add passlib for sha-512 salted hash generation

passlib/utils/compat.py

@@ -0,0 +1,436 @@
+"""passlib.utils.compat - python 2/3 compatibility helpers"""
+#=============================================================================
+# figure out what we're running
+#=============================================================================
+
+#------------------------------------------------------------------------
+# python version
+#------------------------------------------------------------------------
+import sys
+PY2 = sys.version_info < (3,0)
+PY3 = sys.version_info >= (3,0)
+PY_MAX_25 = sys.version_info < (2,6) # py 2.5 or earlier
+PY27 = sys.version_info[:2] == (2,7) # supports last 2.x release
+PY_MIN_32 = sys.version_info >= (3,2) # py 3.2 or later
+
+#------------------------------------------------------------------------
+# python implementation
+#------------------------------------------------------------------------
+PYPY = hasattr(sys, "pypy_version_info")
+JYTHON = sys.platform.startswith('java')
+
+#------------------------------------------------------------------------
+# capabilities
+#------------------------------------------------------------------------
+
+# __dir__() added in py2.6
+SUPPORTS_DIR_METHOD = not PY_MAX_25 and not (PYPY and sys.pypy_version_info < (1,6))
+
+#=============================================================================
+# common imports
+#=============================================================================
+import logging; log = logging.getLogger(__name__)
+if PY3:
+    import builtins
+else:
+    import __builtin__ as builtins
+
+def add_doc(obj, doc):
+    """add docstring to an object"""
+    obj.__doc__ = doc
+
+#=============================================================================
+# the default exported vars
+#=============================================================================
+__all__ = [
+    # python versions
+    'PY2', 'PY3', 'PY_MAX_25', 'PY27', 'PY_MIN_32',
+
+    # io
+    'BytesIO', 'StringIO', 'NativeStringIO', 'SafeConfigParser',
+    'print_',
+
+    # type detection
+##    'is_mapping',
+    'callable',
+    'int_types',
+    'num_types',
+    'base_string_types',
+
+    # unicode/bytes types & helpers
+    'u', 'b',
+    'unicode', 'bytes',
+    'uascii_to_str', 'bascii_to_str',
+    'str_to_uascii', 'str_to_bascii',
+    'join_unicode', 'join_bytes',
+    'join_byte_values', 'join_byte_elems',
+    'byte_elem_value',
+    'iter_byte_values',
+
+    # iteration helpers
+    'irange', #'lrange',
+    'imap', 'lmap',
+    'iteritems', 'itervalues',
+    'next',
+
+    # introspection
+    'exc_err', 'get_method_function', 'add_doc',
+]
+
+# begin accumulating mapping of lazy-loaded attrs,
+# 'merged' into module at bottom
+_lazy_attrs = dict()
+
+#=============================================================================
+# unicode & bytes types
+#=============================================================================
+if PY3:
+    unicode = str
+    bytes = builtins.bytes
+
+    def u(s):
+        assert isinstance(s, str)
+        return s
+
+    def b(s):
+        assert isinstance(s, str)
+        return s.encode("latin-1")
+
+    base_string_types = (unicode, bytes)
+
+else:
+    unicode = builtins.unicode
+    bytes = str if PY_MAX_25 else builtins.bytes
+
+    def u(s):
+        assert isinstance(s, str)
+        return s.decode("unicode_escape")
+
+    def b(s):
+        assert isinstance(s, str)
+        return s
+
+    base_string_types = basestring
+
+#=============================================================================
+# unicode & bytes helpers
+#=============================================================================
+# function to join list of unicode strings
+join_unicode = u('').join
+
+# function to join list of byte strings
+join_bytes = b('').join
+
+if PY3:
+    def uascii_to_str(s):
+        assert isinstance(s, unicode)
+        return s
+
+    def bascii_to_str(s):
+        assert isinstance(s, bytes)
+        return s.decode("ascii")
+
+    def str_to_uascii(s):
+        assert isinstance(s, str)
+        return s
+
+    def str_to_bascii(s):
+        assert isinstance(s, str)
+        return s.encode("ascii")
+
+    join_byte_values = join_byte_elems = bytes
+
+    def byte_elem_value(elem):
+        assert isinstance(elem, int)
+        return elem
+
+    def iter_byte_values(s):
+        assert isinstance(s, bytes)
+        return s
+
+    def iter_byte_chars(s):
+        assert isinstance(s, bytes)
+        # FIXME: there has to be a better way to do this
+        return (bytes([c]) for c in s)
+
+else:
+    def uascii_to_str(s):
+        assert isinstance(s, unicode)
+        return s.encode("ascii")
+
+    def bascii_to_str(s):
+        assert isinstance(s, bytes)
+        return s
+
+    def str_to_uascii(s):
