:
self._batch_appends(listitems)
if dictitems is not None:
self._batch_setitems(dictitems)
if state is not None:
save(state)
write(pickle.BUILD)
def save_partial(self, obj):
"""Partial objects do not serialize correctly in python2.x -- this fixes the bugs"""
self.save_reduce(_genpartial, (obj.func, obj.args, obj.keywords))
if sys.version_info < (2,7): # 2.7 supports partial pickling
dispatch[partial] = save_partial
def save_file(self, obj):
"""Save a file"""
try:
import StringIO as pystringIO #we can't use cStringIO as it lacks the name attribute
except ImportError:
import io as pystringIO
if not hasattr(obj, 'name') or not hasattr(obj, 'mode'):
raise pickle.PicklingError("Cannot pickle files that do not map to an actual file")
if obj is sys.stdout:
return self.save_reduce(getattr, (sys,'stdout'), obj=obj)
if obj is sys.stderr:
return self.save_reduce(getattr, (sys,'stderr'), obj=obj)
if obj is sys.stdin:
raise pickle.PicklingError("Cannot pickle standard input")
if hasattr(obj, 'isatty') and obj.isatty():
raise pickle.PicklingError("Cannot pickle files that map to tty objects")
if 'r' not in obj.mode:
raise pickle.PicklingError("Cannot pickle files that are not opened for reading")
name = obj.name
try:
fsize = os.stat(name).st_size
except OSError:
raise pickle.PicklingError("Cannot pickle file %s as it cannot be stat" % name)
if obj.closed:
#create an empty closed string io
retval = pystringIO.StringIO("")
retval.close()
elif not fsize: #empty file
retval = pystringIO.StringIO("")
try:
tmpfile = file(name)
tst = tmpfile.read(1)
except IOError:
raise pickle.PicklingError("Cannot pickle file %s as it cannot be read" % name)
tmpfile.close()
if tst != '':
raise pickle.PicklingError("Cannot pickle file %s as it does not appear to map to a physical, real file" % name)
else:
try:
tmpfile = file(name)
contents = tmpfile.read()
tmpfile.close()
except IOError:
raise pickle.PicklingError("Cannot pickle file %s as it cannot be read" % name)
retval = pystringIO.StringIO(contents)
curloc = obj.tell()
retval.seek(curloc)
retval.name = name
self.save(retval)
self.memoize(obj)
if PY3:
dispatch[io.TextIOWrapper] = save_file
else:
dispatch[file] = save_file
"""Special functions for Add-on libraries"""
def inject_numpy(self):
numpy = sys.modules.get('numpy')
if not numpy or not hasattr(numpy, 'ufunc'):
return
self.dispatch[numpy.ufunc] = self.__class__.save_ufunc
def save_ufunc(self, obj):
"""Hack function for saving numpy ufunc objects"""
name = obj.__name__
numpy_tst_mods = ['numpy', 'scipy.special']
for tst_mod_name in numpy_tst_mods:
tst_mod = sys.modules.get(tst_mod_name, None)
if tst_mod and name in tst_mod.__dict__:
return self.save_reduce(_getobject, (tst_mod_name, name))
raise pickle.PicklingError('cannot save %s. Cannot resolve what module it is defined in'
% str(obj))
def inject_addons(self):
"""Plug in system. Register additional pickling functions if modules already loaded"""
self.inject_numpy()
# Shorthands for legacy support
def dump(obj, file, protocol=2):
CloudPickler(file, protocol).dump(obj)
def dumps(obj, protocol=2):
file = StringIO()
cp = CloudPickler(file,protocol)
cp.dump(obj)
return file.getvalue()
#hack for __import__ not working as desired
def subimport(name):
__import__(name)
return sys.modules[name]
# restores function attributes
def _restore_attr(obj, attr):
for key, val in attr.items():
setattr(obj, key, val)
return obj
def _get_module_builtins():
return pickle.__builtins__
def print_exec(stream):
ei = sys.exc_info()
traceback.print_exception(ei[0], ei[1], ei[2], None, stream)
def _modules_to_main(modList):
"""Force every module in modList to be placed into main"""
if not modList:
return
main = sys.modules['__main__']
for modname in modList:
if type(modname) is str:
try:
mod = __import__(modname)
except Exception as e:
sys.stderr.write('warning: could not import %s\n. '
'Your function may unexpectedly error due to this import failing;'
'A version mismatch is likely. Specific error was:\n' % modname)
print_exec(sys.stderr)
else:
setattr(main, mod.__name__, mod)
#object generators:
def _genpartial(func, args, kwds):
if not args:
args = ()
if not kwds:
kwds = {}
return partial(func, *args, **kwds)
def _fill_function(func, globals, defaults, dict, module):
""" Fills in the rest of function data into the skeleton function object
that were created via _make_skel_func().
"""
func.__globals__.update(globals)
func.__defaults__ = defaults
func.__dict__ = dict
func.__module__ = module
return func
def _make_cell(value):
return (lambda: value).__closure__[0]
def _reconstruct_closure(values):
return tuple([_make_cell(v) for v in values])
def _make_skel_func(code, closures, base_globals = None):
""" Creates a skeleton function object that contains just the provided
code and the correct number of cells in func_closure. All other
func attributes (e.g. func_globals) are empty.
"""
closure = _reconstruct_closure(closures) if closures else None
if base_globals is None:
base_globals = {}
base_globals['__builtins__'] = __builtins__
return types.FunctionType(code, base_globals,
None, None, closure)
def _load_class(cls, d):
"""
Loads additional properties into class `cls`.
"""
for k, v in d.items():
if isinstance(k, tuple):
typ, k = k
if typ == 'property':
v = property(*v)
elif typ == 'staticmethod':
v = staticmethod(v)
elif typ == 'classmethod':
v = classmethod(v)
setattr(cls, k, v)
return cls
def _load_namedtuple(name, fields):
"""
Loads a class generated by namedtuple
"""
from collections import namedtuple
return namedtuple(name, fields)
"""Constructors for 3rd party libraries
Note: These can never be renamed due to client compatibility issues"""
def _getobject(modname, attribute):
mod = __import__(modname, fromlist=[attribute])
return mod.__dict__[attribute]