Spaces:
Running
Running
File size: 5,081 Bytes
1d777c4 |
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 |
import os
import sysconfig
def reset_tzpath(to=None):
global TZPATH
tzpaths = to
if tzpaths is not None:
if isinstance(tzpaths, (str, bytes)):
raise TypeError(
f"tzpaths must be a list or tuple, "
+ f"not {type(tzpaths)}: {tzpaths!r}"
)
if not all(map(os.path.isabs, tzpaths)):
raise ValueError(_get_invalid_paths_message(tzpaths))
base_tzpath = tzpaths
else:
env_var = os.environ.get("PYTHONTZPATH", None)
if env_var is not None:
base_tzpath = _parse_python_tzpath(env_var)
else:
base_tzpath = _parse_python_tzpath(
sysconfig.get_config_var("TZPATH")
)
TZPATH = tuple(base_tzpath)
def _parse_python_tzpath(env_var):
if not env_var:
return ()
raw_tzpath = env_var.split(os.pathsep)
new_tzpath = tuple(filter(os.path.isabs, raw_tzpath))
# If anything has been filtered out, we will warn about it
if len(new_tzpath) != len(raw_tzpath):
import warnings
msg = _get_invalid_paths_message(raw_tzpath)
warnings.warn(
"Invalid paths specified in PYTHONTZPATH environment variable. "
+ msg,
InvalidTZPathWarning,
)
return new_tzpath
def _get_invalid_paths_message(tzpaths):
invalid_paths = (path for path in tzpaths if not os.path.isabs(path))
prefix = "\n "
indented_str = prefix + prefix.join(invalid_paths)
return (
"Paths should be absolute but found the following relative paths:"
+ indented_str
)
def find_tzfile(key):
"""Retrieve the path to a TZif file from a key."""
_validate_tzfile_path(key)
for search_path in TZPATH:
filepath = os.path.join(search_path, key)
if os.path.isfile(filepath):
return filepath
return None
_TEST_PATH = os.path.normpath(os.path.join("_", "_"))[:-1]
def _validate_tzfile_path(path, _base=_TEST_PATH):
if os.path.isabs(path):
raise ValueError(
f"ZoneInfo keys may not be absolute paths, got: {path}"
)
# We only care about the kinds of path normalizations that would change the
# length of the key - e.g. a/../b -> a/b, or a/b/ -> a/b. On Windows,
# normpath will also change from a/b to a\b, but that would still preserve
# the length.
new_path = os.path.normpath(path)
if len(new_path) != len(path):
raise ValueError(
f"ZoneInfo keys must be normalized relative paths, got: {path}"
)
resolved = os.path.normpath(os.path.join(_base, new_path))
if not resolved.startswith(_base):
raise ValueError(
f"ZoneInfo keys must refer to subdirectories of TZPATH, got: {path}"
)
del _TEST_PATH
def available_timezones():
"""Returns a set containing all available time zones.
.. caution::
This may attempt to open a large number of files, since the best way to
determine if a given file on the time zone search path is to open it
and check for the "magic string" at the beginning.
"""
from importlib import resources
valid_zones = set()
# Start with loading from the tzdata package if it exists: this has a
# pre-assembled list of zones that only requires opening one file.
try:
with resources.open_text("tzdata", "zones") as f:
for zone in f:
zone = zone.strip()
if zone:
valid_zones.add(zone)
except (ImportError, FileNotFoundError):
pass
def valid_key(fpath):
try:
with open(fpath, "rb") as f:
return f.read(4) == b"TZif"
except Exception: # pragma: nocover
return False
for tz_root in TZPATH:
if not os.path.exists(tz_root):
continue
for root, dirnames, files in os.walk(tz_root):
if root == tz_root:
# right/ and posix/ are special directories and shouldn't be
# included in the output of available zones
if "right" in dirnames:
dirnames.remove("right")
if "posix" in dirnames:
dirnames.remove("posix")
for file in files:
fpath = os.path.join(root, file)
key = os.path.relpath(fpath, start=tz_root)
if os.sep != "/": # pragma: nocover
key = key.replace(os.sep, "/")
if not key or key in valid_zones:
continue
if valid_key(fpath):
valid_zones.add(key)
if "posixrules" in valid_zones:
# posixrules is a special symlink-only time zone where it exists, it
# should not be included in the output
valid_zones.remove("posixrules")
return valid_zones
class InvalidTZPathWarning(RuntimeWarning):
"""Warning raised if an invalid path is specified in PYTHONTZPATH."""
TZPATH = ()
reset_tzpath()
|