+        assert isinstance(s, str)
+        return s.decode("ascii")
+
+    def str_to_bascii(s):
+        assert isinstance(s, str)
+        return s
+
+    def join_byte_values(values):
+        return join_bytes(chr(v) for v in values)
+
+    join_byte_elems = join_bytes
+
+    byte_elem_value = ord
+
+    def iter_byte_values(s):
+        assert isinstance(s, bytes)
+        return (ord(c) for c in s)
+
+    def iter_byte_chars(s):
+        assert isinstance(s, bytes)
+        return s
+
+add_doc(uascii_to_str, "helper to convert ascii unicode -> native str")
+add_doc(bascii_to_str, "helper to convert ascii bytes -> native str")
+add_doc(str_to_uascii, "helper to convert ascii native str -> unicode")
+add_doc(str_to_bascii, "helper to convert ascii native str -> bytes")
+
+# join_byte_values -- function to convert list of ordinal integers to byte string.
+
+# join_byte_elems --  function to convert list of byte elements to byte string;
+#                 i.e. what's returned by ``b('a')[0]``...
+#                 this is b('a') under PY2, but 97 under PY3.
+
+# byte_elem_value -- function to convert byte element to integer -- a noop under PY3
+
+add_doc(iter_byte_values, "iterate over byte string as sequence of ints 0-255")
+add_doc(iter_byte_chars, "iterate over byte string as sequence of 1-byte strings")
+
+#=============================================================================
+# numeric
+#=============================================================================
+if PY3:
+    int_types = (int,)
+    num_types = (int, float)
+else:
+    int_types = (int, long)
+    num_types = (int, long, float)
+
+#=============================================================================
+# iteration helpers
+#
+# irange - range iterable / view (xrange under py2, range under py3)
+# lrange - range list (range under py2, list(range()) under py3)
+#
+# imap - map to iterator
+# lmap - map to list
+#=============================================================================
+if PY3:
+    irange = range
+    ##def lrange(*a,**k):
+    ##    return list(range(*a,**k))
+
+    def lmap(*a, **k):
+        return list(map(*a,**k))
+    imap = map
+
+    def iteritems(d):
+        return d.items()
+    def itervalues(d):
+        return d.values()
+
+    next_method_attr = "__next__"
+
+else:
+    irange = xrange
+    ##lrange = range
+
+    lmap = map
+    from itertools import imap
+
+    def iteritems(d):
+        return d.iteritems()
+    def itervalues(d):
+        return d.itervalues()
+
+    next_method_attr = "next"
+
+if PY_MAX_25:
+    _undef = object()
+    def next(itr, default=_undef):
+        "compat wrapper for next()"
+        if default is _undef:
+            return itr.next()
+        try:
+            return itr.next()
+        except StopIteration:
+            return default
+else:
+    next = builtins.next
+
+#=============================================================================
+# typing
+#=============================================================================
+##def is_mapping(obj):
+##    # non-exhaustive check, enough to distinguish from lists, etc
+##    return hasattr(obj, "items")
+
+if (3,0) <= sys.version_info < (3,2):
+    # callable isn't dead, it's just resting
+    from collections import Callable
+    def callable(obj):
+        return isinstance(obj, Callable)
+else:
+    callable = builtins.callable
+
+#=============================================================================
+# introspection
+#=============================================================================
+def exc_err():
+    "return current error object (to avoid try/except syntax change)"
+    return sys.exc_info()[1]
+
+if PY3:
+    method_function_attr = "__func__"
+else:
+    method_function_attr = "im_func"
+
+def get_method_function(func):
+    "given (potential) method, return underlying function"
+    return getattr(func, method_function_attr, func)
+
+#=============================================================================
+# input/output
+#=============================================================================
+if PY3:
+    _lazy_attrs = dict(
+        BytesIO="io.BytesIO",
+        UnicodeIO="io.StringIO",
+        NativeStringIO="io.StringIO",
+        SafeConfigParser="configparser.SafeConfigParser",
+    )
+    if sys.version_info >= (3,2):
+        # py32 renamed this, removing old ConfigParser
+        _lazy_attrs["SafeConfigParser"] = "configparser.ConfigParser"
+
+    print_ = getattr(builtins, "print")
+
+else:
+    _lazy_attrs = dict(
+        BytesIO="cStringIO.StringIO",
+        UnicodeIO="StringIO.StringIO",
+        NativeStringIO="cStringIO.StringIO",
+        SafeConfigParser="ConfigParser.SafeConfigParser",
+    )
+
+    def print_(*args, **kwds):
+        """The new-style print function."""
