1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
|
"""passlib.utils.compat - python 2/3 compatibility helpers"""
#=============================================================================
# figure out what we're running
#=============================================================================
#------------------------------------------------------------------------
# python version
#------------------------------------------------------------------------
import sys
# make sure it's not an unsupported version, even if we somehow got this far
if sys.version_info < (3, 5):
raise RuntimeError("Passlib requires Python >= 3.5 (as of passlib 1.8)")
#------------------------------------------------------------------------
# python implementation
#------------------------------------------------------------------------
JYTHON = sys.platform.startswith('java')
PYPY = hasattr(sys, "pypy_version_info")
if PYPY and sys.pypy_version_info < (2,0):
raise RuntimeError("passlib requires pypy >= 2.0 (as of passlib 1.7)")
#=============================================================================
# common imports
#=============================================================================
import logging; log = logging.getLogger(__name__)
def add_doc(obj, doc):
"""add docstring to an object"""
obj.__doc__ = doc
#=============================================================================
# the default exported vars
#=============================================================================
__all__ = [
# type detection
## 'is_mapping',
'num_types',
'unicode_or_bytes',
# unicode/bytes types & helpers
'bascii_to_str',
'str_to_bascii',
'join_unicode', 'join_bytes',
# context helpers
'nullcontext',
# introspection
'get_method_function', 'add_doc',
]
# begin accumulating mapping of lazy-loaded attrs,
# 'merged' into module at bottom
_lazy_attrs = dict()
#=============================================================================
# unicode & bytes types
#=============================================================================
#: alias for isinstance() tests to detect any string type
unicode_or_bytes = (str, bytes)
#=============================================================================
# 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 True: # legacy PY3 indent
def bascii_to_str(s):
assert isinstance(s, bytes)
return s.decode("ascii")
def str_to_bascii(s):
assert isinstance(s, str)
return s.encode("ascii")
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)
# TODO: move docstrings to funcs...
add_doc(bascii_to_str, "helper to convert ascii bytes -> native str")
add_doc(str_to_bascii, "helper to convert ascii native str -> bytes")
# byte_elem_value -- function to convert byte element to integer -- a noop under PY3
add_doc(iter_byte_chars, "iterate over byte string as sequence of 1-byte strings")
#=============================================================================
# numeric
#=============================================================================
num_types = (int, float)
#=============================================================================
# typing
#=============================================================================
##def is_mapping(obj):
## # non-exhaustive check, enough to distinguish from lists, etc
## return hasattr(obj, "items")
#=============================================================================
# introspection
#=============================================================================
def get_method_function(func):
"""given (potential) method, return underlying function"""
return getattr(func, "__func__", func)
#=============================================================================
# context managers
#=============================================================================
try:
# new in py37
from contextlib import nullcontext
except ImportError:
class nullcontext(object):
"""
Context manager that does no additional processing.
"""
def __init__(self, enter_result=None):
self.enter_result = enter_result
def __enter__(self):
return self.enter_result
def __exit__(self, *exc_info):
pass
#=============================================================================
# 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.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
#=============================================================================
|
