-
Notifications
You must be signed in to change notification settings - Fork 52
/
utils.py
251 lines (204 loc) · 7.23 KB
/
utils.py
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
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
"""Utilities related to handling / interacting with wheel files."""
import contextlib
import csv
import hashlib
import io
import os
import re
import sys
from collections import namedtuple
from configparser import ConfigParser
from email.message import Message
from email.parser import FeedParser
from typing import (
TYPE_CHECKING,
BinaryIO,
Callable,
Iterable,
Iterator,
NewType,
Optional,
Tuple,
Union,
cast,
)
from installer.records import RecordEntry
if TYPE_CHECKING:
from installer.scripts import LauncherKind, ScriptSection
Scheme = NewType("Scheme", str)
AllSchemes = Tuple[Scheme, ...]
__all__ = [
"parse_metadata_file",
"parse_wheel_filename",
"copyfileobj_with_hashing",
"get_launcher_kind",
"fix_shebang",
"construct_record_file",
"parse_entrypoints",
"make_file_executable",
"WheelFilename",
"SCHEME_NAMES",
]
# Borrowed from https://github.com/python/cpython/blob/v3.9.1/Lib/shutil.py#L52
_WINDOWS = os.name == "nt"
_COPY_BUFSIZE = 1024 * 1024 if _WINDOWS else 64 * 1024
# According to https://www.python.org/dev/peps/pep-0427/#file-name-convention
_WHEEL_FILENAME_REGEX = re.compile(
r"""
^
(?P<distribution>.+?)
-(?P<version>.*?)
(?:-(?P<build_tag>\d[^-]*?))?
-(?P<tag>.+?-.+?-.+?)
\.whl
$
""",
re.VERBOSE | re.UNICODE,
)
WheelFilename = namedtuple(
"WheelFilename", ["distribution", "version", "build_tag", "tag"]
)
# Adapted from https://github.com/python/importlib_metadata/blob/v3.4.0/importlib_metadata/__init__.py#L90 # noqa
_ENTRYPOINT_REGEX = re.compile(
r"""
(?P<module>[\w.]+)\s*
(:\s*(?P<attrs>[\w.]+))\s*
(?P<extras>\[.*\])?\s*$
""",
re.VERBOSE | re.UNICODE,
)
# According to https://www.python.org/dev/peps/pep-0427/#id7
SCHEME_NAMES = cast(AllSchemes, ("purelib", "platlib", "headers", "scripts", "data"))
def parse_metadata_file(contents: str) -> Message:
"""Parse :pep:`376` ``PKG-INFO``-style metadata files.
``METADATA`` and ``WHEEL`` files (as per :pep:`427`) use the same syntax
and can also be parsed using this function.
:param contents: The entire contents of the file
"""
feed_parser = FeedParser()
feed_parser.feed(contents)
return feed_parser.close()
def parse_wheel_filename(filename: str) -> WheelFilename:
"""Parse a wheel filename, into it's various components.
:param filename: The filename to parse
"""
wheel_info = _WHEEL_FILENAME_REGEX.match(filename)
if not wheel_info:
raise ValueError(f"Not a valid wheel filename: {filename}")
return WheelFilename(*wheel_info.groups())
def copyfileobj_with_hashing(
source: BinaryIO,
dest: BinaryIO,
hash_algorithm: str,
) -> Tuple[str, int]:
"""Copy a buffer while computing the content's hash and size.
Copies the source buffer into the destination buffer while computing the
hash of the contents. Adapted from :any:`shutil.copyfileobj`.
:param source: buffer holding the source data
:param dest: destination buffer
:param hash_algorithm: hashing algorithm
:return: size, hash digest of the contents
"""
hasher = hashlib.new(hash_algorithm)
size = 0
while True:
buf = source.read(_COPY_BUFSIZE)
if not buf:
break
hasher.update(buf)
dest.write(buf)
size += len(buf)
return hasher.hexdigest(), size
def get_launcher_kind() -> "LauncherKind": # pragma: no cover
"""Get the launcher kind for the current machine."""
if os.name != "nt":
return "posix"
if "amd64" in sys.version.lower():
return "win-amd64"
if "(arm64)" in sys.version.lower():
return "win-arm64"
if "(arm)" in sys.version.lower():
return "win-arm"
if sys.platform == "win32":
return "win-ia32"
raise NotImplementedError("Unknown launcher kind for this machine")
@contextlib.contextmanager
def fix_shebang(stream: BinaryIO, interpreter: str) -> Iterator[BinaryIO]:
"""Replace ``#!python`` shebang in a stream with the correct interpreter.
:param stream: stream to modify
:param interpreter: "correct interpreter" to substitute the shebang with
:returns: A context manager, that provides an appropriately modified stream.
"""
stream.seek(0)
if stream.read(8) == b"#!python":
new_stream = io.BytesIO()
# write our new shebang
new_stream.write(f"#!{interpreter}\n".encode())
# copy the rest of the stream
stream.seek(0)
stream.readline() # skip first line
while True:
buf = stream.read(_COPY_BUFSIZE)
if not buf:
break
new_stream.write(buf)
new_stream.seek(0)
yield new_stream
new_stream.close()
else:
stream.seek(0)
yield stream
def construct_record_file(
records: Iterable[Tuple[Scheme, RecordEntry]],
prefix_for_scheme: Callable[[Scheme], Optional[str]] = lambda _: None,
) -> BinaryIO:
"""Construct a RECORD file.
:param records:
``records`` as passed into :any:`WheelDestination.finalize_installation`
:param prefix_for_scheme:
function to get a prefix to add for RECORD entries, within a scheme
:return: A stream that can be written to file. Must be closed by the caller.
"""
stream = io.TextIOWrapper(
io.BytesIO(), encoding="utf-8", write_through=True, newline=""
)
writer = csv.writer(stream, delimiter=",", quotechar='"', lineterminator="\n")
for scheme, record in records:
writer.writerow(record.to_row(prefix_for_scheme(scheme)))
stream.seek(0)
return stream.detach()
def parse_entrypoints(text: str) -> Iterable[Tuple[str, str, str, "ScriptSection"]]:
"""Parse ``entry_points.txt``-style files.
:param text: entire contents of the file
:return:
name of the script, module to use, attribute to call, kind of script (cli / gui)
"""
# Borrowed from https://github.com/python/importlib_metadata/blob/v3.4.0/importlib_metadata/__init__.py#L115 # noqa
config = ConfigParser(delimiters="=")
config.optionxform = str # type: ignore
config.read_string(text)
for section in config.sections():
if section not in ["console_scripts", "gui_scripts"]:
continue
for name, value in config.items(section):
assert isinstance(name, str)
match = _ENTRYPOINT_REGEX.match(value)
assert match
module = match.group("module")
assert isinstance(module, str)
attrs = match.group("attrs")
# TODO: make this a proper error, which can be caught.
assert attrs is not None
assert isinstance(attrs, str)
script_section = cast("ScriptSection", section[: -len("_scripts")])
yield name, module, attrs, script_section
def _current_umask() -> int:
"""Get the current umask which involves having to set it temporarily."""
mask = os.umask(0)
os.umask(mask)
return mask
# Borrowed from:
# https://github.com/pypa/pip/blob/0f21fb92/src/pip/_internal/utils/unpacking.py#L93
def make_file_executable(path: Union[str, "os.PathLike[str]"]) -> None:
"""Make the file at the provided path executable."""
os.chmod(path, (0o777 & ~_current_umask() | 0o111))