+        # extract kwd args
+        fp = kwds.pop("file", sys.stdout)
+        sep = kwds.pop("sep", None)
+        end = kwds.pop("end", None)
+        if kwds:
+            raise TypeError("invalid keyword arguments")
+
+        # short-circuit if no target
+        if fp is None:
+            return
+
+        # use unicode or bytes ?
+        want_unicode = isinstance(sep, unicode) or isinstance(end, unicode) or \
+                       any(isinstance(arg, unicode) for arg in args)
+
+        # pick default end sequence
+        if end is None:
+            end = u("\n") if want_unicode else "\n"
+        elif not isinstance(end, base_string_types):
+            raise TypeError("end must be None or a string")
+
+        # pick default separator
+        if sep is None:
+            sep = u(" ") if want_unicode else " "
+        elif not isinstance(sep, base_string_types):
+            raise TypeError("sep must be None or a string")
+
+        # write to buffer
+        first = True
+        write = fp.write
+        for arg in args:
+            if first:
+                first = False
+            else:
+                write(sep)
+            if not isinstance(arg, basestring):
+                arg = str(arg)
+            write(arg)
+        write(end)
+
+#=============================================================================
+# lazy overlay module
+#=============================================================================
+from types import ModuleType
+
+def _import_object(source):
+    "helper to import object from module; accept format `path.to.object`"
+    modname, modattr = source.rsplit(".",1)
+    mod = __import__(modname, fromlist=[modattr], level=0)
+    return getattr(mod, modattr)
+
+class _LazyOverlayModule(ModuleType):
+    """proxy module which overlays original module,
+    and lazily imports specified attributes.
+
+    this is mainly used to prevent importing of resources
+    that are only needed by certain password hashes,
+    yet allow them to be imported from a single location.
+
+    used by :mod:`passlib.utils`, :mod:`passlib.utils.crypto`,
+    and :mod:`passlib.utils.compat`.
+    """
+
+    @classmethod
+    def replace_module(cls, name, attrmap):
+        orig = sys.modules[name]
+        self = cls(name, attrmap, orig)
+        sys.modules[name] = self
+        return self
+
+    def __init__(self, name, attrmap, proxy=None):
+        ModuleType.__init__(self, name)
+        self.__attrmap = attrmap
+        self.__proxy = proxy
+        self.__log = logging.getLogger(name)
+
+    def __getattr__(self, attr):
+        proxy = self.__proxy
+        if proxy and hasattr(proxy, attr):
+            return getattr(proxy, attr)
+        attrmap = self.__attrmap
+        if attr in attrmap:
+            source = attrmap[attr]
+            if callable(source):
+                value = source()
+            else:
+                value = _import_object(source)
+            setattr(self, attr, value)
+            self.__log.debug("loaded lazy attr %r: %r", attr, value)
+            return value
+        raise AttributeError("'module' object has no attribute '%s'" % (attr,))
+
+    def __repr__(self):
+        proxy = self.__proxy
+        if proxy:
+            return repr(proxy)
+        else:
+            return ModuleType.__repr__(self)
+
+    def __dir__(self):
+        attrs = set(dir(self.__class__))
+        attrs.update(self.__dict__)
+        attrs.update(self.__attrmap)
+        proxy = self.__proxy
+        if proxy is not None:
+            attrs.update(dir(proxy))
+        return list(attrs)
+
+# replace this module with overlay that will lazily import attributes.
+_LazyOverlayModule.replace_module(__name__, _lazy_attrs)
+
+#=============================================================================
+# eof
+#=============================================================================